A HighA High--efficiency Compact SiCefficiency Compact SiC--based Power based Power Converter SystemConverter System

Timothy LinTimothy Lin

Aegis Technology Inc. Aegis Technology Inc. 3300 A Westminster Ave., Santa Ana, CA 927033300 A Westminster Ave., Santa Ana, CA 92703

DOE STTR Phase II (DEDOE STTR Phase II (DE--FG02FG02--05ER86234)05ER86234)Research Institute: Research Institute: The University of Tennessee, KnoxvilleThe University of Tennessee, Knoxville

DoE Peer Review 2008, September 29 DoE Peer Review 2008, September 29 -- 30,Washington, D.C. 30,Washington, D.C.

Funded by the Energy Storage Systems Program of the U.S. Department Of Energy (DOE/ESS) through the Small Business Technology Transfer (STTR) program and managed by Sandia National Laboratories (SNL). Sandia is a multi-program laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy’s National Nuclear Security Administration, under contract DE-AC04-94AL85000.

AcknowledgementAcknowledgement

• This project is sponsored by the Energy Storage Program, U.S. Department of Energy.

• DOE STTR project Phase I and ongoing Phase II (DE(DE--FG02FG02--05ER86234).05ER86234).

• Special thanks to Dr. Imre Gyuk, Manager, Energy Storage Program, U.S. Department of Energy, and Dr. Stanley Atcitty, Technical supervisor, Sandia National Laboratories.

Significance and Challenges

• Advantages of SiC power electronics– SiC technology will enable less conduction loss, higher

temperature operation (>175°C) and high frequency operation(100 to 500kHz).

– Smaller volume, lighter weight, higher power density.– Higher efficiency.

• Challenge issues– Specially designed drive circuit because of its switching ON

– OFF characteristics (normally ON for commercial SiC switch, JFETs).

– High temperature packaging. – Limited current capability of SiC devices needing the

paralleling of multiple devices.

ObjectiveObjective

• Develop a high-efficiency compact power inverter based on SiC- based semiconductor technology

– High efficiency, small size, and light weight.– High power density, high temperature, and high frequency.– Scalable current ratings and power levels.

• Address associated technical issues and supporting technologies

– Design, modeling and simulation.– Power modules by paralleling multiple SiC devices.– High-temperature package and thermal management. – High-frequency gate driver suitable for SiC power devices.

• Integrate the technologies for demonstration/test of a SiC inverter that can operate at high junction/environment temperatures

– Analyze the benefits of using SiC power devices in a systematic level.

– Explore potential applications (e.g. electric energy storage).

SiC diodes/ JFETs

Dynamic/Static testing

Modeling/Characterization

Electric energy storage

Hybrid electric drive

Power generation (photovoltaic cell, fuel cell etc.)

Components

Power module

ApplicationsWork scope

Topology

Package/Heatsink

ControlGate drive

Approach and Work ScopeApproach and Work Scope

UpUp--toto--date Accomplishments in Phase IIdate Accomplishments in Phase II

DCDC--AC inverter design.AC inverter design.

Power module design/prototype.Power module design/prototype.

Packaging/Thermal management. Packaging/Thermal management.

Gate design/prototype.Gate design/prototype.

Modeling/characterization.Modeling/characterization.

Preliminary inverter prototype/testing.Preliminary inverter prototype/testing.

Preliminary commercialization.Preliminary commercialization.

Results Results –– Inverter DesignInverter Design

ThreeThree--phase inverterphase inverter

Controll Board 1

SIC JFET MODULE

C3

Four ChannelAUXILIARY GATE DRIVE POWER

CONTROL POWER

V,I,T Measure

AUTO RESET CIRCUIT

PWMSignals

Temperature

F2407A

EMI

C1 C2

Heatsink

A

B

C

PC

LPT1

MAIN POWER BOARD

VTia ib

Faults Generate and DisplayPOS/NEG VOLT TOTEM DRIVE

OPTICAL ISOLATION

PWM PROTECT LOGIC

EzDSP

LOAD

DRIVER & PROTECT BOARD

K1

Controll Board 2 PWM

SignalsdSPACEDS1104

S1

S2

S3

S4

S5

S6

D1

D2

D3

D4

D5

D6

Soft Start

POWER SUPPLYAn inverter is interfaced with:

1) A large battery bank for energy storage.

2) An AC system.

Power Module Design and PrototypePower Module Design and Prototype

•• SiC power modules using commercial SiC power modules using commercial SiC devicesSiC devices– SiC diodes and SiC JFETs

•• Device/module parallelingDevice/module paralleling– Low current rating (e.g. 15-30 A), 2-4 ps.

devices parallel into an array (for a single gate drive) to form a unit power module

– High current rating (e.g. 80-100 A), 4-6 ps. unit power modules parallel into an array of power modules

Design 1- Six packed, 3 phase Design 2- Six packed, 3 phase

Power module integrated with gate drive

Packaging and Thermal ManagementPackaging and Thermal Management

• Thermal packaging– AlN package substrate for high temperature packaging

– Networking microchannel cooling and graphite foam heatsink• Metallization for interconnect, die attachment and joining

– Active metallization on AlN (vs. commercial CB AlN)• Die attachment of SiC devices

– Au-Sn (280 C)• Joining – Packaging and heatsink

– Active brazing and metallization/soldering• Wire bonding

– Al or Au wires

Gate DriveGate Drive

• Challenging issues/approach – Normally-on device of JFET for high frequency operation – Commercially available Si devices --> a Drive & Protect Circuit Board

NC

A

KNC

VCC

Vo

VEE

Vo

HCPL3120U25

510R76

104

C43

104

C45

104C44

35V/100uF

C46

35V/100uF

C47

C2

B1 E3

MJD44H11Q7

C2

B1

E3

MJD45H11

Q8

10R77

15K

R78

VCC1

VSS1

PWMA+GA+

SA+

1N4749D21

VCC1

VSS1

SA+

4148D19

10K

R79

LEDD20

3K

R80

101C88

104C107

104

C108

5VD37

24VD38

CONVERTER

DC P

DC N

FLYBACKDC/DC

A drive & protect circuit boardA gate drive circuit design

Modeling and SimulationModeling and Simulation

• Model power module/inverter performance (circuit/thermal modeling).

