1.Maintenance Company of State Grid Anhui Electric Power Co., Ltd., Hefei 230001, China;2.College of Energy and Electrical Engineering, Hohai University, Nanjing 210098, China;3.China Electric Power Research Institute (Nanjing), Nanjing 210003, China
This work is supported by National Natural Science Foundation of China (No.51777058).
Traditional control strategy of high voltage ride through (HVRT) for photovoltaic (PV) grid-connected inverter (GCI) improves reactive power output at the cost of reducing active power, which is difficult to achieve a balance between grid-side current and DC bus voltage. And it suppresses the transient impact caused by sudden voltage and current changes after the fault removal. Based on the analysis on the transient power characteristics of high voltage, an HVRT control strategy that maintains active power output and adjusts the reference value of reactive current is proposed. Firstly, a small-signal model is used to analyze the transient power characteristics of HVRT, which reveals that the key of suppressing voltage recovery is the constant active power and reactive redundancy on grid side. Secondly, a method for estimating the reference value of reactive current is proposed according to the voltage surge amplitude. On this basis, by combining with active current control, the control capacity of the GCI with three different voltage surge amplitudes is discussed, and the control strategies of HVRT are given respectively. Finally, the simulation and experiments verify the effectiveness of the proposed control strategies.
LI Man,WANG Bing,QU Linan,et al.Control Strategy of High Voltage Ride Through for Adjusting Reactive Current Based on Transient Power Characteristics[J].Automation of Electric Power Systems,2020,44(6):59-66.DOI:10.7500/AEPS20190603011Copy