Successful induction motor test

["Arthur Matteson" <fanofca@hotmail.com>]

Dear fellow AC'ers and EV'ers,

Today I tested my (TI's) space-vector code with my system, with 120VAC one-phase in and 115VAC three-phase out, on a 3/4HP motor.
It is very impressive.  To my surprise, regenerative braking worked without me even trying - I forgot about it when I first turned
down the speed.  You can really slow down the shaft quickly.  I measured the voltage on the bus capacitor (3300uF) jumping up from
165V to 225V when I turned the speed down even at a medium rate.  1800 RPM is fast, but 3600 is really whizzing along.  So far this
project has been a piece of cake.  I haven't had any problems with anything.  The IGBTs don't even get warm.  The TMS320F241 works
very well, but it has a few bad resets once in a while.  Any suggestions to replace the 1K pullup (or pulldown, I forget)?

I've just completed my subwoofer amplifier - 500-600W maximum power, class-D, from 12V.  I realized that I was using a powder core
before, and getting bad results; the new ferrite works beautifully.  I didn't even bother to make a digital regulation circuit - I
just used the UC3525's op-amp (PWM).  I'll expand this power supply onto my 4" core(s), when the rest arrive.  I can't do much with
only one side of a U-core.  They should have sent me 12...whatever happened to our deal...got to call them again...   In the mean
time I'll work on the DC-DC converter and charging circuit, since I have the cores for those, and plenty of IR2184s.

Anyone who wants the software or the plans for the circuit, or anything else, can just contact me.  (Please don't use my
awmatt@mediaone.net, since it is going away tonight.  ComCrap hasn't been able to add me as a user yet, so just use
fanofca@hotmail.com.)  This circuit would be workable for a simple open-loop AC induction motor controller - you could make a decent
EV out of it.  I don't have any plans for my cooling plenum; I don't really feel like drawing it up, and it is quite customized for
my project.  It's not really anything worth drawing up.  However, the circuit board design is done, and in AutoCAD 2000.

Note to Lee Hart: Thanks for the warning about the softening plastic - I have decided to get nylon washers and screws, which should
prevent any softening.  I have already tried the washers, and they insulate very well and don't melt themselves.  Next time I'll try
to find a material that won't soften as easily, but I'd like something see-through, if for no other reason but displaying it.

Just checking in,
Arthur Matteson
-- '80 Lectric Leopard
-- Homebrew induction drive (soon)
-- Ann Arbor, Michigan