Wednesday, October 9, 2013

Electric Motorcycle

How difficult could it be to build an electric motorcycle!?

Kind of difficult.

I bought this 2002 ZX6E from a salvage shop, which had been selling parts off of it for a few years. Salvaged for rod knock rather than crash damage, and for $275, it's a good candidate for the electric conversion. Its aluminum frame is strong and light, and has room for batteries.

Purchased as-is!
With the engine removed and the frame stripped, it's ready for the next step - mounting a motor!



I've got to mount this 4.2 kW motor in the frame, getting the output shaft of the motor as close to the position of the original as possible.

Etek-R
It should sit about here?





I used the rear engine mounts in the frame to mount the motor. I cut and ground and filed 1/4 inch steel to make a mount to accommodate the motor. I bought an old drill press at a yard sale for this job.

I have very little welding experience and no welding equipment, but I was able to fit the bike in my car and my brother taught me how to use his gas-shielded MIG welder.
Pieces cut, prior to welding
Welded and painted!
If it looks good, it doesn't have to do anything, right?
The next step is to build and mount the motor controller. Controllers on the market cost >$300, so I'm hoping to make my own. I found a used 300 amp IGBT module on Ebay, and starting building the controller using copper plate as bus bars with Nippon capacitors across the power rail and a snubber capacitor across the IGBT. The module has two IGBTs in it, and I'm using the EMF protection diode of the second IGBT to control back EMF from the motor.

The capacitors were difficult to solder to the 1/8th inch copper plate, I had to use two soldering irons for enough heat capacity.
Bus Bars and capacitors mounted
With the controller quickly assembled, I tested it for the first time. I don't have a proper gate driver yet, so I'm just driving the IGBT from an IO pin. This test is using 12 volts only, this will be a 48 volt system.


Next is to build the gate driver, mount the IGBT driver in a waterproof box with a heatsink, and install batteries!

2 comments:

  1. What motor did you use and how much did it cost?

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    1. It looks like he used an Me0708, which EVDrives lists as 470 dollars. A common alternative that people use for EVs and has very similar specs is the ME0909, which is a bit longer, but lighter, and goes for about 390.

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