p r 11 hydro p.o. box 12400. st. john's. ni hydro place ... · documentation would be supplied...
TRANSCRIPT
Ai\p r I newfoundland labrador
11 hydro a nalcor energy company
Hydro Place. 500 Columbus Drive.
P.O. Box 12400. St. John's. NI
Canada A1B 4K7
t. 709.737.1400 f. 709.737.1800
www.n1h.nl.ca
December 17, 2014
The Board of Commissioners of Public Utilities
Prince Charles Building
120 Torbay Road, P.O. Box 21040
St. John's, Newfoundland & Labrador
A1A 5B2
Attention: Ms. Cheryl Blundon
Director Corporate Services & Board Secretary
Dear Ms. Blundon:
Re: Newfoundland and Labrador Hydro - the Board's Investigation and Hearing into Supply Issues and Power Outages on the Island Interconnected System: Supplementary Response in Relation to PUB-NLH-457 and PUB-NLH-458
In its responses to the Board's RFIs PUB-NLH-457 and PUB-NLH-458, Hydro indicated that additional
documentation would be supplied to the Board when the related work was completed. In this regard,
please find enclosed the original and 12 copies of the following:
a) Hydro's analysis of the impact of transmission line contingencies on system losses related to
alternate generation dispatches (re: PUB-NLH-457); and,
b) Two reports by Trans Grid Solutions Inc. related to the simulation of the Sunnyside Ti failure and
an investigation of the Western Avalon T5 transformer failure concerning whether or not
harmonics or system resonance were contributing factors to the system events of January, 2014
(re: PUB-NLH-458).
We trust the foregoing is satisfactory. If you have any questions or comments, please contact the
undersigned.
Yours truly,
NEWFOUNDLAND AND LABRADOR HYDRO
Tracey UPennell
Legal Counsel
TLP/jc
cc: Gerard Hayes — Newfoundland Power
Thomas Johnson — Consumer Advocate Paul Coxworthy — Stewart McKelvey Stirling Scales
Danny Dumaresque
ecc: Roberta Frampton Benefiel — Grand Riverkeeper Labrador
Engineering Support Services for:
Sunnyside Transformer T1 Fire
Newfoundland and Labrador Hydro
Attention:
Mr. Peter Thomas
Report R1335.01.00
PSCAD Investigation of the Sunnyside T1 Transformer Failure
Prepared by:
TransGrid Solutions Inc. 200 – 150 Innovation Dr.
Winnipeg, MB R3T 2E1
CANADA
www.transgridsolutions.com
Oct 5th, 2014
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
Disclaimer
This report was prepared by TransGrid Solutions Inc. (“TGS”), whose responsibility is limited to the scope of work
as shown herein. TGS disclaims responsibility for the work of others incorporated or referenced herein. This report
has been prepared exclusively for Newfoundland and Labrador Hydro and the project identified herein and must
not be reused or modified without the prior written authorization of TGS.
Revisions
Project Name: Sunnyside Transformer T1 Fire
Document
Title:
PSCAD Investigation of the Sunnyside T1 Transformer Failure
Document
Type:
Draft report
Document No.: R1335.01.00
Last Action
Date:
Oct 5th, 2014
Rev.
No.
