Linear flux-switching permanent magnet motors(LFSPMs) have been proposed for long stator applications such as rail transit. However, the conventional linear permanent magnet synchronous motor(LPMSM) suffers from thrus...Linear flux-switching permanent magnet motors(LFSPMs) have been proposed for long stator applications such as rail transit. However, the conventional linear permanent magnet synchronous motor(LPMSM) suffers from thrust ripple, which degrades the motor performance. The thrust ripple in LFSPMs is mainly caused by detent force and asymmetric electromagnetic parameters, excluding external disturbances. Moreover, the 12/13 slot-pole LFSPM exhibits unique inductance characteristics, which lead to different effects on thrust ripple. First, the detent force in the LFSPM is analyzed through finite element method(FEM). In addition, new finite element(FE) models are proposed for further analysis of the cogging force in LFSPMs. Second, the unique inductance characteristics of the 12/13 slot-pole LFSPM are investigated, and then the thrust ripple caused by asymmetric electromagnetic parameters is calculated by the virtual displacement method. Third, the mathematical model considering the thrust ripple is established for the LFSPM, which provides a foundation for subsequent research on thrust ripple suppression control strategies. Finally, the thrust ripple analysis is validated by comparing FEM results, modeling simulations, and experimental data.展开更多
In this paper,a compound sliding mode velocity control scheme with a new exponential reaching law(NERL)with thrust ripple observation strategy is proposed to obtain a high performance velocity loop of the linear perma...In this paper,a compound sliding mode velocity control scheme with a new exponential reaching law(NERL)with thrust ripple observation strategy is proposed to obtain a high performance velocity loop of the linear permanent magnet synchronous motor(LPMSM)control system.A sliding mode velocity controller based on NERL is firstly discussed to restrain chattering of the conventional exponential reaching law(CERL).Furthermore,the unavoidable thrust ripple caused by the special structure of linear motor will bring about velocity fluctuation and reduced control performance.Thus,a thrust ripple compensation strategy on the basis of extend Kalman filter(EKF)theory is proposed.The estimated thrust ripple will be introduced into the sliding mode velocity controller to optimize the control accuracy and robustness.The effectiveness of the proposal is validated with experimental results.展开更多
Direct-drive actuators,linear motors are widely used in many industrial and military applications,particularly in high-end manufacturing due to advantages of high force density,rapid dynamic response,and low thermal l...Direct-drive actuators,linear motors are widely used in many industrial and military applications,particularly in high-end manufacturing due to advantages of high force density,rapid dynamic response,and low thermal losses.Permanent magnet linear synchronous motors(PMLSMs)can dramatically improve the dynamic and static performance of the motion system.However,as one of the most critical sources of error,the thrust ripple of linear motors can deteriorate performance and even excite the mechanical resonance.Thrust ripple suppression technology had received broad interest and has been researched extensively.Therefore,this paper summarizes different types of thrust ripple suppression methods and their principles are analyzed in detail.Firstly,structural optimization methods are introduced to suppress the thrust ripple and increase the precision of the thrust.Secondly,control methods are described to decrease the velocity fluctuation caused by the thrust ripple.Thirdly,a combination of structural design and control method is presented to compensate the ripple,meaning high order harmonic components are eliminated by permanent magnets(PM)skewing technology and low order harmonic are compensated by a linearization observer.Finally,conclusions are made regarding thrust ripple suppression technology and the future trend is proposed.展开更多
基金partly supported by the CAS Project for Young Scientists in Basic Research under Grant YSBR-045the National Natural Science Foundation of China under Grant 52307071。
文摘Linear flux-switching permanent magnet motors(LFSPMs) have been proposed for long stator applications such as rail transit. However, the conventional linear permanent magnet synchronous motor(LPMSM) suffers from thrust ripple, which degrades the motor performance. The thrust ripple in LFSPMs is mainly caused by detent force and asymmetric electromagnetic parameters, excluding external disturbances. Moreover, the 12/13 slot-pole LFSPM exhibits unique inductance characteristics, which lead to different effects on thrust ripple. First, the detent force in the LFSPM is analyzed through finite element method(FEM). In addition, new finite element(FE) models are proposed for further analysis of the cogging force in LFSPMs. Second, the unique inductance characteristics of the 12/13 slot-pole LFSPM are investigated, and then the thrust ripple caused by asymmetric electromagnetic parameters is calculated by the virtual displacement method. Third, the mathematical model considering the thrust ripple is established for the LFSPM, which provides a foundation for subsequent research on thrust ripple suppression control strategies. Finally, the thrust ripple analysis is validated by comparing FEM results, modeling simulations, and experimental data.
基金supported in part by National Natural Science Foundation of China(52177194)in part by State Key Laboratory of Large Electric Drive System and Equipment Technology(SKLLDJ012016006)+1 种基金in part by Key Research and Development Project of ShaanXi Province(2019GY-060)in part by Key Laboratory of Industrial Automation in ShaanXi Province(SLGPT2019KF01-12)(。
文摘In this paper,a compound sliding mode velocity control scheme with a new exponential reaching law(NERL)with thrust ripple observation strategy is proposed to obtain a high performance velocity loop of the linear permanent magnet synchronous motor(LPMSM)control system.A sliding mode velocity controller based on NERL is firstly discussed to restrain chattering of the conventional exponential reaching law(CERL).Furthermore,the unavoidable thrust ripple caused by the special structure of linear motor will bring about velocity fluctuation and reduced control performance.Thus,a thrust ripple compensation strategy on the basis of extend Kalman filter(EKF)theory is proposed.The estimated thrust ripple will be introduced into the sliding mode velocity controller to optimize the control accuracy and robustness.The effectiveness of the proposal is validated with experimental results.
基金the State Key Program of National Natural Science of China(51537002)the National Natural Science Foundation of China(51177024)the Natural Science Foundation for Distinguished Young Scholars of China(51225702).
文摘Direct-drive actuators,linear motors are widely used in many industrial and military applications,particularly in high-end manufacturing due to advantages of high force density,rapid dynamic response,and low thermal losses.Permanent magnet linear synchronous motors(PMLSMs)can dramatically improve the dynamic and static performance of the motion system.However,as one of the most critical sources of error,the thrust ripple of linear motors can deteriorate performance and even excite the mechanical resonance.Thrust ripple suppression technology had received broad interest and has been researched extensively.Therefore,this paper summarizes different types of thrust ripple suppression methods and their principles are analyzed in detail.Firstly,structural optimization methods are introduced to suppress the thrust ripple and increase the precision of the thrust.Secondly,control methods are described to decrease the velocity fluctuation caused by the thrust ripple.Thirdly,a combination of structural design and control method is presented to compensate the ripple,meaning high order harmonic components are eliminated by permanent magnets(PM)skewing technology and low order harmonic are compensated by a linearization observer.Finally,conclusions are made regarding thrust ripple suppression technology and the future trend is proposed.
