Recent content by district9prawn

Is something still wrong with the site? I can access it but images and buttons are not showing so it is hard to navigate and checkout an order. I am on pc but it looks the same on my phone. Also bummer to hear that demand is low and 18650 will not be getting restocked.

The small tension wheel by the front sprocket isn't enough. It just helps the chainline clear the bottom bracket shaft. I ended up using a spring loaded chain tensioner. 25H chain should work fine for those rickshaw motors.

I've also been playing with silent HFI for sensorless tracking at low/zero speed this week as this has recently been added to the vesc firmware. I have it configured to inject in d-axis at half the switching frequency so it isn't totally silent at 15kHz but not an issue on the road. It works...

I blew the power board on the V2 controller this week. I'm pretty sure it was my fault. I disassembled the controller to check for water ingress as I had done a lot of riding during wet weather recently. I forgot a few screws and a week later, the mosfets under the missing screws blew :oops...

This seems to be a pattern of behaviour with Flipsky. Very similar (but not identical) hardware emerges some time after they presumably get their hands on a design. Then they are not very forthcoming with firmware. A couple of years ago I asked them if they planned to sell something higher...

Could send the encoder signal to a microcontroller and output emulated halls?

Should be ok to track rapid acceleration of a small motor with a reasonable loop freq. Haven't tried on real hardware though. Another problem is that it will track 180 degrees out of phase in the reverse direction so need some logic to check speed and adjust sign of the summer to ensure smooth...

A quadrature PLL like this seems to do the trick in simulation. Output is speed, which you can integrate to position. I would like to try sensorless foc on an stm32h7 and play around with some algorithms.

Nice work with sensorless foc and porting to the F405. I will definitely give it a go since it will work with existing hardware. Since you are integrating the bemf and calculating atan2 anyway, would it be worth implementing a quadrature PLL to track angle with better noise immunity.

The formula to calculate flux linkage is 60 / (2*pi*sqrt(3)*p*kV) where p is pole pairs.

If you enter in your correct flux linkage value manually are you able to spin the motor in foc?

Due to the higher input voltage, it will most likely use low side current shunts and discrete gate drivers, as opposed to the DRV chip in the v4 and v6 hardware. The controller losses will not be different when running at say 25% and 50% duty, assuming phase current is the same. Switching...

No way its capable of continuous 100A battery current. Curious to see if it is really 20s capable.

The literature seemed to be mostly 6 step commutation examples and simulations. I suppose it would be a useful technique if that was all your micro was capable of.

I've been using it almost daily since July 2020 when I posted it so it seems ok for my setup at least. Benjamin recently put out a dev firmware with field weakening so probably best to give that a go.