电力系统保护与控制2023，Vol.51Issue(23)：37-44,8.DOI:10.19783/j.cnki.pspc.231007
基于功率自反馈迭代的光伏直流并网系统交流故障有功控制
Active power control strategy for a photovoltaic DC grid-connected system based on power self feedback iteration in an AC fault
摘要
Abstract
After a fault occurs in the AC power grid,the photovoltaic(PV)DC grid-connected system(PV-DCGS)needs to enter the low voltage ride-through(LVRT)mode and reduce the active power of PVs to avoid DC bus overvoltage.However,when the grid voltage drop is deep,the control loop switching of the PVs can cause current backflow,and even damage to the PV panel.Therefore,this paper proposes an AC fault active power control strategy for PV-DCGS based on power self-feedback iteration.Using the PU characteristic curve of PV,an iterative formula of the port voltage reference value is constructed,and the reference value is updated according to the output power feedback of PV.At the same time,the distribution scheme of single-machine maximum utilization is proposed to rationally select the PVs that could participate in the power control task.The advantage of the proposed method is that it does not need to cut off the control loop of the PVs,and it can reliably calculate the port voltage reference value of the PVs.Simulation verification shows that the proposed method can reduce active power in the system and reduce the current fluctuation on the low-voltage side of the DC converter of PV during the PV's mode-switching process,providing a guarantee for the reliable implementation of LVRT in the system.关键词
光伏直流并网系统/交流故障/有功控制/迭代计算/功率自反馈Key words
PV-DCGS/AC fault/active power control/iterative calculation/active power self-feedback引用本文复制引用
李俊涛,贾科,董学正,毕天姝..基于功率自反馈迭代的光伏直流并网系统交流故障有功控制[J].电力系统保护与控制,2023,51(23):37-44,8.基金项目
This work is supported by the National Natural Science Foundation of China(No.52277097).国家自然科学基金项目资助(52277097) （No.52277097）
