EE631 – Spring 2005 1

ECE631/EE631QLecture 15: Switch Level Inverter

Modeling

S.D.Sudhoff

Purdue University

EE631 – Spring 2005 2

IM Overview

ini

invinr

inC

aLi

bLi

cLi

Lacr

Lacr

Lacr

acL

acL

acL

Cacr

Cacr

Cacr

acC

acC

acC

aOi

bOi

abOv

*eqLi

*edLi

e

*eqOv*edOv

e

aLi

bLi

VoltageController

CurrentController Voltage

ControllerVoltage

Controller

cbOv

EE631 – Spring 2005 3

Objectives Today

• Develop switch level inverter model that includes losses

• Based on paper, “IGBT and PN Junction Diode Loss Modeling For System Simulations ” by B. Cassimere, S. Sudhoff, B. Cassimere, M. Swinney to be presented at the 2005 IEMDC

EE631 – Spring 2005 4

Inverter Phase Leg

-

+

+-xrv

xdci

dcv xsixus

xls

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Conduction Losses

xc

bx

x

bx

x

i

i

i

ixxcd xbav

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Switching Losses: Test Scenario

+

_

U

SorensenDHP 400Variable

DC PowerSupply

Tektronix 3450Digital

Oscilloscope500MHz 2Gs/s

Tektronix AM5030Current Probe Amplifier

Tektronix PS200Voltage Differential

Tektronix AM5030Current Probe Amplifier

Tektronix PS200Voltage Differential

Tektronix A6302Current Loop Probes

Devices Under Test (DUTs)

+

_

_

+

BX

BU

EU

EX

(GU)

(GX)

tv

ti

dv

td ii

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Unprocessed Waveforms

EE631 – Spring 2005 8

Filtered IGBT Turn On Waveforms

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Turn On Energy And Loss

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Energy Loss Summary

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Approaches to Loss Incorporationinto Simulation Model

• Physics Based Device Model

• Behavior Based Device Model

• Other

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xrv

xdci

lxP

ldo fft

xsi

dcxsvi

xus0

0

0

0

Initial Conduction Interval

SwitchingInterval 1

SwitchingInterval 2

FinalConduction Interval

Case 1 - Upper IGBT to lower diode

tcddc vv

dcdv

etdt

Case 1: Upper IGBT to Lower Diode

EE631 – Spring 2005 13

xrv

xdci

lxP

x si

dcxs vi

l d o nt

xus

0

0

0

0

I n it ia l C o n d u c t io n I n te r v a l

S w itc h in gI n ter v a l 1

S w itc h in gI n ter v a l 2

F in a lC o n d u c t io n I n te r v a l

C ase 2 - U pper d iode to low er IG B T

dcddc vv tcdv

e d tt

Case 2: Upper Diode to Lower IGBT

EE631 – Spring 2005 14

xrv

xdci

lxP

x si

dcxs vi

ld o nt

0

0

0

0

S w itc h in gI n ter v a l 2

I n it ia l C o n d u c t io n I n te r v a l

S w itc h in gI n ter v a l 1

F in a lC o n d u c t io n I n te r v a l

x us

C ase 3 - Low er d iode to upper IG B T

tcddc vv

e d tt

dcdv

Case 3: Lower Diode to Upper IGBT

EE631 – Spring 2005 15

xrv

xdci

lxP

ldofft

x si

dcxsvi0

0

0

0

SwitchingInterval 2

Initial Conduction Interval

SwitchingInterval 1

FinalConduction Interval

xus

Case 4 - Lower IGBT to upper diode

dcddc vv

etdt

tcdv

Case 4: Lower IGBT to Upper Diode

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Calculation of Switching Times

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Switching Times

yyyyh

by

xs

g

dcb

dcy

e

by

xsy

c

dcb

dcyyy i

i

v

vf

i

id

v

vbat

EE631 – Spring 2005 18

Model SummaryTable III. Model Summary

Time Period Duration xrv xdci

Conduction Interval

0xsi - tcddc vv xsi

1xus 0xsi - dcddc vv dcddc vv

0xsi - dcdv 0

0xus 0xsi - tcdv 0

Switching Interval 1

0xsi ldofft tcddc vv xsi

1xus 0xsi ldont dcddc vv dcddc vv

0xsi ldont dcdv 0

0xus 0xsi ldofft tcdv 0

Switching Interval 2

Case 1 etdt tcddc vv xsi

Case 2 edtt dcddc vv 0

Case 3 edtt 0 xsi

Case 4 etdt dcddc vv 0

EE631 – Spring 2005 19

Model Parameters

• Fuji 6MBI30L-060

• Fuji Electric EXB840

• Gate resistance of 85 • On voltage of 15V

• Off voltage of -5V

EE631 – Spring 2005 20

Model Parameters

Table 2. Switching Parameters.

Transistor Diode Units

bxi 30 30 A

dcxv 600 600 V

ya 7.303x 10-7 3.951 x 10-7 s

yb -1.289 x 10-6 -3.500 x 10-6 s

yc 1.454 x 10-1 1.362 -

yd -1.467x 10-6 4.660 x 10-7 s

ye 1.623 x 10-1 1.480 -

yf 3.645 x 10-6 3.643 x 10-6 s

yg 5.762 x 10-2 1.844 -

yh 5.646 x 10-2 -4.142x 10-2 -

ldont 3.2 x 10-6 1.6 x 10-6 s

ldofft 1.6 x 10-6 3.2 x 10-6 s

bxi xaxbxc

Table I. Conduction Loss Parameters.

Transistor Diode Units

bxi 30 30 A

xa 2.01 x 10-4 .270 V

xb 3.56 1.45 V

xc 0.257 0.136 -

EE631 – Spring 2005 21

Model Predictions

EE631 – Spring 2005 22

Thermal Effects