Comparison Using Distance Relays with Rotor Speed & Acceleration Variation algorithm for Identifying and Predicting out of Step with PMU

Transient stability is one of the major threats for distributed generators security. Instability of a generator causes it becomes out of step with respect to the system. Out of step of a generator can result into two hazardous mechanical and thermal effects. Therefore, in the case of out of step, rapid disconnection of generator from grid is very essential for generator protection. For this purpose rapid detection of out of step condition has been studied for long times. In this paper, a new algorithm is proposed for predicting out of step condition. In this algorithm, by tracking speed and acceleration of a generator, their locus can be obtained in the speed-acceleration plane. Movement of the speed-acceleration locus in the plane can give us a measure for detecting and predicting out of step condition. The proposed algorithm is verified on the generators of IEEE 39-Bus.

Keywords:

Transient stability , out of Step , mechanical and thermal hazard , rotor speed , rotoracceleration , prediction