DIY Alternator Controller

[salty9]

Since Paul & Sabrina seem to have made EcoModder the center of DIY controller development this would seem to be the appropriate forum for a thread for a DIY alternator controller.

I have been planning to build a reverse trike using twin alternators for power and from what I've found on the web people are using them as motors controlled by RC escs. There are claims of power up to 5 HP.

I envision a 10kw max bldc controller with provision to vary the rotor current to control torque. Higher current at low rmps increases torque.

If I missed something in my forum search please direct me.

[dcb]

I've actually been chewing on that myself, main problem is retrofitting hall effects or some other position encoder so you can have nice startup torque. The field draw doesn't look to horrible and may provide for better dynamic range, like sepex does. Also I'm not sure what effect the angled field interface on the rotor will have or the overlapping coils in the stator. Those might be there for smooth power, at efficiencies sake.

[salty9]

Dave,

This is just a counter to reach 5 messages

[salty9]

Dave,

I'm back with a couple of links you might not have found:

Endless-sphere.com • View topic - e-Buggy: Alternator Conversion

Endless-sphere.com • View topic - Adding hall sensors to outrunners

Analysis of a REEM inadvertently used in a reverse power flow condition. - RC Groups

I have not put anything on paper or a breadboard yet but I'm planning on making the controller modular with mcu, optoisolator, driver and power boards.
This should make troubleshooting easier. Lots of little hairballs instead of one big one.

Chuck

[Angmaar]

What would be the advantage to having an alternator controller?

[salty9]

When properly controlled an alternator, like any generator, is a motor. They also happen to be cheap, durable and readily available.

[Angmaar]

Originally Posted by salty9

When properly controlled an alternator, like any generator, is a motor. They also happen to be cheap, durable and readily available.

Oh so you are using it as a cheap motor.

[dcb]

I've dug through this thread a lot too
How to Convert an Alternator to A Motor - RC Groups

but a propeller (glorified fan) is a much more predictable load than a car/bike motor so they get away without position sensing ok at startup



I actually have an alternator that I routed the field and stator leads externally on, sitting on the bench.

[salty9]

I followed that thread quite a while until it got so heated.

I'm planning on using an Atmel mcu as I already have a STK500 programmer. I've ordered an optoisolator board and am trying to determine the mosfets and drivers to use. Any suggestions will be appreciated.

[dcb]

I'm planning on using the atmega 168/328 and borrowing heavily from the atmel site.

i.e. AVR447 Atmel Products - AVR Solutions - Motor Control Applications

Looking to retrofit halls and drive it w/sine waves and experiment with the field strength.

Also found a dirt cheap avr isp clone ($10)
Prototyping PCB I grabbed a pic programmer too for giggles.