Power
Converter
Course,
Warrington
High Power Active
Devices
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here
12.05.2005
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here
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here
© ABB Switzerland Ltd - 1 5/27/2004
Eric Carroll, ABB Switzerland
© ABB Switzerland Ltd - 2 -
INTRODUCTION
Electronic Switches
„
Thyristor
Can be turned on by gate signal but can only be turned off by
reversal of the anode current
„
Gate Turn-Off Thyristor (GTO)
Can be turned on and off by the gate signal but requires large
capacitor (snubber) across device to limit dv/dt
„
Transistor (transitional resistor)
© ABB Switzerland Ltd - 3 -
Can be turned on and off by the gate (or base) signal but has high
conduction losses (its an amplifier, not a switch)
„
Integrated Gate Commutated Thyristor (IGCT)
Can be turned on and off by the gate signal, has low conduction
loss and requires no dv/dt snubber
Available Self-Commutated Semiconductor Devices
THYRISTORS
TRANSISTORS
Anode
Anode
Collector
GTO (Gate Turn-Off Thyristor)
BIPOLAR TRANSISTOR
P
P
MCT (MOS-Controlled Thyristor)
N
P
Gate
Gate
N
Base
P
P
FCTh (Field-Controlled Thyristor)
N
DARLINGTON TRANSISTOR
P
N
MOSFET
N
P
N
FCT (Field Controlled Transistor)
SITh (Static Induction Thyristor)
Emitter
MTO (MOS Turn-Off Thyristor)
Cathode
Cathode
EST (Emitter-Switched Thyristor)
Anode
© ABB Switzerland Ltd - 4 -
IGTT (Insulated Gate Turn-off Thyristor)
SIT (Static Induction Transistor)
IEGT (Injection EnhancedCollector
(insulated) Gate Transistor)
IGBT (Insulated Gate
Bipolar Transistor)
Base
Gate
IGT (Insulated Gate
Thyristor)
IGCT (Integrated Gate-Commutated
Cathode
Thyristor)
Emitter
High Power Turn-off Devices
Power Semiconductors
Turn-off Devices
Thyristors
ƒ Line commutated
© ABB Switzerland Ltd - 5 -
Transistors
ƒ Darlingtons
ƒ IGBTs
Thyristors
ƒ GTOs
ƒ IGCTs
ƒ Fast
ƒ Bi-directional
ƒ Pulse
Diodes
ƒ Fast
ƒ Line commutated
ƒ Avalanche
Power Semiconductors …
are switches….
© ABB Switzerland Ltd - 6 -
VDC
VAC
….for converting electrical energy
Turn-on Switches (Thyristors)
Thyristors (PCTs)
V
thyristors produce voltage distortion
in phase control mode
„
„
t
will ultimately be replaced by ToDs, except...
© ABB Switzerland Ltd - 7 -
in AC configuration for:
„
transfer switches
„
tap changers
„
line interrupters
V
t
1000
100
30
10
total energy
6
electrification
2
1
37%
% electrification
15%
0
2030
2020
2010
2000
Source :
Mitsubishi Electric
1990
1970
1960
1950
1980
6%
3%
0.1
© ABB Switzerland Ltd - 8 -
397
147
200
100
57
1940
Millions of Barrels/Day
World Energy Consumption …
... drives the need for high power electronics
Energy trend
By 2020:
• Energy consumption will double
• Electricity generation will double
• Electrification of end-consumption will quintuple
Today, only 15% of electricity flows via electronics
© ABB Switzerland Ltd - 9 -
Medium Voltage conversion has only been economically possible in
the last 10 years
Power conversion at MV levels set to grow faster than LV (20% p.a.)
