Power capacitor bank is an important device in power system

the damage of individual element due to various reasons will develop serious fault and lead to damage of capacitor bank. For solving this problem

in this paper

a complete new warning method for the early stage fault of internal element in double star capacitor bank is proposed in accordance with theoretical analysis of element damage of the capacitor bank at early stage: Imbalanced current variation method at initial vector to zero. The variation of imbalance current is calculated by way of detecting the current between two arms of the capacitor bank together with three-phase current

and the occurrence of the fault is judged through vector comparison.The new warning method is also verified by various data simulated by the system. Application of the method is convenient for the operation management of capacitor bank and provides new way in finding out the fault at early stage.