Improvement of low speed operation of electric machine with an inertia identification using ROELO

A new scheme to estimate the moment of inertia in the motor drive system in very low speed is proposed. The simple speed estimation scheme, which is used in most servo systems for low-speed operation, is sensitivity to variations in machine parameters especially the moment of inertia. To estimate the motor inertia value, a reduced-order extended Luenberger observer (ROELO) is applied. The effectiveness of the proposed ROELO is verified by simulation and experiment.