For Electric Drive Systems[PSpice Version]

All Rights Reserved Copyright (C) Bee Technologies Inc. 2012 1

Concept KitModeling of 3-Phase AC Motor Drive Simulation

Contents

Slide #

1. Modeling of 3-Phase AC Motor Model

1.1 Manufacturer Specification.........................................................................................................

1.2 Torque and Back-EMF...............................................................................................................

1.3 Simplified 3-Phase AC Motor Model.........................................................................................

1.4 The 3-Phase AC Motor Equivalent Circuit.................................................................................

1.5 Parameter Settings.....................................................................................................................

2. Simulation Circuit of 3-Phase AC Motor Model................................................................................

2.1 Phase Current Characteristics Under Load Variation................................................................

2.2 Back-EMF Characteristics Under Load Condition.....................................................................

2.3 Speed and Torque Characteristics At 140Arms........................................................................

2.4 Power Output and Efficiency Characteristics At 140Arms.........................................................

Appendix A: Measured Point of Simulation Circuit (1/2)...........................................................

Appendix A: Measured Point of Simulation Circuit (2/2)...........................................................

Appendix B: Evaluation Text......................................................................................................

Appendix C: Gate Signal for Six-Step Control...........................................................................

Appendix D: 3-Phase AC Motor Model Text (1/2).....................................................................

Appendix D: 3-Phase AC Motor Model Text (2/2).....................................................................

Appendix E: Simulation Settings................................................................................................

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

2All Rights Reserved Copyright (C) Bee Technologies Inc. 2012

Motenergy, Inc (ME0913)

Motor Electrical Parameters

• Operating Voltage Range..........................0 – 72 VMAX

• Rated Continuous Current........................140 Arms

• Peak Stalled Current.................................400 Arms

• Voltage Constant.......................................50 RPM/V

• Phase Resistance (L-L).............................0.0125 Ω

• Phase Inductance......................................105uH at 120Hz, 110uH at 1kHz

• Maximum Continuous Power Rating……..17KW at 102VDC Battery Voltage

14.3KW at 84VDC Battery Voltage

12KW at 72VDC Battery Voltage

Motor Mechanical Parameters

• Rated Speed.............................................3000 RPM

• Maximum Speed.......................................5000 RPM

• Rated Torque............................................288 Lb-in

• Torque Constant.......................................1.6 Lb-in/A

1.1) Manufacturer Specification

All Rights Reserved Copyright (C) Bee Technologies Inc. 2012 3

• The Torque are defined by :

At 140Arms (Rated Continuous Current)

KT = 1.6 Lb-in/A

Tphe = 1.6 140 = 224Lb-in

Te = 224*3= 672Lb-in

• The Back-EMF are defined by :

At 5000 RPM (Maximum Speed)

Ephe ≈ VBAT (In an ideal motor, R and L are zero)

Ephe = 102V

KE = Ephe /ωm = 102 / 5000

KE ≈ 0.02V/RPM

1.2) Torque and Back-EMF

All Rights Reserved Copyright (C) Bee Technologies Inc. 2012 4

wTw

vTv

uTu

IKT

IKT

IKT

mEw

mEv

mEu

KE

KE

KE

phe : u, v, w

Vphe : Phase voltage applied from inverter to motor

VAC : Operating voltage range (Maximum voltage)

VBAT : DC Voltage applied from battery

Iphe : Phase current

Tphe : Electric torque produced by u, v, w phase

Te : Electric torque produced by motor

Ephe : Phase Back-EMF

KE : Back-EMF constant KT : Torque constant

ωm : Angular speed of rotor

1 Pound Inch equals 0.11 Nm

TwTvTueT

(1)

(2)

(3)

1.3) Simplified 3-Phase AC Motor Model

All Rights Reserved Copyright (C) Bee Technologies Inc. 2012 5

L 11 2

B E M F 1R 1

L 21 2

B E M F 2R 2

L 31 2

B E M F 3R 3

N 0

U

V

W

Phase Resistance (L-L) : 0.0125ΩPhase Inductance :

105uH: 110uH

Frequency Response

105uH

110uH

Fig.2 Phase-to-GroundFig. 1 Scheme of the 3-Phase Model

1.4) The 3-Phase AC Motor Equivalent Circuit

• This figure shows the equivalent circuit of AC motor model that includes the |Z|-frequency part ,Back-EMF voltage part ,and Mechanical part.

• The Back-EMF voltage is the voltage generated across the motor's terminals as the windings move through the motor's magnetic field.

