Open Access

ARTICLE

Distribution Line Longitudinal Protection Method Based on Virtual Measurement Current Restraint

by Wei Wang¹, Yang Yu¹, Simin Luo^2,*, Wenlin Liu², Wei Tang¹, Yuanbo Ye¹

1 Power Dispatching Control Center, State Grid Anhui Electric Power Co., Ltd., Hefei, 230022, China
2 School of Electrical Engineering, Beijing Jiaotong University, Beijing, 100044, China

* Corresponding Author: Simin Luo. Email:

Energy Engineering 2024, 121(2), 315-337. https://doi.org/10.32604/ee.2023.042082

Received 17 May 2023; Accepted 06 September 2023; Issue published 25 January 2024

Abstract

As an effective approach to achieve the “dual-carbon” goal, the grid-connected capacity of renewable energy increases constantly. Photovoltaics are the most widely used renewable energy sources and have been applied on various occasions. However, the inherent randomness, intermittency, and weak support of grid-connected equipment not only cause changes in the original flow characteristics of the grid but also result in complex fault characteristics. Traditional overcurrent and differential protection methods cannot respond accurately due to the effects of unknown renewable energy sources. Therefore, a longitudinal protection method based on virtual measurement of current restraint is proposed in this paper. The positive sequence current data and the network parameters are used to calculate the virtual measurement current which compensates for the output current of photovoltaic (PV). The waveform difference between the virtual measured current and the terminal current for internal and external faults is used to construct the protection method. An improved edit distance algorithm is proposed to measure the similarity between virtual measurement current and terminal measurement current. Finally, the feasibility of the protection method is verified through PSCAD simulation.

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Keywords

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