Current-Scaling Gain Compensation of Motor Drives Under Locked-Rotor Condition Considering Inequality of Phase Resistances

This article proposes a current-scaling gain-compensation algorithm for motor drive applications under the locked-rotor condition. In heavy industrial applications, such as elevators and cranes, initial commissioning tests are performed with the rotor locked. To compensate for errors in the current-scaling gain, the proposed method controls the current in the d-q axis using two-phase current-sensing methods in a stationary reference frame. The three-phase scaling gains are then estimated using the resulting d-axis current command and output voltage and are compensated for using these estimations. The proposed method delivers accurate compensations by considering the inequality between phase resistances. The effectiveness of the proposed algorithm is verified through simulations and experiments.