New Method of Capacitors Failure Detection and Location in Shunt Capacitor Banks
Shunt capacitor banks are critical assets. Exposure to sharp temperature variations, transient over voltages, aging and manufacturing defects can cause internal failures of capacitor elements. This paper discusses a method within a digital relay using indicating quantity Superimposed Reactance (SR) to locate capacitor elements failures in shunt capacitor banks (wye-ungrounded and wye-grounded). The proposed Superimposed Reactance (SR) method adopts calibrating factors for fault location and can provide live report of the number of failed capacitor elements. Advantages of the proposed method reports over conventional unbalance relaying alarms are also reviewed using a commercial relay test results comparison.