| Permanent magnetic linear synchronous motor (PMLSM) has the advantages of higher speed, higher precision and faster response compared to other types of linear motor, and is a kind of dominant direct-drive motor, having broad prospect in the fields of CNC system, robotics, and semiconductor processing equipments. Active disturbance rejection control (ADRC) is a new kind of practical control technology, which adopts nonlinear processing methods. ADRC observes and compensates external action affecting dynamic characteristics of controlled plant, which is recognized as "disturbance", and achieves "ADRC" using efficient nonlinear states error feedback control. Therefore, ADRC is a kind of better and more efficiency control technology with strong robustness and engineering practicality.In this paper, friction and detent force of PMLSM are analyzed, and their models are built by means of finite element method and detent force test experiment. Based on the above research, PMLSM's mathematical model is built with multiple disturbing forces, and the corresponding simulation model of PMLSM is also built in the MATLAB/Simulink.Because measurement noise of system output is present in actual system, improvement is made for traditional ADRC algorithm and an improved ADRC is proposed. Tracking differentiator with differential prediction and compensation is added in the feedback channel of traditional ADRC, which is used to filter out measurement noise, calculate each order differential signal of system output, and gives states of controlled plant instead of extended state observer (ESO). Current ADRC decoupling controllers of d-q axes are given, which adopt improved ADRC algorithm, based on analysis of coupling perturbation of states equation of d-q axis currents. The current ADRC controller observes and compensates coupling perturbation, which is recognized as "disturbance" to current dynamic equation, and realizes current ADRC decoupling control finally. Simulation results show that the improved ADRC can achieve better performance than traditional ADRC and PID.Multiple disturbing forces directly affect the speed stability and position accuracy of PMLSM. This paper utilizes improved ADRC algorithm to observe and compensate the disturbance on PMLSM caused by multiple disturbing forces. First-order speed ADRC is given firstly, but there exists some drawback. Further second-order speed ADRC is imposed by analyzing second-order motion equation in order to overcome the disadvantage of first-order speed ADRC, and simulation experiments show that second-order speed ADRC has better performance. Then position ADRC is given in order to overcome the disturbance on position dynamic characteristics caused by multiple disturbing forces. Block diagrams of all ADRC controllers and control systems are illustrated in this paper, and their simulation model are built in MATLAB/Simulink. Simulation experiments are done to verify these ADRC control system.This paper implements semi-physical tests of PMLSM second-order speed ADRC control system using model-based design methodology, including rapid prototyping (RP) system test, software in the loop (SIL) test and hardware in the loop (HIL) test. In this way, the second-order speed ADRC algorithm and generated C codes have been tested and validated before real controller hardware is carried out. Then the PMLSM ADRC control system experimental platform is carried out by designing and realizing system hardware and software, in which the digital signal processor (DSP) and Field Programmable Gate Array (FPGA) are the core processors. Experiments of PMLSM current, speed and position ADRC control systems are done on this experimental platform, which apply improved ADRC control algorithm proposed in this paper. Experiments results indicate that the PMLSM control system adopting improved ADRC control obtains more dynamic-static performance and ability of disturbance rejection than PID control and traditional ADRC control.
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