Research On Sensorless Adaptive Control Of Permanent Magnet Synchronous Motor

Permanent Magnet Synchronous Motor,as a kind of AC synchronous motor,uses a permanent magnet rotor to provide excitation.Compared with traditional electric excitation AC synchronous motor,it has simple structure,small size,light weight,low wear,high efficiency,reliable operation and other advantages.And in the practical application,according to the use of the environment requires flexible design of the shape and size of the motor,which makes permanent magnet synchronous motor has been widely used in CNC machine tools,elevators,new energy vehicles and other areas in people's daily life,industrial and agricultural production and national defense plays an important role.Aiming at the problem of poor reliability and small applicable range of the rotor initial position detection method of the traditional mechanical permanent magnet synchronous motor,a rotor position detection method using high frequency signal injection is proposed.Using the salient pole effect of PMSM,the rotor position information contained in the three-phase current of PMSM is estimated accurately by means of filtering link,heterodyne method and rotor position observer.In the aspect of filtering,a design method of band-pass filter based on proportional resonance controller is proposed,which simplifies the structure of the filter and is easy to realize digitally.The simulation results show that this method can accurately detect the rotor position and the average error of position detection is within 0.1°.In the permanent magnet synchronous motor control system,in order to enable the system to achieve higher performance and stronger stability,it is usually required to obtain accurate rotor position and rotational speed information,which is caused by the installation and use of a traditional mechanical position sensor.For various problems,this paper designs an adaptive control system based on position-free sensing.The system is based on the principle of model Reference adaptive algorithm.The current model of the motor itself is used as the reference model,the current model containing the tunable parameters is used as the adjustable model,and the adaptive estimation of the rotor position of the motor is achieved by Popov super stability theory.This method can accurately estimate the position and speed information of the rotor,and realize the accurate and stable adaptive control of the system.The average error of the speed estimation is within 2%,and the position average error is within 0.1°.