Transcript Power Devices Survey

Power Device Characteristics
Voltage Rating:
Off state blocking voltage – exceed and
destroy!
Current Rating:
On (saturation) state maximum –
exhibits current limiting, can result in damage if power/ junction
temperature rating is exceeded.
Switching speed:
Maximum rates of change of currents
and voltages – determines switching losses
On State Voltage: determines On-state losses.
Power rating:
Maximum internal power dissipation above
which junction temperature rises above damage level. Subject to
external cooling measures.
Solid State Power Devices
Bipolar Junction Transistors (BJT)
Insulated Gate Bipolar Transistor (IGBT)
Metal Oxide-Semiconductor Field Effect Transistor (MOSFET)
Thyristors (SCR, TRIAC)
Integrated-Gate-Controlled Thyristors (IGCT)
Gate Turn-Off Thyristors (GTO)
MOS Controlled Thyristors (MCT)
MOSFET –
High frequency ( > 100 khz)
“Low” Voltage ( < 300 v)
IGBT –
Very High Power (DC applications ~ Megawatts)
Low Frequency ( < 50 kHz)
Thyristors –
(Utility applications 1-2 Megawatts)
MOSFET
D
ID
ID
+
VDS
G
-
+
VGS S
VGS(th)
VGS
MOSFET Features
Voltage Rating : < 200 v Cannot tolerate reverse
voltages
Current Rating: Up to 200 A, can operate multiple
devices in Parallel
Low On-state Resistance when properly cooled
High switching speeds >100 kHz
Low energy drive requirements
IGBT
G
IC
C
IC
+
+
VCE
-
VGE -
VGE
E
VCE
IGBT Features
Voltage Rating : Up to 3 Kv Can tolerate
moderate reverse voltages
Current Rating: Up to 1200 A, can operate multiple
devices in Parallel
Low On-state Losses
Switching speeds up to 30 kHz
Low energy drive requirements
Integrated Power Modules (IPM)
Combine multiple power devices,
drive circuitry, fault protection and
heat sink into single module.
Single and multi phase motor drives.
Power Diodes
High Forward Currents – up to 5 kA
High Blocking (Reverse)Voltages – up to 9 kV
•
•
•
•
Line Frequency Diodes (60 Hz – 9 kV, 5 kA)
Fast Recovery Diodes (Rapid Turn-on)
Schottky Diodes (Low Forward/On voltage)
Silicon Carbide/SiC (High Voltage, High speed, High Temp)
IF
I F  I R (e
VBD
IR
VF
qVF
kT
 1)