Capacitor banks contribution to arc-flash applications to solar and wind farm substations

Abstract

IEEE Std. 1584 specifies that capacitors must be part of the arc-flash study. The software tools generally adopted for analytical studies are not suitable for the calculation of the arc-fault incident energy in the presence of capacitor banks. The reason for this deficiency is that the model of the electrical network is only valid for the analysis of short circuit currents at the fundamental frequency. The frequency of the outburst current from a capacitor bank is determined by the size of the capacitors and the impedance of the conductors connecting the capacitor bank to the fault. Given the large power ratings of capacitor banks at the substation of solar and wind farms, it is important to develop a method to determine the maximum contribution from these capacitor banks to the arc-flash incident energy.