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Intelligent Power Modules (IPM) Forum Discussions

Mahdimc1368
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Level 1

Hello

I designed the motor driver using the IC controller IMC102 and switch IFCM15P60GD for the motor PMSM with Power 750W, and in practical testing, at the time of connecting the AC input and in some cases during the operation Short ciruit between pin collector to emitter in IFCM15P60GD (Pin 22 , 23) and it fail , 

The diode that I put on the fiber in parallel with the body diode of the switch PFC is part number BYG20J ,Is my choice correct? Can it be the cause of damage to the PFC switch or may it be another reason?

PFC.JPG

board specifications

Input Voltage 165 - 265 Vrms  AC input
Input current 3 Arms input 220 VAC, IFCM15P60GD

Current per leg 2.1 Arms input 220VAC 

DC bus voltage 400 V

PFC switching frequency 50 kHz

Inverter switching frequency 15 kHz

PFC current sensing resistor 25 mΩ

Inverter current sensing resistor 50mΩ  (Single Shunt)

What solution do you suggest?

Best Regards.

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1 Solution
AZIZ_HASSAN
Moderator
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Moderator

Hi,

Thank you for posting at Infineon community.

Prima facie I could find a potential reason for the failure that the external diode selected by you is not rated as per the recommendations (the diode should have at least 2A,650V rating).But still I request you to answer the following questions to look for other possible reasons (if any).

AZIZ_HASSAN_0-1659688391253.png

 

Please answer following queries.

1) May I know whether the external diode also fails or just the internal IPM IGBT switch fails.

2) Since, you are sensing current at two places, may I know whether you encountered any overcurrent across these sense resistors when short circuit across PFC IGBT happens. If yes, can please share the waveform for overcurrent/short-circuit current.

3) If possible can you please share  waveforms across 22,23 pin along with input voltage, current and dc link voltage waveform when it happens so.

4) Does the current flows through the inverter module or this happens only during starting.

At the end, I  recommend you to retest the circuit with a suitable rated diode and let us know about it.

BR,

AZIZ HASSAN

View solution in original post

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7 Replies
AZIZ_HASSAN
Moderator
Moderator 100 sign-ins 50 solutions authored 10 likes received
Moderator

Hi,

Thank you for posting at Infineon community.

Prima facie I could find a potential reason for the failure that the external diode selected by you is not rated as per the recommendations (the diode should have at least 2A,650V rating).But still I request you to answer the following questions to look for other possible reasons (if any).

AZIZ_HASSAN_0-1659688391253.png

 

Please answer following queries.

1) May I know whether the external diode also fails or just the internal IPM IGBT switch fails.

2) Since, you are sensing current at two places, may I know whether you encountered any overcurrent across these sense resistors when short circuit across PFC IGBT happens. If yes, can please share the waveform for overcurrent/short-circuit current.

3) If possible can you please share  waveforms across 22,23 pin along with input voltage, current and dc link voltage waveform when it happens so.

4) Does the current flows through the inverter module or this happens only during starting.

At the end, I  recommend you to retest the circuit with a suitable rated diode and let us know about it.

BR,

AZIZ HASSAN

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Mahdimc1368
Level 1
5 replies posted 5 sign-ins 5 questions asked
Level 1

Hi  - Thanks for the reply.

According to your advice, I use diodes With part number BY399 - 800V-3A

Capture.JPG

When measuring the current of the self-boost is CCM (L= 1.7mH , VDC=390V, Rl=275, P=550W),   

 in practical testing With Motor  rated power 550 W, the network input parameters are THD current about 11%,

but I want to reduce it below 5%.

Is the cause of the increase THD due to working PFC in the state DCM?

How can I reduce THD?

Do I need to make changes in the controller or change the inductor value or do you suggest another solution?

What parameters should I change in MCEWizard (IMC102 ) for controller PFC?
How do I tune the parameters PFC in MCEWizard & MCEDesigner?

Thank you

 

 

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AZIZ_HASSAN
Moderator
Moderator 100 sign-ins 50 solutions authored 10 likes received
Moderator

Hi,

Sorry for the late reply.

It would be helpful if you tell us  whether your short circuit problem solved with diode change or not.  Later we can propose the solution for your further question.

BR,

AZIZ HASSAN

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Mahdimc1368
Level 1
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Level 1

Hi,

Thanks for the reply. Thank you for your quick response 🙂

Yes, the problem of short circuit by changing the diode has not happened so far.

I am working on another related item Current THD. I am getting good results .

In the data sheet of the module IFCM15P60GD, the maximum frequency of the switch PFC is stated as 60 kHz. And in another part, it is stated that the switching frequency should be set to 40 kHz for optimal mode.

pfc0.JPG

Capture.JPG

I set the switching frequency PFC to 55 kHz and in this case I have the best THD current at the network input.

Is it possible for the PFC switch to be damaged at this frequency (55KHZ)?
Currently, there is no problem in testing with different loads with a current draw of up to 4 amperes from the input (230VAC), only the switching loss has increased a little.

Thank you

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AZIZ_HASSAN
Moderator
Moderator 100 sign-ins 50 solutions authored 10 likes received
Moderator

Hi,

Great to here that.

1) Yes by changing the frequency you can improve your THD and there are  some other methods but this is good enough. 

2) No, the PFC  IGBT (not having any internal anti parallel diode) is good to go till 60KHz. and as you mentioned mentioned correctly, the switching loss has increased, I request you to monitor the temperature and if junction temperature is more than specified then provide cooling.

BR,

AZIZ HASSAN

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Mahdimc1368
Level 1
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Hi,

Yes, I use a temperature sensor NTC in the controller, as well as the internal temperature sensor of module IFCM15P60GD to control and protection temperature of the switches.

I also compare the switching losses at 40 kHz and 55 kHz and get the switching losses added to the whole system.

I really like the infineon company because of its great products and I hope to work there one day.

Thank you very much for your excellent answers 🙂

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Mahdimc1368
Level 1
5 replies posted 5 sign-ins 5 questions asked
Level 1

Hi, 

Unfortunately, due to the fact that I changed anti parallel diode of the switch , there was still a short circuit between pin collector to emitter in IFCM15P60GD (Pin 22 , 23) and it fail,

PFC switch was damaged while working under load.

external diode (BY399 - 800V-3A) is good.just the internal IPM IGBT PFC switch fails.

What solution do you suggest?

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