Voltage Injection Based Initial Rotor Position Estimation Method for Three-Phase Star-Connected Switched Reluctance Machines

This paper presents a simple method to determine the initial rotor position of a three-phase star- connected switched reluctance machine (SRM) at standstill without position and current sensors. The principle of the initial rotor position estimation is based on the stator inductance variation related to the actual rotor position. In the proposed method, only two narrow voltage pulse injections are applied in sequence. In this method the machine parameters and phase current detection are not required. The method is suitable for low-cost SRM-drive applications. The experimental results were carried out on a 6/4 poles three-phase SRM and show the satisfactory accuracy of the proposed initial rotor position estimation.