All N-MOSFET H-BRIDGE FOR 150Amps

[rmayer]

Hi all,

Currently using DPDT relays to reverse polarity on electrochemical cells. We are wanting to FET the power to them to be able to PWM the power and periodically reverse polarity. I found some circuits where all N-MOSFETS were used by driving the ones on the high side with a larger gate voltage. Only real questions here are...

*Has anyone built a MOSFET H-Bridge in this capacity range?

*Anything to look out for in paralleling this many MOSFETS?

*Recommendations on putting all of the D and S of the MOSFETS on common rails or busses?

Check out the basic schem but know that the parallel arrays are represented by only single MOSFETs

 

[itsmoked]

Not hard paralleling one FET.

Go to IXYS and look around.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[ScottyUK]

If this is a high voltage design then IGBTs are likely to be a better solution. If it's low voltage then MOSFETs are likely to be better. Check out the packaged modules from Semikron and I-R in addition to those from IXYS suggested by Keith. 150A rating isn't that high - I-R's range goes above 400A.


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If we learn from our mistakes I'm getting a great education!

 

[rmayer]

Low voltage ~10-15V
Forgot to mention that

 

[LionelHutz]

I've seen DC motor controllers (forklift or golf cart type of thing) with many parallel TO-220 package mosfets in them.

But, as already posted, there are some high power devices out there. IGBT's in VFD's are typically in a 3-phase or 3-H bridge package. When higher power is required 3 packages are used with the devices paralleled.

So, should not be a problem, but still, if you do parallel devices you have to be very careful of the resistance and inductance of your busswork to make them share.

 

[itsmoked]

That makes it much easier yet and MOSFET territory, not IGBT.

Check this thread: thread238-243033

Keith Cress
kcress -

http://www.flaminsystems.com