A novel on-line MRAS rotor resistance identification method insensitive to stator resistance for vector control systems of induction machines

On-line identification and correction of the rotor resistance is essential for improving the static and the dynamic performances of the vector control systems of induction machines. In this paper, a novel MRAS algorithm on-line identifying the rotor resistance, which is completely free from the effects of the stator resistance, is developed. Both the reference model and the adjustable model do not include the stator resistance R_s items. Therefore, the usefulness of the proposed MRAS algorithm is enhanced. Simulation results and experimental results are given to verify the effectiveness and the validity of the proposed MRAS identifier. The impact of the variations of the frequency reference, the load torque and the other motor parameters including the stator resistance on the estimation performance of the rotor resistance is analyzed.