Sensorless Control of Switched Reluctance Motor Based on Dynamic Thresholds of Phase Inductance

摘要

A new sensorless control scheme for switched reluctance motor drives is presented in this article. This scheme is based on the basic characteristics that the phase inductance changes periodically with the rotor position. First, according to the inductance characteristics, the inductance model can be constructed. Based on the inductance model, the phase inductance at the turn-off angle of the active phase and the turn-on angle of the next phase can be calculated as the two dynamic thresholds. The real inductance is estimated using the terminal measurements of the active phases. By comparing the estimated phase inductance of the active phase with the dynamic thresholds, the drive signals of each phase can be obtained for controlling the switched reluctance motor directly without rotor position information. This sensorless method is quite easy for implementation and possesses good speed-regulating performance. Besides, in order to start the switched reluctance motor from standstill or start those with initial rotor speed conditions without any hesitation, a full-cycle phase inductance subregion method is utilized. Simulation and experimental results are presented and compared for verification.