So I was doing some digging on the new STM32 chips, looking for something that would allow the firmware to run at over 60khz.
This looks like a really good fit: STM32H743
It's 4x faster, smaller (0.8mm BGA) and has a bunch of extra onboard features that would make it excellent for running a motor controller at much higher frequency, the idea being that we might be able to get switching up to a speed where GaN makes a bit more sense and all the big electrolytic can be removed.
AFAIK the only thing stopping VESC going faster is running out of processing power on the little M4 core, I think the peripherals are good enough to go faster.
Obviously doing the port is going to be quite involved, version 19 of ChibiOS supports the H7xx chips so I think its more a case of moving VESC code to that version. After that its probably not too difficult to change to a different chip. I am a bit confused why we are still using a version of ChibiOS from like 2015.
I have ordered a Nucleo board for the STM32H753ZI (same as the 743 but has a crypto module) so I can start looking at this. Fingers crossed it's not months of work! If anyone wants to help that would be grand.
|Clock speed||168MHz (210DMIPS)||480MHz (1027DMIPS)|
|ADC||3x 12bit 2.4MSPS (7.2MSPS)||3x 16bit 3.6MSPS (10.8MSPS)|
|Timers||2x 16bit Motor Control Timers (168MHz)||2x 16bit Motor Control Timers (240MHz)|