The speed regulation of a motor expresses how much its speed varies between no-load and full load. The synchronous motor runs at a constant speed whose magnitude is dependent on supply frequency and the number of poles. Since the speed of the motor is constant hence its speed regulation is zero. Under no-load conditions with normal excitation, armature current Ia drawn by a synchronous motor lags the applied voltage V by a small angle.
The tendency of a Reach of Distance Relay to operate at impedance larger than its setting value is known as overreach. Overreach is the presence of d.c. offset in the fault current wave, as the offset current has a higher peak value than that of a symmetrical wave for which the relay is set.
Bus Type - Known Parameter - Unknown Parameter Load Bus -P, Q - V, phase angle Generator Bus - P, V (magnitude) - Q, Voltage phase angle Slack Bus Voltage - magnitude and phase angle - P, Q