Research And Implementation Of The Key Technologies On Shunt Active Power Filter

With the development of science and technology,a lot of nonlinear semiconductor devices have been widely used in various fields.As it brought great convenience to people's life,the serious harmonic pollution has appeared in the power system.The increasing serious harmonic pollution can not only reduce power transfer efficiency,but also cause the equipment overheat and vibration.In addition,strong electromagnetic noise will be made by the high-frequency harmonic in power system,which can disturb the operation of the communication apparatuses nearby seriously.As a kind of power electronic device restraining harmonic and compensating reactive power,the active power filter(APF)can realize tracking compensation for the harmonics with different frequency dynamically.So APF has become one of the research hotspots in the power harmonics control filed.In this thesis the core techniques of the parallel APF have been researched and analyzed to improve the system performance by applying the optimized measures.Firstly the main causation of harmonic pollution in power grid and its detriments have been introduced.At the same time,the existing harmonic control methods have been described,expound the advantages of APF in the field of harmonic control.Then parallel APF is taken as object of study here,and the current situation of its core techniques has been stated explicitly.Secondly,considering APF character and its fesibility,harmonic detection method based on iterative Fourier transform has been adapted to produce command current of the system.Based on the work principle of parallel APF,the improved triangular carrier current control method is used as the current control strategy.Thirdly,according to the topological structure and work principle of parallel APF,simulating models have been established on Matlab / Simulink.A series of simulation experiments have been carried out based on the model.The simulation results have proved that the APF designed on the control strategies can eliminate harmonic and compensate reactive power effectively,and the optimization measure has a good effect on improving APF's performance.Finally,based on the DSP TMS320F2812,the hardware and software of the APF prototype are designed in detail to build the experiment platform,with this experiment platform,we carry out the experiment of harmonic suppression and reactive power compensation after finishing debugging system unit function.The analysis of the experimental results proved the control strategies' effectiveness and practicality,which provides technical basis for related research.