摘要
新能源并网逆变器主要用于传输正序有功功率,也用于可补偿配网中广泛存在的无功电流和负序电流。文中提出一种正序优先时的负序电流优化补偿策略,对于一定容量并网逆变器,保持正序功率输出,负序电流优化补偿策略提高了负序电流补偿能力。已知正序功率输出,根据电流约束得到负序补偿电流相量的解域,运用几何思想求出负序电流最优补偿解,并给出生成参考电流的控制框图。文章通过MATLAB分析负序电流优化补偿策略补偿能力提升效果,建立PSCAD仿真,验证所述负序电流优化补偿策略的有效性。结果表明,保持正序功率输出,负序电流优化补偿策略提高了有限容量并网逆变器对负序电流补偿能力。
The grid-connected inverter of new energy is mainly used to transmit active power,and it also could compensate the reactive current and negative sequence current which exists widely in the distribution network.In this paper,a negative sequence current compensation strategy with positive sequence priority is proposed.The negative sequence current optimal compensation strategy improves the compensation capability of negative sequence current while maintaining positive sequence power output for grid-connected inverters with limited capacity.Given the positive sequence output power,this paper obtains the solution domain of the negative sequence compensation current phasor according to the current constraint,the optimal compensation solution is obtained based on the geometric idea,and the control block diagram of generating the reference current is given.This paper analyzes the effect of compensation strategy on the improvement of compensation capability through MATLAB.Finally,PSCAD simulation is established to verify the effectiveness of the negative sequence current optimization compensation strategy.The results show that the negative sequence current optimization compensation strategy improves the compensation capability of negative sequence current while maintaining the positive sequence power output for a grid-connected inverter with limited capacity.
作者
胡长江
魏应冬
陆超
李东东
Hu Changjiang;Wei Yingdong;Lu Chao;Li Dongdong(School of Electrical Engineering,Shanghai University of Electric Power,Shanghai 200090,China;Energy Internet Innovation Institute,Tsinghua University,Beijing 100084,China)
出处
《电测与仪表》
北大核心
2021年第1期109-115,共7页
Electrical Measurement & Instrumentation
基金
国家重点研发计划(2017YFB1200801)
国家电网有限公司科技项目(52020119000N)。
关键词
并网逆变器
容量约束
负序电流补偿
grid-connected inverter
capacity constraint
negative sequence current compensation
