380kv ct-vt calculation_c4_rev_d 17.12.09
TRANSCRIPT
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BY:-
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DATE:-
BY
DATE:-
BY:-
DATE:-
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DATE:- DATE
INDEX PLANT REV NO.
DMS
(CROSS BAY C#4)
SEC-ERB CAD-E (2002/03)
EXCEL
01 OF 50 D
3-083300.01 DWG.CONT.SHT. EE-086950
THIS DRAWING IS NOT
TO BE USED FOR
CONSTRUCTION OF
FOR ORDERING
MATERIALS UNTIL
CERTIFIED AND
DATED
DRAWING TITLE DRAWING NO. SHEET NO.
380kV CT SIZING CALCULATIONA T201 EE-086959
ABU-HADRIYAH 380/115kV BSP
KHURSANIYAH
ENG'G. DEPT.
CERTIFIED.
AS BUILT BY
CHECKED
JA
22.12.08
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DATE:- 20.12.08
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SAUDI ARABIA JOB ORDER NO.
RJP
RJP
380kV CT/VT SIZING CALCULATION
25.0
6.2
009
17.1
2.2
009
AP
PR
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JA
JA
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Saudi Electricity CompanyEastern Region Branch
PROJECT:
ABU-HADRIYAH
380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
INDEX
SR. NO. SHEET NO.
1.0 1
1.1 1
1.2 11.3
1.3 2
2.0 3
2.1 3
2.2 5
2.3 1216
2.4 14
2.5 15
2.6 16
2.7 20
2.8 24
2.9 25
2.10 31
2.11 34
2.12 35
2.13 35
2.14 36
2.15 36
2.16 37
2.17 38
2.18 39
2.19 40
2.20 40
2.21 41
2.22 41
CT: 810 B1.C3 :- OHL FEEDER SET-2 PROTECTION (7SA522)
CT: 810 B1.C4 :- METERING
CT: 810 F.C2 :- BUS-BAR PROTECTION MAIN-2 (MFAC14)
CT: 810 F.C1 :- BUS-BAR PROTECTION MAIN-1 (MCAG 14)
CT: 811 B2.C4 :- METERING
CT: 811 B1.C1 :- BF PROTECTION (RAICA)
CT: 811 B1.C2 :- OHL FEEDER SET-1 PROTECTION (RED 670)
CT: 811 B1.C3 :- OHL FEEDER SET-2 PROTECTION (MiCOM P546)
CT: 811 B1.C4 :- METERING
CT: 810 F.C3 :- SPARE
DESCRIPTION
GENERAL DESIGN CRITERIA FOR CT CALCULATION
SYSTEM DESIGN DATA
CT: 811 B2.C3 :- OHL FEEDER SET-2 PROTECTION (7SA522)
DESIGN BASIS AND REFERENCES FOR CT CALCULATION
CT LEAD RESISTANCE CALCULATION
CT CALCULATION FOR THE FOLLOWING CT's.
CT: 810 B1.C1 :- BF PROTECTION (RAICA)
CT: 810 B1.C2 :- OHL FEEDER SET-1 PROTECTION (REL 531)
CT: 812 B2.C1 :- BF PROTECTION
CT: 811 B2.C2 :-OHL FEEDER SET-1 PROTECTION (REL 531)
CT: 811 B2.C1 :- SPARE
CT: 812 F.C1 :- BUS-BAR PROTECTION MAIN-1 (MCAG 14)
CT: 812 F.C2 :- BUS-BAR PROTECTION MAIN-2 (MFAC14)
CT: 812 F.C3 :- SPARE
CT: 812 B2.C4 :- METERING
CT: 812 B2.C3 :- OHL FEEDER SET-2 PROTECTION (7SA522)
CT: 812 B2.C2 :- OHL FEEDER SET-1 PROTECTION (REL 531)
BAY NUMBER: CROSS BAY C4
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH
380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
3.00 42
47
49
LINE VT SIZING CALCULATION
BUS-1 VT SIZING CALCULATION
ATTACHMENTS:
ANNEXURE-1 CT REQUIREMENT OF RELAY
ANNEXURE-2 VA REQUIREMENT OF RELAY
BUS-2 VT SIZING CALCULATION
ANNEXURE-4A 380kV GIS DATA SCHEDULE FROM AREVA
ANNEXURE-5 MANIFA SUBSTATION ELECTRICAL LAYOUT
ANNEXURE-6 380kV RELAYING & METERING ONE LINE DIAGRAM
ANNEXURE-9 M&I METROSIL CATALOGUE
ANNEXURE-3 SAUDI CABLE CATALOGUE
ANNEXURE-4 380kV GIS CT DATA FROM AREVA
ANNEXURE-7 LINE PARAMETER
ANNEXURE-8 380kV CVT DATA SCHEDULE
BAY NUMBER: CROSS BAY C4
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
1.0 GENERAL DESIGN CRITERIA FOR CT SIZING CALCULATION
1.1 System Design Data:
1.1.1 380kV
1.1.2 > 17 (As per 32-TMSS-02, sh. No. 31 of 53, Annexure-4A)
1.1.3 63000 Amps
1.1.4 63000 Amps
1.1.5 63kA (As per 32-TMSS-02, sh. No. 31 of 53, Annexure-4A)
1.2 DESIGN BASIS AND REFERENCES FOR CT CALCULATION :
1.2.1 CT secondary excitation limiting emf and other parameters of CT's are calculated
at adopted tap setting, as shown in relaying & metering one line diagram.
1.2.2 Lead length considered is 500 meters including safety margin.
Refer to the attached Abuhadriyah substation electrical layout (dwg. No. EA-009912).
Refer Annexure 5 sheet 2.
Thus we have ensured that assumed 500m length is not exceeded by any actual length.
500m is also used as basis for any future modifications for normal S/S life time of 35years.
1.2.3 Safety margin of 20% is considered for protection class CT and 25% for metering class CT in the formulae
for CT calculation as a general and where-ever applicable relay manufacturer's recommendation is followed.
1.2.4 CT specification is considered as per PTS 07EN307 part'F', Appendix-VII and GIS vendor data.
1.2.5 Zs (source Impedance) is calculated based on CB Interrupting capacity. The Line Impedance value will be added
to Zs to derive the fault current (PF & EF) at zone1 end for CT excitation limiting EMF calculation. Only one way
is considered for PF zone1 Ual calculation and 2 way CT lead length is considered for EF zone1 Ual calculation.
CT Calculation for close in fault is done for 3 phase fault level 63kA.
We also have assumed 3km long line in view of any future modifications in the 380kV system,
1.2.6 Annexure-1: CT requirement of relay
Annexure-2: VA burden requirement of relay
Annexure-3: Saudi cable catalogue for CT lead resistance calculation
Annexure-4: CT data from 380kV GIS vendor (TOSHIBA)
Annexure-4A: Data Schedule for 380kV GIS
Annexure-5: Abu-hadriyah substation electrical Layout drawing for CT/VT cable route length (dwg. No. EA-009912)
Annexure-6: 380kV Relaying & Metering one line diagram for cross bay C4.
Annexure-7: Line parameters
Annexure-8: 380kV GIS Data schedule-CCVT
Annexure-9: M&I Metrosil catalogue
Design Fault level (CB Interr. capacity)
System Voltage in kV
380kV system X/R Ratio
380kV Maximum 3 pahse fault level
380kV Maximum P-E fault level :
BAY NUMBER:
CROSS BAY C4
Sheet No.
1 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
1.3 CT LEAD RESISTANCE CALCULATION :
CT secondary lead size considered is 6 sq.mm.
6 sq.mm copper cable resistance at 200C is 3.08 ohms/km.i.e Rdc at 20
0C = 3.08 ohm/km (Refer Annexure-3)
Rdc at 75ºC = R20(1+α20(T2-T1)); α at 20ºC = 0.004,Where α= temperature co-efficient of resistance.
Hence, Rdc at 75ºC = 3.08(1+0.004(75-20));
= 3.76 ohm/km
Consider a distance from 380kV GIS CT to relay panel as per layout attached with considerable
(Refer Annexure-5) safe margin = 500 meter, Lead resistance calculated is,
= 3.76 x 0.5
= 1.88 ohms for 500 meters
BAY NUMBER:
CROSS BAY C4
Sheet No.
2 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.0 CT CALCULATION AS PER RELAY/INSTRUMENT MANUFACTURER'S RECOMMENDATION
2.1 CT: 810 B1.C1
Protection : BF protection (50BF)
Core : CT: 810 B1.C1
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 3.1 Ohms at 2000A tap.
Knee point voltage, Vk Vk > 3700 V at 2000A tap
CT excitation current at 2000A tap in mA Ie < 75
Thermal rating factor 200%
Application : CB Fail Protection (50BF)
Relay Type / Make: "RAICA", ABB,(50BF)
CT CALCULATION:
2.1.1 CT Vk requirement:
For 2000 A
Vk Knee point voltage
I P = Nominal ( rated) CT primary Current = 2000 amps
T = Turn ratio = 1/2000
I s = Nominal ( rated) CT secondary Current = 1 amps
I F = Maximum short circuit current = 63000 amps
IF sec = CT Secondary short circuit current in Amps. = 31.5 amps
RCT = Internal CT secondary resistance = 3.1 ohms
RL = Lead Resistance =2 L x Rpkm / 1000 = 1.88 ohms
RL = Lead resistance of cable. = 1.88 Ohms
=For 6 sq.mm copper cable, RL= 0.00308 ohm/meter at 20ºC.
α at 20ºC = 0.004, RL at 75ºC = RL(1+α20(T2-T1)) RL = 1.88 ohms.
Consider length of cable = 500 meters.
RRAICA= Relay Burden (Refer Annexure-2, Sh. No. 6) = 0.15 VA
RRAICA= Relay resistance = RB / Is 2
= (0.15/12) = 0.15 ohms
BAY NUMBER:
CROSS BAY C4
Sheet No.
3 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
Note:
Maximum Relay burdens occur for 1ph-G fault when both phase & ground BFP O/C relay units are in series.
2x BFP Relay Fault Detectors = 0.30 Ohms
Total= 0.30 ohms Ground o/c relay [1ph-G loop]
0.15 ohms phase o/c relay [3ph]
BFP fault detectors come once main protection operates & initiate BFP. Worst case relay operation (fatest)
is ½ cycle & hence @ maximum peak during fully offset.
CT Requirement considering 20% margin.
General formulae:
Vkrequired > 1.2xOffset for DC x Ifsecondaryx (Connected burden)
Vkrequired > 1.2x2xIf x ( RCT + 2RL + 2x(RRAICA ))
> 1.2x2x31.5 x ( 3.1 + 3.76 + 2x(0.15))
> 541.296 Volts
Since CT rated knee point voltage is 3700V which is greater than 541.3 volts, CT is adequate.
BAY NUMBER:
CROSS BAY C4
Sheet No.
4 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.2 CT: 810 B1.C2
Protection : OHL feeder protection Set-1 (87L-1,21-1)
Core : CT: 810 B1.C2
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 3.1 Ohms at 2000A tap.
Knee point voltage, Vk Vk > 3700 V at 2000A tap
CT excitation current at 2000A tap in mA Ie < 75
Thermal rating factor 200%
Application : OHL feeder protection Set-1 (87L-1,21-1)
Relay Type / Make: "REL 531", ABB
2.2.1 Line Data: (Refer Annexure-7 attached)
Line length as per annexure attached = 44.485 km (Annexure-7)
Line parameter for Abu-hadriyah Al-fadhili line. Refer Annexure-7 for Line parameters.
