driver circuit for IGBT

Thread Starter

Mohamad Knight

Joined Mar 21, 2016
23
HI EVERONE
could you help me?
I want to design circuit FOR driving Gate_IGBT (GT60N321)
to control the speed of dc motor (180 volt _ 2 HP)
I want to control the Igbt-Gate by pic microcontroller (pwm_pin)
and this is the circuit but it isnot work
isolated to-tempole2.jpg
 

Janis59

Joined Aug 21, 2017
1,143
Datasheet: input capacitance 4 nF, rise / fall times 230 / 700 nsec, gate charge ca 200 nCoulomb. Thus Q=i*t or 200e-9=i*230e-9 or i=(~) 1 Ampere. I wonder if 2n2222 is able for so large current. The complementary pair ought be used some more powerful.
 

ian field

Joined Oct 27, 2012
6,539
HI EVERONE
could you help me?
I want to design circuit FOR driving Gate_IGBT (GT60N321)
to control the speed of dc motor (180 volt _ 2 HP)
I want to control the Igbt-Gate by pic microcontroller (pwm_pin)
and this is the circuit but it isnot work
View attachment 146124
The IGBT is basically a MOSFET with an emitter follower bipolar transistor hanging from the drain. Driving it is just the same as a MOSFET, but the emitter follower makes it a slow switching device.

IGBTs were initially developed because early MOSFETs had high RDSon and conduction losses - modern MOSFETs have much better RDSon and the advantages of IGBTs are beginning to lose relevance.

When I serviced monitors for a living - I found a lot of blown IGBTs in PSUs - there is a general trend for higher switching frequency to get away with smaller cheaper magnetics, some designers didn't understand IGBTs aren't fast enough to do it.
 

Thread Starter

Mohamad Knight

Joined Mar 21, 2016
23
I have
Datasheet: input capacitance 4 nF, rise / fall times 230 / 700 nsec, gate charge ca 200 nCoulomb. Thus Q=i*t or 200e-9=i*230e-9 or i=(~) 1 Ampere. I wonder if 2n2222 is able for so large current. The complementary pair ought be used some more powerful.
Thank you my friends
but ultimeately I' d like to know the intact circuit

is it wrong or right?
The motor should be in the transistor collector side, not in the emitter.
 

IamJatinah

Joined Oct 22, 2014
122
Hi All,... There are differences in biasing and switching IGBT devices vs FET-based. The original circuit shown had a few thoughts for me. There is a ground on the bottom of the motor and a wire going to circuit ground from the top side of the motor if I saw that right. Tuned snubber circuits may be considered around the main switch depending on switching frequency, and the circuit looks a lot like a certain board I know that is a motor controller using the 16f877 PIC chip.... for the same size motors as well... good luck
 

Thread Starter

Mohamad Knight

Joined Mar 21, 2016
23
Hi all
I HAVE put snubber circuit for IGBT (C1-R9) C1(100nf-400volt) - R9(25ohm-5watt)
What are the correct values c1- R9 ?
and i have put R8 (100k) as a volt divider to get about 13 volt on the collecter of Q2
and this is the final electrical diagram
 

Attachments

IamJatinah

Joined Oct 22, 2014
122
Snubbers vary on frequency and currents being switched, which are substantial. I might up the snubber resistor a bit to say 220ohm 3 or 5W, or maybe not needed?. The kickback diode is large and fast enough for the motor current during the IGBT off-cycle? For this +Vbulk maybe something like 30A 600Prv Ultra-fast ?
FFPF30U60STU by Fairchild
 

Thread Starter

Mohamad Knight

Joined Mar 21, 2016
23
hello
I have noticed some things
the value of Main power supply is 265 volt and the motor is 180 volt - 2HP
I have chenged R3 TO 10K OHM
the ground in BAT1(12 VOLT) is the same ground in Main power supply (265VDC)?
I have tried this circuit , but I noticed that node (A) heated up a lot and it give a little somke
I need to know what is the wrong and why did this happen to my circuit ?
and how could i solve this problem
and there is a lot of noise
PLEASE help me
 

Attachments

IamJatinah

Joined Oct 22, 2014
122
I have tied resistance(1 ohm - 10 watt) in series with motor to divided The voltage (the main power supply)(265 v dc)
Well...it's a bit of an incomplete design as it sits... do you have measurement scopes?
What frequency ? You didn't mention it was 220vAC input, a 1-ohm resistor will blow apart, and did you program the 16f877 yourself? If so, what are the Min/Max Duty, dead-times, timing reference? We might like the entire drawing to make any further considerations as we don't have any idea of storage capacitors, current issues like inrush - Isense and limits, no idea of cold-side Vcc, there is no current monitoring for that motor current shown? Dumping series-resistance on a motor rail is undesired. Double rated voltage on a motor is also edging on dangerous? Designing should include safeguards and limiting but this circuit could let loose in a pretty nasty way. ?
 

Thread Starter

Mohamad Knight

Joined Mar 21, 2016
23
I uesed very big heat sinks for IGBT (GT60N321)
and I uesed MUR6060PT as a free-wheeling diode In parallel the dc motor
the circuit worked well , but when I Turned off the circuit
the IGBT (GT60N321) damaged
could you help me why the IGBT damage?
 

Attachments

ebp

Joined Feb 8, 2018
2,332
There may be some other cause, but it is likely that bad gate drive voltage is the cause of failure. If the supply voltage for the driver is too low, as will happen at turn-on and turn-off, it can cause the IGBT to operate in the "linear" region where it is only partially turned on. This can lead to extremely high power dissipation that can destroy the device.

Integrated circuit drivers prevent this problem with undervoltage detection circuitry.
 
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