Study of high order differential feedback control of DC-link voltage in active power filter

This paper presents the principle and configuration of HODFC and its theory can be applied in the control of DC-link Voltage in parallel active power filter (APF). By constructing a high-order differentiator, we extracted some signals related to a given signal, such as its first and second order differential signal and the output signal. By using high-adaptive differential feedback control law, the amplitude of the active current in the power system can be obtained. The proposed control scheme simplifies the control process and reduces the detecting sensors. It was also demonstrated that this proposed control strategy provides with feasibility, strong adaptability and robustness by numerical simulations.