Research On Sliding Mode Synchronous Control Of Dual Permanent Magnet Motor System

The permanent magnet synchronous motor has been widely used due to its low cost,high efficiency,and reliable operation.In many industrial occasions,the dual motor is required to operate simultaneously as the source of the driver to meet the power requirements,but the synchronization performance between dual motors is related to production safety,production efficiency,and product quality.Therefore the research of state performance has important engineering value.This article improves the two motor synchronization coordination control performance from the three aspects of improvement of single-motor control performance,determining the dual motor control structure,and designing dual motor synchronization controller.The work content is as follows:(1)This paper describes the characteristics of PMSM rotor structure,establishes the mathematical model of PMSM in synchronous rotating coordinate system based on the method of coordinate transformation,and introduces the principle of vector control and the main content of SVPWM algorithm combined with the mathematical model.(2)Single motor vector control has the two closed-loop feedback links of the current control loop and the speed control loop.The results of modeling and simulation show that the traditional PI control algorithm is insufficient in terms of control accuracy.In order to improve the speed adjusting performance of the single motor,the DPC current prediction algorithm tracking current is introduced in the current control loop;the robust sliding mode speed controller observed by ESO is designed in the speed control loop,which adopts a new reaching law combining exponential reaching law and power reaching law for non-singular fast terminal sliding mode algorithm.The simulation comparison with the PI algorithm verifies that the control method proposed in this paper can reduce chattering and enhance robustness.(3)The principle structure and mathematical model of the master control,the master-slave control,the cross-coupling control are analyzed and their respective control characteristics are obtained.Finally,through the simulation results under the three working conditions of variable speed,starting with load and sudden unbalanced load,the synchronization of cross coupling control mode is better.(4)In order to improve the performance of dual motor synchronization,a power type non-singular fast terminal sliding mode synchronization controller based on the new reaching law was designed to realize the error compensation of the speed of the two motors.In order to verify the performance of the synchronous controller designed in this paper,four other synchronous controllers were introduced for simulation and comparison respectively under load start-up and sudden unbalanced load conditions.The analysis proves that the synchronous controller designed in this paper effectively improves the robust performance,response speed,control accuracy and steady-state characteristics of synchronous operation of dual motors.