The Research On The Novel Reactive Power Compensation Device And The Hybrid Filter

This thesis includes two sections: one is the research on a novel reactive power compensation which concludes its structure characterization of main circuit and principle of operation; the other is the study of hybrid filter.It is great significance of the technique of dynamic reactive power compensation to improve the quality of electric energy, protect the safety control of power line and steady operation. Based on the tradition of the dynamic reactive power compensation, a novel technique of controllable power capacitor is presented, When simulated by Matlab, the flow angle of Gate Turn-Off Thyristor is adjusted, the voltage and current of the capacitor is changed, the continued current is derived in a period which can lead the equivalent electric capacity to change periodically. The voltage waveform is analysed on mathematic,the flow angle of Gate Turn-Off Thyristorβchanges form 90 to180 ,the equivalent capacitance is continuously changed form C/2 to C, then it can realize the purpose of dynamic reactive power compensation. Though programming in the Matlab, we find the system current only has odd harmonic which can be filtered by the power filter.This paper gives a detailed analysis of the form and design guideline of the hybrid power filter, then describe the structure characterization of the main device. At last, Taking a commutating system for example, simulation result shows that the distortion factor of the current reduces from 21.4 percent to 5.19 percent after assembling the filters and there is no phenomenon of harmonic amplifying. So the correctness and feasibility of this method is further confirmed.The research is summarized in the end of the thesis and gives a prospect of the future effort.