Status Prepared By Checked By Date Comments
00 IFC D. Kell R. Kolt 05/10/14
01
Legend of Document Status:
Approved by Client ABC
Draft for Comments DFC
Issued for Comments IFC
Issued for Approval IFA
Issued for Information IFI
Returned for Correction RFC
Approval not Required ANR
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 2 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
Table of Contents
1. Introduction .............................................................................................................................................. 3 2. PSCAD Model Development ....................................................................................................................... 5
2.1 AC System model ......................................................................................................................................... 5
2.2 AC Transmission Lines .................................................................................................................................. 7
2.3 Power Transformers ..................................................................................................................................... 9
2.4 T5 Transformer at Sunny Side and T1 Transformer at Western Avalon .................................................... 10
2.5 PSCAD Model Benchmarking Against PSS/E............................................................................................... 12
3. Modeling of Fault...................................................................................................................................... 14
3.1 Transformer Fault ...................................................................................................................................... 14
4. Results ...................................................................................................................................................... 15 5. Conclusions and Recommendations .......................................................................................................... 19
List of Figures Figure 1‐1 Example of Low resolution waveforms ........................................................................................................ 3
Figure 2‐1 SLD of Newfoundland System ...................................................................................................................... 6
Figure 2‐2 Example Line Layout ..................................................................................................................................... 8
Figure 2‐3 Detailed Line Model ..................................................................................................................................... 9
Figure 2‐4 T1 ‐ SSD T5 ‐ WAV ....................................................................................................................................... 10
Figure 2‐5 Sunny Side T1 transformer model .............................................................................................................. 11
Figure 2‐6 SSD T1 Parameters ..................................................................................................................................... 12
Figure 4‐1 PSCAD Simulation ....................................................................................................................................... 15
Figure 4‐2 Actual Event ................................................................................................................................................ 15
Figure 4‐3 Transformer Currents ................................................................................................................................. 16
Figure 4‐4 Harmonics of Transformer (RMS) ............................................................................................................... 17
Figure 4‐5 Bay D'Espoir and TL237 measurements ..................................................................................................... 18
List of Tables
Table 2‐1 Frequency Dependent AC lines ...................................................................................................................... 7
Table 2‐2 SSD T5 ‐ WAV ............................................................................................................................................... 10
Table 2‐3 SCL Comparison ........................................................................................................................................... 12
Table 2‐4 Positive Sequence Impedance Comparison ................................................................................................. 13
Table 2‐5 Loadflow Comparison .................................................................................................................................. 13
Table 3‐1 AC system Fault Sequence ........................................................................................................................... 14
Table 3‐2 Internal Transformer Fault Sequence .......................................................................................................... 14
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 3 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
1. Introduction
This report presents the findings of the PSCAD simulation trying to recreate the Newfoundland T1 transformer
fault that occurred at 9:05am on January 4th, 2014.
The original scope of the project was to model the fault based on delivered comtrade data which records the
pertinent waveforms. Upon receipt of the data, the following was noticed:
1. The comtrade data delivered for times:
04/01/2014,13:13:09.000260
04/01/2014,10:05:34.000260
Both of which did not match the time of the fault. The comtrade data which had the same time stamp as the
fault was delivered as a pdf file, which is included in Appendix A.
2. The comtrade data had a very low resolution as shown in Figure 1‐1, which made it very hard to match to the
PSCAD simulation.
Figure 1-1 Example of Low resolution Waveforms
APSCAD model was created on the following information in order to try and recreate the fault based on the pdf
comtrade file.
2014Base‐Peak for Dyr.sav
PSS/E data file which represents the Newfoundland System conditions prior to the fault
Peak Case.dyr
PSS/E dynamics file
SSDTS T1 transformer nameplate, test data and transformer data (delivered as pdf files)
WAVTS T5 transformer nameplate, test data and transformer data (delivered as pdf files)
-100
-50
0
50
100
10 15 20 25 30
SSTSCF1C>1_A-230 KV TL202 A Phase Voltage(V)
Electrotek Concepts® TOP, The Output Processor®
Magnitude (
Mag
)
Time (ms)
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 4 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
AC Line geometric data based on past work performed by TGS. This included mutual coupling of
the lines the shared the same right‐of‐way.
AMEC report “Newfoundland and Labrador Hydro Transmission Availability” March 21, 2014.
This report gave the details of the sequence of events during the fault on January 4th.
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 5 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
2. PSCAD Model Development
2.1 AC System model
The following files provided by Newfoundland and Labrador Hydro (NLH) and were used as the base case to
develop the equivalent PSCAD model:
2014Base‐Peak for Dyr.sav
Peak Case. Dyr
The equivalent ac system in PSSE was converted to PSCAD. Since this study deals with a transient phenomenon as
a result of transformer failure at Sunnyside, the representation of the power system components with more
accuracy at higher frequencies than the fundamental frequency is crucial for a better analysis of the event.
Therefore the following changes were made to the converted case:
All the generators were represented with their associated dynamic data. That includes also
exciter, governor and power system stabilizers models (PSS)
A majority of the transmission lines surrounding the Sunnyside and Western Avalon were
modeled with frequency dependent line models according to the tower geometries and
conductor configurations
T1 transformer at Sunnyside and T5 transformer at Western Avalon based on the latest data
provided by NLH
Figure 2‐1 shows the single line diagram of the ac system used in this study. Please note that the whole case is not
shown in the diagram and only the main portion of the ac system surrounding Sunnyside and Western Avalon is
shown.
