DC fault ride-through method for flexible DC power grid

• Main Authors: ZHANG ZHIGANG, WU JINLONG, YAO WEIZHENG, ZHANG JUN, ZHANG HAO, LIU XINHE, XING DENGJIANG, WANG XIANWEI
• Format: Patent
• Language: Chinese; English
• Published: 22.03.2017
• Subjects: CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTINGELECTRIC POWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERATION; REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGYGENERATION, TRANSMISSION OR DISTRIBUTION; SYSTEMS FOR STORING ELECTRIC ENERGY; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE

The invention provides a DC fault ride-through method for a flexible DC power grid. In order to realize the purpose of DC fault ride-through for the flexible DC power grid, DC fault are divided into two categories in the method including DC faults of converter stations and DC faults of DC power transmission lines. Two independently controlled protection systems are set for the converter stations and DC circuit breakers. When a DC fault occurs, DC fault ride-through of the flexible DC power grid is completed by coordinating and controlling the DC circuit breakers and the converter stations for different types of faults. During the DC fault occurring process, related non-fault converter stations and power transmission lines work normally and may not be affected, thereby realizing stable operation of a flexible DC power grid. 本发明提供了种柔性直流电网的直流故障穿越方法。该方法以实现柔性直流电网的直流故障穿越为目的，将直流故障分为两类：1)换流站直流故障；2)直流输电线路直流故障。该方法为换流站和直流断路器设置两个独立控制保护系统。直流故障发生时，针对不同的故障类型，通过协调控制直流断路器和换流站来完成柔性直流电网直流故障穿越。采用该方法，在直流故障发生过程中，非故障相关换流站和输电线路的正常运行