Z1 = 0.00054+j 0.0098 p.u Base MVA = 100
Z0 = 0.00645+j 0.03112 p.u Base kV = 380
Base Impedance calculated = (BasekV2) = 1444 ohms
Base MVA
Base Current calculated = (Base MVA) = 151.9 amps
√3 x Base kV
Zline in ohms calculated; R1= 0.794 ohms
(Base Impedance x p.u Impedance) X1= 14.15 ohms
R0= 9.314 ohms
X0= 44.94 ohms
X/R = 17 Phase volt.= 219393.1 Volts
sin(tan-1(X/R)) = 0.998 Phase Curr.=63000 Amperes
cos(tan-1(X/R)) = 0.059
BAY NUMBER:
CROSS BAY C4
Sheet No.
5 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.2.2 Source impedance:
Xs = (Ph vol/Ph cu)xsin(tan-1
(X/R)) Rs = (Ph vol/Ph cu)xcos(tan-1
(X/R))
= 380000 x sin(tan-1
(X/R)) = 380000 x cos(tan-1
(X/R))
Sqrt.(3)x63000 Sqrt.(3)x63000
= 3.48 ohms = 0.20 ohms
Z s = 0.2 + j 3.48 ohms
2.2.3 Line impedance:
X1 full Line: Line length x Reactance value/km X0 full Line: Line length x Reactance value/km
= 14.1512 ohms = 44.93728 ohms
R1 full Line: Line length x Resistance value/km R0 full Line: Line length x Resistance value/km
= 0.7942 ohms = 9.3138 ohms
Z1 line = 0.7942 + j 14.15 ohms Z0 line = 9.3 + j 44.94 ohms
2.2.4 THREE PHASE FAULT CONDITION
Close in Fault
Fault current = 63 kA
X/R = 17
Source Imp. Z1=Z2=Z0 =0.2 + j 3.48 ohms
Through fault current at the end of the line:
For 44.485 Km line
Impedance calculated : (Rs + R1) + j(Xs+X1)
(Positive sequence) = (0.2+0.794) + j (3.48+14.15)
= 0.994+j17.63 ohms
ZT1 = 17.66 ohms
Phase fault current = Ph. Volt / Ph. Imp.
= 380000
Sqrt.(3)x17.63
= 12424.57 Amps
Phase fault X/R = 17.63
0.994
= 17.74
BAY NUMBER:
CROSS BAY C4
Sheet No.
6 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
Fault current calculation at the end of zone1 fault i.e 80% of line length:
For 44.485 Km line
Impedance calculated : (Rs+0.8R1) + j(Xs+0.8X1)
(Positive sequence) = (0.2+0.635) + j (3.48+11.32)
= 0.84+j14.8
ZT1 = 14.82 ohms
Phase fault current = Ph. Volt / Ph. Imp.
= 380000
Sqrt.(3)x14.82
= 14800.04 Amps
Phase fault X/R = 14.82
0.835
= 17.75
2.2.5 SINGLE PHASE-GROUND FAULT CONDITION:
Through fault current at the end of the line:
For 44.485 Km line
Impedance calculated : (3Rs+2R1+R0) +
(Loop Impedance) j(3Xs+2X1+X0)
= 11.5+j83.79 ohms
ZT1 = 84.39 ohms
Earth fault current = Ph. Volt / Ph. Imp.
= 380000
Sqrt.(3)x84.39
I0 = 2599.62 Amps
Earth fault X/R = 83.79
11.5
= 7.29
3I0 = 7798.87 Amps
BAY NUMBER:
CROSS BAY C4
Sheet No.
7 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
Fault current calculation at the end of zone1 fault i.e 80% of line length:
For 44.485 Km line
Impedance calculated : (3Rs+0.8x2R1+R0) +
(Loop Impedance) j(3Xs+0.8x2X1+X0)
= 9.32+j69.12 ohms
ZT1 = 69.75 ohms
Earth fault current = Ph. Volt / Ph. Imp.
= 380000
Sqrt.(3)x69.75
= 3145.62 Amps
Earth fault X/R = 69.12
9.32
= 7.42
3I0= = 9436.869326 Amps
2.2.6 CT Requirement : ( As per Annexure-1, Sh. No.20,21)
Eal > Ealreq = {I kmax x I sn} / Ipn x 0.5 x (RCT + RL + SR / Ir 2
) Equation-1
Eal > Ealreq = 2 x {Ikmax x I sn} / Ipn x (RCT + RL + SR / Ir 2 ) Equation-2
Eal > Ealreq = 0.12 x f x Isn x(RCT + RL + SR / Ir 2 ) Equation-3
Eal > Ealreq = (Imin sat x CT factor x Ir) / 100 x (RCT + RL + SR / Ir 2
) Equation-4
Where,
Ikmax = Maximum Primary fundamental frequency fault current for internal close-in faults (A)
Itfdb = Maximum Primary fundamental frequency fault current for external faults (A) that
passes through two CT's (A).
Here for one and half breaker scheme Ikmax is equal to Itfdb.
Ipn = The rated primary CT current (A)
Isn = The rated secondary CT current (A)
Ir = The rated current of the protection IED (A)
SR = The burden of IED 670 a current input channel (VA). SR = 0.25 VA/channel.
f = system frequeny in Hz.
Imin sat= Saturation detector min current ( 100 - 1000% Of Ir) and set at 500%
CT factor = set current scalling factor (0.4 - 1.0)
Where, For 2000 amps
Ealreq=
Eal = = 3700 volts
I K max = Maximum short circuit current-Three phase = 63000 amps
Required secondary e.m.f.
Rated equivalent secondary e.m.f.= Vk
BAY NUMBER:
CROSS BAY C4
Sheet No.
8 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
Itfdb = Maximum Primary fault current for external faults (A) = 63000 amps
I pn = Nominal ( rated) CT primary Current = 2000 amps
I sn = Nominal ( rated) CT secondary Current = 1 amps
RCT = CT secondary winding resistance = 3.1 ohms
RB = = 0.25 ohms
RL = Lead resistance of cable.
=For 6 sq.mm copper cable, RL= 3.08 ohm/kmeter at 20ºC.
α at 20ºC = 0.004, RL at 75ºC = RL(1+α20(T2-T1)) RL 1.88
Consider length of cable = 500 meters. 2RL = 3.76 ohms
I r = = 1 amps
f = = 60 Hz
Imin Sat=
X/R = = 17
Tp = Primary time constant, (L/R)
L/R = (X/(2x 3.14x f )/R
.= ( 17 / 2x 3.14x 60) x 1000 = 45.09 msec
RTFR = Burden value for TFR (Refer Annexure-2,Sh. No.7) = 0.01 VA
Hence, total VA burden including TFR. = 0.26 VA
Voltage developed across CT as per ABB relay catalogue.
At 2000/1 A tap
Considering 20% margin
Eal > Ealreq = {I kmax x I sn} / Ipn x 0.5 x (RCT + RL + SR / Ir 2
) Equation-1
As per REL 531 relay requirement, the factor 0.5( for Tc less than 120ms) is replaced with 0.53 & 0.54
for primary time constant of 200ms and 300ms respectively.
Ealreq = 63000 x 1 x 0.5 x ( 3.1+ 1.88 + 0.27/1^2 ) = 82.5 volts
2000
With 20% extra margin Ealreq = 99.0 volts
Sat saturation detector min current
Burden of relay
Protection terminal rated Current
System ratio
System Frequency
BAY NUMBER:
CROSS BAY C4
Sheet No.
9 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
Eal > Ealreq = 2 x {Ikmax x I sn} / Ipn x (RCT + RL + SR / Ir 2
) Equation-2
As per REL 531 relay requirement, the factor 2 ( for Tc less than 120ms) is replaced with 2.32 & 2.5
for primary time constant of 200ms and 300ms respectively.
Ealreq = 63000 x 1 x 2 x ( 3.1+ 1.88 + 0.27/1^2 ) = 330.1 volts
2000
With 20% extra margin Ealreq = 396.1 volts
Eal > Ealreq = 0.12 x f x Isn x (RCT + RL + SR / Ir 2
) Equation-3
Ealreq = 0.12 x 50 x 1x(3.1+ 1.88 +0.27/12
) = 31.4 volts
With 20% extra margin Ealreq = 37.7 volts
Eal > Ealreq = (Imin sat x CT factor x Ir) / 100 x (RCT + RL + SR / Ir 2 ) Equation-4
Ealreq = 500 x 1 x 1x(3.1+ 1.88 +0.27/12
) = 26.2 volts
100
With 20% extra margin Ealreq = 31.4 volts
Since CT rated knee point voltage is 3700V which is greater than the required value,
the proposed CT is adequate.
The Voltage developed across the CT secondary for distance protection (21L) feature as per
ABB catalogue. (Refer Annexure-1 Sh. No. 22 )
Requirement -1
At 2000/1 A tap
Eal > Ealreq = {I kmax x I sn} / Ipn x a x (RCT + RL + SR / Ir 2
) Equation-5
a' = 2 for primary time constant less than 50msec.
With 20% extra margin
Ealreq = 63000 x 1.2 x 2 x ( 3.1+ 1.88 + 0.27/1^2 ) = 538.3 volts
2000
BAY NUMBER:
CROSS BAY C4
Sheet No.
10 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
Requirement -2
Eal > Ealreq = Ikzone1x 7 x (Isn / Ipn) x (RCT + RL + SR / Ir 2
) Equation-6
k' = 7 for primary time constant greater than 30 msec.
Ikzone1= Maximum primary fundamental fault current at the end of zone 1 reach.
Considering 80% of actual line length = 14800.04 Amps
(Refer above fault current calculation at the end of zone1 reach considering actual line length)
At 2000/1 A tap and with 20% extra margin
Ealreq = 14800 x 1.2 x 7 x ( 3.1+ 1.88 +0.27/12
) = 442.58038 volts
2000
Since CT rated knee point voltage is 3700V which is greater than the required value,
the proposed CT is adequate.
BAY NUMBER:
CROSS BAY C4
Sheet No.
11 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.3 CT: 810 B1.C3
Protection : OHL feeder protn. -Set-2 (87L-2,21-2)
Core : CT: 810 B1.C3
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 3.1 Ohms at 2000A tap.
Knee point voltage, Vk Vk > 3700 V at 2000A tap
CT excitation current at 2000A tap in mA Ie < 75
Thermal rating factor 200%
Application : OHL feeder protection - Set-2 (87L-2,21-2)
Relay Type/make : ''7SA522 ", Siemens.
2.3.1 CT Calculation
Where For 2000 amps
Vk = Knee point voltage of CT 3700 Volts
RB = Resistance of relay 7SA522 = 0.05 ohms
Rr = Relay resistance
RCT = CT secondary winding resistance = 3.1 ohms
RL = Lead resistance of cable.
For 6 sq.mm copper cable, RL= 3.08 ohm/kmeter at 20ºC.
α at 20ºC = 0.004, RL at 75ºC = RL(1+α20(T2-T1)) RL = 1.88 ohms
Consider length of cable = 500 meters. 2RL= 3.76 ohms
I P = Nominal ( rated) CT primary Current = 2000 amps
I S = Nominal ( rated) CT secondary Current = 1 amps
ISCC max = Maximum short circuit current-Three phase = 63000 amps
VK CT knee point voltage specified = 3700 volts
X/R = System ratio = 17
I f = Maximum value of through fault current for
stability ( multiple of Is) = I SCC max / IP = 31.50
( I f )x( X/R) = 535.5
Tp = Primary time constant, (L/R)
L/R = (X/(2x 3.14x f )/R
.= ( 17 / 2x 3.14x 60) x 1000 = 45.09 msec
BAY NUMBER:
CROSS BAY C4
Sheet No.
12 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
The CT should meet the following Vk requirement as per Siemens publication.