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 6 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
Figure 2-1 SLD of Newfoundland System
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 7 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
2.2 AC Transmission Lines
The major transmission line models in the PSCAD case which when originally converted from PSS/E, were
represented as pi‐sections and Bergeron line models
The Bergeron and pi‐section line representations are only adequate for studies that essentially require the correct
fundamental frequency impedance. However, in order to get a higher degree of accuracy, some of the lines near
the affected buses were replaced with frequency dependent line models.
Table 2‐1 lists of the lines that were modeled as frequency dependent lines.
Table 2-1 Frequency Dependent AC lines
From Bus# To Bus# From Bus# To Bus#
195229 195230 195167 195169
195222 195227 195169 195171
195221 195216 195171 195173
195216 195215 195173 195175
195221 195220 195222 195229
195220 195218 195227 195229
195215 195208 195229 195236
195215 195205 195229 195234
195205 195536 195234 195236
195205 195208 195236 195238
195622 195625 195221 195222
195625 195627 195152 195153
195124 195122 195153 195154
195122 195120 195155 195157
195120 195115 195157 195159
195115 195112 195152 195159
195112 195111 195620 195620
195209 195210 195621 195622
195208 195209 195112 195113
195205 195206 195600 196500
195500 195620 ‐ ‐
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 8 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
Figure 2‐2 shows an example of one of the more complicated line layouts, which includes the mutual coupling of
lines TL201, TL242 and TL218 and the mutual coupling of lines TL201 and TL217. Figure 2‐3 shows the detailed line
model for the lines TL201, TL242 and TL218.
Figure 2-2 Example Line Layout
N1
N2
N3
236
229
N4
234
238
SECTIO
NPI
2 CIRCUIT
1.0e-3 [ohm]
TL_201_218_242_1
TL201
TL242
TL_201_218_242_1
1
TL218
TL201
TL242
TL_201_218_242_1
1
TL218
1.0e-3 [ohm]
1.0e-3 [ohm]
TL_2490_229_1_1
1.0e-3 [ohm]
1.0e-3 [ohm]
1.0e-3 [ohm]
1.0e-3 [ohm]
TL201/T
L217
COU
PLED
PISECT
ION
COU
PLED
PISECT
ION
COU
PLED
PISECT
ION
1.0e-3 [ohm]
P = 260.6
Q =
12.79
V A
P = 166.1
Q =
-33.09
V A
P = 113.5
Q =
-59.98
V A
P = -185.2
Q =
-61.51
V A
P = -205.7
Q =
-68.45
V A
P = 111.8
Q =
-59.01
V A
P = 105.2
Q =
5.469
V A
P = 183.8
Q =
55.21
V A
==
=T
l218
==
=T
l242
==
=T
l217
P = -162
Q =
43.28
V A
==
=SZ
==
=SZ
==
=SZ
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 9 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
Figure 2-3 Detailed Line Model
2.3 Power Transformers
The power transformer models T5 at Sunny Side and T1 at Western Avalon are updated based on the following
data files received from NLH:
“WAVTS T5 nameplate.pdf”
“WAVTS T5 Test Report.pdf”
“Western Avalon‐T5.pdf”
“Sunnyside‐T1.pdf”
“SSDTS T1 Nameplate.pdf”
“SSDTS T1 test report.pdf”
2000.0 [ohm*m]Resistivity:
Analytical Approximation (Wedepohl)Analytical Approximation (Deri-Semlyen)Aerial:
Underground:Mutual: Analytical Approximation (LUCCA)
20Max. Order per Delay Grp. for Prop. Func.:
20Maximum Order of Fitting for Yc:
1.0E6 [Hz]Curve Fitting End Frequency:Curve Fitting Starting Frequency: 0.5 [Hz]
Frequency Dependent (Phase) Model Options
Maximum Fitt ing Error for Yc: 1.0 [%]
1.0 [%]Maximum Fitt ing Error for Prop. Func.:
Travel Time Interpolation:
100Total Number of Frequency Increments:
On
DisabledDC Correction:Passivity Checking: Disabled
12.57 [m]
6.7056 [m]
C1 C2 C3
Conductors: Grosbeak
Tower: TL201
0 [m]
G1
5 [m]
Ground_Wires: 1/2"HighStrengthSteel
21.6834 [m]
6.858 [m]
C4 C5 C6
Conductors: 804
Tower: TL242
-35.847 [m]
G1
5 [m]
Ground_Wires: 1/2"HighStrengthSteel 13.53 [m]
5.18 [m]
C7 C8 C9
Conductors: Plover
Tower: TL218
31.27 [m]
G1
5 [m]
Ground_Wires: 1/2"HighStrengthSteel
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 10 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
2.4 T5 Transformer at Sunny Side and T1 Transformer at Western Avalon
The T5 transformer at Sunnyside and the T1 transformer at Western Avalon is modeled based on the data
provided by NLH. Figure 2‐4 shows the PSCAD mode and Table 2‐2 shows the data used to model the
transformers.
