I prototyped a water cooled MC to see if I could get a little more performance out of the VX1. I was looking mainly to get a little better bottom end acceleration.
To get a quick idea if it would help, I wired the radiator fan and water pump to run constantly. Then I modified the SW to allow: more phase current, more bus current, faster ramp up of throttle signal, higher gain in current loop. I tried various combos of these variables.
Result: no improvement. Any time I increased the phase current I would get the IGBT fault (the one where it sounds like motor is grunting). I guess the bottleneck is not in getting the heat out of the IGBT base, but getting the heat from the transistors to the base. So I will revert back to the fan cooled heatsink.
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I seem to remember when I first picked up my 2007 bike it had SUPER gutsy power, couldn't get the front wheel off the ground, but it felt like I almost could. Then the dealer put an update on it claiming it would prevent battery failure and no more guts. I am happy with how the bike goes, but always wondered if the bike was really built tough enough to handle the power it had onboard.
My battery of course went on to fail anyway, this was after Vectrix had gone belly up, but when they reformed I got one of the first new packs in the Bay Area. Still working great to this day. (well, didn't actually try it today)
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I also own a 2018 Tesla Model 3 and a 2012 Mitsubishi iMiev
My guess is thats when we raised the minimum pack voltage. All the gains and acceleration parameters have always been the same for all bikes sold.
Your original SW probably generated more phase current b/c bus voltage was allowed to go lower.
With a Li pack I am satisfied with the performance as is, was just curious if I could get it to lay rubber. But nope.
Why? would you want it to do that??? IMHO keep the rubber where it belongs: on the tire! ...unless, of course, you like changing tires...
great job . a pity that it didn't work. And with the FW modifications, what would be the max power before failure?
I bumped up the phase current from 375 to 450 in increments. Never really noticed any acceleration improvements. Then at 450 I started to get faults. I guess thats all the engine has to give, probably just saturating the field.
BTW, these were parts left over from Vectrix days, but we never got a chance to try it out. Been sitting in my garage for 10yrs.
Any chance of the IGBT module getting redesigned to use more modern component's?