Lee Hart wrote:
>> We've discussed this before; a DC alternative is still possible.
>> Something like the Porsche 914 that Paul Compton has described on many
>> occassions -- Advanced DC 9" motor with a 240v pack.

[EMAIL PROTECTED] wrote:
> Is this some special, non 144 volt, ADC motor? Wouldn't the motor see
> full pack at some time?

No, it was a relatively normal Advanced DC 9" motor. Paul can tell you
more about the modifications (mainly extra insulation).

The basic trick is that you want to get your horsepower with high rpm
and low current; not with low rpm and high current. Most EVs have
relatively low pack voltages, so at high rpm the motor can't produce
enough torque for high horsepower.

But, you run a very high voltage pack, and turn down the controller's
battery current limit. Now the motor can see high current at low rpm,
but only low current at high rpm. You have what amounts to a constant
horsepower drive (same horsepower at any speed). The motor will be fine,
because it never sees high voltage and high current simultaneously.
--
Lee A. Hart                Ring the bells that still can ring
814 8th Ave. N.            Forget your perfect offering
Sartell, MN 56377 USA      There is a crack in everything
leeahart_at_earthlink.net  That's how the light gets in - Leonard Cohen

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