Four-quadrant drive control and signal conditioning of DC load motor for permanent magnetic machine testing

The permanent magnetic (PM) synchronous machine testing calls for high performance of the load motor drive control and signal conditioning. The traditional load drive control using motor-alternators cannot meet up with the requirements of the PM machine testing satisfactorily. The paper demonstrates a four-quadrant drive control of the dc load motor using a rectifier apparatus for the PM machine testing. In the proposed approach, the double closed-loop control implements the constant speed and constant torque loads for different testing items. The median filtering and moving average filtering further improve the reliability and accuracy of the testing system. The results have confirmed the correctness and validity of the proposed methods.