Sensorless Control Strategy for Interior Permanent Magnet Synchronous Motor Based on ADRC and Differential of Active Flux

A control strategy for constructing current active disturbance rejection controller based on α and β axial current as the main variable of the extended state observer is presented, to realize the high performance control of the interior permanent magnet synchronous motor without position sensor. In the two-phase stationary coordinate system, the current active disturbance rejection controller takes currents as input, voltages which drive motor by an inverter as output directly, so the accumulated error caused by the application of the rotor position angle in multiple coordinate transformations is eliminated, thus improving the control accuracy of the system apparently. Also, through the expansion state observer in the current active disturbance rejection controller, the differential of active flux containing the rotor position information is observed and compensated as the unknown perturbation, and taken as input to the phase-locked loop; therefor, the accurate speed and the rotor position angle are obtained, and the high precision control of the motor is realized. The simulation results show that the method has such advantages as high control precision, strong anti-interference ability.