Calculation of stator harmonic leakage inductances for multiphase induction motor under open-circuit fault

In order to calculate phase stator harmonic leakage inductances of a multiphase induction motor under open-circuit fault, an analysis method is introduced to determine relationships between phase windings and coils. Firstly, the harmonic leakage inductance between two coils is calculated by subtracting the fundamental inductance from the total inductance, thus obtaining harmonic leakage inductances for any two stator coils. By using graph theory, the incidence matrix between coil branches and one-phase winding loops is established, from which the normalized and unified programming approach is performed to harmonic leakage inductance calculation. Calculated inductances and reactances under different conditions are given. The proposed analysis methods are of versatility and convenience, which is especially suited to calculate stator harmonic leakage inductances of the multiphase induction motor under open-circuit fault.