A single-ended high-impedance fault protection scheme for hybrid HVDC transmission lines based on coordination of control objective

• Published in: International journal of electrical power & energy systems 2024-10, Vol.161, p.110187, Article 110187
• Main Authors: Ma, Ruizhi, Chen, Yu, Wen, Minghao, Han, Ke
• Format: Article
• Language: English
• Subjects: Coordination of converter control objective; FRT; High-impedance fault; Hybrid HVDC; Single-ended protection
• ISSN: 0142-0615
• DOI: 10.1016/j.ijepes.2024.110187

•The scheme presupposes the control strategy and objective of the double-ended converter during the FRT stage.•The scheme is independent of communications with high reliability. The proposed protection scheme is simple in principle and is not affected by the strength of boundary elements.•Theoretical analysis and simulation verification confirm the effectiveness of the scheme in identifying high-impedance faults. Hybrid HVDC transmission technology advancement has led to significant progress. A reliable and effective DC line protection scheme is crucial for DC transmission systems. The traditional protection schemes suffer from insufficient sensitivity and reliability during high-impedance faults on DC lines. To address the issue, this study introduces a hybrid HVDC line single-ended protection scheme based on the coordination of converter control objectives. In the fault-ride-through(FRT) stage, different control strategies and objectives are applied to the converter based on the fault pole and fault direction identification results. Internal and external faults are discerned by calculating measured voltage with the coordination of the converter control objective. This approach maintains heightened sensitivity to high-impedance DC line faults. Moreover, it operates independently of double-ended communication and demands a low sampling rate. Extensive simulation results robustly substantiate the efficacy of the proposed protection scheme.