Online Calculation Method of Hysteresis Limits of a Direct Torque Control for a Switched Reluctance Machine

In this paper an enhanced direct torque control for Switched Reluctance Machines is presented. Due to the heavily nonlinear magnetic characteristic an inherent torque ripple exists. In order to open up new areas of industrial application the torque ripple has to be minimized. The novel strategy includes an online calculation method of the hysteresis limits based on the estimation of the total torque gradient. The adaptive properties of the online calculation method leads to an increased robustness against parameter variation, such as the DC-link voltage. The proposed control strategy is implemented on a field-programmable gate array development platform. Finally simulation as well as experimental results on test bench are carried out to evaluate the control performance.