Research On Sensorless Drive And Control System For PMSM Based On Sliding Mode Observer

With the advanced development of power semiconductor devices, converter topologies, microprocessors, computer-aided design and modern control theory, etc, many kinds of sensorless control methods of PMSM is constantly being improved and can be achieved, because of this, PMSM sensorless drive system is increasingly widespread concerned in variable speed motor control field. In this paper, the actual application of sensorless PMSM which drives the air-condition compressor as research background, sensorless drive and control system of SPMSM based on sliding mode observer as research subject, completed a sensorless drive program which apply to PMSM vector vary frequency system.Firstly, the physical structure of SPMSM is given by describing the rotor design features of SPMSM, and mathematical model of PMSM is established under certain assumptions. Analysis five current vector control methods that formed by different control methods of the combination of d-q current, and make a detailed description of id=0control, determine that current loop of the control system take id=0control method.Secondly, in depth-analysis of the sliding mode variable structure control theory by its history, fundamental principle and elements, and elaborate on the traditional principles of sliding mode observer which uses the deviation between real measurements and estimated values of the motor stator current to continuously correct the observation model to estimate rotor position and speed, some improvement measures are proposed include back EMF filter which based on Kalman filter, improved current observer which introduce saturation function and PLL technology. Through Simulink simulation verify the feasibility and accuracy of the novel sliding mode observer based on above improvements.Finally, on the basis of the simulation, through building up the platform of the hardware system and conducting a series of related experimental studies, for further verification analysis of sensorless PMSM vector control system based on sliding mode observer which is designed in this paper,design control platform that high operational performance DSP TMS320F2808which designed by TI company as the core processor of hardware system, achieved the same results from platform verification and simulation verification, verify the system design is feasible and effective.