( Refer Annexure-1 Sh. No. 24 )
Vk 1 > {Ktd(a)xIssc max(close-in fault)/1.3xIpn} x Isn x (RB + RCT +RL) For close-in fault
Vk 2 > {Ktd(b)xIssc max(zone-1 end fault)/1.3xIpn} x Isn x (RB + RCT +RL) For zone-1 end fault
Ktd(a) = 2' for primary time constants less than 50ms
Ktd(b) = 5' for primary time constants less than 50ms
Vk1 = Accuracy limiting voltage for close in fault in volts
Vk2 = Accuracy limiting voltage for end of zone 1 line fault in volts
IFZ1 = Maximum secondary fault current for end of zone 1 fault in amps.
Considering actual line length as a worst case, primary fault current (A) calculated is equal 14800.04
Amps. Hence, CT secondary fault current = 14800.04
2000
= 7.40 Amps.
RB = Relay burden
CT requirement for close-in fault condition:
Vk 1 > {Ktd(a)xIssc max(close-in fault)/1.3xIpn} x Isn x (RB + RCT +RL)
= {2 x 63000/1.3x2000} x (0.05 + 3.1 + 1.88) = 244 volts
Vk 2 with 20 % margin = 293 volts
Peak voltage = 413.7 Vpeak
CT requirement for zone1 fault condition:
Vk 2 > {Ktd(b)xIssc max(zone-1 end fault)/1.3xIpn} x Isn x (RB + RCT +RL)
= {5 x 14800/1.3x2000} x (0.05 + 3.1 + 1.88) = 143 volts
Vk 2 with 20 % margin = 172 volts
Peak voltage = 243.0 Vpeak
Since CT rated knee point voltage is 3700V which is greater than the required value,
the proposed CT is adequate.
BAY NUMBER:
CROSS BAY C4
Sheet No.
13 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.4 CT: 810 B1.C4
Protection : Metering
Core : CT: 810 B1.C4
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : 0.2
VA Burden 50 VA
Thermal rating factor 200%
Application : Metering
Burden Calculation (Refer Annexure-2)
a LCP
Ammeter 0.5 VA (Assumed)
b Revenue metering panel
ABB, ALPHA A3R 1E-04 VA ( Refer Annexure-1 Sh. No. 18 )
c Mosaic panel
Watt transducer, , AREVA, ISTAT300 1 VA ( Refer Annexure-1 Sh. No. 13 )
Var transducer, AREVA, ISTAT300 1 VA ( Refer Annexure-1 Sh. No. 13 )
Watt meter, PML ION6200 0.5 VA (Assumed)
Var meter PML ION6200 0.5 VA (Assumed)
d DSM 0.1 VA (Assumed)
Cabling loop (500 meters)
For 4 sq.mm copper cable, RL= 0.00461 ohm/meter at 20ºC.
α at 20ºC = 0.004, RL at 75ºC = RL(1+α20(T2-T1));
Consider length of wire = 500 meters. RL = 2.812 Ohms
2RL = 5.624 VA
Total connected burden, PBC = 9.224 VA
Considering 25% safe margin, connected VA equals to= 11.53 VA
CT Rated burden = 50VA
The total connected burden is less than the CT rated burden i.e 50VA. Hence the CT is adequate.
BAY NUMBER:
CROSS BAY C4
Sheet No.
14 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.5 CT: 810 F.C3
Protection : Spare
Core : CT: 810 F.C3
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 4.65 Ohms at 3000A tap.
Knee point voltage, Vk Vk > 5550 V at 3000A tap
CT excitation current at 3000A tap in mA Ie < 50
Thermal rating factor 200%
Application : Spare
BAY NUMBER:
CROSS BAY C4
Sheet No.
15 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.6 CT: 810 F.C2
Protection : Bus-bar protection (87M2)
Core : CT: 810 F.C2
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 4.65 Ohms at 3000A tap.
Knee point voltage, Vk Vk > 5550 V at 3000A tap
CT excitation current at 3000A tap in mA Ie < 50
Thermal rating factor 200%
NOTE:
Typical bus-bar protection CT's core detail for adjacent cross bay's(3 nos. including future bays)
are shown below.
Protection : Bus-bar protection (87M2)
Core : Core 2
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 4.65 Ohms at 3000A tap.
Knee point voltage, Vk Vk > 5550 V at 3000A tap
CT excitation current at 3000A tap in mA Ie < 50
Thermal rating factor 200%
Application : Bus-Bar Protection-Main-2 (87M2)
Relay Type / Make: "MFAC14", AREVA (Setting range: 25V-325V)
2.6.1 CT Calculation
The setting voltage is determined by the following relationship. (Refer Annexure-1, Sh. No.11)
Vs > 1.2 x If x ( RCT + 2 x RL ) (20% additional margin is taken)
Where For 3000
I P = Nominal ( rated) CT primary Current 3000 amps
I S = Nominal ( rated) CT secondary Current 1 amps
IF = Maximum Fault Current = 63000 amps
If = CT secondary fault current = 21 amps
RCT = Internal CT secondary resistance 4.65 ohms
BAY NUMBER:
CROSS BAY C4
Sheet No.
16 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
RL = Lead resistance of cable. = 1.88 Ohms
=For 6 sq.mm copper cable, RL= 0.00308 ohm/meter at 20ºC.
α at 20ºC = 0.004, RL at 75ºC = RL(1+α20(T2-T1)) RL = 1.88 ohms.
Consider length of cable = 500 meters.
Vk = Specified knee point voltage = 5550 Volts
Calculation of relay setting voltage:
Vs > 1.2 x If x ( RCT + 2 x RL )
Vs > 1.2 x 21 x (4.65 + 3.76 )
Vs > 211.932
Hence select Vs = 275 Vrms
Peak voltage = 388.91 Vpeak
Hence, select a metrosil with setting range 25V- 325V and set at 275 volts.
2.6.2 Metrosil requirement
For this relay Metrosil proposed by the manufacturer has the following parameters.
C = 900
β = 0.25
The current drawn by metrosil at relay setting voltage is given by formulae below.
Irms drawn = 0.52((√2xV')/C))1/β
where V' = voltage in (RMS Sine)
Metrosil recommended for 25-325V relay range @ 2kVrms
Irms drawn = 0.52x((√2x2000)/900)1/0.25
= 50.72 A rms
At voltage setting Vs = 275V, Metrosil draws about 18mA
%Error = (0.018 / Ifs ) x 100
= (0.018 / 21 ) x 100
= 0.086%
Error introduce by metrosil at voltage setting Vs = 275V is 0.086% only.
BAY NUMBER:
CROSS BAY C4
Sheet No.
17 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
Metrosil selection: (Refer Annexure-8)
To limit voltage to 2kVrms, select metrosil same as recommended by MFAC 14 for Vs = 275V
C = 900
β = 0.25
As per M&I materials catalogue attached, for the above 'C' and 'β' characteristics, the recommended
metrosil type is 600A/S1/S1088.
We recommend standard metrosil as per AREVA recommandation only as the relay & scheme is by AREVA.
CT secondary fault current calculated as above = 21 Amps.
Hence, Metrosil withstanding capability is greater than CT secondary current.
2.6.3 Determination of primary fault current setting:
At 3000/1 A tap
Taking Primary fault currrent setting as 1% of maximum fault current i.e 63000 Amps.
1% of bus-bar fault current = 630 amps
Primary Fault current setting Calculation
The primary operating current or fault setting calculated as Ip= { n Im+ Ir +IM+IV}xT
Ip = Primary fault setting
n = number of CTs in parallel including 3 future bays = 8.0
Im = exciting current of each CT at the relay circuit setting voltage 0.005 Amps
RMVTP31 = Resistance of CT supervision relay MVTP 31(Assumed) 90000.0 ohms
IV = Current in MVTP11 relay, (Vs/RMVTP31) 0.003 Amps
IM = current in metrosil at the relay circuit setting voltage 0.018 Amps
Ir = Relay operating current as per MFAC manual for setting range 25-325V 0.03 Amps
Where relay setting voltage is low then current in non linear resistor is ignored.
Primary fault setting (Ip) = {n Im+ Ir +IM+IV}xT
= 273.167
This current is too small as compared to 63kA i.e 0.43% of 63kA.
It is observed that the primary operating current is less than 630A.
Hence, an external shunt resistor (Rsh) needs to be connected inorder to get a primary operating current 630A.
Select shunt resistor to get primary operating current of say 742 Amps.
Ip = { nIe+ Ir +IM+(Vs/Rsh)+IV}xT
742 = {8x0.005+0.03+0.018+(275/Rsh)+0.003} x3000 0.156
The value of external shunt resistor required is calculated as Rsh = 1759.7 ohms
As per AREVA MCAG14 catalogue attached Annexure-2 sheet no. 4
Select a resistor 2700 ohms and set at 1760 ohms with the short time current rating (1 seconds) of 1.3 Amps.
BAY NUMBER:
CROSS BAY C4
Sheet No.
18 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.6.4 Shunt resistor Wattage calculation:
Current in shunt resistor at setting voltage Vs =275 Volts;= 275 = 0.16 Amps.
Shunt resistor Wattage = 0.16x0.16x1760 Watts. 1759.7
45.06 Watts.
Hence, select a shunt resistor of 50 watts.
Hence, Primary operating current calculated =
Primary fault setting (Ip) = {n Im+ Ir +IM+IV+IRsh}T
= 742.0 Amps.
BAY NUMBER:
CROSS BAY C4
Sheet No.
19 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.7 CT: 810 F.C1
Protection : Bus-bar protection (87M1)
Core : CT: 810 F.C1
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 4.65 Ohms at 3000A tap.
Knee point voltage, Vk Vk > 5550 V at 3000A tap
CT excitation current at 3000A tap in mA Iex < 50
Thermal rating factor 200%
NOTE:
Typical bus-bar protection CT's core detail for adjacent cross bay's(3 nos. including future bays)
are shown below.
Protection : Bus-bar protection (87M1)
Core : Core 1
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 4.65 Ohms at 3000A tap.
Knee point voltage, Vk Vk > 5550 V at 3000A tap
CT excitation current at 3000A tap in mA Ie < 50
Thermal rating factor 200%
Application : Bus-Bar Protection-Main-1 (87M1)
Relay Type / Make: "MCAG 14", AREVA (Setting range: 20%-80% of 1A)
2.7.1 CT Requirement
Where For 3000 A
Vk Knee point voltage = 5550 volts
Vs Setting Voltage
I P = Nominal ( rated) CT primary Current = 3000 amps
T = Turn ratio = 1/3000
I s = Nominal ( rated) CT secondary Current = 1 amps
I F = Maximum short circuit current = 63000 amps
If = CT secondary fault current in amps. = 21 amps
BAY NUMBER:
CROSS BAY C4
Sheet No.
20 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
RCT = Internal CT secondary resistance = 4.65 ohms
RL = Lead resistance of cable. = 1.88 Ohms
=For 6 sq.mm copper cable, RL= 0.00308 ohm/meter at 20ºC.
α at 20ºC = 0.004, RL at 75ºC = RL(1+α20(T2-T1)) RL = 1.88 ohms.
Consider length of cable = 500 meters.
RB-MCAG =Relay Burden = 1.00 VA
RRMCAG = Relay resistance = RB / Is 2 = 1.00 ohms
The setting voltage Vs shall be calculated in order to ensure the stability of the protection in
regard with the maximum through fault current If . The setting voltage is determined by the following eqn.
Vs > 1.2 x If x ( RCT + 2 x RL ) (Refer Annexure-1, Sh.No.8)
Vs > 1.2 x 21 x (4.65 + 3.76 )
Vs > 211.932
Hence, select Vs same as Main-2 protection = 275 Vrms
Peak voltage = 388.91 Vpeak
2.7.2 Voltage Llimiting Resistor- Metrosiles: (Refer MCAG 14 sheet attached)
To establish the requirement for a Metrosil the peak voltage needs to exceed 3kV.
