1. State Grid Tianjin Jizhou Electric Power Supply Company, Tianjin 301900; 2. School of Energy and Power Engineering Nanjing University of Science and Technology, Nanjing 210094
Abstract:Scenario of Passive grid connecting two VSC-HVDC transmission systems has been investigated in this paper. A control method with hierarchy is proposed. VSCs have been grouped based on a hierarchy of various categories. Distance which denotes the number of electrical connections between strong grid and VSC station is used to define the hierarchy used in this paper. Different control methods are used in different categories to regulate different variables. This method can be used in DC grids with many VSCs grouped into a hierarchy of various categories. This paper presents a multilayer DC system with a passive AC grid inside the DC grid. The control principle of VSCs connected with the passive grid is investigated. The AC voltage control and active power control is assigned to different VSC based on its power flow in the inner passive AC grid. Also a DC voltage control is integrated in the hierarchy control system to improve the dynamic instability.
于永生, 冯延晖, 邱颖宁, 贾建华, 肖建超. 含有弱交流电网的电压源换流站直流电网分级控制策略研究[J]. 电气技术, 2019, 20(3): 42-49.
Yu Yongsheng, Feng Yanhui, Qiu Yingning, Jia Jianhua, Xiao Jianchao. Research on control method of voltage source converter based DC grid with weak AC system integrated. Electrical Engineering, 2019, 20(3): 42-49.