Characterization of nonlinearaity using simplified modell for the electromagnetic behaviours of switched reluctance motors

An analytical nonlinear model to describe the electromagnetic characteristics in switched reluctance motors (SRM) is proposed. The model is based on the piecewise linear and the least square (LS) method. The analytical nonlinear model is a two-dimensional fifth-order polynomial function of the SRM current and the rotor position, and the coefficients in the polynomials are determined by the LS method. In addition, the analytical expression of the instantaneous torque is derived from the proposed model of the electromagnetic characteristics. The torque expression is a two-dimensional fourth-order polynomial function of the SRM current and the rotor position. The simulation and experimental results under the single-pulse and the current hysteresis controls were used to validate the proposed model. This model is suitable for rapid prediction of performances of the SRM and real-time control.