AC and DC filter capacitor banks in China generally use H-bridge structure,but some converter stations use π-type structure capacitor banks,and the off-line test method for unbalanced current of H-bridge capacitor banks is not applicable any longer. In this paper,a new method of indirectly measuring unbalanced current is proposed by forming a π-type capacitor bank into an H bridge. And the method de-rives the calculation formula and simulates such three methods of forming the H bridge as resistance,capac-itance and inductance. For reducing the influence of on-site electromagnetic interference on the measure-ment accuracy,the method of testing unbalanced current at multiple frequency points is used for on-site test-ing. The results show that the theoretical idea of the new method is correct and can accurately measure un-balanced current.
关键词
π型电容器组/电阻桥臂/不平衡电流
Key words
capacitor bank as π type structure/resistor bridge arm/unbalanced current
维普
万方数据