Hence V rms needs to be exceeded is equal to (Vpk/ root2) = 2.12 kV
VPK = ( 2 VK ( V f -VK)) 1/2
Where VPK = Peak voltage of the voltage wave form.
Vf = If x Tx(RCT+2RL+Rsr+RRMCAG)
Where
V f = Maximum voltage in absence of saturation = 28547.6 volts
VPK = ( 2x5550x (28547.6- 5550))1/2 = 15977.28 volts
= 15.98 kVolts
VPK is 15.98kV which is more than 3kV hence Metrosiles are required.
Therefore select metrosil to limit the secondary voltage to 3kV peak.
BAY NUMBER:
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Sheet No.
21 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
Metrosil requirement
For this relay Metrosil proposed by the manufacturer has the following parameters.
C = 900
β = 0.25
The current drawn by metrosil at relay setting voltage is given by formulae below.
Irms drawn = 0.52((√2xV')/C))1/β
where V' = voltage in (RMS Sine)
Metrosil recommended for 25-325V relay range @ 2kVrms
Irms drawn = 0.52x((√2x2000)/900)1/0.25
= 50.72 A rms
At voltage setting Vs = 275V, Metrosil draws about 18mA
%Error = (0.018 / Ifs ) x 100
= (0.018 / 21 ) x 100
= 0.387%
Error introduce by metrosil at voltage setting Vs = 275V is 0.086% only.
Metrosil selection: (Refer Annexure-9)
To limit voltage to 2kVrms, select metrosil same as recommended by MCAG14 for Vs = 275V
C = 900
β = 0.25
As per M&I materials catalogue attached, for the above 'C' and 'β' characteristics, the recommended
metrosil type is 600A/S1/S1088.
We recommend standard metrosil as per AREVA recommandation only as the relay & scheme is by AREVA.
CT secondary fault current calculated as above = 21 Amps.
Hence, Metrosil withstanding capability is greater than CT secondary current.
2.7.3 Determination of primary fault current setting:
Taking Primary fault currrent setting as 1% of maximum fault current i.e 63000 Amps.
1% of bus-bar fault current = 630 amps
Primary Fault current setting Calculation
The primary operating current or fault setting calculated as Ip= { n Im+ Ir +IM+IV}xT
Ip = Primary fault setting
n = number of CTs in parallel including 3 future bays = 8.0
Im = exciting current of each CT at the relay circuit setting voltage 0.005 Amps
RMVTP31 = Resistance of CT supervision relay MVTP 31(Assumed) 90000.0 ohms
BAY NUMBER:
CROSS BAY C4
Sheet No.
22 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
IV = Current in MVTP11 relay, (Vs/RMVTP31) 0.003 Amps
IM = current in metrosil at the relay circuit setting voltage (Assumed) '= 0.018 Amps
Ir = Relay setting current 0.20 Amps
Where relay setting voltage is low then current in non linear resistor is ignored.
=
Primary fault setting (Ip) = { n Im+ Ir +IM+IV}xT
{(8x0.005)+0.2+0.018+0.003}x3000
= 783.2 Amps.
2.7.4 Determination of stabilising resistor Rsr: (Refer MCAG 14 Manual attached, Annex-1, Sh. No.10)
Relay circuit Voltage Vs = 275.00 Volts
Relay setting current, Is = 0.20 Amps
Relay burden at 275V setting is considered as 1VA,
Stabilising resistor required, Rsr = (Vs/Ir) - (Relay burden)/(Ir^2) =Rs= 1350.00 ohms
Select a resistor of range (0 -1500 ohms),0.31A continous,1.36A/3sec,1.8A/1sec as per MCAG 14 Manual.
BAY NUMBER:
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Sheet No.
23 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.8 CT: 811 B1.C1
Protection : CB fail protection
Core : CT: 811 B1.C1
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 3.1 Ohms at 2000A tap.
Knee point voltage, Vk Vk > 3700 V at 2000A tap
CT excitation current at 2000A tap in mA Ie < 75
Thermal rating factor 200%
Application : CB Fail Protection (50BF)
Relay Type / Make: "RAICA", ABB,(50BF)
CT calculation same as CT: 810 B1.C1. Refer above CT: 810 B1.C1 for detailed calculation.
BAY NUMBER:
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Sheet No.
24 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.9 CT: 811 B1.C2
Protection : OHL feeder protn. -Set-1 (87L-1,21-1)
Core : CT: 811 B1.C2
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 3.1 Ohms at 2000A tap.
Knee point voltage, Vk Vk > 3700 V at 2000A tap
CT excitation current at 2000A tap in mA Ie < 75
Thermal rating factor 200%
Application : OHL feeder protection Set-1 (87L-1,21-1)
Relay Type / Make: "RED 670", ABB
2.9.1 Line Data: (Refer Annexure-7 attached)
Line length as per annexure attached = 50 km
Z1 = 0.00055+j 0.0108 p.u Base MVA = 100
Z0 = 0.00545+j 0.0322 p.u Base kV = 380
Base Impedance calculated = (BasekV2) = 1444 ohms
Base MVA
Base Current calculated = (Base MVA) = 151.9 amps
√3 x Base kV
Zline in ohms calculated; R1= 0.794 ohms
(Base Impedance x p.u Impedance) X1= 15.6 ohms
R0= 7.87 ohms
X0= 46.5 ohms
X/R = 17 Phase volt.= 219393.1 Volts
sin(tan-1(X/R)) = 0.998 Phase Curr.=63000 Amperes
cos(tan-1(X/R)) = 0.059
2.9.2 Source impedance:
Xs = (Ph vol/Ph cu)xsin(tan-1
(X/R)) Rs = (Ph vol/Ph cu)xcos(tan-1
(X/R))
= 380000 x sin(tan-1
(X/R)) = 380000 x cos(tan-1
(X/R))
Sqrt.(3)x63000 Sqrt.(3)x63000
= 3.48 ohms = 0.20 ohms
Z s = 0.2 + j 3.48 ohms
BAY NUMBER:
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Sheet No.
25 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.9.3 Line impedance:
X1 full Line: Line length x Reactance value/km X0 full Line: Line length x Reactance value/km
= 15.5952 ohms = 46.4968 ohms
R1 full Line: Line length x Resistance value/km R0 full Line: Line length x Resistance value/km
= 0.7942 ohms = 7.8698 ohms
Z1 line = 0.7942 + j 15.6 ohms Z0 line = 7.8698 + j 46.5 ohms
2.9.4 THREE PHASE FAULT CONDITION
Close in Fault
Fault current = 63 kA
X/R = 17
Source Imp. Z1=Z2=Z0 =0.2 + j 3.48 ohms
Through fault current at the end of the line:
1) For 50 Km line
Impedance calculated : (Rs + R1) + j(Xs+X1)
(Positive sequence) = (0.2+0.794) + j (3.48+15.6)
= 0.994+j19.08 ohms
ZT1 = 19.11 ohms
Phase fault current = Ph. Volt / Ph. Imp.
= 380000
Sqrt.(3)x19.11
= 11483.02 Amps
Phase fault X/R = 19.08
0.994
= 19.20
BAY NUMBER:
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Sheet No.
26 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
Fault current calculation at the end of zone1 fault i.e 80% of line length:
1) For 50 Km line
Impedance calculated : (Rs+0.8R1) + j(Xs+0.8X1)
(Positive sequence) = (0.2+0.635) + j (3.48+12.5)
= 0.84+j16
ZT1 = 16.02 ohms
Phase fault current = Ph. Volt / Ph. Imp.
= 380000
Sqrt.(3)x16.02
= 13693.21 Amps
Phase fault X/R = 15.98
0.835
= 19.14
2.9.5 SINGLE PHASE-GROUND FAULT CONDITION:
Through fault current at the end of the line:
1) For 50 Km line
Impedance calculated : (3Rs+2R1+R0) +
(Loop Impedance) j(3Xs+2X1+X0)
= 10.08+j88.12 ohms
ZT1 = 88.69 ohms
Earth fault current = Ph. Volt / Ph. Imp.
= 380000
Sqrt.(3)x88.69
I0 = 2473.58 Amps
Earth fault X/R = 88.12
10.08
= 8.74
3I0 = 7420.73 Amps
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Sheet No.
27 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
Fault current calculation at the end of zone1 fault i.e 80% of line length:
1) For 50 Km line
Impedance calculated : (3Rs+0.8x2R1+R0) +
(Loop Impedance) j(3Xs+0.8x2X1+X0)
= 8.18+j72.5 ohms
ZT1 = 72.96 ohms
Earth fault current = Ph. Volt / Ph. Imp.
= 380000
Sqrt.(3)x72.96
= 3007.03 Amps
Earth fault X/R = 72.50
8.18
= 8.86
3I0= = 9021.097278 Amps
2.9.6 CT Requirement : ( As per Annexure-1, Sh. No.2)
Eal > Ealreq = {I kmax x I sn} / Ipn x (RCT + RL + SR / Ir 2
) Equation-1
Eal > Ealreq = 2 x {I tmax x I sn} / Ipn x (RCT + RL + SR / Ir 2 ) Equation-2
Eal > Ealreq = Itfdb x (Isn / Ipn) x (RCT + RL + SR / Ir 2
) Equation-3
Where,
Ikmax = Maximum Primary fundamental frequency fault current for internal close-in faults (A)
Itfdb = Maximum Primary fundamental frequency fault current for external faults (A) that
passes through two CT's (A).
Here for one and half breaker scheme Ikmax is equal to Itfdb.
Ipn = The rated primary CT current (A)
Isn = The rated secondary CT current (A)
Ir = The rated current of the protection IED (A)
SR = The burden of IED 670 a current input channel (VA). SR = 0.25 VA/channel.
Where, For 2000 amps
Ealreq=
Eal = = 3700 volts
I K max = Maximum short circuit current-Three phase = 63000 amps
Itfdb = Maximum Primary fault current for external faults (A) = 63000 amps
I pn = Nominal ( rated) CT primary Current = 2000 amps
Required secondary e.m.f.
Rated equivalent secondary e.m.f.= Vk
BAY NUMBER:
CROSS BAY C4
Sheet No.
28 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
I sn = Nominal ( rated) CT secondary Current = 1 amps
RCT = CT secondary winding resistance = 3.1 ohms
RB = = 0.25 ohms
RL = Lead resistance of cable.
=For 6 sq.mm copper cable, RL= 3.08 ohm/kmeter at 20ºC.
α at 20ºC = 0.004, RL at 75ºC = RL(1+α20(T2-T1)) RL 1.88
Consider length of cable = 500 meters. 2RL = 3.76 ohms
I r = = 1 amps
f = = 60 Hz
Imin Sat=
X/R = = 17
Tp = Primary time constant, (L/R)
L/R = (X/(2x 3.14x f )/R
.= ( 17 / 2x 3.14x 60) x 1000 = 45.09 msec
RTFR = Burden value for TFR (Refer Annexure-2,Sh. No.7) = 0.01 VA
Hence, total VA burden includong TFR = 0.26 VA
Voltage developed across CT as per ABB relay catalogue (Refer Annexure-1 Sh. No.2 )
At 2000/1 A tap
Considering 20% margin
Eal > Ealreq = {I kmax x I sn} / Ipn x (RCT + RL + SR / Ir 2
) Equation-1
Ealreq = 63000 x 1 x ( 3.1+ 1.88 + 0.26/1^2 ) = 224.3 volts
2000
With 20% extra margin Ealreq = 269.1 volts
Eal > Ealreq = 2 x {I tmax x I sn} / Ipn x (RCT + RL + SR / Ir 2
) Equation-2
Ealreq = 63000 x 1 x 2 x ( 3.1+ 1.88 + 0.26/1^2 ) = 448.6 volts
2000
With 20% extra margin Ealreq = 538.3 volts
System Frequency
Sat saturation detector min current
System ratio
Burden of relay
Protection terminal rated Current
BAY NUMBER:
CROSS BAY C4
Sheet No.
