An Optically Isolated HV-IGBT Based
Mega-Watt Cascade Inverter Building
Block for DER Applications
U.S. Department of Energy SBIR Grant
DE-FG02-01ER83142
August 27, 2001  February 26, 2001
Airak, Inc.
Paul Grems Duncan
9058 Euclid Avenue
Manassas, Virginia 20110-5308
voice: [phone]
fax: [phone]
[e-mail]
Project Goals
Primary: Develop a new full-bridge, three phase,
megawatt inverter topology based upon HV-
IGBTs with optical current, voltage, and
temperature sensing in addition to
command/control interfacing.
Secondary: Compare/contrast advantages of
optical sensor and control methodologies over
conventional methodologies (e.g. safety,
reliability, costs, response, efficiency, phase
margin, dynamic range, etc.).
Team Members
Administrative
Management
Technical
&
Management
Funding
- Stan Atcitty
- Dr. Imre Gyuk
Optical Sensor
and System
Design
- Paul Duncan
Power
Electronics
Subsystem
Design
- Dr. Jason Lai
Motivation
Optical Sensor Technologies + High Power
Systems => Tremendous Advantages
Commercial Point of View:  Dual Use for
both Power Electronics and Utility Power
Industries (i.e. Potential Markets are Large)
System Configuration
is
iL
Load
ider
DER
vas Cascaded inverter
vbs vcs
Transformer
sources
Lfa
S1a S3a
Vd1
va
vS vC S2a
S4a
Lfb
S1b
S3b
Vd2
vb
S2b
S4b
Lfc
S3c
S1ca
Vd3
vc
S2c S4c
Sensor & Control Configuration
Complete Module for Cascaded Inverter
Fiber Optic
HV-IGBTs
Sensors
DER S1a S3a
Source
S2a
S4a
Gate Drivers
Optical
idc
vdc
iac vac
fiber links
Interface Sensor
DSP
Circuit Conditioning
Circuit
Why HV-IGBTs?
Compared to GTO or other thyristor-based
devices&
 Eliminate Current Snubbers and Voltage
Clamps
 Simplify Gate Drive Circuitry and Isolation
 Provide Cost Advantage at System Level
 Increased Efficiency and Reliability
Implementation
IGBT Module Test Setup
C1
G1
Lo Inductive
Load
2mH
High freq.
C2 E1
Vdc Cdc
cap. 4.7uF
0 ~ 650V
2mF
DUT
G2
Busbar
E2 To Scope
1A:0.01V
Bushing
10:1
Pulse
 small
Homemade
Generator
copper
CT with
tube
Pearson 411 CT
small toroid
1A:0.1V
ferrite core
µ=2600
HV-IGBT Turn-on and Turn-off Waveforms
Voltage, Current and Switching Energy at 360 kW
Current overshoot
Voltage overshoot
due to diode reverse
due to Llk(di/dt)
recovery
VCE (200V/div)
IC (200A/div)
Eon = 120 mJ
VCE (200V/div) Eoff = 100 mJ
IC (200A/div)
120 mJ
100 mJ
Time (0.2us/div) Time (0.2us/div)
(b) Turn off
(a) Turn on
IGBT Test Structure
Liquid Cooled
Heat Sink
IGBT
Pulse Tester
Bode Plots of the Control Loop
Transfer Function
Ki/VPWMHi(s) Gid(s)
0 dB line
65°
P.M.
8 kHz control bandwidth
Little phase shift at 60 Hz
Simulated Voltage and Current
Waveforms
Vdc
vab
van
ia
0
0s 10ms 20ms 30ms 40ms 50ms
Time
Frequency Spectra of
Phase A Current
Har. Freq Ia Ia "Ia
#(Hz) (A) (%) (°)
1 60 127.6 100% 1.0
5 300 0.07 0.05% -97.9
7 420 0.07 0.05% -99.7
11 660 0.08 0.05% -98.1
13 780 0.06 0.04% -124.6
17 1020 0.06 0.00% -104.2
19 1140 0.07 0.00% -106.2
1.0
0.8
THD = 0.14%
0.6
0.4
0.2
0.0
Frequency (Hz)
Phase A Current (pu)
Opto-Isolated Gate Driver Topology
+15V
6 1
8
7
+15V IGBT
FLT
Module
Ron
Optical Fiber 5
Roff
4
PWM -5V
2
3
-5V
+
+15V
12V
Optical Fiber Link Used
-
High Current Output Stage: >5A
Desaturation Protection
Low Component Count
-5V
MC33153
DC/DC
DC/DC
HV-IGBTs & Gate Drivers
During the 2nd Phase
of this program intend
to move toward
TM
Therma-Charge heat
pipe assemblies.
