Analysis of unbalanced current malfunction of series complement capacitor bank

Abstract

In this paper, the unbalanced current of the capacitor bank exceeds the boundary in the Panlong I line series repair device of 500 kV fengjie series repair station is taken as an example and the wiring mode of the non-fuse capacitor bank of the station, the configuration of the unbalanced current protection and the theoretical calculation method of the unbalanced degree are introduced. Through the simulation and analysis of the malfunction of capacitor elements inside the capacitor, the influence of different number of capacitor elements breakdown on the capacitance of single capacitor and single series capacitor bank is determined, and the number of failed capacitors that lead to the increase of unbalanced current is inferred. Again by not hurting head and part of the head down the single string, combining the two ways of rapid capacitor of capacitance measurement and eliminating a line after the influence of external factors, such as induction, then quickly completing fault capacitor in series of positioning, finally finding fault by means of only one measurement capacitor and being successful in the balance and replacement, and making it possible to be proved both by the measurement and theoretical speculation to complete the defects of excessive unbalanced current processing. After putting the equipment into operation, the change belonging to unbalanced current of capacitor bank is measured in a certain period of time and the influence of sunshine temperature difference on the unbalanced current of capacitor bank is inferred and the optimization idea of reverse balance of capacitor bank is put forward.