一种MMC-HVDC交流侧不对称故障诊断方法

• Format: Patent
• Language: Chinese
• Published: 17.05.2019
• Subjects: GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ONOTHER TECHNOLOGY AREAS; MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; PHYSICS; SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORKOPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FORIMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION,DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TESTING

本发明属于电力系统直流输电领域，尤其涉及一种MMC-HVDC交流侧不对称故障诊断方法。实时监测换流站出口处的直流电压，并实时存储电压值；将存储的电压值与函数f(t)进行相乘，对相乘结果进行数据处理，提取故障特征量；建立故障判据，若判据式中有一个成立，则判定交流侧发生不对称故障，否则，判定非此故障。该方法分析了MMC-HVDC交流侧发生不对称故障时，负序分量引起换流站及直流侧发生二倍频波动的原理。并且通过滤波和积分的方法提取直流侧电气量的二倍频分量，并且以二倍频分量作为故障量判据。该方法将提高针对MMC-HVDC交流侧不对称故障的保护选择性，快速性，灵敏性和可靠性。 The invention belongs to the field of electric power system direct current power transmission, and particularly relates to an MMC-HVDC alternating current side asymmetric fault diagnosis method. Direct voltage at a convertor station exit is monitored in real time, and a voltage value is stored in real time; the stored voltage value is multiplied by a function f(t), data processing is performed on a multiplying result, and a fault characteristic quantity is extracted; and fault criteria are established, if one of criterion formulas is satisfied, an asymmetric fault is judged to occur at the alternating current side, otherwise it is judged that the fault is not the asymmetric fault. The method analyzes the principle of occurrence