Motor: power production, Electrical Engineering

The mechanical power produced at the armature of a motor is: P = Ta .

(power is in watts if torque is N.m and    in rad/sec).

Some of this will be lost due to friction and air resistance ('windage'). The remainder is available as mechanical output power.

This leads to two Torque definitions:

Ta is the so-called 'air-gap torque' produced by the armature

Ts is the 'shaft torque' that is available to drive the mechanical load

The difference is that lost due to friction, windage etc.

The input electrical power that is converted to mechanical power at the armature is that due to the product of the back emf and the armature current.

Note that e is smaller than the applied voltage, V.

In addition to mechanical losses (friction etc), some electrical power is dissipated in the armature resistance and field coil resistance. (In an ac motor, other losses occur due to magnetisation and eddy current losses).

Hence, for a shunt connected motor:

Ta.      = e . Ia = (V - Ia.Ra) . Ia

218_power production.png

while for a series connected motor:

Ta.     = e . Ia = [V - I.(Ra + Rf)] . I

1891_power production1.png

Posted Date: 8/27/2012 7:03:34 AM | Location : United States

Related Discussions:- Motor: power production, Assignment Help, Ask Question on Motor: power production, Get Answer, Expert's Help, Motor: power production Discussions

Write discussion on Motor: power production
Your posts are moderated
Related Questions
Task a)    Investigate and describe the significance of the following: i.    Slenderness ratio and buckling in columns ii.    Effective length of columns b) Explain Eu

NPN BJT with forward-biased: An NPN transistor can be referred as two diodes along with a shared anode. In common operation, the base-emitter junction is forward biased and th

Experiment • Wire the circuit shown in Figure. Connect the three oscilloscope channels as shown in Figure. • Select the sinusoidal waveform. Adjust the frequency of the input volt

Impurities in Semiconductors Can be added in accurately controlled amounts. Can modify the electronic and optical properties. Used to change conductivity over wide ra

Tick off the material, which is different from the group (A) Constantan.            (B) Manganin. (C) Nichrome.               (D) Brass. Ans: Tick off the materi

Application of Microprocessors Microprocessor microcontroller based systems  may be used  in almost  every filed of life  and  their  applications  are increasing day by day

Q.  Define coil pitch, Back pitch, front pitch, pole pitch, commutator pitch, resultant pitch, Multiplex winding and degree of Re-entrant of a winding, with respect to a D.C. mach

Q. Explain about blocking probabilityand Grade of service? And what do you mean by delay systems in telecommunication networks? Ans: Grade of service: In loss systems, traff

Buck Boost Converter The output  of buck boost  regulator may be  less than  or greater than the  input  voltage. Since  the polarity of output  voltage  is opposite  to that