Figure 2-4 T1 - SSD T5 – WAV
Table 2-2 SSD T5 - WAV
Name Tmva f YD1 YD2 YD3
T5 75 [MVA] 60.0 [Hz] Y Delta Y
T1 75.0 [MVA] 60.0 [Hz] Y Delta Y
Name Lead Xl12 Xl13 Xl23 Ideal
T5 Lags 0.1796 [pu] 0.0563 [pu] 0.1347[pu] Yes
T1 Lags 0.19677 [pu] 0.05578
[pu]
0.11371 [pu] Yes
Name NLL CuL Tap V1 V2
T5 0.000533 [pu] 0.00123335[pu] #1 230.0 [kV] 6.9
[kV]
T1 0.00057867 [pu] 0.00149133 [pu] #1 230 [kV] 6.9
[kV]
Name V3 Enab Sat Hys
T5 138.0 [kV] Yes Middle Jiles_Atherton
T1 138 [kV] Yes Middle Jiles_Atherton
1.0e6 [ohm]
#1
75 [MVA]230.0 [kV]/6.9 [kV]/138.0 [kV]
#3
#21.0e6 [ohm]
1.0e6 [ohm]
0.95
0.9625
1e-3 [ohm]
mid delta tert iary w inding is grounded. refer to xfr name plate
InT4_HInT4_L
#1
75.0 [MVA]230 [kV]/6.9 [kV]/138 [kV]
#3
#2
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 11 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
2.4.1.1 Sunny side Transformer Model Internal Fault Modeling
The T1 transformer model was modeled such that various internal faults can be applied to the transformer. Figure
2‐5 shows the T1 transformer model that was used to investigate a failure of the a‐phase winding to ground (short
to the tank) and a failure between the windings. Figure 2‐6 shows the SSD T1 parameters.
Figure 2-5 Sunny Side T1 Transformer Model
#2
#3
Tap
#1
A
B
C
N
B
A
C
N
N3
N1
Tap
G1G2
N2
Tap
Tap
Tap
#2
#3
Tap
#1
#2
#3
Tap
#1
Faulta1
+
R1
Ia
Ib
Ic #2
#3
Tap
#1
+
R1Faulta
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 12 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
Figure 2-6 SSD T1 Parameters
2.5 PSCAD Model Benchmarking Against PSS/E
Upon development of the ac network in PSCAD based on the equivalent developed model in PSS/E, it is required to
validate the PSCAD case against the equivalent case in PSSE. The validation was performed through comparison of
the short circuit levels at certain buses and the results of the load flow and power transfer at some selected
transmission lines.
The results of the comparison are shown in Table 2‐3, Table 2‐4 and Table 2‐5. The results compare very well
Table 2-3 SCL Comparison
Bus
Bus
Number
SCL (MVA)
% difference PSS/E Equivalent PSCAD
Western Avalon 195229 1997.30 1996.23 0.05
Sunny side 195222 2520.80 2469.65 2.03
Bay D Espoir 195221 2058.97 2014.47 2.16
Hollyrood 195234 2052.30 1998.49 2.62
Stony Brook 195216 3738.80 3601.09 3.68
Oxen Pond 195238 2164.00 2088.43 3.49
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 13 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
Table 2-4 Positive Sequence Impedance Comparison
Bus Bus
Number
Positive Impedance magnitude
Z+(Ohm)
Positive Impedance angle
Z+(degree)
PSS/E
Equivalent
PSCAD %
difference
PSS/E
Equivalent
PSCAD %
difference
Western Avalon 195229 26.75 26.5 0.93 66.83 66.52 0.46
Sunnyside 195222 21.62 21.42 0.93 70.4 70.23 0.24
Bay D Espoir 195221 26.51 26.26 0.94 69.71 69.79 ‐0.11
Hollyrood 195234 26.8 26.47 1.23 70.87 70.98 ‐0.16
Stony Brook 195216 14.79 14.69 0.68 82.73 82.66 0.08
Oxen Pond 195238 25.39 25.33 0.24 78.77 78.68 0.11
Table 2-5 Loadflow Comparison
From
Bus
Number
To Bus
Number
Line Real Power (MW) Reactive Power (MVAR)
PSS/E
Equivalent
PSCAD %
difference
PSS/E
Equivalent
PSCAD %
difference
