Abstract：The open-circuit faults of the converters in wind energy conversion system will seriously affect the operation of the system. In order to improve the reliability of the system, it is necessary that demands the system can timely detect faults and accurately diagnose the faults’ position. This paper presents a diagnostic method for an open-circuit fault in the two power converters according to the variations of fautly current. This method detects faults based on the variations of current Park’s vector phase, locates fault’s position according to the range of motor-side average current Park’s vector phase and the positive or negative of grid-side each phase current. Simulation and experimental results verify the validity of the proposed method, besides this method has the robustness against disturbance such as load transients, grid voltage sags.
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2015, Vol. 30 
