Salient Pole Synchronous Motor
Salient Pole Synchronous Motor:
- Cylindrical-rotor synchronous motors are much easier to analyze than those having salient-pole rotors. It is due to the fact that cylindrical-rotor motors have a uniform air-gap, whereas in salient pole motors, air-gap is much greater between the poles than along the poles.
- Fortunately, cylindrical rotor theory is reasonably accurate in predicting the steady-state performance of salient-pole motors. Hence, salient-pole theory is required only when very high degree of accuracy is needed or when problems concerning transients or power system stability are to be handled.
- The d-q currents and reactances for a salient-pole synchronous motor are exactly the same as discussed for salient-pole synchronous generator. The motor has d-axis reactance Xd and q-axis reactance Xq. Similarly, motor armature current Ia has two component: Id and Iq. The complete phasor diagram of a salient-pole synchronous motor, for a lagging power factor is shown in Fig. 1 (a).