The Extraction Of Fault Feature Of Winding Inter-Turn Short Circuit In Doubly Fed Induction Generator

With the reduction of coal,oil and other non-renewable energy sources and the continuously deterioration of environmental problems,such as wind energy,solar energy,geothermal and other clean energy have been paid more and more attention to.Wind energy,as one of the most common clean energy,is mainly used through wind power generation.Because the doubly fed induction generator(DFIG)is the major type of wind power generation,so the research of its common inter-turn short circuit fault plays an important role in maintaining the stable operation of the generator.Based on the multi-loop theory,the mathematical model of DFIG is established by MATLAB software,and the simulation analyses are carried out on the normal condition,the stator inter-turn short circuit and the rotor inter-turn short circuit.Harmonic analysis is one of the important research directions in the study of winding inter-turn short circuit fault of doubly fed induction generator in the past.After the occurrence of inter-turn short circuit fault,the stator winding and rotor winding will produce certain number of the harmonic component.When the stator inter-turn winding short circuit fault happens,the rotor side current is taken as the fault characteristic quantity,and the stator side current is taken as the fault characteristic quantity while the rotor inter-turn short circuit fault occurs.Analysis of fault characteristic harmonics can effectively monitor and analyze inter-turn short circuit faults.The traditional harmonic analysis methods are FFT and wavelet analysis,and there are some defects in the process of fault diagnosis.To make up for deficiencies,the Prony algorithm and differential algorithm are introduced to solve the problem of FFT fence phenomenon;while the combination of MUSIC algorithm and a series of optimization algorithms is adopted to solve the problem of spectrum leakage.The results of simulation data obtained by using the above methods were analyzed and show that the new algorithm has a great significance of improving the diagnostic precision and speed of stators short-circuit fault of DFIG.