Research Of The Sensorless Position Detection Of PMSM

The Permanent Magnet Synchronous Motor (PMSM) is a superiority-performance and widely-used motor. The PMSM speed regulator system. It is widely used in many regions. At present, in mostly regulation drive systems, the mostly method is to install a position sensor in the rotor shaft. But the sensors increase the cost and decrease the reliability. In these backgrounds, there has been an increased interest in developing techniques to obtain the position and speed information for the PMSM without external position sensors. Position sensorless control for PMSM will be widely used in some special or low-precision situation. We can measure the measurable physical quantity such as threephase current, voltage etc to estimate the position and speed through special observer strategy.Firstly, this paper introduced the mathematic model of PMSM, and the vector control theory, expounded the space vector PWM (SVPWM) technology and the theoretical basis of the waveform generation mechanism, then established the sensor position vector control simulation platform of a PMSM.Through the analysis of the sliding mode observation (SMO) and the model reference adaptive System (MRAS), established a corresponding simulation models. Through analysis, found that the two methods are adopted by the mathematical model to extract permanent E.M.F, then calculated the rotor position and speed. Therefore this paper put forward a Permanent E.M.F observation. Directly take the Permanent E.M.F from the model of PMSM to calculate the rotor position and speed So it is simple and transpicuous.By the test with Matlab/Simulink simulation, we analyse the accuracy of estimated rotor position,the impact of the parameters, analyse the sensitivity by parameters of the Permanent E.M.F Observer...