Evaluation and performance comparison of power swing detection algorithms

This paper presents performance comparisons and evaluations of several power swing detection algorithms. Any sudden change in the configuration or the loading of an electrical network causes power swing between the load concentrations of the network. In order to prevent the distance protection from tripping during such conditions, a power swing blocking is utilized. The decreasing impedance, the Vcos/spl phi/ and the superimposed currents methods are conventional algorithms for power swing detection. In this paper, the behavior of these algorithms is evaluated. Different conditions have been generated by EMTDC software and voltage and current waveforms have been given to the power swing detectors. Operation of the power swing detectors has been investigated for different conditions and the operation of different algorithms are compared.

I. INTRODUCTION

The principle relation of protective relays to the problem of power stability is their vital role in clearing faults as rapidly as possible in order to maintain stability. The opening of a sound or healthy line, during swings from which the system can recover, is nearly always undesirable. It is apparent that relays should be required to distinguish normal conditions, short circuits, swing of large amplitude and out of step operation. They should also take the desired action at the right time in each of these circumstances [1].