Phase advance, first report.

Having some time to write a demo program for the motor chip in my controller I tried some phase advance. The first step was 30 degrees using the other side of the bi-directional throttle to give full output 1/2 way and phase advance from 0 to 30 degrees from 1/2 to full. Off load it goes about 10% faster, haven't had a chance to try it on the road, pissing down with rain here in the sunny UK.

Looks promising, and I have devised (in my head at the moment) an add on unit for standard Crystalyte controlers, I might make a few if anyone is interested.

* Raises hand !!!

I'm always willing to try anything new ! ( well.. almost anything :? )

Hi Maxwell

Thats superb!! sounds very interesting, how has this affected the no load amps, how much more does it pull? I can make a phase advance on my motors but the no load amps jumps too high, the RPM is almost doubled though.

The weather is awful and the forecast for tomorrow dont look good, the nearest I will get to e-biking will be one of my videos!!

Keep us notified of the results, also interested to know how you are going to implement this in a xlyte controller?

Thanks

Knoxie

Sounds encouraging. 30 deg. sounds like a lot of advance though.
It would be interesting to see what various advance settings do to the power consumption / efficiency. Advancing it should be almost like gearing it to a higher speed.

Road testing...

A small increase in top end speed with a disproportionate increase in current.

Further reading led me to think this is because the 408 has concentrated windings which are (aparantly) not very ameinable to phase advance. Also the low speed of these motors dosen't help, the fields internaly happen quite quickly and at these speeds are near instantainious.

Could be useful on a geared system with a fast running motor, this isn't!

The down side was so obvious with on the fly mental calculations, I am not going to bother with a quantitatve analysis.

I need a bit more speed, range and hill climbing ability for my 13 mile (each way) work commute, so it is time for a home made Lion pack...


(see another post comming up soon)

yes, what about a slight advance 5 -8 degrees?

5 to 8 degrees, didn't notice a thing.

did you work your way up to 30 degrees? I don't know how much but 10, 15, 20 would seem plausible but 30 must be over the top -- not just an advance but a whole new timing.

It was variable, 30 degrees max.