Research On Energy Feeding Control Of Four-quadrant Converter Of Permanent Magnet Synchronous Motor

When the permanent magnet synchronous motor is running in the power generation condition,the regenerative energy generated by the motor will cause the DC bus voltage to be pumped.If the pumping voltage is too high,it will affect the stability and safety of the operating system.This thesis takes the four-quadrant converter as the research object,aiming at stabilizing the DC side voltage and optimizing the power quality when the regenerative energy is connected to the grid.The main research contents are as follows:First,introduce the research background and significance of the permanent magnet synchronous motor regenerative energy feed system,the development of energy processing system and the development status of the four-quadrant converter at home and abroad,and introduce the key technical issues required for the normal operation of the regenerative energy feed system.Secondly,the permanent magnet synchronous motor adopts the vector control method,in order to simulate the actual operation of the motor under complex conditions,a simulation platform for the permanent magnet synchronous motor towing is established.According to the working principle of the four-quadrant converter,its characteristics are analyzed,and the mathematical model is established in the two-phase rotating dq coordinate system,and the voltage loop,current loop parameters and grid-side inductance parameters of the four-quadrant converter are designed.Then,the permanent magnet synchronous motor paired towed simulation platform and the four-quadrant converter are combined to form a permanent magnet synchronous motor regenerative energy feed system.Thirdly,analyze the principle of regenerative energy feedback of the permanent magnet synchronous motor energy feed system,and establish a mathematical model of the DC side voltage;for the slow response speed of the four-quadrant converter system,which leads to the problem of large DC side voltage fluctuations,nonlinear current observation feedforward is adopted The compensation scheme improves the response performance of the system and quickly feeds the regenerative energy back to the grid.Finally,in response to the real-time change of the regenerative energy feedback power during the change of the motor speed,the four-quadrant converter has obvious grid-connected hysteresis;the fuzzy PI current controller is designed,and the PI controller parameters are dynamically adjusted in real time to reduce the The purpose of grid current harmonics.In view of the low regenerative power grid connection,the grid-side current harmonics cannot meet the grid-connected requirements and the inverter grid-connected power exceeds the limit and fault conditions;according to the actual requirements of the project,the inverter grid-connected protection device is adopted,and the comprehensive system is regenerated energy efficiency Perform analysis.