Combined Signal-Injection and Flux-Linkage Approach for Sensorless Control of Switched Reluctance Machines

In this paper a combined position estimation approach for Switched Reluctance Machines (SRMs) using a signalinjection technique and a flux-linkage based method is presented. A second-order Kalman filter is used for smoothing the position as well as for providing the speed; this leads to a considerable reduction of the position error, especially in the vicinity of the speed for which the filter is tuned. The transition between the two estimation methods is controlled via speed-based hysteresis. A 15 kW8/6 SRMis considered; ample simulation and experimental results show the effectiveness of the proposed approach.