Design And Simulation Of Hybrid Power Filter In The DC Transmission Project

This dissertation, in terms of the parameter extraction and structure analysis by the 500 KV DC transimission system in some converter station, with intent to reduce the harms produced by the harmonic and reactive power, is developed to propose a revision for the filter field base which is simulated and analyzed it with the Matlab/simulink electric power tools.The dissertation firstly focuses on the harm produced by harmonic to the power grid and the method of harmonics suppression, then analyse the internal and international research actuality of the power electronics.The dissertation mainly focuses on the basic theories of the parallel hybrid power filter and the simulational researches of the DC transmission system and the hybrid power filter. The dissertation provides a draft for the filter field rebuilding—a hybrid power filter whose power grid connects parallelly both the active power filter and the passive power filter, combining both advantages of the two types of filters.Consequently, the method can improve the former filter's performance and minimum the harm produced by harmonic and reactive power to the power grid.A control method of AC side harmonic current detection, based on the keystone analyzing of the parallel hybrid power filter, has been put forward in the study. It achieves the aim of restraining the harmonic current by detecting the AC side harmonic current then controlling the output of the active power filter.The Matlab/simulink electric power toolbox is used to build a model of DC transmission system rectifier side and A hybrid power filter model referring to the keystone analyzing of the parallel hybrid power filter, studying the control method of harmonic current and the parameter extracted in the Converter. Then the result is proved to tally with that of the theoretical analysis. A hybrid power filter model is built afterwards in accordance with the theory and the result, the hybrid power filter model can minimum the harm produced by harmonic and reactive power to the power grid. The last result proves that the draft for the filter field rebuilding is practicable and effective.