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First testing until it blew up

A project log for I2C Controlled, FOC capable BLDC controller

The Qwiic BLDC is an open source, I2C controlled/programmed, FOC-capable, ESC and BLDC driver. It's based on Allegro's A98301 IC.

yspace-labsYSPACE Labs 01/17/2023 at 15:340 Comments

I got the boards, soldered the components, and fired it up. Nothing blew up then, but the motor did not work. After adjusting some i2c settings (including turning off OCP (which was not the best idea (although that's what made the motor work (although it may have been because of a shoot-through issue rather than a motor issue)))), the motor jerked around. After adding more registers to my code, I was able to make it jerk better, but I wasn't able to get it to rotate for long at all (only intermittently, randomly, and not many more than 5 turns). I though that maybe another bldc would work better since the one I had came with an esc from Amazon for about $20. (It's a hobby outrunner motor). I borrowed a Neo 550 motor, attached it to the driver, and turned it on. It worked for a short time, but the current limit of my power supply started turning on and off rapidly, and the board started clicking. I plugged in the first motor, but it didn't work. The board just made a clicking sound. It turns out the B phase dual mosfet was shorting to PVCC. I replaced it with a spare dual mosfet, but after running the original bldc for a while, the board made the same clicking sound and the A phase shorted to PVCC. I think that a motor like the Neo 550 needs an insane amount of pulsed current that the mosfets cannot handle because of the motor's low resistance and inductance. Turning off OCP may have allowed this to happen. 

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