Therma-ChargeTM technology allows the rejection of
multiple kilowatts of heat from power semiconductors
directly to ambient air. This is an important conclusion
considering the potential alternative is a liquid pumped
loop system that has inherent long-term reliability
(leaks), maintenance (pump failure, fluid cleanliness,
filtering) and corresponding cost issues.
Why Optical Sensors?
Intrinsic Safety
Intrinsic Isolation
Increased Reliability
Higher Response
Greater Dynamic Range
Small Size and Weight
Fundamentals:
Sensing with Crystals
Photodetector #1
Applied
Magnetic or Voltage Field
E or H
Ć
Photodetector #2
Polarized
Laser Source
Polarization
Sensor
Beamsplitter
Material
Fundamentals:
Conversion to Current Measurements
The holy grail: I = total current flowing through a conductor
r
i = H " dl
+"
l
H=magnetic field intensity
r
r
B
H =
µ
(a constant)
B = magnetic flux density &
µ = permeability
µ
µ
µ
Ć
B =
(a constant)
Vl
Ć=polarization rotation
Ć
Ć
Ć
Sensor and Power Conditioning
Function
Code
Composer
FPGA
Studio
Foundation
Optical Sensors AED-106 A/D and
& PWM Interface
OptoElectronics PCB
TMS320C6701 EVM
&
IBM Compatible
AED-106 A/D
Rack Mount Chassis
To/From Gate Drivers
Optical Configuration (Voltage
or Current Sensor)
X
SMOF Fiber
1310 Laser FC Connector
Spool
Fusion
Coupler
Splices
SMOF
SMOF
FC-FC Inline
Adapter
FC-FC
X
FC Connectors (2)
Bulkhead FC
Sensor
1550 Laser Adapters (2) Connectors
(4)
Miniature
Polarizing
Beamsplitter
FC-FC Inline
Adapter
MMOF
SMOF Lo-Bi SMOF
Lo-Bi
ST Connectors (2)
Fiber Spool
p/o Front Panel
MMOF
PIN
Photodiodes
Optical Sensor Analog Conditioning
Anti-Aliasing Filter
1v pp maximum
TransZ TransZ Scaling
Buffer
Amplfier #1 Amplfier #2 Amplifier
C
DC Restoration
Analog Interface Connector to
Amplfier
AED-106 Samtec FTSH-125-01-L-
MT (to/from AED-106-J14)
(Optional)
AED-106 input channel
contains a series resistor of
Mitel
4.32kOhms. Set low-
Semiconductor
frequency pole IAW C=1/
MF432 ST
(27143*fp)
Photodiode
Optical Current Sensor Sectional
Fundamentals:
Bragg Grating Temperature Sensor
wideband fiber
fiber
optical Bragg
optic
source grating
coupler
///////
Spectrometer
refractive index variation
 - B
 - 
 - 
 - 
fiber




B



Bragg Temperature Sensor Data
Bragg Temperature Sensor
S/N: H0022014
739
738
y = 0.067x + 730.42
737
R2 = 0.9944
736
735
734
733
732
731
730
0 20 40 60 80 100 120
Temperature [deg C]
Wavelength [nm]
Pending Milestones
Power Electronics Subsystem Integration (Dec  01)
Optical Subsystem Integration (Dec  01)
Systems Integration (Jan  02)
Systems Testing/Comparative Analysis (Jan/Feb  02)
U.S. DoE Demonstration (Feb/Mar  02)
U.S. DoE Follow-on Proposal (Mar  02)
U.S. DoE 3-Phase System Development (Jun  02+)
Next Steps
Demonstration of MW-Level HV-IGBT and
Optical Technologies for Industry Partners
Joint Collaboration and Development of
Technologies for Specific Power
Electronics and Utility-Scale Applications
Q&A / Discussion
For Further Information Contact:
Paul Grems Duncan
9058 Euclid Avenue
Manassas, VA 20110-5308
Voice: 703-330-4961
[e-mail]