© ABB Switzerland Ltd - 10 -
SELF- COMMUTATED
INVERTERS
Basic Topologies
R
L
S1
S3
S5
S2
S4
S6
DclampLs
IGCT Inverter
VR
Cclamp
Clamp
circuit
© ABB Switzerland Ltd - 11 -
FWD1
S1
S3
FWD6
S5
VDC
IGBT Inverter
S2
S4
S6
Turn-on waveforms for IGCTs and IGBTs
Eon − circuit = (t 2 − t 0) •Vdc • ( Iload + Irr) 2 .... (1)
Vswitch or L = VDC
Iswitch
Iload
Ipk
di/dt|on
IFWD
Vswitch =
f(t)
ton
© ABB Switzerland Ltd - 12 -
t0
t3
t1
t2
Irr
t3
E on − device ≈ I load • ∫ V switch ( t ). dt ............. ( 2 )
t2
© ABB Switzerland Ltd - 13 -
DEVICES
© ABB Switzerland Ltd - 14 -
IGBTs
© ABB Switzerland Ltd - 15 -
IGBTs – key features
„
Transistors with insulated gate
„
Allow dv/dt and di/dt control via gate signal
(losses)
„
High on-state voltage
(transistor)
„
High turn-on losses (no snubber)
„
Low gate power requirements
(voltage control)
„
No passives required
(independant dv/dt and di/dt control)
© ABB Switzerland Ltd - 16 -
HiPak™ High Power IGBT Modules
Voltage
Current
Type
Part Number
2500V
3300V
3300V
6500V
1200A
1200A
1200A
600A
Single
Single
Single
Single
5SNA 1200E250100
5SNA 1200E330100
5SNA 1200G330100*
5SNA 0600G650100*
Vce
125°C
3.1V
3.8V
3.8V
4.7V
VF
125°C
1.8V
2.35V
2.35V
4.0V
* High voltage version
AlSiC base-plate & AlN substrate
Eoff
125°C
1.25J
1.95J
1.95J
3.5J
Eon
125°C
1.15J
1.89J
1.89J
4.0J
Vdc
1250V
1800V
1800V
3600V
StakPak™ - stackable press-packs (collector side)
StakPak-H4: 2.5 kV/1300 to 3000 A
StakPak-L2: 4.5 kV/600 to 1000 A
© ABB Switzerland Ltd - 17 -
StakPak-J6: 4.5 kV/2000 to 3000 A
StakPak-H6: 2.5 kV/ 2000A to 3000 A
IGBT Press-packs
inert gas
molybdenum
ceramic
copper
Conventional IGBT presspack:
requires tight mechanical
tolerances
silicon
chip
close-up
copper
module lid
(copper)
sub-module frame
(polymeric)
© ABB Switzerland Ltd - 18 -
current bypass
module outer frame
(fibreglass reinforced polymer)
StakPak™ IGBT presspack with individual
springs:
suitable for long stacks
with compounded
tolerances
spring washer pack
∆x
silicon chip
base-plate
silicon gel
StakPak™ HVDC Valve
© ABB Switzerland Ltd - 19 -
Long stacks would require very
tight mechanical tolerances to
ensure identical force on each
chip in each housing:
„
on assembly
„
over time
„
with temperature cycling
„
with shock and vibration
© ABB Switzerland Ltd - 20 -
IGBT Trends
© ABB Switzerland Ltd - 21 -
IGBT Trends
„
Higher voltages
„
Higher Safe Operating Area (SOA)
„
Softer (controlled) switching
Soft switching: 3.3kV SPT* IGBT/Diode chip-set
110
2200
Vce
90
1800
80
1600
70
1400
60
IGBT Turn-off
Vcc= 1800V
Ic= 50A
RGoff= 33ohm
Ls= 2.4µH
Tj= 125°C
1200
Ic
50
1000
40
800
30
20
600
Vge
400
10
200
0
0
-10
-200
-20
-400
Time [250 nsec/div]
150
125
2200
IF
100
VR
2000
75
1800
50
1600
25
1400
0
1200
-25
1000
-50
800
-75
600
-100
400
-125
200
IF (A)
Diode Turn-off
VR= 1800V
IF= 100A
RGon= 33ohm
Ls= 2.4µH
Tj= 125°C
2400
-150
* Soft Punch Through
Time [250 nsec/div]
0
VR (V)
© ABB Switzerland Ltd - 22 -
2000
Vce (V)
Ic (A), Vge (V)
100
90
