摘要
高压柔性直流电网作为解决可再生能源大规模接入和消纳问题的有效手段,已成为未来电力系统的重要发展方向之一,但也使其潮流控制和故障保护的问题更加突出。为了克服以上问题、提高系统稳定性,提出了一种具备直流潮流控制与故障限流双重功能的电感耦合型复合装置。首先,提出了该复合装置的拓扑结构,该拓扑在传统直流潮流控制器基础上增加了可共用耦合电感的限流支路;其次,详细分析了直流潮流功能的工作原理、理论推导及其控制策略;然后,基于故障条件下提出的限流动作时序,进一步解析了稳态、限流、故障切除和泄能4个不同时段下耦合电感的作用效果,并研究了各时段直流故障电流的计算;最后,在MATLAB/SIMULINK仿真软件上搭建四端直流电网模型,仿真结果表明所提拓扑通过共用耦合电感实现了良好的潮流控制和抑制短路电流的功能,在短路故障状态下缩短故障电流的切除时间,在保证经济性的同时提高了系统的稳定性。
As an effective means to solve the problem of large-scale access and consumption of renewable energy,the high-voltage flexible DC grid has become one of the important development directions of the future power system,but it also makes the problems of power flow control and fault protection more prominent.In order to overcome the above problems and improve the stability of the system,this paper proposes an inductively coupled composite device with dual functions of DC power flow control and fault current limiting.First,the topology of the composite device is proposed;This topology adds a current-limiting branch that can share coupled inductors on the basis of the traditional DC power flow controller.Secondly,the working principle,theoretical derivation and control strategy of the DC power flow function are analyzed in detail.Thirdly,based on the current limiting action sequence proposed under fault conditions,four different periods of steady state,current limiting,fault removal and energy discharge are further analyzed.The effect of coupling inductance and the calculation of DC fault current in various periods are studied.Finally,a four-terminal DC power grid model is built on MATLAB/SIMULINK simulation software.The simulation results show that the proposed topology achieves good power flow control and short-circuit current suppression by sharing coupled inductors,and shortens the fault current removal time under short-circuit fault conditions.Therefore,the stability of the system is improved while ensuring economy.
作者
王鹤
许家豪
边竞
沈冠冶
WANG He;XU Jiahao;BIAN Jing;SHEN Guanye(Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology,Ministry of Education(Northeast Electric Power University),Jilin 132012,China;Changchun Power Supply Company of State Grid Jilin Electric Power Co.,Ltd.,Changchun 130000,China)
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2023年第5期1985-1996,共12页
High Voltage Engineering
基金
国家自然科学基金(U2066208,52177074)
东北电力大学博士科研启动基金(BSJXM-2021204)。
关键词
VSC-HVDC
潮流控制
故障限流
耦合电感
复合装置
VSC-HVDC
power flow control
fault current limiting
coupling inductance
composite device
