[jackbauer]

Hey you got a kilovac! Is that the igbt on the heatsink? If so your going to need a bigger one! I used a 300mm square of 12mm thick aluminium. I like the open source controller board. It works well and saves reinventing the wheel. Building an ev is difficult enough

[Woodsmith]

Hey, more progress, that is always good to see.

It's also good to see my vac pump on your desk.

I am getting tempted to go clutchless and I might copy your coupler design.

[etlaare]

It's so nice to see you all recognize the bits.

And yes the heat sink is too small, it comes from an old robot on my attic and I certainly agree, although they say that mainly the surface counts and not the volume, I will still use a much bigger one, but for testing the controller with low currents I hope the igbt will survive. Unless I find me some more aluminum to make a proper heat sink before that.

I would not consider the coupler to be my design, I copied it mostly from Electric Lemon: http://www.electric-lemon.com/?q=node/213

Almost tempted to give up my skiing vacation so I could keep working on the conversion :-)

[jackbauer]

Keep the starter from the engine. Makes a great "dummy load" for 12v tests of the controller.

[etlaare]

oh... another question though.
Do you have, or have you planned for, an earth leak detector ?
And/or is there a cheap way to make such a device yourself or finding a cheaper one as the £200.00 version I found ?

[etlaare]

Originally Posted by jackbauer

Keep the starter from the engine. Makes a great "dummy load" for 12v tests of the controller.

yes I kept that one, and I also liked your setup with the lamp in your thread

I was looking a little more into safety though and found the intertia switches, but also the earth leak to detect if one of the main power cables touches the chassis. Seems a nice safety in case of an accident, but the only way I know this is implemented is with two coils inbetween the mainstream to drive a core that will switch off when they are not the same forth and back.

Now that would be hard to implement with the currents we are facing here I guess ...

[etlaare]

So happy I found the aluminum so I could get my hands dirty again (and the workshop as well... yes, yes, yes, I will clean it next week, I promise).

[etlaare]

ah well.. I had a skiing vacation in between..
but a little milestone today



with this as the result :-)

http://www.etlaare.demon.nl/firstrun.wmv

no noticeable vibration .. I just hope there's not too much damage doing this without oil for a little while ...
But it was too hard to resist.

[Woodsmith]

Looking good.
It sounds a little rough in the video but that could just be the sound quality. It won't do any harm to run it without oil as it is slow speed, short duration and the gears will still be a little oily anyway.

You progress is good, it woon;t be long before you have it back in the car and turning wheels on 12v.

I still don't have a motor. I was going to go shopping for one but Santa delivered some hefty utility bills so I am £700 down on the EV budget again.

[etlaare]

Yes, the microphone of the camera was quite close and seems to have amplified the sound a bit, but I do agree it could be smoother. I took it apart again and indeed it seemed that the top spline hub was off center for some reason. I am trying to figure out what caused it , it was not much, less than a tenth of a millimeter and it could be just the springs of the connector, but I will do some very accurate measuring before I put it together for it's final assembly (I did not "locktied" it yet).

In the meanwhile I was toying and tinkering a little with my IGBT and I have already put a pwm signal on the motor from my own micro controller.. (the components for the cougar-controller have not arrived yet (I can be so impatient sometimes)). That seemed much easier as I had expected (I used the controller that had been in one of my old (she RIP's) robots which was already programmed for a smooth startup). I am beginning to like this IGBT version, that I think I got as a bargain, quite a lot, it seems so easy to implement, although I did not do any serious measurements to be honest. Yet, while drawing less than 50 amps atm there seems no saturation temperature issue whatsoever. I used a capacitor from the old forklift controller, but I still need to do my maths there.

There were no sensors on the robot-controller so after startup I could not turn it off in a programmed way, then it seemed when I disconnected it, it left the gate in a set state. Hence the motor started running at full speed (well on 24V) and I had to connect the gate to mass to reset it and turn the motor off. I had not expected that, but I guess there's either some capacitor at the gate as well, or the IGBT maybe just acts as a flip-flop which afterwards seems a quite logical explanation too, since the functions it's designed for (DC/AC motor controller and emergency power supply) only needs two states.

I don't have too much experience with IGBT's .. (yet) but I like them.