1996-07-13

Zapped!

Sorry, no pictures again.

I have some good news and some bad news:
The good news is that while playing around with the programming and making some meter readings the Zapi Regen circuit started working!
The bad news is I don't know what "fixed" it or why it was broke, but on the other hand I haven't been able to break it again. (not that I'm trying all that hard)
Took a short test run using regenerative braking. V E R Y interesting! I can't wait to use it more and get some experience and comments to pass on, but it sure was nice to see juice going back into the batteries while coasting down a hill!

More bad news: after over a week of using and recharging my EV, the Zivan charger bit the dust. Don't know for sure what caused it, but an hour after I plugged it in one night I came back to find it dead. Both fuses were blown (oddball fuses at that) and after further investigation the input bridge rectifier was found to be shorted out. Asking around I found a few cases of this happening to other folks. The assumption is that the bridge rectifier that comes built in isn't very beefy.

So, while the EV is down and out without a charger I've taken the opportunity to take it partially apart again. The reason this time is to reset the motor advance so it will work better with regen. These motors come with the brushes advanced slightly (in relation to field coils) to provide a slight economy, I believe, in regular forward propulsion. Well, when you start using the motors as both a motor AND a generator this advance setting suddenly becomes the opposite when in regeneration, which can cause arcing and sparking. So I've adjusted the motor (and the end motor mount) to be on the zero advance setting.

I'm also blocking some of the airflow (streamlining?) and making a special air "path" to blow across the underside of the controller. Unlike a gas powered car I only have a small, focused amount of waste heat to disperse. If you read the press release for GM's new EV1 electric car you'll find that it is extremely streamlined, in fact the whole bottom of the car is a smooth, continuous surface: no excessively hot mufflers to worry about.