Research On Position Control Algorithm For Planar Switched Reluctance Motor

The planar switched reluctance motor(PSRM) has been developed as an attractive candidate for two-dimensional(2D) devices in advanced manufacturing equipments including the semiconductor manufacturing, light manufacturing, and precision machining, etc., owing to its obvious advantages of simple structure, easy manufacture, long stroke, low heat loss, low cost and simple control, etc. However, high-precision motion of the PSRM is restricted due to its highly nonlinear characteristic and large force ripple. Aiming at the issue of the high-precision motion of the PSRM, the position control algorithms of the PSRM are thoroughly researched in this paper. The main research work described as follows.The structure and operation principle of the PSRM are investigated. The mathematic model of the PSRM is built. The PSRM control system and the experimental platform of the PSRM based on dSPACE are developed, respectively. The parameters of the PSRM mathematic model are identified using the least squares method. Based on the identified PSRM mathematic model, the stability, root locus characteristics, frequency domain characteristics, controllability and observability of the PSRM are analyzed, respectively. Additionally, the stability and steady-state error of the PSRM are discussed for the proportional controller, proportional-Derivative controller, proportional-integral controller, and proportional-integral-derivative controller, respectively.Combining the fuzzy control and proportional-derivative(PD) control, a fuzzy PD position controller of the PSRM is designed and then is verified by using MATLAB. The experimental study the PSRM with fuzzy PD position algorithm is carried out for the positioning and dynamic trajectory tracking. Moreover, comparative experiments of the fuzzy PD position control and PD position control are implemented under the same initial parameters of the PD control. The control performances of the fuzzy PD position control and PD position control are comparatively investigated.Aiming at the highly nonlinear characteristic of the PSRM, a sliding mode position controller for the PSRM is proposed and is then verified by utilizing MATLAB. Experiments of the performances of the positioning and dymanic trajectory tracking are carried out for the PSRM with sliding mode control algrithm. The comparative experiments of the sliding mode position controller and PD control are built. Under the same steady-state error, the dynamic performances of the sliding mode position control and PD control are comparatively studied.The experimental results demonstrate that:(1) The steady-state error and dynamic tracking error are respectively ±12.6 ?m and ±41.2 ?m for the PSRM with the fuzzy PD position control.(2) For the PSRM with the sliding mode position control, the steady-state error is ±15.5 ?m, and the dynamic tracking error is ±110.7 ?m.(3) Compared with the PD position control, the proposed fuzzy PD position control and sliding mode control have much less steady-state error and better robustness. The smooth, fast, and accurate positioning and dynamic trajectory tracking of the PSRM is achieved with proposed control algorithms.