29 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
At 2000/1 A tap
Eal > Ealreq = Itfdb x (Isn / Ipn) x (RCT + RL + SR / Ir 2
) Equation-3
Ealreq = 63000 x 1x(3.1+ 1.88 +0.26/12
) = 224.3 volts
2000
With 20% extra margin Ealreq = 269.1 volts
Since CT rated knee point voltage is 3700V which is greater than the required value,
the proposed CT is adequate.
The Voltage developed across the CT secondary for distance protection (21L) feature as per
ABB catalogue. (Refer Annexure-1 Sh. No. 3 )
Requirement -1
At 2000/1 A tap
Eal > Ealreq = {I kmax x I sn} / Ipn x a x (RCT + RL + SR / Ir 2
) Equation-5
a' = 2 for primary time constant less than 50msec.
With 20% extra margin
Ealreq = 63000 x 1.2 x 2 x ( 3.1+ 1.88 + 0.26/1^2 ) = 538.3 volts
2000
Requirement -2
Eal > Ealreq = Ikzone1x k x (Isn / Ipn) x (RCT + RL + SR / Ir 2
) Equation-6
k' = 6 for primary time constant greater than 30 msec.
Ikzone1= Maximum primary fundamental fault current at the end of zone 1 reach.
At 2000/1 A tap and with 20% extra margin
Ealreq = 13693.21 x 1.2 x 6 x ( 3.1+ 1.88 +0.26/12
) = 350.98 volts
2000
Since CT rated knee point voltage is 3700V which is greater than the required value,
the proposed CT is adequate.
BAY NUMBER:
CROSS BAY C4
Sheet No.
30 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.10 CT: 811 B1.C3
Protection : OHL feeder protn. -Set-2 (87L-2,21-2)
Core : CT: 811 B1.C3
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 3.1 Ohms at 2000A tap.
Knee point voltage, Vk Vk > 3700 V at 2000A tap
CT excitation current at 2000A tap in mA Ie < 75
Thermal rating factor 200%
Application : OHL feeder protection - Set-2 (87L-2,21-2)
Relay Type/make : ''MiCOM P546", Areva.
2.10.1 CT Calculation
Where For 2000 amps
Vk = Knee point voltage of CT 3700 Volts
RB = Resistance of relay P543 = 0.04 ohms
Rr = Relay resistance
RCT = CT secondary winding resistance = 3.1 ohms
RL = Lead resistance of cable.
For 6 sq.mm copper cable, RL= 3.08 ohm/kmeter at 20ºC.
α at 20ºC = 0.004, RL at 75ºC = RL(1+α20(T2-T1)) RL = 1.88 ohms
Consider length of cable = 500 meters. 2RL= 3.76 ohms
I P = Nominal ( rated) CT primary Current = 2000 amps
I S = Nominal ( rated) CT secondary Current = 1 amps
ISCC max = Maximum short circuit current-Three phase = 63000 amps
VK CT knee point voltage specified = 3700 volts
X/R = System ratio = 17
I f = Maximum value of through fault current for
stability ( multiple of Is) = I SCC max / IP = 31.50
( I f )x( X/R) = 535.5
BAY NUMBER:
CROSS BAY C4
Sheet No.
31 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
The CT should meet the following Vk requirement as per Areva publication.
( Refer Annexure-1 Sh. No. 5 - 6 )
Vk1 > K xI n x (RB + RCT +RL) (equation -1) for through fault condition
Vk 2 > KRPA xIFZ1 x (1+X/R)x(RB + RCT +RL+Rr) (equation -2) for zone1 fault condition
Vk3 > Kmax x IFmax x (RB + RCT +RL+Rr) (equation -3) for close-up fault
Vk1 = Accuracy limiting voltage for line through fault condition in volts
Vk2 = Accuracy limiting voltage for end of zone 1 line fault in volts
Vk2 = Accuracy limiting voltage for close in fault in volts
IFZ1 = Maximum secondary fault current for end of zone 1 fault in amps.
For 50kM line length , primary fault current (A) calculated is equal to = 13693.21
Amps. Hence, CT secondary fault current = 13693.21
2000
= 6.85 Amps.
KRPA = Fixed dimensioning factor for zone 1 fault and always = 0.6 (Refer Annex-1, Sh. No. 7)
Kmax = Fixed dimensioning factor for close in fault and always = 1.4 (Refer Annex-1, Sh. No. 7)
RB = Relay burden
Where K is dimensioning factor and depends upon the maximum value of through fault current(as a multiple of In)
and primary system X/R ratio.
For three end current differential schemes relay set at Is1=20%, Is2=2In, K1=30% and K2=100%,
K' is calculated as below. (Refer Annex-1, Sh. No. 6)
For through fault condition the fault current and X/R calculated above are
IF = 11483.02 Amps. (Primary); X/R = 19.20
CT secondary fault currect calculated = 5.74
If x X/R = 110.24
If, If x X/R < 1000xIn,
K> 40 + 0.35 x (If x X/R)
K> 40 + 0.35x(110.24)
K> 78.584
As per AREVA relay catalogue, K > 78.584
BAY NUMBER:
CROSS BAY C4
Sheet No.
32 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
CT requirement for through fault condition:
Vk = K x I n x ( RB + RCT +2RL )
.= 78.584 x 1 x ( 0.04 + 3.1 + 3.76 ) = 542 volts
Vk with 20 % margin = 651 volts
Peak voltage = 920.2 Vpeak
CT requirement for zone1 fault condition:
Vk 2 > KRPA xIFZ1 x (1+X/R)x(RB + RCT +RL+Rr)
= 0.6 x6.85 x (1+19.14) x (0.04 + 3.1 + 1.88) = 415 volts
Vk 2 with 20 % margin = 498 volts
Peak voltage = 704.8 Vpeak
CT requirement for close-up fault condition:
Vk3 > Kmax x IFmax x (RB + RCT +RL+Rr)
= 1.4 x 63000/2000 x (0.04 + 3.1 + 1.88) = 221 volts
Vk 2 with 20 % margin = 266 volts
Peak voltage = 375.7 Vpeak
Since, the CT rated knee point voltage is greater than the calculated value, the proposed CT is adequate.
BAY NUMBER:
CROSS BAY C4
Sheet No.
33 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.11 CT: 811 B1.C4
Protection : Metering
Core : CT: 811 B1.C4
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : 0.2
VA Burden 50 VA
Thermal rating factor 200%
Application : Metering
Burden Calculation (Refer Annexure-2)
a LCP
Ammeter 0.5 VA (Assumed)
b Energy metering panel
NEXUS/1262 3.2 VA (Refer Annex-2, Sh. No. 8)
c Mosaic panel
Watt transducer, , AREVA, ISTAT300 1 VA (Refer Annex-2, Sh. No. 13)
Var transducer, AREVA, ISTAT300 1 VA (Refer Annex-2, Sh. No. 13)
Watt meter, PML ION6200 0.5 VA (Assumed)
Var meter PML ION6200 0.5 VA (Assumed)
d DSM 0.1 VA (Assumed)
Cabling loop (500 meters)
For 4 sq.mm copper cable, RL= 0.00461 ohm/meter at 20ºC.
α at 20ºC = 0.004, RL at 75ºC = RL(1+α20(T2-T1));
Consider length of wire = 500 meters. RL = 2.812 Ohms
2RL = 5.624 VA
Total connected burden, PBC = 12.42 VA
Considering 25% safe margin, connected VA equals to= 15.53 VA
CT Rated burden = 50VA
The total connected burden is less than the CT rated burden i.e 50VA. Hence the CT is adequate.
BAY NUMBER:
CROSS BAY C4
Sheet No.
34 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.12 CT: 811 B2.C4
Protection : Metering
Core : CT: 811 B2.C4
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : 0.2
VA Burden 50 VA
Thermal rating factor 200%
Application : Metering
CT calculation same as CT: 810 B1.C4. Refer above CT: 810 B1.C4 for detailed calculation.
2.13 CT: 811 B2.C3
Protection : OHL feeder protn. -Set-2 (87L-2,21-2)
Core : CT: 811 B2.C3
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 3.1 Ohms at 2000A tap.
Knee point voltage, Vk Vk > 3700 V at 2000A tap
CT excitation current at 2000A tap in mA Ie < 75
Thermal rating factor 200%
Application : OHL feeder protection - Set-2 (87L-2,21-2)
Relay Type/make : ''7SA522", Siemens.
CT calculation same as CT: 810 B1.C3. Refer above CT: 810 B1.C3 for detailed calculation.
BAY NUMBER:
CROSS BAY C4
Sheet No.
35 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.14 CT: 811 B2.C2
Protection : OHL feeder protn. Set-1 (87L-1,21-1)
Core : CT: 811 B2.C2
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 3.1 Ohms at 2000A tap.
Knee point voltage, Vk Vk > 3700 V at 2000A tap
CT excitation current at 2000A tap in mA Ie < 75
Thermal rating factor 200%
Application : OHL feeder protection Set-1 (87L-1,21-1)
Relay Type / Make: "REL 531", ABB
CT calculation same as CT: 810 B1.C2. Refer above CT: 810 B1.C2 for detailed calculation.
2.15 CT: 811 B2.C1
Protection : spare
Core : CT: 811 B2.C1
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 4.65 Ohms at 3000A tap.
Knee point voltage, Vk Vk > 5550 V at 3000A tap
CT excitation current at 3000A tap in mA Ie < 50
Thermal rating factor 200%
Application : spare
BAY NUMBER:
CROSS BAY C4
Sheet No.
36 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.16 CT: 812 F.C1
Protection : Bus-bar protection (87M1)
Core : CT: 812 F.C1
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 4.65 Ohms at 3000A tap.
Knee point voltage, Vk Vk > 5550 V at 3000A tap
CT excitation current at 3000A tap in mA Iex < 50
Thermal rating factor 200%
NOTE:
Typical bus-bar protection CT's core detail for adjacent cross bay's(3 nos. including future bays)
are shown below.
Protection : Bus-bar protection (87M1)
Core : Core 1
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 4.65 Ohms at 3000A tap.
Knee point voltage, Vk Vk > 5550 V at 3000A tap
CT excitation current at 3000A tap in mA Ie < 50
Thermal rating factor 200%
Application : Bus-Bar Protection-Main-1 (87M1)
Relay Type / Make: "MCAG 14", AREVA (Setting range: 20%-80% of 1A)
CT calculation same as above for 87M1. Refer above CT: 810 F.C1 for detailed calculation.
BAY NUMBER:
CROSS BAY C4
Sheet No.
37 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.17 CT: 812 F.C2
Protection : Bus-bar protection (87M2)
Core : CT: 812 F.C2
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 4.65 Ohms at 3000A tap.
Knee point voltage, Vk Vk > 5550 V at 3000A tap
CT excitation current at 3000A tap in mA Iex < 50
Thermal rating factor 200%
NOTE:
Typical bus-bar protection CT's core detail for adjacent cross bay's(3 nos. including future bays)
are shown below.
Protection : Bus-bar protection (87M2)
Core : Core 2
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 4.65 Ohms at 3000A tap.
Knee point voltage, Vk Vk > 5550 V at 3000A tap
CT excitation current at 3000A tap in mA Ie < 50
Thermal rating factor 200%
Application : Bus-Bar Protection-Main-2 (87M2)
Relay Type / Make: "MFAC 14", AREVA (Setting range: 25V-325V)
CT calculation same as above CT: 810 F.C2. Refer above CT: 810 F.C2 for detailed calculation.