5000
80
4500
70
4000
3500
60
3000
50
2500
40
30
high di/dt giving
rise to EMI issues
20
conventional
PT device
2000
SPT
1000
1500
© ABB Switzerland Ltd - 23 -
10
500
0
0.0
1.0
2.0
3.0
4.0
5.0
6.0
time [microseconds]
7.0
8.0
9.0
0
10.0
voltage [V]
current [A]
Soft switching: 8 kV IGBT PT vs SPT
3.3kV Diode RBSOA Performance
3.3kV/100A Diode RBSOA during Reverse Recovery
VR= 2500V, IF= 200A, di/dt=1000A/µs, Ls= 2.4µH, Tj= 125°C
250
200
5500
IF = 2 x Inom inal
5000
150
100
4500
Inom inal
4000
50
3500
IF (A)
3000
-50
2500
VR
-100
-150
1500
Dynam ic
Avalanche
© ABB Switzerland Ltd - 24 -
-200
-250
-300
2000
1000
500
Tim e [250 nsec/div]
Peak Power = 0.8 MW/cm2
No clamp, no snubber
0
VR (V)
SSCM
0
4.5kV IGBT RBSOA Performance
4.5kV/40A IGBT RBSOA during Turn-off
Vcc= 3600V, Ic= 120A, RG= 0ohm, Ls= 12µH, Tj= 125°C
220
5500
180
4500
160
4000
140
Vce
Ic = 3 x Inominal
3500
120
3000
100
2500
80
Dynamic
Avalanche
60
40
© ABB Switzerland Ltd - 25 -
5000
SSCM
Inominal
1500
1000
20
0
2000
500
Vge
-20
0
-500
Time [250 nsec/div]
Peak Power = 0.5 MW/cm2
No Clamp, No Snubbers
Vce (V)
Ic (A), Vge (V)
200
6.5kV IGBT RBSOA Performance
© ABB Switzerland Ltd - 26 -
140
130
120
110
100
90
80
70
60
50
40
30
20
10
0
-1 0
-2 0
SSCM
Ic = 2 x In o m in a l
V ce
D yn a m ic
A v a la n c h e
In o m in a l
Vge
T im e [2 5 0 n s e c /d iv ]
Peak Power = 0.25 MW/cm2
No Clamp, No Snubbers
7000
6500
6000
5500
5000
4500
4000
3500
3000
2500
2000
1500
1000
500
0
-5 0 0
-1 0 0 0
Vce (V)
Ic (A), Vge (V)
6.5kV/2x25A IGBT RBSOA during Turn-off
Vcc= 4500V, Ic= 100A, RG= 0ohm, Ls= 20µH, Tj= 125°C
6.5kV IGBT Short Circuit Performance
6.5kV/25A IGBT SCSOA during Short Circuit
Vcc= 4500V, Icpeak= 290A, VGE= 18V, Ls= 2.4µH, Tj= 25°C
300
275
6000
Ic > 10 x Inominal
© ABB Switzerland Ltd - 27 -
Vce
5000
225
4500
200
4000
175
3500
150
3000
125
2500
100
2000
75
1500
50
1000
25
500
0
Time [2 usec/div]
Peak Power = 1.35 MW/cm2
No Clamp, No Snubbers
0
Vce (V)
Ic (A)
250
5500
3.3kV IGBT Module RBSOA Performance
© ABB Switzerland Ltd - 28 -
3.3kV/1200A IGBT module during Turn-off (24 IGBTs)
Vcc= 2600V, Ic= 5000A, RG= 1.5ohm, Ls= 280nH, Tj= 125°C
No clamp, no snubbers
© ABB Switzerland Ltd - 29 -
IGCTs
© ABB Switzerland Ltd - 30 -
IGCTs – key features
„
Thyristor with integrated gate unit
„
Low on-state voltage
(thyristor)
„
Negligible turn-on losses
(turn-on snubber)
„
No explosive failures
(fault current limitation by circuit)
Principle of IGCT Operation
Anode
Anode
P
VAK
N
N
I AK
P
Gate
P
Gate
N
P
N
I GK
© ABB Switzerland Ltd - 31 -
Cathode
Conducting Thyristor
- VGK
Cathode
Blocking Transistor
IGCT turn-off
Vd (kV)
Ia (kA)
Vdm
anode voltage Vd
4
Itgq
3
3
2
1
4
thyristor
x
anode current
Ia
transistor
Tj = 90°C
1
0
0
starts to block
-10
© ABB Switzerland Ltd - 32 -
gate voltage Vg
-20
Vg (V)
2
15
20
25
30
35
t (µ s)
General turn-on waveforms for IGCTs and IGBTs
Eon-circuit
Vswitch or L = VDC
Iswitch
Iload
IFWD
Ipk
© ABB Switzerland Ltd - 33 -
di/dton
Vswitch = f(t)
ton
