EXPOSITION OF FAILING OF CIRCUIT BREAKER ENGAGED FOR SWITCHING OF CAPACITOR USING SOFT COMPUTING

In several parts of power system, we may experience the pockets having low voltage and low power factor problem due to more share of inductive load in total load fed by the EHV sub-stations. In such pockets, the system strengthening can be done by several ways such as addition of new transformer capacity, smoothing of load curve by way of load management, maintaining LT-HT ratio etc. These measures may require exuberant time. The measure that can be adopted for system improvement within minimum time span is the installation of capacitor bank across the buses of EHV sub- station which feeds power in low voltage and low power segment of grid. The addition of capacitor bank in EHV-HV system, improves the power factor and voltage considerably, thereby reducing reactive power burden of system. But the switching of capacitor bank on an energized system will generally result in a transient voltage and increases the possibility of failure of circuit breaker engaged for its switching earlier than its specified operations. Practically many such occurrences were noticed in EHV-HV substations where capacitor banks have failed during switching and also before attaining their prescribed number of operations. With the large scale development in Artificial Intelligence technology, sophisticated and accurate soft computing technique are coming up. Hence, effort is taken to examine the causes for failing of circuit breaker engaged for switching of capacitor bank using soft computing approach. Prototype experimental model of 132/11KV Sub-station is developed using MATLAB Simulink and circuit breaker failure analysis is done by using soft computing algorithm.