Abstract: A sixphase tenpole faulttolerant permanent magnet motor(FTPMM) is taken as an example to obtain the chief components of its winding self inductance, such as the magnetizing inductance, harmonic leakage inductance, slot opening leakage inductance and slot inner leakage inductance, by analyzing the distribution of magnetic flux; and large inductance is found to be realized by increasing the leakage of slots and harmonicsIn order to improve the validity of the optimization in motor design, a new magnetic circuit model and arithmetics are put forward, then a high accuracy nonlinear analysis formulation of winding self inductance and its portions are obtained by introducing two parameters: the calculation thickness and the magnetic force of slot openingThe largest error of self inductance calculated by the analysis method is below 13% as compared with the verification results of finite element method(FEM) and experiments, which shows that the motor possesses strong fault toleranceTherefore, the analytical formulation provides a theoretical reference for faulttolerant motor optimization design and performance analysis.

Key words: fault tolerant permanent magnet machine, slot leakage inductance, magnetic circuit model, optimization design, high accuracy and nonlinear winding, analytical formulation of winding self inductance