Short Circuit Fault Analysis of Electrical Power System using MATLAB

Abstract

The objective of the present study is to simulate short circuit faults on different buses of a power system network and to estimate the state of the power system before and after a fault, which includes various bus voltages and current flow on various transmission lines. The analysis before the fault is carried out by solving non-linear load flow problem by using numerical iterative technique of Newton-Raphson method. State estimation after short circuit fault is carried by using algorithm of short circuit current computation. The short circuit currents dictate the rating of circuit breakers to be employed at various buses and in various lines of the network. The effect of three phase short circuit faults on power system has been studied in terms of post-fault conditions and pre-fault conditions. In this paper, three phase short circuit fault is simulated on the standard IEEE 11bus and IEEE 30 bus system and fault current level is calculated and short circuit MVA rating for the circuit breaker has been chosen. The analysis of power system under faulty conditions is important to determine the values of system voltages and currents during faulted conditions, so that protective devices may be set to minimize the harmful effects of such contingencies.