Guys,
I've been thinking about something for e-bikes that Tesla/AC Propulsion cars have. Wouldn't it be nice to have a device that:
- Steps up/regulates battery voltage. Your pack could live at 41-25V and regulator would boost it to constant 72V
- Regenerates bracking energy and recycles it back to the capacitors/battery
- Works as a charger and accepts home 120v/240v AC current
- Buffers battery load so that battery is discharge using average power not seeing power peaks on acceleration/etc
It seems to me all of this can be done with buck boost regulator and some switches/rectifiers. That's in theory
Regulator would have to be able to accept 0V-240V voltage and output voltage required by motor/battery charging. Circuit invitingly simple:
http://en.wikipedia.org/wiki/Buck-boost_converter
All you need is then FETs for switching, inductor and capacitor. Capacitor would be ultracap if energy buffering is needed. All switching would be then controlled by microcontroller. I have all the parts except inductor. digikey doesn't seem to have anything that would handle 40Amps that would be needed. I'm thinking to gut big transformer from say 240V-120V voltage converter and rewind it. Would this work? Would efficiency be horrible?
Bellow is a general schematic of the idea:
I've been thinking about something for e-bikes that Tesla/AC Propulsion cars have. Wouldn't it be nice to have a device that:
- Steps up/regulates battery voltage. Your pack could live at 41-25V and regulator would boost it to constant 72V
- Regenerates bracking energy and recycles it back to the capacitors/battery
- Works as a charger and accepts home 120v/240v AC current
- Buffers battery load so that battery is discharge using average power not seeing power peaks on acceleration/etc
It seems to me all of this can be done with buck boost regulator and some switches/rectifiers. That's in theory
Regulator would have to be able to accept 0V-240V voltage and output voltage required by motor/battery charging. Circuit invitingly simple:http://en.wikipedia.org/wiki/Buck-boost_converter
All you need is then FETs for switching, inductor and capacitor. Capacitor would be ultracap if energy buffering is needed. All switching would be then controlled by microcontroller. I have all the parts except inductor. digikey doesn't seem to have anything that would handle 40Amps that would be needed. I'm thinking to gut big transformer from say 240V-120V voltage converter and rewind it. Would this work? Would efficiency be horrible?
Bellow is a general schematic of the idea:
