A versatile open loop rotor position computation algorithm for the wound rotor induction machine

This paper proposes a simple yet versatile rotor position computation algorithm (RPCA) for the rotor position and speed of a Wound Rotor Induction Machine (WRIM). The rotor position is computed in a straight-forward manner obviating the need for estimation. The resolved components of stator flux vector are computed using measurable stator and rotor quantities. Although it is an open loop technique, it does not involve integration, recursive techniques or programmable low pass filters etc. Starting on the fly, accurate computation near synchronous speed are the other advantages of the algorithm. Reduced complexity and the computational burden facilitate the easy implementation of the algorithm on a low cost fixed point processor. The proposed algorithm (RPCA), is implemented for the laboratory test bench with a 3-hp WRIM system and a TMS320LF2407A DSP controller. The efficacy of the algorithm is demonstrated through the extensive experimental results. Overall, the very encouraging results endorse the proposed algorithm.