195229 195234 TL217 109.5 113.1 ‐3.29% ‐60.5 ‐59.72 1.29%
195236 TL201 165.7 166.2 ‐0.30% ‐33.4 ‐33.06 1.02%
195222 TL203 ‐213.8 ‐216.3 ‐1.17% 56.8 56.1 1.23%
195227 TL237 ‐184.8 187.2 ‐1.30% 31 30.19 2.61%
195222 195227 TL207 214.1 217.1 ‐1.40% ‐110.2 ‐109.3 0.82%
195221 TL206 ‐272.0 ‐275.8 ‐1.40% 54.9 53.58 2.40%
195221 TL202 ‐273.3 ‐275.8 ‐0.91% 56 53.59 4.30%
195221 195216 TL204 57.4 55.28 3.69% ‐5.0 ‐5.3 ‐6.00%
195216 TL231 57.6 55.28 4.03% ‐5.0 ‐5.3 ‐6.00%
195220 TL234 ‐115 ‐114.6 0.35% ‐15.9 ‐16.68 ‐4.91%
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 14 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
3. Modeling of Fault
The modeling of the fault sequence was based on the AMEC report “Newfoundland and Labrador Hydro
Transmission Availability” March 21, 2014. The detailed sequence of events was given as shown Table 3‐1 below:
Table 3-1 AC System Fault Sequence Time delta‐T PSCAD Time event PSCAD Breaker Label
9:05:34.6 3.1
Fault Please see section 3.1
9:05:34.715 0.115 3.215 138kV Breaker L109T4 at SSD Opens CB1
9:05:34.753 0.038 3.253 138kV Breaker B3T4 at SSD Opens CB11
9:05:34.755 0.002 3.255 230kV Breaker B1L02 at SSD Opens CB2
9:05:34.786 0.031 3.286 138kV Breaker B2T1 at SSD Opens CB3
4 of 5 breakers for T1 now open, B1L03 does not open
9:05:36.719 1.933 5.219 Breaker L03L06 at SSD opens CB5
5.219 Breaker B1B2 at CBC Opens CB5
9:05:36.742 0.023 5.242 Breaker L03L06 at SSD opens CB6
9:05:36.820 0.078 5.32 Breaker L03L17 at WAV opens CB7
9:05:36.991 0.171 5.91 Breaker L01L03 at WAV opens CB8
3.1 Transformer Fault
In addition to the fault sequence modeled above, internal faults on the transformer were modeled. After various
faults were applied, Table 3‐2 shows the internal fault sequence that was found to give the closest results to the
transformer fault.
Table 3-2 Internal Transformer Fault Sequence PSCAD Time
event
3.1
Fault applied between phase A 230kV and 138 kV windings with a resistance of 50 ohms
3.15 Internal winding fault evolves into a 230kV to ground fault with a resistance of 50 ohms
3.2 Fault resistance decreases from 50 ohms to 25 ohms
4.0 A‐phase to ground fault evolves to a 3‐phase to ground fault with a resistance of 50 ohms
4.2 Resistance of 3‐phase faults decreases from 50 ohms to 25 ohms
4.7 Resistance of 3‐phase faults decreases from 50 ohms to 10 ohms
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 15 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
4. Results
Appendix 2 shows the results for the fault. As it is unknown if this is the actual fault that was experienced by the
transformer, comparing values would not be useful. Of more use is comparing the trend. What is obvious right
away is that as breaker B1L03 did not open, the fault on the transformer was being sustained as shown in Figure
4‐1. Referring to Figure 4‐2, the neutral current in T1 extinguished before the breakers cleared the fault. Based on
the simulations, it seems more likely that the CT or the cabling was damaged during the event which led to a loss
of measurement.
Figure 4-1 PSCAD Simulation
Figure 4-2 Actual Event
Figure 4‐3shows the currents in the actual windings of the failed transformer during the fault.
