Improved Linear Active Disturbance Rejection Controller Control Considering Bus Voltage Filtering in Permanent Magnet Synchronous Generator

In the permanent magnet direct drive wind power generation system, the direct current (DC) bus voltage signal of the converter is usually used as the feedback of the voltage outer loop. Because of the existence of random white noise and the measurement error when the sensor collects the DC bus voltage signal, it is necessary to filter the bus voltage signal through the first-order inertial link. The time constant of the first order inertial link is usually 10ms-15ms. In the traditional voltage external loop second-order active disturbance rejection controller (ADRC) system, the influence of the bus voltage filter is not considered in the design of ADRC, which results in the phase lag and amplitude offset between the feedback of the controller and the real bus voltage. This will make the performance of the system affected by the time constant of the first-order inertial link. In this paper, an improved ADRC considering the bus voltage filter is proposed. The filtered bus voltage is expanded into a new state variable. The voltage before the filter is estimated by using the fourth-order linear expansion state observer (LESO) and used as the feedback. The simulation results show that the improved ADRC system has better control performance.