• Analyze system-level impacts of using SiC power devices compared with using Si power devices.

C40.1u

V11100Vdc

U41A

LM393

+3

-2

V+

8V

-4

OUT1

C50.1u

U74A

LM339

+5

-4

V+

3V

-12

OUT2

V9

15Vdc

V10

12Vdc

V112Vdc

R61k

R710k

R19

1k

V65Vdc

V72Vdc

QbreakN

Q1

QbreakP

Q2

V16

15Vdc

V17

12Vdc

V1815Vdc

R21

10

V1912Vdc

R131k

C110p

C81p

R8

300

R10

300U43A

CD4081B

1

23

U44A

CD4081B

1

23

Vcc

U36

HCPL2602

R141k

R1510k

R16

10

R1710k

0

J1

SiC JFET

J2

SiC JFET

U37A

LM339

+5

-4

V+

3V

-12

OUT2

V45Vdc

V52Vdc

V215Vdc

V312Vdc

R1110k

R510k

C21p

C31p

U18

3usDELAY

U19

3usDELAY

V8

TD = 0us

TF = 49.99usPW = 0.02usPER = 100us

V1 = 0

TR = 49.99us

V2 = 10

R2

1k

R3

1k

R45k

.model SiC JFET (Tox=0.2u Uo=1200 Phi=.6 Kp=1.038u W=8.05 L=2u Rs=20m Vto=1. 06Rd=.05 Rds=1M Cgso=30.8p Cgdo=10.7p Cbd=55.56p Mj=.8512Rg=0 Is=10f N=1 Rb=1m)

U40A

CD4081B

1

23

R9

1k

U62A

LM339

+5

-4

V+

3V

-12

OUT2

V142Vdc

QbreakP

Q3

QbreakN

Q4

R24

1k

R251000k

U67A

CD4011A

31

2

U68A

CD4011A

31

2

U69A

CD4011A

31

2

R2010k

U65A

CD4009A

3 2

U15A

LM339

+5

-4

V+

3V

-12

OUT2

C1010u

R1820

L13mH

1

2

V12100Vdc

V13Vdc

U38A

LM339

+5

-4

V+

3V

-12

OUT2

R1

1k

R121000

V13

FREQ = 50VAMPL = 4.5VOFF = 5

Vcc

U35

HCPL2602

V155Vdc

SiC JFET inverter simulation circuit

Inverter PrototypeInverter Prototype

• A 5 kVA DC-AC inverter prototype • Integrate power module, package, and gate drive

A prototype of a 5 kVA SiC inverter

Characterization Characterization

S1

S2

D1

D2

1000uFC1

1mHL1

1uFC2

30 OhmR1

VCC 300V DC

GND

-24V DC

SiC JFET

SiC

DIO

DE

SiC JFET

INVERTERM

PZ 4000 POWER ANALYZER

DC+

DC-

ia

ib

ic

Switching time measurement circuit

Inverter power measurement circuit DC power source

Motor drive

Commercialization Efforts

• Commercial Companies – BSST (a subsidiary of Amerigon), brazing/packaging

thermoelectrical (TE) modules for waste heat recovery in vehicles.

– Hamilton Sundstrand (a United Technologies Company), joining/high-efficiency heat exchanger for aerospace application.

– Ceradyne (a major ceramic company for armor, energy and engine applications), High-temperature bonding technology for oil-drilling ceramic parts.

• Government Contracts– NASA SBIR Projects on SiC inverters (Phase I and now II). – Navy SBIR Project on SiC inverter for motor control (Phase I).– Army SBIR Project on high-efficiency thermal management

(Phase I and Phase II pending).– DoE SBIR Project on an Innovative bonding method for high

temperature, high power density SiC devices

Ongoing WorkOngoing Work

• Converter fabrication, characterization and demonstration –– Fabricate, test and characterize inverterFabricate, test and characterize inverter

• A power module array (1200V, 120 A) by paralleling module units of 1200 V, 20 A• Gate drive (Honeywell SOI-based high temperature drive)• High- temperature thermal packaging

–– Analyze systemAnalyze system--level impacts of the SiC inverter with similar Si level impacts of the SiC inverter with similar Si invertersinverters

• Advantages of operations at high temperatures (smaller heatsink), power densities and frequencies (smaller passive component)

• Technical/economical benefits in terms of performance and cost

• Application and commercialization – Electric storage system (battery, capacitors)– Transportation (traction drive, hybrid electric vehicles)– Distributed power systems (Fuel cells, micro turbine, nuclear energy, and renewable

sources)– Potential products: SiC power modules and converters

Through this project, a highThrough this project, a high--efficiency compact affordable SiC inverter can be anticipated.efficiency compact affordable SiC inverter can be anticipated.

Appendix Appendix –– Benefits of Using SiC devicesBenefits of Using SiC devices

Provided by SICED, Germany

Si inverter SiC inverter

Energy efficiency ~ 95% 98-99%

Size/weight SiC inverters with 25-50% size/weight of Si ones depending on power levels.

Predicted by Modeling