Electric Power ›› 2025, Vol. 58 ›› Issue (12): 165-177.DOI: 10.11930/j.issn.1004-9649.202508007

• New-Type Power Grid • Previous Articles     Next Articles

Measurement Error Identification of Protection Secondary Circuit by Fusing Chebyshev Distance and Modified Cosine Similarity Algorithms

WANG Haiming1(), WANG Jianfeng1(), WANG Zhongyuan2, JIANG Jiali2, WENG Hanli2   

  1. 1. State Grid Henan Electric Power Company Hebi Power Supply Co., Ltd., Hebi 458030, China
    2. College of Electrical Engineering & New Energy, China Three Gorges University, Yichang 443002, China
  • Received:2025-08-12 Revised:2025-10-28 Online:2025-12-27 Published:2025-12-28
  • Supported by:
    This work is supported by State Grid Henan Electric Power Company Science and Technology Program (No.521720250004).

Abstract:

Correctly identifying the measurement error of the protection secondary circuit is crucial to improving protection reliability and ensuring stable operation of the power system.Therefore, a method using the entropy weight-based fusion of Chebyshev distance and modified cosine similarity algorithm (EBW-CDMCS) is proposed to accurately identify measurement errors of the protection secondary circuits. Firstly, in order to ensure the accuracy and consistency of data analysis, two sets of measured data undergo standardized preprocessing, and the distance values between the two sets of sampled data are obtained using the Chebyshev distance and the modified cosine similarity algorithm, respectively, to characterize the dispersion of the data. Then, the entropy-based weight method is used to calculate the weights of the two sets of distance values, which are then fused to obtain the EBW-CDMCS distance index. Finally, by analyzing the measured current data of the secondary circuit under normal operating conditions, an appropriate threshold is set. The calculated EBW-CDMCS distance index is compared with this threshold to identify potential measurement errors in the secondary circuit. A 220kV substation model was built based on PSCAD, and simulation results verified the effectiveness and accuracy of the proposed method.

Key words: measurement error identification, Chebyshev distance, modified cosine similarity, entropy-based weight, protection secondary circuit