All Rights Reserved Copyright (C) Bee Technologies Inc. 2012 6

|Z| - Frequency Back-EMF Voltage

Mechanical part

Fig. 3 Three-Phase AC Motor Equivalent Circuit

PARAMETERS:

KT = 1.6KE = 0.02

LL = 105URLL = 0.0125

PARAMETERS:LOAD = 140

U3

1 2S

PT

Q

emf_u

0

IN+IN-

OUT+OUT-

eu

0

IN+IN-

OUT+OUT-

0

IN+IN-

OUT+OUT-

0

lim_v

IN+IN-

OUT+OUT-

0

0

IN+IN-

OUT+OUT-

lim_w

0

emf_vev

emf_u

-+ +

-

E2

0emf_v

emf_wew-+ +

-

E3

emf_w0

n1

tu

0

tv

0

tw

N0

n2

U

n3W

V

Vu

speed

IN+IN-

OUT+OUT-

0

mul

Vv

torque

Vw

-+ +

-

E1

0

0

IN+IN-

OUT+OUT-

0

IN+IN-

OUT+OUT-

0

lim_u

sp_v

sp_u

sp_usp_w

sp_wsp_v

U11 2

SP

TQ

U2

1 2S

PT

Q

1.5) Parameters Settings

All Rights Reserved Copyright (C) Bee Technologies Inc. 2012 7

LOAD : Load current each phase of motor [Arms]– e.g. LL = 125Arms, 140Arms, or 400Arms

LL : Phase inductance [H]– e.g. LL = 10mH, 100mH, or 1H

RLL : Phase resistance (Phase-to-phase) [Ω]– e.g. RLL = 10mΩ, 100mΩ, or 1Ω

KE : Back-EMF constant [V/RPM]– e.g. KE= 0.01, 0.05, or 0.1

KT : Torque constant [Lb-in/A]– e.g. KT= 0.1, 0.5, or 1

1 Pound Inch equals 0.11 Nm

Model Parameters:

Fig. 4 Symbol of 3-Phase Induction Motor

• From the 3-Phase Induction Motor specification, the model is characterized by setting parameters LL, RLL, KE, KT and LOAD.

M N 0

U 1M E 0 9 1 3

L L = 1 0 5 U

L O A D = 1 4 0K T = 1 . 6K E = 0 . 0 2R L L = 0 . 0 1 2 5

1

2

3

4

2) Simulation Circuit of 3-Phase AC Motor Model

All Rights Reserved Copyright (C) Bee Technologies Inc. 2012 8

• Fig.5 Analysis of motor operation powered by alternating voltage variation involves using the model of three-phase induction motor.

N 0N 0

R U

R V

R W

U 2G D R VU

D

UP

VDVP

WD

WP

RU, RV, RW: 173.75m

U P U D V DV P W P W D

V 11 0 2 V +

-

+

-

S 1 D 1D M O D _ 0 1

+

-

+

-

S 2 D 2D M O D _ 0 1

U P

U D

0

0

+

-

+

-

S 3

M N 0

U 1M E 0 9 1 3

L L = 1 0 5 U

L O A D = 1 4 0K T = 1 . 6K E = 0 . 0 2R L L = 0 . 0 1 2 5

1

2

3

4

D 3D M O D _ 0 1

+

-

+

-

S 4 D 4D M O D _ 0 1

V P

V D

0

0

+

-

+

-

S 5 D 5D M O D _ 0 1

+

-

+

-

S 6 D 6D M O D _ 0 1

W P

W D

0

0

U

0

V

W

V 21 0 2 V

2.1) Phase Current Characteristics Under Load Variation - Simulation Results

All Rights Reserved Copyright (C) Bee Technologies Inc. 2012 9

Fig. 6 Current Characteristics under load Condition

Time

0s 500msI(RU)/SQRT(2)

-500A

0A

500A Time

0s 500msI(RU)/SQRT(2)

-500A

0A

500A

Time

0s 500msI(RU)/SQRT(2)

-500A

0A

500A

Load 50Arms

Load 140Arms

Load 200Arms

Reference of Phase U

Time

0s 500msV(X_U1.EU)

-200V

-100V

0V

100V

200V Time

0s 500msV(X_U1.EU)

-200V

-100V

0V

100V

200V Time

0s 500msV(X_U1.EU)

-200V

-100V

0V

100V

200V

2.2) Back-EMF Characteristics Under Load Condition - Simulation Results

All Rights Reserved Copyright (C) Bee Technologies Inc. 2012 10

Fig. 7 Back-EMF Characteristics under load Condition

Load 50Arms

Load 140Arms

Load 200Arms

Reference of Phase U

Time

0s 500msV(X_U1.tu)

0V

0.5KV

1.0KV

(446.486m,223.728)

V(X_U1.speed)0V

1.0KV

2.0KV

3.0KV

4.0KV

SEL>>

(464.146m,3.2311K)

2.3) Speed and Torque Characteristics At 140Arms- Simulation Results

All Rights Reserved Copyright (C) Bee Technologies Inc. 2012 11

Fig. 8 Speed and Torque Characteristics at Load=140Arms

The Load 140(Arms) is Rated Continuous Current

Tphe: Electric torque produced by each phase

RPM

Lb-in

Reference of Phase U

Time

0.5s 1.0s100*( (RMS(V(U,N0))*RMS(I(RU))) / (RMS(V(RU:1,N0))*RMS(I(RU))) )

0

50

100

(962.500m,81.941)

RMS(V(RU:1,N0))*RMS(I(RU))0W

10KW

20KW

SEL>>

(960.616m,13.662K)

2.4) Power Output and Efficiency Characteristics At 140Arms- Simulation Results

All Rights Reserved Copyright (C) Bee Technologies Inc. 2012 12

Fig. 9 Power Output and Efficiency Characteristics at Load=140Arms

At Load=140Arms, Power Output ≈ 13.7 [KW]

At Load=140Arms, Efficiency ≈ 82 [%]

Watt

[%]

Reference of Phase U