Research On A New Control Strategy Of Excitation System

Power system stability plays an important role in the safe operation of network, which will cause enormous economic losses and calamitous consequence when it is destroyed. There have been lots of bitter lessons existed in the world. Among these methods to improve stability of generators, one of the most efficient and economic way is to make the performance of excitation device better, which has been acknowledged generally. But the problems in the control system of excitation device such as its robustness, fast response and efficiency are still not well resolved.The main subject of this dissertation is the research on the control mode of excitation system, which is a subsection of Sanxia Electromechanical Equipment Research. In the paper we introduced the origination of the problem of power system stability and its principle mathematic analysis method. Then the effect to the stability of power system by excitation system is illuminated in detail. Through the deep study of F. D. Demello dynamic model of electromechanical transition and synchronous generator theory, we proposed a new control strategy of excitation device that can eliminate the negative-damping phenomenon, which is directly against the cause of producing negative-damping represented as low frequency oscillation in the system. By the static stability analysis and dynamic simulation analysis, this additional excitation control can increase the system damping and improve system stability with very good robustness. In the thesis we described the engineering realization scheme of this control strategy. Now the relative hardware is in development.