Multi-terminal hybrid DC line protection method based on measurement wave impedance phase characteristics

• Main Authors: ZHOU ZEXIN, WANG XINGGUO, DAI ZHIHUI, QIN HAOYU, QIU HONGYI, GUO YARONG
• Format: Patent
• Language: Chinese; English
• Published: 04.11.2022
• Subjects: CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS; GENERATION

The invention relates to a multi-terminal hybrid direct-current line protection method based on measurement wave impedance phase characteristics, which comprises the following steps of: measuring polar line voltage and polar line current of each measurement point, performing phase-mode conversion and S conversion to extract measurement wave impedance phase-frequency characteristics at two ends of a line; and the measured wave impedance phases at the two ends of the line have significant differences under the internal and external fault conditions, and a voltage traveling wave amplitude criterion is constructed according to the corresponding relation to realize fault identification. Through PSCAD simulation verification, the protection provided by the invention can distinguish T-region bus faults, has good anti-transition resistance and noise capability while meeting rapidity, and meets the main protection requirements of a multi-terminal hybrid direct current system line. 本发明涉及基于测量波阻抗相位特性的多端混合直流线路保护方法，通过测量各测量