SwitchBack DC Motor Drive

[Farmhand]

Hi all, I put together this setup today and it looks like it could be a usefull way to drive a Dynamo machine or other apparatus. Keep in mind it is only a model sized motor but it does draw over 500 Ma how I have it now (restricted) and 1 Amp unrestricted at 12.5 volts. I think any similar arrangement can work to loop the current. I'm trialing capacitors in parallel with the batteries and a few other things.

Video-
YouTube - ‪Switchback Drive.wmv‬‏

The arrangement in the video still has two unused outputs. I hope to experiment with this and some other motors before converting a Quadbike to this system. The transformer can be wound to provide the correct potential and current capability for the apparatus that is to be powered.

I recommend with this particular arrangement to start the transformer first and "prime" the series batteries and the capacitors in parallel with them to about 26.8 volts "13.4 each" not too much though because this way the voltage difference that motor runs from is greater, the single batt drops down and the series ones are up. This can be adjusted aswell for control as when the motor is started it tries to reverse again but it can't if it is reactive.

The transformer contol adjusts Frequency and power from the transfromer to the series batteries and the motor control should be sensed by the transformer control chip to increase frequency under load. I haven't done that yet.

This basic setup exibits some ballancing by the single battery voltage rising it forces more current through the transformer primary to to produce more power.

Maybe it can be done without the series batteries but 1 battery will always be needed for convenience in my opinion, ( I wouldn't like to push charge an electric car).

It seemed usefull so I thought I better start it a thread. I mention in the video that if a system like this was used to drive a Muller Dynamo it could be spectacular. A high current drive motor, but the high current use is negated by the Switch effect, to a degree anyway. It can be done different ways to how I do it to.

Check this thread Started by nilrehob - http://www.energeticforum.com/renewa...apacitors.html - The other guys have good idea's too for similar things.

Here is a quick sketch. Of a basic setup.
http://public.bay.livefilestore.com/...001.JPG?psid=1

Cheers

[Farmhand]

Hi rainandsun, This can work with capacitors in place of the series batteries but it took some very fine adjustment to do it. I think when using all batteries it's best to set it up so it either drains the series ones a bit and charges the single battery or the other way.

Of course some energy is drained from one or the other, in the video I have it set to work both ways, so that if the motor is stopped with the transformer secondary connected the series batteries charge but if the motor is running and the transfomer secondary is open/not connected the single battery is charged by the current through the motor.

I probably didn't do it the best way but I think the idea is workable, for those better at electronics a system using only one battery and capacitors could work well I think.

It could also be done from the negative of the single battery with it's positive joined to the series batteries positive. Difficult to explain without a drawing, I'll make one.

Cheers