Research on Five-Loop Simplified Scaling Model for Dry-Type Air-Core Reactors With Inter-Turn Short Circuit Fault

In order to simplify the research method of the spatial magnetic field distribution (SMFD) of dry air-core reactors (DARs) in the case of inter-turn short circuit fault, the concept of simplified scaling model was put forward, and the optimal simplified scaling model for different inter-turn short circuit fault was calculated by using the least square method. Firstly, in order to simplify the calculation, 7 typical directions describing the SMFD of DARs were determined based on the similarity degree of magnetic induction intensity in each direction. Then, the simplified scaling model parameters corresponding to different short circuit positions and degrees were studied, and the variation rule was described by using the method of fitting function. Finally, the original model and the simplified scaling model of the DARs in the case of inter-turn short circuit were established respectively in the laboratory. The results show that the optimal structure relative height obtained by experiment is 30% and 20% respectively, which is the closest to the parameters obtained by computer simulation, i.e.,28% and 20.3%.