BAY NUMBER:
CROSS BAY C4
Sheet No.
38 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.18 CT: 812 F.C3
Protection : Spare
Core : CT: 812 F.C3
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 4.65 Ohms at 3000A tap.
Knee point voltage, Vk Vk > 5550 V at 3000A tap
CT excitation current at 3000A tap in mA Iex < 50
Thermal rating factor 200%
Application: Spare
BAY NUMBER:
CROSS BAY C4
Sheet No.
39 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.19 CT: 812 B2.C4
Protection : Metering
Core : CT: 812 B2.C4
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : 0.2
VA Burden 50 VA
Thermal rating factor 200%
Application : Metering
CT calculation same as CT: 811 B1.C4. Refer above CT: 811 B1.C4 for detailed calculation.
2.20 CT: 812 B2.C3
Protection : OHL feeder protn. -Set-2 (87L-2,21-2)
Core : CT: 812 B2.C3
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 3.1 Ohms at 2000A tap.
Knee point voltage, Vk Vk > 3700 V at 2000A tap
CT excitation current at 2000A tap in mA Ie < 75
Thermal rating factor 200%
Application : OHL feeder protection - Set-2 (87L-2,21-2)
Relay Type/make : ''MiCOM P546", Areva.
CT calculation same as CT: 811 B1.C3. Refer above CT: 811 B1.C3 for detailed calculation.
BAY NUMBER:
CROSS BAY C4
Sheet No.
40 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
2.21 CT: 812 B2.C2
Protection : OHL feeder protn. Set-1 (87L-1,21-1)
Core : CT: 812 B2.C2
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms ) < 3.1 Ohms at 2000A tap.
Knee point voltage, Vk Vk > 3700 V at 2000A tap
CT excitation current at 2000A tap in mA Ie < 75
Thermal rating factor 200%
Application : OHL feeder protection Set-1 (87L-1,21-1)
Relay Type / Make: "RED 670", ABB
CT calculation same as CT: 811 B1.C2. Refer above CT: 811 B1.C2 for detailed calculation.
2.22 CT: 812 B2.C1
Protection : BF protection (50BF)
Core : CT: 812 B2.C1
CT Ratio : 3000-2500-2000-1500-1250-1000-750 /1A
Class of Accuracy : TPS
CT Secondary resistance at 75º C, RCT ohms < 3.1 Ohms at 2000A tap.
Knee point voltage, Vk Vk > 3700 V at 2000A tap
CT excitation current at 2000A tap in mA Ie < 75
Thermal rating factor 200%
Application : CB Fail Protection (50BF)
Relay Type / Make: "RAICA", ABB,(50BF)
CT calculation same as CT: 810 B1.C1. Refer above CT: 810 B1.C1 for detailed calculation.
BAY NUMBER:
CROSS BAY C4
Sheet No.
41 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
3
3.1 VT LEAD RESISTANCE CALCULATION :
VT secondary lead size considered is 4 sq.mm.
4 sq.mm copper cable resistance at 200C is 4.61 ohms/km.i.e Rdc at 20
0C = 4.61 ohm/km
Rdc at 75ºC = R20(1+α20(T2-T1)); α at 20ºC = 0.004,Where α= temperature co-efficient of resistance.
Hence, Rdc at 75ºC = 4.61(1+0.004(75-20));
= 5.62 ohm/km
Consider a distance from 380kV GIS CT to relay panel as per layout attached with considerable
safe margin = 500 meter, Lead resistance calculated is,
= 5.62 x 0.5
= 2.81 ohms for 500 meters
380kV ABU HADRIYAH- MANIFA LINE-2
CCVT Details :
Core-1 Core-2
VT Ratio : 380kV/√3/110V/√3-110V 380kV/√3/110V/√3-110V
Class : 0.2/3P 0.2/3P
VA Burden : 100 100
Vector group : Star-Star Star-Star
Voltage Factor : 1.2 Cont., 1.2 Cont.,
1.9 for 30 sec 1.9 for 30 sec
Calculation of VT burden :
Calculation of Lead burden:
RL = Lead resistance of wire.
For 4 sq.mm copper cable, RL= 0.00461 ohm/meter at 20ºC.
α at 20ºC = 0.004, RL at 75ºC = RL(1+α20(T2-T1)), RL= 2.81 ohms
Calculation of Lead current at rated burden :(IVT) = 0.1939 Amperes
Lead current is calculated considering Total VA burden.
Hence, Lead current calculated =100/63.5 = 0.19 Amperes
RB= Lead burden, 2xRLx (IVT^2) = 0.2112 VA
RB= (2 x 2.81 x 0.1939 x 0.1939)
380kV VT SIZING CALCULATION
BAY NUMBER:
CROSS BAY C4
Sheet No.
42 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
Core-1 :
Relay type Quantity Unit burdenTotal burden
(VA)
RXBA 4 1 2 2
RED670 1 0.1 0.1
TR2000 1 0.01 0.01
RXBA 4 1 2 2
RXBA 4 1 2 2
RXBA 4 1 2 2
RXBA 4 1 2 2
1 0.2 0.2
RXBA 4 1 2 2
Total VA = 12.31 VA per phase
Hence, total required burden of VT (Meters/relays plus lead burden) = 12.52 VA
.= (VA Connected + VA Lead)
The Burden calculated considering 25% safety margin = 15.7 VA
Since, the connected burden is less than 100VA,the VT burden is adequate.
FFR (98L2) (Ref.) for 25AR (Annexure-2 Sh. No.9)
DSM Assumed
FFR (98) 25AR/A811 FOR AF-2 (Annexure-2 Sh. No.9)
Relays / Instruments
FFR (98L) A811/A812 (Annexure-2 Sh. No.9)
Line set-1 protection (Annexure-2 Sh. No.2)
Transient Fault Recorder (Annexure-2 Sh. No.7)
FFR (98) (Meas.) for set-1 protection (Annexure-2 Sh. No.9)
FFR (98) (Ref.) for set-2 protection (Annexure-2 Sh. No.9)
FFR (98) (Ref.) for Energy meter (Annexure-2 Sh. No.9)
BAY NUMBER:
CROSS BAY C4
Sheet No.
43 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
Core-2:
Relay type Quantity Unit burdenTotal burden
(VA)
KVAS100 1 0.02 0.02
KVAS100 1 0.02 0.02
RXBA 4 1 2 2
RXBA 4 1 2 2
RXBA 4 1 2 2
MICOMP546 1 0.02 0.02
KVAS100 1 0.02 0.02
KVAS100 1 0.02 0.02
RXBA 4 1 2 2
RXBA 4 1 2 2
RXBA 4 1 2 2
KVAS100 1 0.02 0.02
RAEDA1 3 4.4 13.2
Transducer Panel
Voltage transducer for SCADA ISTAT300 1 0.1 0.1
Watt meter Watt transducer for SCADA ISTAT300 1 0.1 0.1
Var meter Var transducer for SCADA ISTAT300 1 0.1 0.1
ION6200 1 0.5 0.5
ION6200 1 0.5 0.5
ION6200 1 0.5 0.5
Energy metering panel
Nexus/1262 1 5+3.2 8.2
RAEDA1 1 4.4 4.4
RXBA 4 1 2 2
LCP
RAEDA1 1 4.4 4.4
ION6200 1 0.5 0.5
Total VA = 46.62 VA per phase
Hence, total required burden of VT (Meters/relays plus lead burden) = 46.83 VA
.= (VA Connected + VA Lead)
The Burden calculated considering 25% safety margin = 58.5 VA
Since, the connected burden is less than 100VA,the provided VT burden is adequate.
Under voltage relay
Under voltage relay
Voltmeter
FFR (98L2) (Meas.) / 25AR (Annexure-2 Sh. No.9)
FFR (98B2) (Meas.) / A812 (Annexure-2 Sh. No.9)
FFR (98) (Meas.) / A811 (Annexure-2 Sh. No.9)
(Annexure-2 Sh. No. 13)
(Annexure-2 Sh. No. 13)
(Annexure-2 Sh. No. 13)
Wattmeter, PML
VARmeter, PML
Energy meter
(Annexure-2 Sh. No. 11)
25MC/A812 (Annexure-2 Sh. No.10)
Assumed
Assumed
Voltmeter, PML
Assumed
FFR (98) (Meas.) for revenue meter
(Annexure-2 Sh. No. 8)
(Annexure-2 Sh. No. 11)
(Annexure-2 Sh. No. 11)
Assumed
(Annexure-2 Sh. No.9)
(Annexure-2 Sh. No.10)
FFR (98L) (Meas.) A811/A812 (Annexure-2 Sh. No.9)
FFR (98) (Ref.) for set-1 protection (Annexure-2 Sh. No.9)
25AR / A812 (Annexure-2 Sh. No.10)
25AR / A811
Relays / Instruments
25MC/A811
FFR (98) (Meas.) for 67N-2 (Annexure-2 Sh. No.9)
Line set-2 protection (Annexure-2 Sh. No.3)
(Annexure-2 Sh. No.10)
25AR / A811 FOR AF-2 (Annexure-2 Sh. No.10)
(27L2), Under voltage relay
BAY NUMBER:
CROSS BAY C4
Sheet No.
44 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
3.3 380kV ABU HADRIYAH- AL-FADHILI LINE-2
CCVT Details :
Core-1 Core-2
VT Ratio : 380kV/√3/110V/√3-110V 380kV/√3/110V/√3-110V
Class : 0.2/3P 0.2/3P
VA Burden : 100 100
Vector group : Star-Star Star-Star
Voltage Factor : 1.2 Cont., 1.2 Cont.,
1.9 for 30 sec 1.9 for 30 sec
Calculation of VT burden :
Calculation of Lead burden:
RL = Lead resistance of wire.
For 4 sq.mm copper cable, RL= 0.00461 ohm/meter at 20ºC.
α at 20ºC = 0.004, RL at 75ºC = RL(1+α20(T2-T1)), RL= 2.81 ohms
Calculation of Lead current at rated burden :(IVT) = 0.1954 Amperes
Lead current is calculated considering Total VA burden.
Hence, Lead current calculated =100/63.5 = 0.20 Amperes
RB= Lead burden, 2xRLx (IVT^2) = 0.2147 VA
RB= (2 x 2.81 x 0.1954 x 0.1954)
Core-1 :
Relay type Quantity Unit burdenTotal burden
(VA)
RXBA 4 1 2 2
REL 531 1 0.2 0.2
TR2000 1 0.01 0.01
RXBA 4 1 2 2
RXBA 4 1 2 2
RXBA 4 1 2 2
RXBA 4 1 2 2
1 0.2 0.2
RXBA 4 1 2 2
Total VA = 12.41 VA per phase
Hence, total required burden of VT (Meters/relays plus lead burden) = 12.62 VA
.= (VA Connected + VA Lead)
The Burden calculated considering 25% safety margin = 15.8 VA
Since, the connected burden is less than 100VA,the VT burden is adequate.
FFR (98L) (Ref.) for 25MC 810 (Annexure-2 Sh. No.9)
DSM Assumed
FFR (98) (Ref.) for 67N-2 (Annexure-2 Sh. No.9)
FFR (98) (Ref.) for Energy meter (Annexure-2 Sh. No.9)
FFR (98L2) (Ref.) for 25AR (Annexure-2 Sh. No.9)
Line set-1 protection (Annexure-2 Sh. No.15)
Transient Fault Recorder (Annexure-2 Sh. No.7)
FFR (98) (Meas.) for 67N-1 (Annexure-2 Sh. No.9)
Relays / Instruments
FFR 98-25AR/A811 FOR MAIN-2 (Annexure-2 Sh. No.9)
BAY NUMBER:
CROSS BAY C4
Sheet No.
