Research On Sensorless Control System Of The Low Speed And High Torque PMSM

This paper select the typical application example in the low speed and high torque drive system—gearless elevator traction machine drive system. On the background of this system, the low speed and high torque PMSM was took as the research object, this paper has researched and accomplished the sensorless vector control of the low-speed and high-torque PMSM. The control system is supplied with spatial vector pulse width modifying (SVPWM) inverter can directly drive elevator without decelerator. This direct drive of elevator has not only simplified the construction of transmission mechanism which improved transmit power density and efficiency of the drive system, but also increased precision and reliability of the control system.Firstly, the sensing method of the rotor position of PMSM is analyzed in detail. After that, an estimated method based on SMO is designed which has a strong robustness, simple control algorithm and easy, implementation of engineering application.Secondly, on the basis of analyzing the mathematical model and vector control principle of PMSM, the system model of the sensorless control of PMSM based on SMO is established, which provides a theoretical basis for carrying out simulation and experiment. This paper uses the simulation software MATLAB/Simulink to simulate the drive system of low speed and high torque PMSM and the results show that the system models are rightly built and control strategy is feasible.Finally, this paper choose TMS320LF2407 as the controller and composes the complete control software using assembly language, it realizes stator phrase current sampling, rotor speed/position observation and output of drive signal. On the design experimental platform, the sensorless control strategy was research. The result indicated the system performance meets the design requirements.