Performance comparison of DTC of open-circuit fault PM BLAC motor based on modified voltage and current model flux estimators

Performance of direct torque control (DTC) of three-phase permanent magnet brushless AC (PM BLAC) motor having one phase open-circuit fault (OPOF) is investigated. Modified voltage model flux estimator and current model flux estimator are employed in estimation of stator flux linkages of the motor. The developed torque is then calculated based on the estimated flux linkages. Three-leg inverter is employed in the post-fault operation and a switching table is designed subjected to the topology. Performances of the systems using different flux estimation are compared. Developed torque and stator flux linkages of the faulty motor are regulated and at a constant torque operation stator currents are automatically developed to stabilized the system. Performances of the systems are verified by experimental results.