Model correction control strategy for direct drive permanent magnet synchronous motor servo system

Although it has many advantages such as high mechanical rigidity, fast dynamic response and high efficiency, a direct drive permanent magnet synchronous servo motor is sensible to non-linearity, variety of parameter and external disturbance. This paper presents a model correction control strategy, which corrects the unmodeled dynamics of control system and suppresses disturbances by a unique control structure with a state observer based on a Kalman filter and a digital low-pass filter, Theoretical and experimental results indicate that this strategy can effectively eliminate high order dynamic, nonlinearity, measurement noise and variation of load torque in the control system, and improves a direct drive servo control system´s stability, robustness and resistance to disturbances.