Mosfet controller upgrade 
Friday, October 27, 2006, 04:49 PM
Electric cars all seem to want IBGP controllers like the Zilla.
The reason? voltage. The problem? A single IGBT is something like $250/ea
For the motorcycle, 48-72 volts is acceptable. This means that we can use MOSFETs to do the power switching.
Over 80 volts or so, the on resistance goes up - meaning power is wasted, and heat is generated. Low on resistance = cool running.

For my bike, I'm planning to build my own controller. There's a simple mosfet design available on http://austinev.org/evalbum. I snagged a copy and put it at http://biobug.org/ev-motorcycle/controller/circuits/

It's intended for 24-48v and 200-400amps. That's based on the IRF1010. The IRF1010 is rated at 60v, 60A, 130W power dissipation and .011Ohm on resistance. ($1.27 or so at mouser) 4x = 240Amp

I dug around and came up with the Fairchild HUF75545P3. It's rated for 80v, 75A, 270W PD with .01Ohm on resistance. With these fets, it should be god for a 72V system. Not bad eh? ($3.29/ea at mouser)
4x = 300Amp, 6x = 450Amp.
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Motors and models 
Friday, October 27, 2006, 12:16 AM
The perm sounds great - but the price is pretty stiff.
I ran across http://hitorqueelectric.com/ when I was checking out the white zombie ev racer. Frank of hitorque built some nice stuff. I think that I'm going to have him make me up an Advanced DC 6.7" motor. More on that later.

I found a great resource tonight.
http://www.seattleeva.org/

I've also decided that I'm going to build a model version to test with. (Think Back to the Future) I'm going to use it to develop my pwm throttle controller. A seperate module will house the mosfet pack. As the development progresses, I'll will publish the design - full source, schematics, etc. It should be fairly embarassing.

For some reason, the EV community is bad at publishing controller designs. A scanned in low res image just doesn't do it for me.
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Ok, scratch that idea 
Thursday, October 26, 2006, 04:52 PM
I'm not going to rebuild it to run on gas. I poked around the motor a bit. It has good compression, but all four carbs need to be rebuilt, and there are wiring problems, the throttle isn't completely set up properly, and a few other bad things. She's not getting on the road until she's full on EV.

If I do all the work to get it restored, I'll never do the EV conversion. Looks like I'll be selling off the extra parts.
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Sans Title 
Tuesday, October 24, 2006, 11:35 AM
So the free bike has a hidden cost. The title's been lost for years. My friend over at the PD is going to run the vin for me to make sure it's not stolen or anything. Once I know it's clear, I'm going to pay $75 to ITS Titles to get it fixed. I used to deal in older cars, so I know it's the easiest way to get things fixed up.
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Restoring the machine 
Monday, October 23, 2006, 11:15 AM

I got the bike on sunday! It's pretty complete, but in dire need of restoration. The brakes haven't been used in a looooong time. It has front and rear discs, so I get to deal with two hydraulic systems.

The motor has good compression, so I'm going to restore the rest of the bike and get it running before starting the conversion. My time is pretty limited for a while, so it's a good compromise. It's also far, far easier to get it licensed and inspected with the original hardware.

For now I'll post updates as they come along.
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