Figure 4‐4shows the harmonics spectrum in the transformer during the fault.
x 0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
-2.00
-1.50
-1.00
-0.50
0.00
0.50
1.00
1.50
2.00
y
T1 High side Neutral Current
-2.00
-1.50
-1.00
-0.50
0.00
0.50
1.00
1.50
2.00
y
T4 High side Neutral Current
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 16 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
Figure 4-3 Transformer Currents
x 0.00 0.25 0.50 0.75 1.00 1.25 1.50 1.75
-1.25
1.25
y
Phase A 230kV Winding Current
-15.0 -10.0 -5.0 0.0 5.0
10.0 15.0
y
Phase A 6.9kV Winding Current
-1.50 -1.00 -0.50 0.00 0.50 1.00 1.50
y
Phase A 138kV Winding Current
-0.80 -0.60 -0.40 -0.20 0.00 0.20 0.40 0.60
y
Phase B 230kV Winding Current
-15.0 -10.0 -5.0 0.0 5.0
10.0 15.0
y
Phase B 6.9kV Winding Current
-0.60 -0.40 -0.20 0.00 0.20 0.40 0.60
y
Phase B 138kV Winding Current
-0.50
0.50
y
Phase C 230kV Winding Current
-15.0 -10.0 -5.0 0.0 5.0
10.0 15.0
y
Phase V 6.9kV Winding Current
-0 80-0.60 -0.40 -0.20 0.00 0.20 0.40 0.60
y
Phase C 138kV Winding Current
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 17 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
Figure 4-4 Harmonics of Transformer (RMS)
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 18 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
Figure 4‐5 shows the P, Q and speed of the Bay D’Espoir unit 1 and the current in line TL237 and the Western
Avalon bus voltage. As indicated in the AMEC report, and confirmed here, the ac system starts to go unstable for
this fault.
Figure 4-5 Bay D'Espoir and TL237 measurements
G_195001_0_1_DYR,Measure,P2 : Graphs
x 0.00 0.50 1.00 1.50 2.00 2.50 3.00
0.990
1.000
1.010
1.020
1.030
1.040
1.050
1.060
(pu
)
Wpu
-20
0
20
40
60
80
100
(M
W)
P
-60 -40 -20
0 20 40 60 80
100
(M
VAR)
Q
-2.00 -1.50 -1.00 -0.50 0.00 0.50 1.00 1.50 2.00
y
I237
-250 -200 -150 -100 -50
0 50
100 150 200 250
V_WA
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 19 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
5. Conclusions and Recommendations
Although the exact fault has not been reproduced here, a fairly comparable one has been simulated. It is evident
that due to the long duration it took to clear the transformer fault, the transformer experienced very high
currents, with nearly 2.5kA flowing for the duration of the fault.
TGS recommendeds that once more details are available about the actual fault of the transformer, that the model
be updated and simulations rerun to recreate what happened. This new information will give further confidence in
the developed model and allow for future studies to be done either as a system strengthening exercise or for a
post‐mortem on future faults.
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 20 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
6. Appendix 1 – Actual TFR Traces
Reference: PUB-NLH-458 Atth 2
Transcan DFR : SUNNYSIDE Terminal Station SSTSCF1C.X0V Jan/04/2014 09:05:34 (file)All Channels - 0X, 3840Hz Page 1 of 2
0.000 ms 1791.667 ms
