Comparative Study of Offline Detection Methods of Static Eccentricity for Interior Permanent Magnet Synchronous Machine

This paper proposes and compares detection methods for the presence of static eccentricity in Interior Permanent Magnet Synchronous Machines (IPMSM). Three methods are proposed. The first method is based on commanded voltages that uses shift in the voltages in d-q plane to detect fault. The second method is based on the incremental inductance that uses shift in peak of the curve for fault detection. The third method uses the combined information present both in current and voltage harmonics to detect the fault. This makes the detection scheme robust with respect to current controller bandwidth. It is shown that all three methods are capable of detecting presence of static eccentricity. For all three methods the machine was tested at healthy, 25% and 50% static eccentricity levels. The machine was controlled using Field Oriented Control (FOC) using Real Time LABVIEW. Two dimensional (2-D) Finite Element Analysis (FEA) was used to model and simulate the machine under healthy and faulty conditions to evaluate the results from experiments.