Research On Current Predictive Control And Position Sensorless Technology Of Dual Three-phase Permanent Magnet Synchronous Motor

In recent years,permanent magnet synchronous motors（PMSM）have been widely used in aerospace,military ships and equipment manufacturing industries.The industry’s requirements for motor control systems tend to increase in response speed,power density,and reliability.This makes the traditional three-phase motor often unable to meet the application requirements,and the multi-phase motor has the advantages of low-voltage,high-power output,smaller torque fluctuation and stronger fault-tolerant control capability due to the larger number of phases,and has received extensive attention.In traditional vector control,due to the delay of the current loop under PI control,the dynamic response of the system will be reduced.In addition,traditional vector control uses a position sensor to obtain the rotor position signal,which increases the volume of the system and points of failure.To this end,this dissertation proposes a deadbeat current predictive control algorithm with delay compensation to replace the traditional control,and proposes a new sliding mode observer to estimate the rotor position.The main research contents of this dissertation are as follows:In this dassertation,the mathematical model of dual-phase PMSM in static coordinate system is established first,and the dual dq transformation and vector space decoupling（VSD）transformation matrix of dual three-phase PMSM is derived.At the same time,the four-vector and two-vector modulation algorithm principles of multi-phase motors are analyzed,and the vector control strategy based on id=0 is introduced.In view of the delay problem in the PI control current loop,the cause and effect are analyzed,and a deadbeat current control algorithm with delay compensation is proposed.This method uses multi-step prediction of voltage and current to The delay in the current loop is compensated.The position sensorless detection technology of dual three-phase PMSM has been deeply studied.Aiming at the phase delay and chattering problems of traditional sliding mode observers,a new sliding mode observer algorithm is proposed.The observer is composed of a nonlinear expansion observer and an improved sliding mode observer.The nonlinear expansion observer is used to observe the back EMF,the observed back EMF difference is used to construct the sliding mode surface,and the sliding mode observer is designed to observe the rotor position.The MATLAB/Simulink simulation was built to verify the proposed algorithm.The simulation results show that the improved deadbeat algorithm can greatly improve the dynamic performance of the system.The new position sensorless detection algorithm has strong robustness and can significantly improve the dynamic response and anti-disturbance performance of the system.The system design is completed,the experimental platform is built and the experimental research is carried out.The results verify the correctness and feasibility of the algorithm proposed in this dissertation.