Research On Sensorless Control Technique Of PMSM Based On High Frequency Square Wave Signal Injection Method

In the field of AC speed control,permanent magnet synchronous motors have the advantages of small size,high reliability,and high operating efficiency.However,in some special occasions,due to the limitation of the position sensor,the sensorless control technology of the PMSM has become a research hotspot.This paper takes the embedded permanent magnet synchronous motor as the research object,and conducts in-depth research on the positionless control technology from the aspects of improving dynamic performance and steady-state accuracy at zero low speed.First,the physical model of the permanent magnet motor is introduced,and the motor is mathematically modeled through coordinate transformation theory.The commonly used vector control strategies are analyzed.The current control strategy and voltage space vector modulation strategy are used to build a double closed-loop of the PMSM.The speed control system verifies the vector control with sensors.In order to study the effect of the low-pass filter on the control system,the current loop and the speed loop are modeled and analyzed.Secondly,the high-frequency model of the permanent magnet synchronous motor is established,and the high-frequency rotating sinusoidal voltage signal injection without position control technology is introduced.From the principle analysis to the estimated rotor position information extraction process.In order to simplify the signal processing process,the positionless control based on high-frequency pulse signal injection is studied.Two schemes are proposed to extract the estimated rotor position under the estimated rotating shaft system and the measured shaft system,and a simulation model is established to verify the feasibility of the scheme.In order to reduce the use of band-pass filters when extracting high-frequency currents,the trajectories of high-frequency response currents are analyzed,and an estimated rotor position extraction scheme based on high-frequency current vector angles is studied to improve the dynamic performance of the control system.In order to reduce the effect of DC bias when extracting high-frequency current,a new type of adaptive filter is designed to effectively suppress the DC bias.Combined with the high-frequency current vector angle rotor position extraction scheme,a simulation model is established and verifie effectiveness of the program.Then,in order to reduce the use of low-pass filters when extracting the estimated rotor position and improve the dynamic performance of the system,the high-frequency square wave injection without position control was studied.Estimate rotor position scheme.A simulation platform was established to verify the effectiveness of the scheme.In order to improve the current utilization rate,a MTPA control strategy based on high-frequency square wave injection was studied.The influence of the control system is analyzed,and the dead-time compensation scheme based on the square wave voltage feed-forward compensation method and adaptive filter voltage feed-forward deadband compensation is researched.Finally,based on the experimental platform,the high-frequency pulse voltage and high-frequency square wave injection were experimentally verified through hardware and software design.This article has 115 pictures,3 tables and 146 references.