t0
Eon-device
t1
t2
IRR
t3
1500 A IGBT turning on 1000 A from 3000 V
IC [250 A/div]
833 A/µs
EON = 7.4 WS
© ABB Switzerland Ltd - 34 -
EON circuit
EON device
VCE [500 V/div]
time [ 2 µs/div]
EON-circuit = 4.1 Ws
4000 A IGCT turning on 1000 A from 3000 V
0.7
EON-device
VAK, IA, [V, A]
3000
2500
0.5
2000
0.4
1500
0.3
1000
0.2
500
0
0.E+00
© ABB Switzerland Ltd - 35 -
0.6
0.1
1340 A/µs
5.E-06
1.E-05
2.E-05
2.E-05
t [s]
Eon − circuit = (t 2 − t 0) • Vdc • ( Iload + Irr ) 2 .... (1)
=1.5 µs • 3000V • 1900 A /2 = 4.3 Ws
0
3.E-05
Eon [Ws]
3500
Adjustment of dv/dt by lifetime control
VAK
IA, VAK, [A, V]
4000
3000
medium lifetime
low lifetime
high lifetime
2000
IA
1000
© ABB Switzerland Ltd - 36 -
0
6
8
10
t [µ s]
12
14
© ABB Switzerland Ltd - 37 -
Low inductance housing
4 kA/4.5 kV IGCTs
power supply
connection
visible LED
indicators
IGCT
zzzz
all copper housing
Status Feedback
Command Signal
© ABB Switzerland Ltd - 38 -
optical fibre connectors
GCT
© ABB Switzerland Ltd - 39 -
30 MW IGCT Power Management
15 + 15 MW 3-Level Back-to-Back Converter
for three-phase to single-phase conversion Converter efficiency = 99.2%
4 kA/4.5 kV IGCT at 25 kHz in burst mode
Anode voltage and current (V, A)
5000
4500
4000
v
I
3500
3000
2500
2000
1500
1000
© ABB Switzerland Ltd - 40 -
500
0
0.E+00
2.E-04
4.E-04
6.E-04
8.E-04
1.E-03
time (s)
VDC start = 3.5 kV
VDM peak = 4.5 kV
TJ start = 25 °C
α = 0.5
ITGQ peak = 4 kA
© ABB Switzerland Ltd - 41 -
IGCT Outlook
© ABB Switzerland Ltd - 42 -
IGDT
Structure of IGDT – Integrated Gate Dual Transistor
K
G1
K
G1
K
G1
G1
N
P
N
P
G2
A
G2
G2
© ABB Switzerland Ltd - 43 -
A
Dual Gate Turn-off Thyristor
A
G2
91 mm 4.5 kV IGDT turn-off
© ABB Switzerland Ltd - 44 -
no tail current
Dual-gate IGCT @ 85°C - gates triggered simultaneously
VDC = 2.8 kV
ITGQ = 3.3 kA
VDRM = 4.5 kV
VTM = 2.1 V @ 4 kA/125°C
IGDT Series connection: leakage current reduction
140
120
anode gate floating
(no bias)
ID (mA)
100
80
60
(V DC = 2800 V)
anode gate with 20V
reverse biased
40
© ABB Switzerland Ltd - 45 -
20
0
75
100
125
150
T J (°C)
140°C
175
91 mm 4.5 kV IGDT - Leakage current control
© ABB Switzerland Ltd - 46 -
ID - anode leakage current [mA]
VGK= -20V, TJ = 25°C
35
30
25
20
500V
1000V
1500V
2000V
2400V
15
10
5
0
0
5
10
15
IGA Anode gate current [mA]
20
25
IGDT anode gate control of tail current
IDUT2
V1
VG1
© ABB Switzerland Ltd - 47 -
V1
VG1
VG2
kV kA
kA
V
IDUT2
VG2
kV
1.0
2.5
1.0
2.5
0.8
2.0
0.8
2.0
0.6
1.5
0.6
1.5
0.4
1.0
0.4
1.0
0.2
0.5
0.2
0.5
0.0
0.0
0.0
0.0
2.4
V
2.4
2.2
2.2
2.0
2.0
1.8
1.8
1.6
1.6
1.4
1.4
300
320
340
300
µs
320
340
µs
© ABB Switzerland Ltd - 48 -
Increased SOA
IGCT SOA improvement at 4.5 kV
© ABB Switzerland Ltd - 49 -
TODAY
38 mm reverse conducting
TOMORROW
250 kW/cm2
1000 kW/cm2
250 kW/cm2
400 kW/cm2
91 mm asymmetric
6.5 kA @ 2.8 kVDC on 91 mm wafer
IT
7000
5
Snubberless turn-off
Tj = 125°C, VD = 2.8kV
© ABB Switzerland Ltd - 50 -
5000
0
-5
4000
-10
VAK
3000
-15
2000
1000
-20
0
-25
1
3
5
7
9