45 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
Core-2:
Relay type Quantity Unit burdenTotal burden
(VA)
RASC 1 0.25 0.25
RASC 1 0.25 0.25
RXBA 4 1 2 2
RXBA 4 1 2 2
RXBA 4 1 2 2
7SA522 1 0.1 0.1
RASC 1 0.25 0.25
RASC 1 0.25 0.25
RAEDA1 3 4.4 13.2
RXBA 4 1 2 2
Transducer Panel
Voltage transducer for SCADA ISTAT300 1 0.1 0.1
Watt meter Watt transducer for SCADA ISTAT300 1 0.1 0.1
Var meter Var transducer for SCADA ISTAT300 1 0.1 0.1
PML 1 0.5 0.5
PML 1 0.5 0.5
PML 1 0.5 0.5
Revenue metering panel
ELESTER 1 0.0173 0.0173
RAEDA1 1 4.4 4.4
RXBA 4 1 2 2
LCP
FVS-U-
DC121 4.4 4.4
PML 1 0.5 0.5
Total VA = 35.42 VA per phase
Hence, total required burden of VT (Meters/relays plus lead burden) = 35.63 VA
.= (VA Connected + VA Lead)
The Burden calculated considering 25% safety margin = 44.5 VA
Since, the connected burden is less than 100VA,the provided VT burden is adequate.
FFR (98) (Meas.) for revenue meter (Annexure-2 Sh. No.9)
Under voltage relay Assumed
Voltmeter Assumed
VARmeter Assumed
Revenue meter (Annexure-2 Sh. No. 18)
Under voltage relay (Annexure-2 Sh. No. 11)
(Annexure-2 Sh. No.13)
(Annexure-2 Sh. No.13)
(Annexure-2 Sh. No.13)
Voltmeter Assumed
Wattmeter Assumed
25AR / A810 (Annexure-2 Sh. No.17)
27-L2 Under voltage relay (Annexure-2 Sh. No. 11)
FFR (98B1) (Meas.) /A810 (Annexure-2 Sh. No.9)
25AR / A811 FOR MAIN-2 (Annexure-2 Sh. No.17)
FFR (98) (Ref.) for 67N-1 (Annexure-2 Sh. No.9)
FFR (98) (Meas.) for 67N-2 (Annexure-2 Sh. No.9)
Line set-2 protection (Annexure-2 Sh. No.16)
Relays / Instruments
25MC/A811 (Annexure-2 Sh. No.17)
25MC/A810 (Annexure-2 Sh. No.17)
FFR (98L) (Meas.) A810/A811 (Annexure-2 Sh. No.9)
BAY NUMBER:
CROSS BAY C4
Sheet No.
46 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
3.4 380kV BUS1-VT (Refer Annexure-4A)
VT Details :
Core-1 Core-2
VT Ratio : 380kV/√3/110V/√3-110V 380kV/√3/110V/√3-110V
Class : 0.2/3P 0.2/3P
VA Burden : 100 100
Vector group : Star-Star Star-Star
Voltage Factor : 1.2 Cont., 1.2 Cont.,
1.9 for 30 sec 1.9 for 30 sec
Calculation of VT burden :
Calculation of Lead burden:
RL = Lead resistance of wire.
For 4 sq.mm copper cable, RL= 0.00461 ohm/meter at 20ºC.
α at 20ºC = 0.004, RL at 75ºC = RL(1+α20(T2-T1)), RL= 2.81 ohms
Calculation of Lead current at rated burden :(IVT) = 0.0945 Amperes
Lead current is calculated considering Total VA burden.
Hence, Lead current calculated =100/63.5 = 0.09 Amperes
RB= Lead burden, 2xRLx (IVT^2) = 0.0502 VA
RB= (2 x 2.81 x 0.0945 x 0.0945)
Core-1 :
Relay type Quantity Unit burdenTotal burden
(VA)
RXBA 4 1 2 2
RXBA 4 1 2 2
RXBA 4 1 2 2
Total VA = 6 VA per phase
Hence, total required burden of VT (Meters/relays plus lead burden) = 6.05 VA
.= (VA Connected + VA Lead)
Considering 25% safety margin for any additional FFR relay required.
The Burden calculated considering 25% safety margin = 7.6 VA
Since, the connected burden is less than 100VA,the VT burden is adequate.
FFR (98B1) (Meas.) 25AR/810 (Annexure-2 Sh. No.9)
FFR (98B1) (Meas.) 25AR/807 (Annexure-2 Sh. No.9)
FFR (98B1)-25MC/A810 (Annexure-2 Sh. No.9)
Relays / Instruments
BAY NUMBER:
CROSS BAY C4
Sheet No.
47 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
Core-2:
Relay type Quantity Unit burdenTotal burden
(VA)
RASC 1 0.25 0.25
KVAS100 1 0.02 0.02
RASC 1 0.25 0.25
RXBA 4 1 2 2
RXBA 4 1 2 2
RXBA 4 1 2 2
RASC 1 0.25 0.25
RASC 1 0.25 0.25
TR2000 1 0.01 0.01
1 0.2 0.2
Transducer panel
Voltage transducer for SCADA ISTAT300 1 0.1 0.1
PML 1 0.5 0.5
LCC
PML 1 0.5 0.5
Total VA = 8.33 VA per phase
Hence, total required burden of VT (Meters/relays plus lead burden) = 8.38 VA
.= (VA Connected + VA Lead)
Considering 25% safety margin for any additional FFR relay required.
The Burden calculated considering 25% safety margin = 10.5 VA
Since, the connected burden is less than 100VA,the provided VT burden is adequate.
25MC/A804 (Annexure-2 Sh. No.17)
25MC/A807 (Annexure-2 Sh. No.10)
25MC/A810 (Annexure-2 Sh. No.17)
98B1-25MC/810 (Annexure-2 Sh. No.9)
25AR / A807 (Annexure-2 Sh. No.17)
98B1-25AR/807 (Annexure-2 Sh. No.9)
98B1-25AR/810
DSM Assumed
(Annexure-2 Sh. No.9)
25AR / A810
Transient Fault Recorder (Annexure-2 Sh. No.7)
Voltmeter
AssumedVoltmeter
Relays / Instruments
(Annexure-2 Sh. No.17)
(Annexure-2 Sh. No.13)
Assumed
BAY NUMBER:
CROSS BAY C4
Sheet No.
48 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
3.5 380kV BUS2-VT
VT Details : (Refer Annexure-4A)
Core-1 Core-2
VT Ratio : 380kV/√3/110V/√3-110V 380kV/√3/110V/√3-110V
Class : 0.2/3P 0.2/3P
VA Burden : 100 100
Vector group : Star-Star Star-Star
Voltage Factor : 1.2 Cont., 1.2 Cont.,
1.9 for 30 sec 1.9 for 30 sec
Calculation of VT burden :
Calculation of Lead burden:
RL = Lead resistance of wire.
For 4 sq.mm copper cable, RL= 0.00461 ohm/meter at 20ºC.
α at 20ºC = 0.004, RL at 75ºC = RL(1+α20(T2-T1)), RL= 2.81 ohms
Calculation of Lead current at rated burden :(IVT) = 0.0945 Amperes
Lead current is calculated considering Total VA burden.
Hence, Lead current calculated =100/63.5 = 0.09 Amperes
RB= Lead burden, 2xRLx (IVT^2) = 0.0502 VA
RB= (2 x 2.81 x 0.0945 x 0.0945)
Core-1 :
Relay type Quantity Unit burdenTotal burden
(VA)
RXBA 4 1 2 2
RXBA 4 1 2 2
RXBA 4 1 2 2
Total VA = 6 VA per phase
Hence, total required burden of VT (Meters/relays plus lead burden) = 6.05 VA
.= (VA Connected + VA Lead)
Considering 25% safety margin for any additional FFR relay required.
The Burden calculated considering 25% safety margin = 7.6 VA
Since, the connected burden is less than 100VA,the VT burden is adequate.
Relays / Instruments
FFR (98B2) (Meas.) 25AR/806 (Annexure-2 Sh. No.9)
FFR (98B2) (Meas.) 25AR/812 (Annexure-2 Sh. No.9)
FFR (98B2)-25MC/A812 (Annexure-2 Sh. No.9)
BAY NUMBER:
CROSS BAY C4
Sheet No.
49 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
PROJECT:
ABU-HADRIYAH 380/115 kV BSP
DOCUMENT TITLE:
380 kV CT/VT SIZING CALCULATION
DOCUMENT NUMBER:
EA-086959
Core-2:
Relay type Quantity Unit burdenTotal burden
(VA)
RASC 1 0.25 0.25
RASC 1 0.25 0.25
KVAS100 1 0.02 0.02
RXBA 4 1 2 2
RXBA 4 1 2 2
RXBA 4 1 2 2
RASC 1 0.25 0.25
KVAS100 1 0.02 0.02
TR2000 1 0.01 0.01
1 0.2 0.2
Transducer panel
Voltage transducer for SCADA ISTAT300 1 0.1 0.1
PML 1 0.5 0.5
LCC
PML 1 0.5 0.5
Total VA = 8.1 VA per phase
Hence, total required burden of VT (Meters/relays plus lead burden) = 8.15 VA
.= (VA Connected + VA Lead)
Considering 25% safety margin for any additional FFR relay required.
The Burden calculated considering 25% safety margin = 10.2 VA
Since, the connected burden is less than 100VA,the provided VT burden is adequate.
25MC/A806
Voltmeter Assumed
(Annexure-2 Sh. No.7)
DSM Assumed
(Annexure-2 Sh. No.13)
Voltmeter Assumed
(Annexure-2 Sh. No.17)
25MC/A809 (Annexure-2 Sh. No.17)
25MC/A812 (Annexure-2 Sh. No.10)
Relays / Instruments
(Annexure-2 Sh. No.9)
98B2-25AR/806 (Annexure-2 Sh. No.9)
98B2-25MC/812
98B2-25AR/812 (Annexure-2 Sh. No.9)
25AR / A806 (Annexure-2 Sh. No.17)
25AR / A812 (Annexure-2 Sh. No.10)
Transient Fault Recorder
BAY NUMBER:
CROSS BAY C4
Sheet No.
50 of 50
ABU-HADRIYAH CONTRACT No.
3-083300.01
Annexure-: CT Requirement of Relay Page 1
ANNEXURE-1
CT requirements of relay
Sr No. Description Make Type Page No.
1 Line differential protection main-1 ABB RED670 2
2 Line differential protection main-2 AREVA MICOMP546 5
3 Busbar differential protection AREVA MCAG14 8
4 Busbar differential protection AREVA MFAC14 11
5 CT circuit supervision relay AREVA MVTP11 15
6 Breaker failure protection relay ABB RAICA 16
7 Transient fault recorder ROCHESTER TR2000 17
8 Line differential protection main-1 ABB REL531 20
9 Line differential protection main-2 SIEMENS 7SA522 24
Annexure-: CT Requirement of Relay Page 2
Annexure-: CT Requirement of Relay Page 3
Annexure-: CT Requirement of Relay Page 4
Annexure-: CT Requirement of Relay Page 5
Annexure-: CT Requirement of Relay Page 6
Annexure-: CT Requirement of Relay Page 7
Annexure-: CT Requirement of Relay Page 8
Annexure-: CT Requirement of Relay Page 9
Annexure-: CT Requirement of Relay Page 10
Annexure-: CT Requirement of Relay Page 11
Annexure-: CT Requirement of Relay Page 12
Annexure-: CT Requirement of Relay Page 13
Annexure-: CT Requirement of Relay Page 14
Annexure-: CT Requirement of Relay Page 15
Annexure-: CT Requirement of Relay Page 16
Annexure-: CT Requirement of Relay Page 17
Annexure-: CT Requirement of Relay Page 18
Annexure-: CT Requirement of Relay Page 19
Annexure-: CT Requirement of Relay Page 20
Annexure-: CT Requirement of Relay Page 21
Annexure-: CT Requirement of Relay Page 22
Annexure-: CT Requirement of Relay Page 23
Annexure-: CT Requirement of Relay Page 24
Annexure-: VA Requirement of Relay Page 1
ANNEXURE-2
VA burden requirements of relay
Sr No. Description Make Type Page No.
