Study on Inter-Turn Short Circuit Fault of Dry-Type Air-Core Shunt Reactor Under Low Voltage with Low Frequency

When the inter-turn short circuit fault occurs in the dry-type air-core shunt reactor (DASR), the short circuit loop will consume a large amount of active power, which will cause the equipment temperature to rise in a short time and damage the equipment. Therefore, it is very important to detect the fault in the early stage of the inter-turn short circuit fault. This paper presents a method to detect the number of inter-turn short circuit fault turns of the DASR based on modified active power (Pm) and modified reactive power (Qm), at low voltage with low frequency. The formulas for Pm and Qm are obtained by adding correction factors to the formulas for active power and reactive power respectively. Their correction factors are obtained by using genetic algorithm. The variations of Pm and Qm under normal condition and short circuit condition with different turns are studied. The inter-turn short circuit fault with different frequency and different fault location is simulated. It provides a feasible method for detecting the inter-turn short circuit fault of the DASR and determining the number of short circuit turns.