Detection method of inter-turn short-circuit magnetic field of air-core reactor based on wavelet analysis
To solve the problem of insufficient sensitivity and accuracy of the current dry-type air-core re-actor inter-turn short-circuit detection method,according to the abnormal change of the induced voltage of the detection coil during the fault development period,a new method based on wavelet analysis was pro-posed to detect the inter-turn short-circuit magnetic field of the air-core reactor.Firstly,the voltage signal of detecting coil in the reactor fault development stage was simulated and analyzed,and the signal varia-tion characteristics of detecting coil in the short circuit between turns at different positions of the reactor were obtained.Based on the principle that the relative ratio between useful signal and noise is the largest in the wavelet coefficient of signal decomposition,the optimal wavelet basis function was selected layer by layer adaptively.The wavelet transform was used to de-noise the signal threshold value,and the fault characteristic was extracted so as to timely and accurately judge the development period of the short cir-cuit between turns of the reactor and avoid the further development of the fault.The sensitivity and relia-bility of the magnetic field detection method based on wavelet analysis were verified by building an experi-mental platform for the detection of inter-turn short-circuit fault of the reactor,which provided an effective guarantee for the safe and stable operation of the reactor.
万方数据
维普