202-Va202-Vb202-Vc202-Ia202-Ib202-Ic202-In203-Va203-Vb203-Vc203-Ia203-Ib203-Ic203-InT1-InT4-In206-Va206-Vb206-Vc206-Ia206-Ib206-Ic206-In207-Va207-Vb207-Vc207-Ia207-Ib207-IcB2-VaB2-VbB2-Vc94T186T1203-94A1203-94B1203-94C1203-94L1203-94L2203-P1P2
Reference: PUB-NLH-458 Atth 2
Transcan DFR : SUNNYSIDE Terminal Station SSTSCF1C.X0V Jan/04/2014 09:05:34 (file)All Channels - 0X, 3840Hz Page 2 of 2
Trace Label Name Scale Units/Division1 202-Va 230 KV TL202 A Phase Voltage 1.00 72177.652 V2 202-Vb 230 KV TL202 B Phase Voltage 1.00 72458.470 V3 202-Vc 230 KV TL202 C Phase Voltage 1.00 72601.507 V4 202-Ia TL202 A Phase Current 5.00 338.114 A5 202-Ib TL202 B Phase Current 5.00 338.290 A6 202-Ic TL202 C Phase Current 5.00 339.371 A7 202-In TL202 Neutral Current 15.00 113.019 A8 203-Va 230 KV TL203 A Phase Voltage 1.00 72423.934 V9 203-Vb 230 KV TL203 B Phase Voltage 1.00 72506.562 V
10 203-Vc 230 KV TL203 C Phase Voltage 1.00 72394.188 V11 203-Ia TL203 A Phase Current 5.00 337.960 A12 203-Ib TL203 B Phase Current 5.00 338.712 A13 203-Ic TL203 C Phase Current 5.00 338.641 A14 203-In TL203 Neutral Current 15.00 112.692 A15 T1-In T1 Neutral Current 2.00 1059.220 A16 T4-In T4 Neutral Current 2.00 1059.457 A17 206-Va 230KV TL206 A Phase Voltage 1.00 72296.314 V18 206-Vb 230KV TL206 B Phase Voltage 1.00 72600.926 V19 206-Vc 230KV TL206 C Phase Voltage 1.00 72753.172 V20 206-Ia TL206 A Phase Current 5.00 339.398 A21 206-Ib TL206 B Phase Current 5.00 338.909 A22 206-Ic TL206 C Phase Current 5.00 338.978 A23 206-In TL206 Neutral Current 15.00 113.283 A24 207-Va 230KV TL207 A Phase Voltage 1.00 72562.495 V25 207-Vb 230KV TL207 B Phase Voltage 1.00 72516.289 V26 207-Vc 230KV TL207 C Phase Voltage 1.00 72466.927 V27 207-Ia TL207 A Phase Current 5.00 339.563 A28 207-Ib TL207 B Phase Current 5.00 338.912 A29 207-Ic TL207 C Phase Current 5.00 340.012 A30 B2-Va 138 KV B2 A Phase Voltage 1.00 43573.561 V31 B2-Vb 138 KV B2 B Phase Voltage 1.00 43518.666 V32 B2-Vc 138 KV B2 C Phase Voltage 1.00 43444.008 V33 94T1 94T1 N/A N/A34 86T1 86T1(NC) N/A N/A35 203-94A1 TL203 94A1X N/A N/A36 203-94B1 TL203 94B1X N/A N/A37 203-94C1 TL203 94C1X N/A N/A38 203-94L1 TL203 94L1 N/A N/A39 203-94L2 TL203 94L2 N/A N/A40 203-P1P2 TL203 21P1/P2 N/A N/A
Reference: PUB-NLH-458 Atth 2
Newfoundland and Labrador Hydro Sunnyside Transformer T1 Fire
PSCAD Investigation of the Sunnyside T1 Transformer Failure
R1335.01.00 21 Oct 5th, 2014
© TransGrid Solutions Inc, 2014
7. Appendix 2 – Simulated Traces
Reference: PUB-NLH-458 Atth 2
Analog Graph
x 0.00 0.50 1.00 1.50 2.00 2.50 3.00
-300
-200
-100
0
100
200
300 y
V202:1
-500 -400 -300 -200 -100
0 100 200 300 400
y
V202:2
-400 -300 -200 -100
0 100 200 300 400
y
V202:3
-2.50 -2.00 -1.50 -1.00 -0.50 0.00 0.50 1.00 1.50 2.00 2.50
y
I202:1
-2.50 -2.00 -1.50 -1.00 -0.50 0.00 0.50 1.00 1.50 2.00 2.50
y
I202:2
-3.0
-2.0
-1.0
0.0
1.0
2.0
3.0
y
I202:3
-200 -150 -100
-50 0
50 100 150 200
y
V203:1
-250 -200 -150 -100
-50 0
50 100 150 200 250
y
V203:2
-200 -150 -100
-50 0
50 100 150 200
y
V203:3
Reference: PUB-NLH-458 Atth 2
Analog Graph
x 0.00 0.50 1.00 1.50 2.00 2.50 3.00
