300A VESC in the works, feature suggestions wanted

[TechAUmNu]

Boards arrived this morning!20170805_124723.jpg
Sneaky preview of the thermal cameraThermalCamera2017-08-04_19-11-05+0100.jpg

[TechAUmNu]

Spend the day working on getting one of the half bridges working. Ended up going through quite a number of gate drivers until I realised that I was putting them on the board the wrong way round oops! Using an Arduino Due to generate a differential 8kHz signal for testing.

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Now that I have one working half bridge I can test out various values of gate resistors to keep the inductive spikes down and reduce the emi from the board. Once I find a usable value I will then populate the other 2 phases and wire it up to an old vesc to see if it will do anything.

The quality of the boards is excellent for how cheap they were.

[Ellis]

I like the rate of progress here. Keep it up, it's exciting!

[shakesc]

Sharp edges on switching, what every happened to mushy ramps and slushy drivers

[TechAUmNu]

Today I switched over to 22ohm gate resistors as a test of worst case for slow switching, I can speed it up again later if it loses too much power but it gives a nice smooth turn on with no ringing which makes it perfect for testing as it doesn't generate loads of noise.

You can see the difference on the scope: 20ns for 1ohm, 50ns for 22ohm
1Ohm.png22Ohm.png

Got a full set of parts on now so I can start doing some testing!

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[Rapidrory]

Oh no... 50ns... how ever will you cope...

*looks at his 1000ns rise times and cries*

[Ellis]

Lol, the majority of shiity Hobbyking-breed ESCs are like 5us, so you're orders of magnitude better than the average!

[maddox10]

Ellis, I have a secret for you. The semi indestructable Tz85's, are basic "el cheapo Hobbyking ESC's".

[TechAUmNu]

Logic boards are done and shipped on Wednesday so should be here sometime next week.

I have had very little time to work on this the last few weeks with 2 weddings! So should make some better progress this week.

My plan is to have it running a small motor by the end of the week and gradually increase the size until I get it to run the 150cc rotomax.

We have also decided to redesign Triforce slightly and will be using the 50cc rotomax for our drive. This means Triforce will be running 4 of these speed controllers when we apply for next series! So should be a good test for them if we get on

[TechAUmNu]

Turns out I had another error in my spreadsheet so in actual fact this controller should handle 450A 16s just fine which puts it peak output at over 30kW lol. Talk about overkill.

[Maxamuslead]

Talk about overkill.

best type of kill

[shakesc]

Should be good for my Neumotors then

[maddox10]

It seems I want to try one.

[TechAUmNu]

Managed to get round to working on it some more tonight. I found out I don't have any wire thin enough to solder onto the tiny pads on the vesc so I just wrote some simple bldc commutation code for arduino to see if it worked.

One thing I figured out is that I need a bigger powersupply lol.

With a slow ramp up it does get reasonably fast.

I also settled on calling it the A450S

[TechAUmNu]

Logic boards arrived. 40 is quite a lot...