Haeri - Tehran Regional Electric Co. IRAN

Pole slip is a phenomanon which whenever occurs, the generator goes under a sever oscillation of torque as weell as large variation in current, voltage and power rector. The pulsation torgue produce and the consequence stress due to this trque is so hight that during the first cycle of pole slipping the generator has to be cut off from the system and possible damages considered. Almost all the old generators are not protected against this destructive phenomenon and so this is very obvious that the bigger generators have to be equiped with pole slip protection and for the smaller generators some works must be done to reach a reasonable safety margin.