1
\$\begingroup\$

I've been working on a BLDC control circuit for my senior year project. Recently I confronted a problem and couldn't solve it after days of googling which is quite frustrating for me. Here are some details.

I use IR2130 mosfet driver -controlled by an arduino- for 3 phase H bridge.

High side PWM signals can reach 90% max duty cycle.

I use IRL540 Logic mosfets which have 16v Vgs voltage. (I have 12v rectifier)

This is the curcuit I use. I simplified it by drawing only 1 phase other phases are present in real circuit. Simplified circuit diagram

My questions (problems) are:

1- My arduino generated input signals are fine but IR2130 doesn't generate High and Low side mosfet signals.

2- I grounded both arduino and circuit on the same GND still no effect on it. Is it necessary?

3- I suppose Vso pin is necessary to discharge Mosfets. So I grounded it using a small resistence. Am I doing right?

4- Even if I messed up the bootstrapping, shouldn't low side mosfets work just fine?

Any help would be appreciated. Thank you!!!

\$\endgroup\$
  • 1
    \$\begingroup\$ This circuit is wrong. Compare your circuit with some application note IR2130 or similar circuit you can google. \$\endgroup\$ – Marko Buršič Mar 26 '17 at 16:10
  • \$\begingroup\$ Could you please tell me what is wrong in this circuit? I can't compare it to other circuits because others are way too complicated for me. \$\endgroup\$ – szryxl Mar 26 '17 at 16:18
  • \$\begingroup\$ I think if you are not using the current sense you need to tie ITRIP to ground. Check the /FAULT pin, I think you will find it is low. Once it is in fault you need to set the inputs to all off to reset it I think. \$\endgroup\$ – Trevor_G Mar 26 '17 at 16:22
  • \$\begingroup\$ LIN1 2, and 3 high Maybe. \$\endgroup\$ – Trevor_G Mar 26 '17 at 16:27
  • \$\begingroup\$ You have almost all pins at the right side not connected, MOSFETs don't have gate signals. \$\endgroup\$ – Marko Buršič Mar 26 '17 at 17:19
1
\$\begingroup\$

Make different ground (at least by names) The power ground is Vso, th logic ground is Vss. The minus of the battery goes connected to Vso, while the the arduino GND goes to Vss. Now you have two systems completely separated - power-> high current, logic->small currents. Now you need to to join these grounds to same potential by connecting a short or a shunt resistor in case you will be monitoring the current as well.

EDIT: Your circuit lacks the ITRIP connection, so this could be the main issue. enter image description here

enter image description here

|improve this answer|||||
\$\endgroup\$
  • \$\begingroup\$ ITRIP was the problem I didn't realize it was crucial. Thank you so much! \$\endgroup\$ – szryxl Mar 28 '17 at 13:02

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.