Deadbeat control based on a multipurpose disturbance observer for permanent magnet synchronous motors

Robustness against parameter mismatches and position‐sensorless operation are two important research topics for permanent magnet synchronous motor (PMSM) drives. Usually, the existing observers are designed for achieving a specific function. While here, both the above two functions are integrated into the proposed sliding‐mode disturbance observer: (i) if a position sensor is equipped, accurate current regulation can be achieved by deadbeat predictive current control despite mismatched motor parameters; (ii) if the position sensor is not equipped but with a good estimation of motor parameters, the observer can serve as a back electromotive force estimator. Then, the rotor position can be extracted for position‐sensorless control. Usually, a low‐pass filter is required to suppress high‐frequency noises in the conventional sliding‐mode observer. This inevitably leads to phase delay in the estimation. By comparison, a complex coefficient filter is inherently embedded in the proposed method, which can provide accurate estimation without phase delay or magnitude error. Experimental results obtained from a 2.4 kW PMSM drive platform indicate that high‐performance current control can be achieved with good robustness for position sensor‐based operation. Also, rotor position can be accurately estimated with good steady and dynamic performance for position‐sensorless operation.