School of Electric Power, South China University of Technology, Guangzhou 510640, China
This work is supported by National Natural Science Foundation of China (No. 51777078).
Microgrid is a nonlinear and strong coupling system with multiple constraints and large load disturbance. The conventional proportional-integral (PI) dual-loop control has been unable to meet requirements. The active disturbance rejection control (ADRC) technology can significantly improve the performance of microgrid inverter control system by compensating the disturbances. This paper proposes a time-frequency voltage control strategy of microgrid inverter based on linear active disturbance rejection control (LADRC). In order to improve anti-disturbance and dynamic performances of microgrid inverter, the decoupling of dq axis, the dimension-reduced extend state observer (ESO) with capacitive current and the linear state error feedback control law are designed and analyzed in the time domain. In order to improve the tracking accuracy and anti-disturbance performance of microgrid inverter at various harmonic frequencies, the frequency response characteristics of time-domain LADRC system are analyzed. Based on it, the real and imaginary decoupling links and the time-frequency domain LADRC strategy are designed and analyzed. Finally, the proposed strategy is verified by experiments for the microgrid inverter operating in the island mode. Experimental results show that the time-frequency voltage control strategy of microgrid inverter based on LADRC has better decoupling, anti-disturbance and dynamic performance when it is compared with PI double-loop control. Moreover, it can accurately control harmonic voltage to achieve harmonic suppression.
LI Zhihua,ZENG Jiang,HUANG Junchi,et al.Time-Frequency Voltage Control Strategy of Microgrid Inverter Based on Linear Active Disturbance Rejection Control[J].Automation of Electric Power Systems,2020,44(10):145-154.DOI:10.7500/AEPS20190824003Copy