Mechanism of the control coupling and suppression strategy using PI and repetitive control in grid-connected inverters

作者：Zhang, Xing; Wang, Yangjun; Yu, Changzhou; Qiao, Caixia; Zhou, Yanfeng; Ni, Hua

来源：Proceedings of the CSEE, 2014, 34(30): 5287-5295.

DOI：10.13334/j.0258-8013.pcsee.2014.30.004

• Grid connected inverters
• Improved repetitive controls
• Proportional integral
• Repetitive control
• Steady state accuracy
• Steady state control accuracy
• Zero phase error tracking control
• Zero phase error tracking controls (ZPETC)

For grid-connected inverter systems, the repetitive control is often adopted to suppress the grid current harmonics and improve the steady-state control accuracy. Dynamic performances of the single repetitive control are poor, and the proportional integral (PI) and repetitive control is widely used due to its fast dynamic process and high steady-state accuracy. However, there exists control coupling between two regulators, which causes distortion of grid currents when the system is in the dynamic process. The mechanism of control coupling was analyzed and a control strategy based on an improved repetitive control for grid-connected inverters was proposed in this paper. The improved repetitive control based on the zero phase error tracking control (ZPETC) can improve the dynamic performance of the system;while a dynamic delay process for the input signal can solve the control coupling problem. Finally, simulation and experiment results show that the theoretical analysis is correct and the proposed control scheme is effective.

• 出版日期2014
• 单位合肥工业大学