-4.0 -3.0 -2.0 -1.0 0.0 1.0 2.0 3.0
yI203:1
-3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 4.0
y
I203:2
-3.0 -2.0 -1.0
0.0 1.0 2.0 3.0
y
I203:3
-2.00 -1.50 -1.00 -0.50 0.00 0.50 1.00 1.50 2.00
y
T1 High side Neutral Current
-2.00 -1.50 -1.00 -0.50 0.00 0.50 1.00 1.50 2.00
y
T4 High side Neutral Current
-300 -200 -100
0 100 200 300
y
V206:1
-500
400
y
V206:2
-400 -300 -200 -100
0 100 200 300 400
y
V206:3
-2.50
2.50
y
I206:1
-2.50
2.50
y
I206:2
-3.0 -2.0 -1.0 0.0 1.0 2.0 3.0
y
I206:3
Reference: PUB-NLH-458 Atth 2
Analog Graph
x 0.00 0.50 1.00 1.50 2.00 2.50 3.00
-300
-200
-100
0
100
200
300 y
V207:1
-500 -400 -300 -200 -100
0 100 200 300 400
y
V207:2
-400 -300 -200 -100
0 100 200 300 400
y
V207:3
-2.00 -1.50 -1.00 -0.50 0.00 0.50 1.00 1.50 2.00
y
I207:1
-2.00 -1.50 -1.00 -0.50 0.00 0.50 1.00 1.50 2.00
y
I207:2
-2.00 -1.50 -1.00 -0.50 0.00 0.50 1.00 1.50 2.00
y
I207:3
-5.0 -4.0 -3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 4.0 5.0
y
SSD T1 phase A
-5.0 -4.0 -3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 4.0 5.0
y
SSD T1 phase B
-5.0 -4.0 -3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 4.0 5.0
y
SSD T1 phase C
Reference: PUB-NLH-458 Atth 2
x 0.00 0.25 0.50 0.75 1.00 1.25 1.50 1.75
-1.25 -1.00 -0.75 -0.50 -0.25 0.00 0.25 0.50 0.75 1.00 1.25
yPhase A 230kV Winding Current
-15.0
-10.0
-5.0
0.0
5.0
10.0
15.0
y
Phase A 6.9kV Winding Current
-1.50
-1.00
-0.50
0.00
0.50
1.00
1.50
y
Phase A 138kV Winding Current
-0.80 -0.60 -0.40 -0.20 0.00 0.20 0.40 0.60
y
Phase B 230kV Winding Current
-15.0
-10.0
-5.0
0.0
5.0
10.0
15.0
y
Phase B 6.9kV Winding Current
-0.60
-0.40
-0.20
0.00
0.20
0.40
0.60
y
Phase B 138kV Winding Current
-0.50 -0.40 -0.30 -0.20 -0.10 0.00 0.10 0.20 0.30 0.40
y
Phase C 230kV Winding Current
-15.0
-10.0
-5.0
0.0
5.0
10.0
15.0
y
Phase V 6.9kV Winding Current
-0.80 -0.60 -0.40 -0.20 0.00 0.20 0.40 0.60
y
Phase C 138kV Winding Current
Reference: PUB-NLH-458 Atth 2
Analog Graph
x 0.00 0.50 1.00 1.50 2.00 2.50 3.00
-0.06m
-0.04m
-0.02m
0.00
0.02m
0.04m
0.06my
Imaga
-2.00
-1.50
-1.00
-0.50
0.00
0.50
1.00
1.50
2.00
y
Fluxa
-0.35m
-0.30m
-0.25m
-0.20m
-0.15m
-0.10m
-0.05m
0.00
0.05m
0.10m
0.15m
y
Imagb
-2.00
-1.50
-1.00
-0.50
0.00
0.50
1.00
1.50
2.00
y
Fluxb
-0.3m
-0.2m
-0.1m
0.0
0.1m
0.2m
0.3m
y
Imagc
-2.00
-1.50
-1.00
-0.50
0.00
0.50
1.00
1.50
2.00
y
Fluxc
Reference: PUB-NLH-458 Atth 2
Analog Graph
x 0.00 0.50 1.00 1.50 2.00 2.50 3.00
0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50
yIT1_H_FFTa:1
0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70
y
IT1_H_FFTa:2
0.000 0.050 0.100 0.150 0.200 0.250 0.300 0.350 0.400
y
IT1_H_FFTa:3
0.000
0.050
0.100
0.150
0.200
y
IT1_H_FFTa:4
0.000
0.050
0.100
0.150
0.200
y
IT1_H_FFTa:5
0.000 0.025 0.050 0.075 0.100 0.125 0.150 0.175 0.200
y
IT1_H_FFTa:6
0.000 0.020 0.040 0.060 0.080 0.100 0.120 0.140
y
IT1_H_FFTa:7
0.000 0.020 0.040 0.060 0.080 0.100 0.120 0.140
y
IT1_H_FFTa:8
0.000
0.020
0.040
0.060
0.080
0.100
y
IT1_H_FFTa:9
0.000
0.020
0.040
0.060
0.080
0.100
y
IT1_H_FFTb:10
Reference: PUB-NLH-458 Atth 2