t [µ s]
Developmental 4” 4.5 kV IGCT with improved GU and silicon
design allowing 50% SOA improvement
VGK [V]
VAK, IT [V. A]
6000
© ABB Switzerland Ltd - 51 -
4.5
1.8
4
1.6
VAK
Ioff
3.5
1.4
3
1.2
P
2.5
1
2
0.8
TJ = 115°C
1.5
0.6
1
0.4
0.5
0.2
0
0
-3
-2
-1
0
1
2
3
4
5
6
t [µ s]
Developmental 2” 4.5 kV RC_IGCT with improved GU and
silicon design allowing 300% SOA improvement
7
Ioff [kA]
VAK [kV], P [MW]
1.3 kA @ 2.8 kVDC on 38 mm RC wafer
© ABB Switzerland Ltd - 52 -
10 kV IGCT
© ABB Switzerland Ltd - 53 -
Engineering Sample of 68 mm 10 kV IGCT
Forward Blocking Characteristics at 25°C
© ABB Switzerland Ltd - 54 -
magnified by factor 1000:
1 µA / div
(<17 µA @ 10 kV, 25°C)
Forward Blocking Characteristics at 125°C
© ABB Switzerland Ltd - 55 -
(<14 mA @ 7 kV, 125°C)
(8-13 mA @ 6 kV, 125°C, PL=50W-80W ( 5%-10% of PRP)
Turn-off Waveforms (SOA)
© ABB Switzerland Ltd - 56 -
Operating conditions:
VDC= 7kV, IA = 1000A, Tj = 85°C
Switching characteristics:
Eoff = 14.8 J, VAK,max = 8 kV, toff = 8µs, tf = 1µs, ttail = 5µs, 250 kW/cm2
© ABB Switzerland Ltd - 57 -
Conclusions
SOA Limits of HV Devices are increasing
I
Pushing the RBSOA Limits
nxI
2xI
Device Capability
nom
New Limits
nom
State-Of-The-Art Limits
V
© ABB Switzerland Ltd - 58 -
Vrated
„
VSSCM
Under RBSOA operational conditions
„
Devices withstands dynamic avalanche mode
„
IGBTs withstands “SSCM” mode
„
Devices achieve the ultimate square SOA behaviour
Switching-Self-Clamping-Mode “SSCM”
dv/dt
Dynamic
Avalanche
Self
Clamping
VDC
IC
© ABB Switzerland Ltd - 59 -
di
„
VSSCM − VDC
=
dt
LS
IGBT SOA turn-off waveforms including SSCM
„
devices start to limit voltage during turn-off
„ over-voltage safely reaches the static breakdown after turn-off
© ABB Switzerland Ltd - 60 -
„
For high power conversion, only two devices possible
today:
„
IGBT
„
IGCT
„
Safe Operating Area is increasing from 250 kW/cm2
to 1 MW/cm2
„
IGDT offers possibility of high voltage devices with low
losses (future?)
© ABB Switzerland Ltd - 61 -
Challenges
Challenges for HV Power ToDs
© ABB Switzerland Ltd - 62 -
„
High voltage devices present following challenges:
„
Dynamic Avalanche ruggedness (for reliable operation)
„
Short Circuit Failure Modes (IGBT) and fault interruption (IGCT)
„
Design Trade-off between Losses and SOA
„
Critical Punch-Through voltages (for controllable voltage, low EMI)
„
High DC link voltage (leakage stability, cosmic ray withstand)
„
Large inductance and overshoot voltages in HV power systems
„
High frequency (limited by losses, TJ)
Challenges for this decade
„
10 kV switches with 1 kHz snubberless operation
(for the 6.9 kVRMS MV line for drives and power conditioners)
„
Snubberless series operation
(static and dynamic for MV lines > 6.9 kVRMS)
„
Power supply free operation
(autogenous power supply for series connection)
© ABB Switzerland Ltd - 63 -
„
System cost-reduction
(e.g. pay-back times ≈ 1 year for MV Drives)
„
Reduced thermal resistance and increased TJ
„ Reduced
losses?