Adaptto Charge Coil questions

[zlagger]

I was wandering if anyone with more technical expertise could explain how Adaptto's Charging system works. I'm not looking for trade secrets here, just general principles.

For my system, I am presently charging with a 36V power supply. The Battery Voltage has to climb to 83V to reach full charge. So what is happening between the supply, the coil, and the controller?

 

[Doctorbass]

I was wandering if anyone with more technical expertise could explain how Adaptto's Charging system works. I'm not looking for trade secrets here, just general principles.

For my system, I am presently charging with a 36V power supply. The Battery Voltage has to climb to 83V to reach full charge. So what is happening between the supply, the coil, and the controller?

That is using the principle of a Boost converter.

The coil store energy that is pulsed witch icreasse the voltage. the capacitor in parallel with the PSU output is to protect it form the hard high current pulses that the adaptto does. I think.

http://en.wikipedia.org/wiki/Boost_converter :wink:

Doc

 

[cycborg]

To expand on this a bit, keep in mind that, in normal operation, the controller acts as a buck converter. That is, it controls the motor speed by reducing the battery voltage to some lower voltage, using pulse width modulation (PWM) to feed pulses of voltage to the motor windings. The windings are inductive, and this inductance acts to smooth the current from the high-frequency PWM to DC with some ripple.

A boost converter works basically the same way, it's just that the topology is reversed. You still have a PWM switch and an inductor, but the inductor is on the supply side rather than the load side.

So since you already have a sophisticated PWM switcher in your controller, might as well use it. But you no longer have the motor winding to act as an inductor, so you need the charging coil to act as the boost inductor.

Note that this is how regen works - in this case you do still have the motor winding inductance so the controller uses this to boost the motor's back-EMF and inject current back into the battery.

Buck:

Boost: