The Research on Super Capacitys to Improve the Performance of the Synchronous Generator System Stability

Energy storage system as the power system for the necessary energy buffering equipment of the role is very obvious. Appropriate amount of storage is very important to synchronize the synchronous generator. Widespread applications of energy storage technology by all means will bring great changes to electric power system traditional designing, programming, controlling, adjusting, etc.Super capacitor has the virtues of both high energy density of battery and high power density of electrolytic capacitor, can quickly refresh and discharge, and has long cycle life, high storage efficiency, sound temperature adaptability and environmental character. As the current industrialization of super capacitor basically is Electric Double Layer Capacitor (EDLC), this paper used the Electric Double Layer Capacitor as the super capacitor. For super capacitor of physical characteristics, there are three model of the Electric Double Layer Capacitor that series RC model, nonlinear RC network model and the linear RC network model. The linear RC network model can approximately reflect the physical characteristics and the internal redistribution of charge characteristics of super capacitors.This paper analyzes the operating principle of super capacitor system, and divides into three parts of inverter, bi-directional dc-dc converter and Electric Double Layer Capacitors. According to the operation characteristics of inverter and bi-directional dc-dc converter, this paper made the corresponding control method.This paper establish the simulation model of super capacitor system in Matlab, and the model interconnect the system which have two synchronous generators to verify the designed simulation model can improve significantly the transient and small signal stability performance of the system on the three-phase ground short-circuit fault, and the max power is increase obviously.This design of the super-capacitor energy storage system is useful for the compensation of fluctuating power since one is capable of controlling both active and reactive power simultaneously. And comparing with the system without super capacitor, the system with super capacitor is more stability.