Fault current contribution and short circuit behaviour of a solar PV integrated distribution network

Abstract

This paper investigates the short circuit behaviour and variation in fault level with solar PV integrated distribution network. In order to investigate the issue, a generic distribution network, which supplies power to the load of varying nature is designed and simulated using electrical transient analyser program (ETAP) software. The network is analysed according to IEC 60909 standard and the alteration in short circuit current and fault level due to various types of faults is reported. It is found that the cumulative contribution of upstream and downstream grid makes the three-phase fault most severe in comparison to other faults. However, if the transformer neutral is solidly grounded, then the severity of single line to ground fault will be highest. Furthermore the variation in grid strength considerably affects the fault current level of the distribution network. Such situation is the cause of major concern when solar PV is added to the network.