Protection Principle for a DC Distribution System with a Resistive Superconductive Fault Current Limiter

Energies

Shimin Xue¹  Feng Gao²  Wenpeng Sun²  Botong Li² 

[1] The Key Laboratory of Smart Grid of Ministry of Education, Tianjin University, Tianjin 300072, China;

关键词: DC distribution system;    relay protection;    resistive superconductive fault current limiter;    transient current;   

DOI  :  10.3390/en8064839

来源: mdpi

【 摘 要 】

A DC distribution system, which is suitable for access to distributed power generation and DC loads, is one of the development directions in power systems. Furthermore, it could greatly improve the energy efficiency and reduce the loss of power transportation. The huge short circuit current is always a great threat to the safety of the components, especially the capacitors and diodes. A resistive superconductive fault current limiter (SFCL), which could respond quickly once a fault happens and limit the fault current to a relatively low level, becomes a good solution to this problem. In this paper, the operational principle of the resistive SFCL is introduced first, and then, the DC short-circuit fault characteristic of the DC distribution system with the SFCL is analyzed and the effectiveness of the SFCL verified. In order to realize the selectivity of the protection in the DC distribution system with SFCL, a new transient current protection principle based on I_p (the peak value of the current) and t_p (the transient time that the current takes to reach its peak value) is proposed. Finally, a model of a 10-kV DC distribution system with an SFCL is established and simulated in PSCAD/METDC. Simulation results have demonstrated the validity of the analysis and protection principle.

【 授权许可】

CC BY   
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