Research On Filtering Of High Voltage Direct Current Transmission Based On Novel Converter Transformer

Nowadays, Three Gorges power station power transmitting of our country is constructed actively, the large-scale hydroelectric stations in western are prepared to establish ,large amount western power delivers to the eastern , and large region high voltage power grid interconnection ,which are suitable for adopting HVDC transmission line. Direct current power transmission is good in our country's prospects for development. Converter transformer of direct current power transmission is the key technology equipment, which is not only relates to the alternating and the transmission and transportation, but also involves the run security problems and harmonic suppressing. This thesis,together with the key project 05GK1001-2 of Hunan Province -science &technology of research &manufacture of new-style converter transformer in HVDC power transmitting system, makes numbers of studies in the following aspects:This thesis introduces prospect and application of HVDC power transmission, base on which ,it proposes a hot topic -"harmonic". It proposes some deficiencies of filters mode that tradition converter transformer adopts, so it needs to grope for novel filtering modes.This thesis formulas harmonic(characteristic,non-characteristic and other harmonic) analysis and level calculation of alternate current and direct current side in HVDC power transmission, which provides theory foundation for filtering equipments of HVDC system.This thesis describes connection of novel converter transformer, and formulates in detail harmonic suppression principle in HVDC system based on novel converter transformer. From the degree of magnetic balance, it analyses effect of filtering with emphasis, based on which , it proposes main technology functions when adopts novel converter transformer.The structure and characteristic of passive filter, active filter and hybrid filter are indicated in this thesis, in the same time, it analyses their filtering principle, which provides theory instruction and reference value for the latter part research.In this thesis, through using these formulas, we can calculate the parameters of filter in rectify side and inverter side respectively. According to actual parameters, by means of MATLAB/Simulink, modeling and simulating the rectify side and inverter side of experiment platform respectively. By the contrast of simulation results, we can obtain many advantages when experiment platform adopts novel converter transformer. In the end, it analyzes the application prospect and benefit of the HVDC system that adopts novel converter transformer.