Discrete state-space voltage controller for voltage source inverters with LC filter based on direct pole-zero placement design

摘要

State-space control provides both high dynamic performance and sufficient stability margin to voltage source inverters with LC filter. In this paper, discrete state-space voltage controller is proposed by using direct pole-zero placement in rotating reference frame. Based on the discrete-time system model, the state feedback control with the reference feedforward path is designed in consideration of the digital delay. The output current decoupling is incorporated to suppress the effect of the output current disturbance. The controller gains are derived as the functions of the system parameters and design specifications. Additionally, the guideline about pole-zero assignment is presented to improve the performance and stability of the proposed controller. The effectiveness of the proposed controller is verified with experimental results.