| With the development and progress of the times,the body design and control methods of modern motors are becoming more and more mature.Compared with the three-phase permanent magnet synchronous motor（PMSM）control system,the dual three-phase PMSM control system has multiple degrees of freedom control,high power capacity,and high reliability.It is widely used in aircraft,ships,automobiles and other occasions that require high reliability.The weakest link in the dual three-phase PMSM control system is the power switch and position sensor.They are damaged at a higher frequency.Therefore,in this dissertation,the vector control technology,fault-tolerant method and position sensorless detection technology of dual three-phase PMSM are studied for the above two problems.First,the control technology of dual three-phase PMSM in normal mode is studied,the mathematical model of the motor in the natural coordinate system is established,and the vector space decoupling（VSD）transformation is carried out to simplify the motor model according to the winding distribution and the magnetic potential relationship,using id=0 vector control technology,and through the largest four vector modulation method to improve the bus voltage utilization.Then the fault-tolerant control technology in the case of phase failure is studied,and the deficiencies of the mathematical model of the reduced-dimensional motor are analyzed.The need for multiple decoupling transformations increases the control difficulty.Adopt current hysteresis fault-tolerant control based on normal decoupling transformation with optimal function as the optimization objective,and this method is relatively simple and easy to follow-up applications.Secondly,aiming at the shortcomings of traditional sliding mode observer（SMO）and arctangent function in estimating rotor position and improving it,a new dual three-phase PMSM sliding mode sensorless control technology and rotor position estimation method are proposed.The introduction of the stator current frequency variable tracker（FVT）on the basis of the traditional SMO solves the problem of dynamic estimation of the back electromotive force（BEMF）and reduces the high-frequency chattering caused by dynamic sliding mode switching.At the same time,in order to improve the estimation accuracy of the rotor position and the ability to resist load disturbance,a third-order extended state observer（ESO）was constructed to estimate the rotor position information.Finally,based on the theoretical research,a simulation platform of the motor system is constructed,which preliminarily verifies the correctness of the theoretical research.Then the motor control system design and hardware platform construction were carried out,and the feasibility of applying the improved SMO based on ESO to estimate the rotor position in the normal mode and fault-tolerant control of dual three-phase PMSM was verified through experimental research. |
