Study of rotor winding inter-turn short circuit fault in doubly fed induction generator based on current signal spectrum analysis

Rotor winding inter-turn short circuit fault is one of the common faults of doubly-fed induction generator (DFIG), so the fault diagnosis is great necessary. This paper described the causes and hazards of the inter-turn short circuit fault, analyzed the variation regulation of the electromagnetic properties, and established a multi-loop model of DFIG in cases of fault of rotor winding inter-turn short circuit and in normal conditions. Then the multi-loop model was used to simulate 5.5kW DFIG which was in normal conditions and in cases of fault of rotor inter-turn short circuit, respectively. Fourier transformation was applied to analyze the harmonic variation of current in cases of faults, and current spectrum features was summarized. The work is significant to research new protection program, protection criterion and to improve design and manufacture.