Re: [SI-LIST] : coming up with average power estimates for

Steve Weir (
Tue, 03 Aug 1999 20:10:26 -0700

You can find print on this stuff in power electronics literature. I think
you and others have reinforced the fact that Pat needs to realistically
characterize his load profiles. If this is all a bunch of DSP stuff
crunching continuously, I don't think he will have any patterns which get
into the msec or slower range, where thermal time constants will start to
effect the peak versus average temperature rise at the die.

Kollmorgen used to have the problem you refer to with their printed motors.
They had great acceleration characteristics, but without a substantial
thermal mass in the rotor, could not sustain significant overdrive without



At 08:27 PM 8/3/99 +0100, you wrote:
>O'K for short time intervals and small systems. One of the problems with a
>large sytem consuming power on this scale is than it is dangerous to assume
>that you know the peak demand well from the study of relatively small samples.
>I designed some air gapped, iron cored power frequency inductors using your
>principle many years ago, I have never seen similar in print. However,
>physical inductors corresponded to calculations well. One is still in use
>in my
>arc welder.
>Best wishes
>"S. Weir" wrote:

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