Stability Analysis And Coordinating Control Of Two Coupling Permanent Magnet Synchronous Motors System

Abstract:Coupling multi-motors system is widely used in many fields such as military, aviation, and transportation. Research on the stability analysis and coordinating control strategy of coupling multi-motors system is of great theoretical significance and practical value to improve system’s performance and ensure system’s stable operation. According to the actual conditions of engineering, multi-motors system can be divided into two parts, i.e., multi-motor system with certain coupling relationship and multi-motor system with uncertain coupling relationship. Two coupling motors system is one of the most widely used multi-motors system in engineering, and owing to its advantages like low loss, high efficiency, and high torque-to-current ratio, permanent magnet synchronous motors (PMSMs) have replaced the traditional motors in many fields. The research objects of this paper are multi-motors systems with certain coupling relationship and multi-motors systems with uncertain coupling relationship. The main works of this paper are presented as follows.1. As for the two coupling PMSMs system with certain coupling relationship, first of all, the mathematical model of the system is established by combining the state equation, motion equation of motor with coupling relationship model. The robust stability of system is analyzed, and in terms of bilinear matrix inequations, sufficient conditions for the robust coordinating stability of the system are derived. A robust coordinating synchronization controller is designed via cross-coupling idea and PI control idea. The proposed controller can deal with load uncertainty without load observer, and has robustness for the environment disturbance and parameter perturbation, and it is very simple and is easy-to-use in engineering. Finally, the Simulink simulation model of the system is constructed, and the effectiveness of the proposed control strategies is verified by Simulink simulation carried out via Matlab/Simulink soft.2. As to the two coupling PMSMs system with uncertain coupling relationship, the mathematical model of the system is constructed by combining the dynamical mathematical model of PMSM with uncertain coupling relationship model. Next, a synchronization coordinating controller based on load observer is developed through feedforward control idea. Finally, the Simulink simulation model of the system is constructed, and the effectiveness of the proposed control strategies is verified by Simulink simulation carried out via Matlab/Simulink soft. The simulation results reflect that the proposed load observer can accurate observe the load information, and the proposed control strategies have better coordinating performance and tracking performance than that of traditional PI controller.