1 Line differential protection main-1 ABB RED670 2
2 Line differential protection main-2 AREVA MICOMP546 3
3 Busbar differential protection AREVA MCAG4 4
4 CT circuit supervision relay AREVA MVTP11 5
5 Breaker failure protection relay ABB RAICA 6
6 Transient fault recorder ROCHESTER TR2000 7
7 Energy Meter Electro Ind. NEXUS1262 8
8 Fuse failure relay ABB RXBA4 9
9 Synchro check relay AREVA KVAS100 10
10 Undervoltage relay ABB RAEDA1 11
11 Line differential protection main-1 ABB REL531 12
12 Transducer AREVA ISTAT300 13
13 Line differential protection main-1 ABB REL531 14
14 Line differential protection main-2 SIEMENS 7SA522 16
15 Synchro check relay ABB RASC 17
16 Revenue Meter ELSTER A3 ALPHA 18
Annexure-: VA Requirement of Relay Page 2
Annexure-: VA Requirement of Relay Page 3
Annexure-: VA Requirement of Relay Page 4
Annexure-: VA Requirement of Relay Page 5
Annexure-: VA Requirement of Relay Page 6
Annexure-: VA Requirement of Relay Page 7
Annexure-: VA Requirement of Relay Page 8
Annexure-: VA Requirement of Relay Page 9
Annexure-: VA Requirement of Relay Page 10
Annexure-: VA Requirement of Relay Page 11
Annexure-: VA Requirement of Relay Page 12
Annexure-: VA Requirement of Relay Page 13
Annexure-: VA Requirement of Relay Page 14
Annexure-: VA Requirement of Relay Page 15
Annexure-: VA Requirement of Relay Page 16
Annexure-: VA Requirement of Relay Page 17
Annexure-: VA Requirement of Relay Page 18
ANNEXURE-3
SAUDI CABLE CATALOGUE
ANNEXURE-4
380kV GIS CT DATA
Ref.No. NA40034Ref.No. NA40034Ref.No. NA40034Ref.No. NA40034----D020D020D020D020 Date : Date : Date : Date : 9999 MayMayMayMay, 2006, 2006, 2006, 2006 Rev.2 5 Aug. 2009Rev.2 5 Aug. 2009Rev.2 5 Aug. 2009Rev.2 5 Aug. 2009 Rev.3 12 Aug.,2009Rev.3 12 Aug.,2009Rev.3 12 Aug.,2009Rev.3 12 Aug.,2009 Rev.4 18 Aug.,2009Rev.4 18 Aug.,2009Rev.4 18 Aug.,2009Rev.4 18 Aug.,2009
TECHNICAL SPECIFICATION FOR CTTECHNICAL SPECIFICATION FOR CTTECHNICAL SPECIFICATION FOR CTTECHNICAL SPECIFICATION FOR CT
ProjectProjectProjectProject : New 380/115kV ABU HADRIYAH BSP: New 380/115kV ABU HADRIYAH BSP: New 380/115kV ABU HADRIYAH BSP: New 380/115kV ABU HADRIYAH BSP Contract No.Contract No.Contract No.Contract No. : : : : 30531099/0030531099/0030531099/0030531099/00 SpecificationSpecificationSpecificationSpecification : 380kV 63kA 3150/2000A GIS: 380kV 63kA 3150/2000A GIS: 380kV 63kA 3150/2000A GIS: 380kV 63kA 3150/2000A GIS
1. Applicable Standard
- IEC 60044-1, IEC 60044-6
2. Ratings
- Symmetric short circuit (Ith) : 63kA rms
- Dynamic short circuit (Idyn) : 163.8kA peak
- Continuous thermal current rating factor : 2.0
1) GCB A810
Location Current Ratio
Specification Type
Adopted
TAP
Class Ual Rct
@75℃ Ial Burden Kssc K Rb
Bus-1
Side
1 3000-2500-2000-1500- 1250-1000-750/1A
2000/1A TPS >3700V <3.1Ω <75mA - 31.5 12.63 6.2 CT-1 50BF/A810
2 3000-2500-2000-1500- 1250-1000-750/1A
2000/1A TPS >3700V <3.1Ω <75mA - 31.5 12.63 6.2 CT-1 AL-FADHILI
LINE-2 SET-2
3 3000-2500-2000-1500- 1250-1000-750/1A
2000/1A TPS >3700V <3.1Ω <75mA - 31.5 12.63 6.2 CT-1 AL-FADHILI
LINE-2 SET-1
4 3000-2500-2000-1500- 1250-1000-750/1A
2500/1A 0.2 SF<5 - - 50VA - - - AL-FADHILI
LINE-2 MET.
Bus-2
Side
1 3000-2500-2000-1500- 1250-1000-750/1A
3000/1A TPS >5550V <4.65Ω <50mA - 21 18.95 9.3 CT-1 87B1/M1
2 3000-2500-2000-1500- 1250-1000-750/1A
3000/1A TPS >5550V <4.65Ω <50mA - 21 18.95 9.3 CT-1 87B1/M2
3 3000-2500-2000-1500- 1250-1000-750/1A
3000/1A TPS >5550V <4.65Ω <50mA - 21 18.95 9.3 CT-1 SPARE
NOTE:
1. CT-2 TYPE: Present design - 3000/1A Tap Rct<6.7ohm --- The CT is CT-2 type. If the CT will be used 2000/1A tap, Rct will be <4.65 ohm,
not <3.1ohm.
2. CT-1 TYPE: Present design - 2000/1A Tap Rct<3.1ohm --- The CT is CT-1 type. If the CT will be used 3000/1A tap, Rct will be <4.7ohm,
not <6.7ohm.
2) GCB A811
Location Current Ratio
Specification Type
Adopted
TAP
Class Ual Rct
@75℃ Ial Burden Kssc K Rb
Bus-1
Side
1 3000-2500-2000-1500- 1250-1000-750/1A
2000/1A TPS >3700V <3.1Ω <75mA - 31.5 12.63 6.2 CT-1 50BF/A811
2 3000-2500-2000-1500- 1250-1000-750/1A
2000/1A TPS >3700V <3.1Ω <75mA - 31.5 12.63 6.2 CT-1 MANIFA
LINE-2 SET-1
3 3000-2500-2000-1500- 1250-1000-750/1A
2000/1A TPS >3700V <3.1Ω <75mA - 31.5 12.63 6.2 CT-1 MANIFA
LINE-2 SET-2
4 3000-2500-2000-1500- 1250-1000-750/1A
3000/1A 0.2 SF<5 - - 60VA - - - MANIFA
LINE-2 MET.
Bus-2
Side
1 3000-2500-2000-1500- 1250-1000-750/1A
3000/1A TPS >5550V <4.65Ω <50mA - 21 18.95 9.3 CT-1 SPARE
2 3000-2500-2000-1500- 1250-1000-750/1A
2000/1A TPS >3700V <3.1Ω <75mA - 31.5 12.63 6.2 CT-1 AL-FADHILI
LINE-2 SET-1
3 3000-2500-2000-1500- 1250-1000-750/1A
2000/1A TPS >3700V <3.1Ω <75mA - 31.5 12.63 6.2 CT-1 AL-FADHILI
LINE-2 SET-2
4 3000-2500-2000-1500- 1250-1000-750/1A
2500/1A 0.2 SF<5 - - 50VA - - - AL-FADHILI
LINE-2 MET.
NOTE:
1. CT-2 TYPE: Present design - 3000/1A Tap Rct<6.7ohm --- The CT is CT-2 type. If the CT will be used 2000/1A tap, Rct will be <4.65 ohm,
not <3.1ohm.
2. CT-1 TYPE: Present design - 2000/1A Tap Rct<3.1ohm --- The CT is CT-1 type. If the CT will be used 3000/1A tap, Rct will be <4.7ohm,
not <6.7ohm.
3) GCB A812
Location Current Ratio
Specification Type
Adopted
TAP
Class Ual Rct
@75℃ Ial Burden Kssc K Rb
Bus-1
Side
1 3000-2500-2000-1500- 1250-1000-750/1A
3000/1A TPS >5550V <4.65Ω <50mA - 21 18.95 9.3 CT-1 87B2/M1
2 3000-2500-2000-1500- 1250-1000-750/1A
3000/1A TPS >5550V <4.65Ω <50mA - 21 18.95 9.3 CT-1 87B2/M2
3 3000-2500-2000-1500- 1250-1000-750/1A
3000/1A TPS >5550V <4.65Ω <50mA - 21 18.95 9.3 CT-1 SPARE
Bus-2
Side
1 3000-2500-2000-1500- 1250-1000-750/1A
2000/1A TPS >3700V <3.1Ω <75mA - 31.5 12.63 6.2 CT-1 50BF/A812
2 3000-2500-2000-1500- 1250-1000-750/1A
2000/1A TPS >3700V <3.1Ω <75mA - 31.5 12.63 6.2 CT-1 MANIFA
LINE-2 SET-1
3 3000-2500-2000-1500- 1250-1000-750/1A
2000/1A TPS >3700V <3.1Ω <75mA - 31.5 12.63 6.2 CT-1 MANIFA
LINE-2 SET-2
4 3000-2500-2000-1500- 1250-1000-750/1A
3000/1A 0.2 SF<5 - - 60VA - - - MANIFA
LINE-2 MET.
NOTE:
1. CT-2 TYPE: Present design - 3000/1A Tap Rct<6.7ohm --- The CT is CT-2 type. If the CT will be used 2000/1A tap, Rct will be <4.65 ohm,
not <3.1ohm.
2. CT-1 TYPE: Present design - 2000/1A Tap Rct<3.1ohm --- The CT is CT-1 type. If the CT will be used 3000/1A tap, Rct will be <4.7ohm,
not <6.7ohm.
ANNEXURE-4A
380kV GIS DATA SCHEDULE FROM TOSHIBA
ANNEXURE-5
SUBSTATION ELECTRICAL LAYOUT-PLAN
PROJECT: ABU-HADRIYAH 380/115 kV BSP ABU-HADRIYAH CONTRACT No. 3-083300.01ABUHADRIYAH 380/115kV BSP
TITLE: CT LEAD ROUTE LENGTH CALCULATION
DRAWING REFERENCE: ABU-HADRIYAH SUBSTATION ELECTRICAL LAYOUT -EA-0099121.02.03.0NOTE: CT LEAD LENGTH IS CONSIDERED AS 500 METERS ON CONSIDERABLY SAFER SIDE TO ACOUNT FOR ANY CIRCUIT CHANGES IN FUTURE. HENCE, CT LEAD LENGTH IS ESTIMATED AS 500 METERS FOR ALL BAYS CT SIZING CALCULATION.299273 400350CROSS BAY C3CROSS BAY C2 RPRP 230210 LENGTH AFTER TERMINATION (WITH 30% MARGIN) IN METERS325 LENGTH SELECTED IN METERS500RPSR.NO. CROSS BAY C4 250FROM BAY NO. TO RELAY PANEL LENGTH MEASURED IN METERS
ANNEXURE-6
RELAYING & METERING ONE LINE DIAGRAM
ANNEXURE-7
LINE PARAMETERS
ANNEXURE-8
M&I METROSIL CATALOGUE
ANNEXURE-9
380kV CVT DATA SCHEDULE