摘要
Abstract
In ±800kV YUN-GUANG UHVDC transmission system, in various special conditions, such as investing and cutting filter, adjusting dc power, power grid disturbance, etc, since the charging and discharging process of a lot of capacitors of AC filter, large surge current will flow thought the AC filter, the surge current cause the unbalanced current of high-voltage capacitor of AC filter increased, and cause the unbalanced protection mistake action. So accurately distinguishing the fault and surge of high-voltage capacitor of AC filter is very important to unbalanced protection of AC filter. Though the unbalanced current wavelet transforming and the wavelet transformation modulus maximum, the paper present a new fault distinguishing method of high-voltage capacitor of AC filter. Though PSCAD/EMTDC simulation checking, this method can rapidly, accurately and effective distinguishing the fault and surge of high-voltage capacitor of AC filter, and improve the reliability and validity of unbalanced protection of AC filter.关键词
特高压直流输电系统/交流滤波器不平衡保护/高压电容器/小波变换/PSCAD/EMTDCKey words
UHVDC transmission system/AC filter unbalanced protection/high-voltage capacitor/wavelet transformation/PSCAD/EMTDC分类
信息技术与安全科学
