A converter-assisting flexible switch topology and its control strategy
FANG Rengcun,
LEI He,
YANG Dongjun,
ZHUANG Kaixun,
ZHA Xiaoming,
SUN Jianjun
Affiliations
FANG Rengcun
Hydrothermal Power Resource Optimization and Simulation Laboratory(State Grid Hubei Electric Power Co., Ltd. Economic and Technical Research Institute), Wuhan 430077, China
LEI He
Hydrothermal Power Resource Optimization and Simulation Laboratory(State Grid Hubei Electric Power Co., Ltd. Economic and Technical Research Institute), Wuhan 430077, China
YANG Dongjun
Hydrothermal Power Resource Optimization and Simulation Laboratory(State Grid Hubei Electric Power Co., Ltd. Economic and Technical Research Institute), Wuhan 430077, China
ZHUANG Kaixun
School of Electrical Engineering and Automation, Wuhan University, Wuhan 430072, China
ZHA Xiaoming
School of Electrical Engineering and Automation, Wuhan University, Wuhan 430072, China
SUN Jianjun
School of Electrical Engineering and Automation, Wuhan University, Wuhan 430072, China
The rapid development of new energy in the distribution network increases its flexibility while making it more complicated to operate and manage the network. For this reason, a novel flexible switch, which is composed of integrated gate- commutated thyristors (IGCT) and parallel voltage converters, is proposed in this paper. Applying virtual synchronous generator (VSG) control on the parallel voltage converterensures smoothness and steadiness while switching from one feeder to another. Firstly, the proposed flexible switch is compared with the flexible multi-state switch and the mechanical switch on their main characteristics. Then, the operating features of the flexible switch before, during, and after feeder fault are analyzed, as well as its switching logic. Finally, the switching process between different feeders is simulated on a control in-the-loop experiment based on RT-Lab. The voltage and current waveforms are obtained under different operating modes and during flexible switching. The experiment resultsshow that the flexible switch has short-term voltage support capability and does not generate voltage and current impulses during the switching process.