Analytical Model of Inductances of Switched Reluctance Machines Considering Slot Leakage Fluxes and Iron Saturations

An analytical model is proposed to predict the inductances of switched reluctance machines (SRMs). The analytical expression of the non-saturated field distribution along the air-gap circumference is derived from the winding function and modulation functions, with which the non-saturated inductances are solved. Moreover, a local magnetic network for stator slots is established to include the leakage inductance, and the model is further enhanced with saturation factors to represent the nonlinear characteristics. The coupling effect between the magnetic saturation and leakage flux is identified to improve the accuracy. The developed model is independent of the experimental data or finite-element method (FEM) results, and it straightforwardly reflects the flux flowing and magnetic field. A variety of validations on SRMs with different slot/pole number combinations, design parameters, and excitations, are conducted based on the FEM. An SRM prototype is manufactured and tested for the experimental verification.