Nonlinear position controller design with input-output linearisation technique for an interior permanent magnet synchronous motor control system

A novel, advanced position controller design for an interior permanent magnet synchronous motor control system is proposed. The input-output linearisation technique is used to transfer the system model into a linearised system model. Then, based on the linearised system model, an H_infin controller is designed to achieve robust performance of the position control system. To improve the system performance, a load estimator is used to compensate the external load and the influence of the parameter variations as well. In addition, a maximum torque/ampere control is applied to increase the output torque of the motor. A digital signal processor, TMS 320LF2407, is used to execute the speed-loop and position-loop control algorithms. As a result, the hardware circuit is quite simple. Several experimental results show that the proposed system has fast transient responses, good load disturbance rejection responses and good tracking responses.