Hall-effect sensor fault detection, identification an compensation in brushless DC drives

This paper investigates Hall-effect sensor faults in brushless dc drives and proposes a very effective methodology for their detection, identification and compensation. It is shown that these faults cause erroneous commutation, generally leading to unstable operation. By using a fault detection and identification technique proposed by the authors in a previous paper related to low cost field-oriented drives, [22], together with appropriate fault-compensated position and speed estimation algorithms, it is shown for the first time that proper operation is guaranteed for both single and double faults. Comparative experimental results are provided for operation with three state of the art, Hall-effect sensor based, estimation algorithms: the zeroth order algorithm, [19], the hybrid observer, [20], and the vector-tracking observer, [21]. It is verified that stable operation is achieved with three, two or only a single Hall-effect sensor functioning correctly.