Differential protection strategy for distribution network based on 5G communication

• Published in: IET generation, transmission & distribution transmission & distribution, 2023-05, Vol.17 (9), p.2028-2037
• Main Authors: Zhiren, Liu, Weilin, Tong, Mingjun, Xue, Chuyuan, Xiang, Yinian, Qi, Dong, Chen, Bin, Hu
• Format: Article
• Language: English
• Subjects: power system protection; power system reliability; power system simulation
• ISSN: 1751-8687; 1751-8695
• DOI: 10.1049/gtd2.12787

With the high penetration of distributed generation and gradual increase in loop network structures, existing over‐current protection in distribution networks is difficult to apply. The use of current differential protection has become an ideal solution, and high performance and commercialization of 5G communication provides an effective way to solve the problem of differential protection channel transmission. Aiming at distribution network differential protection based on 5G, this paper adopted an adaptive frequency conversion transmission mechanism to significantly reduce the data flow of differential protection. In terms of protection strategy, the differential allowable signal and the differential protection startup logic are separated, and a novel action method and protection logic suitable for weak infeed distribution networks are proposed. The strategy significantly shortens the protection action time under wireless communication. Furthermore, a comprehensive synchronization scheme using zero‐crossing synchronization of forward sampling points and cycle numbers based on the second pulse signal was established. This scheme can effectively improve the reliability of data synchronization for differential protection. Finally, the method proposed in this study was verified using the dynamic model experiment of real‐time digital simulation (RTDS). Aiming at distribution network differential protection based on 5G, this study adopted an adaptive frequency conversion transmission mechanism to significantly reduce the data flow of differential protection. In terms of protection strategy, the differential allowable signal transmission logic and the differential protection startup logic are separated, and a novel action method and protection logic suitable for weak‐feed distribution networks are proposed, which significantly shortens the protection action time under wireless communication. Furthermore, a comprehensive synchronization scheme using zero‐crossing synchronization of the forward sampling points and cycle numbers based on the second pulse signal was established. This scheme can effectively improve the reliability of data synchronization for differential protection.