Aw, gosh, we were just starting to have fun! I read a paper that mathematically modeled an AC induction motor and <insert that margarine commercial sound> the equations were basically the same as for a sepex shunt motor! The basic difference was that for the sepex you directly controlled the field current, and that indirectly controls the armature current and frequency of rotation. For the AC induction, you directly control the field current and frequency, and that indirectly controls the armature current and frequency.
This is part of the reason for good efficiency and broad torque curve for AC induction, you have alot of control over what is happening -- but a sepex motor shouldn't be far behind. --- Victor Tikhonov <[EMAIL PROTECTED]> wrote: > Fine. All these details are obscuring my point that there is > a variable - frequency - applicable to AC motors only. > There is no frequency concept when you deal with supplying DC. > > This is a distinction. > > For Ac frequency converter is outside the motor and solid state. > For DC frequency converter is commutator and is inside the motor, > so its "frequency" is directly tight to the motor speed while > outside inverter for AC can vary frequency infependently of > the shaft rotation. > > This is another distinction. > > Now, if you view motor AND controller/inverter as one black box > as Lee suggested) with pure DC in - there can be no difference. > > Let's end this thread please. > > Victor > __________________________________________________ Do You Yahoo!? Yahoo! Finance - Get real-time stock quotes http://finance.yahoo.com
