Research On The Grid Side Converter Of Variable-Speed Constant-Freuqency Wind Power Generation System

At present, the situation of energy shortage and environmental pollution is getting steadily worse. As a kind of regenerated green energy, the utilization and exploitation of wind energy is of great significance. Therefore, countries in the world attach great importance and compete against each other to develop it by spreading new technology. The structure of the wind power generation grid-side converter and the controlling method of it have becoming the hot spots for extensive research and application. The advantages and disadvantages of its function have a profound effect on the operational efficiency and stability of wind power generation and grid--connected system.This paper firstly introduces the current research status of the wind power generation both at home and abroad, and then analyses the topological structure of the grid-side PWM converter. On the basis of detailed research on the basic principles of the space vector pulse width modulation(SVPWM), this paper put forward the mathematical model of the grid-side PWM converter which is based on the voltage and current closed-loop strategy. At last, on the Matlab/Simulink simulation platform, it simulates the operational control when the grid-side converter working in unit power factor rectifier and inversion, the changing form rectify to inversion and removing load suddenly. The simulation results show that the wind power generation grid-side converter, which is based on grid voltage orientation, has the following characteristics:of good output performance; of little harmonic wave; bidirectional energy flow and so on.On the basis of previous theoretical analysis and simulation verification, an integrated simulation experiment platform of 15kW doubly-fed induction generator (DFIG), which is based on DSP (TMS320F2812), has been built. It designs the controlling circuit of grid-side PWM converter which includes signal acquisition circuit, signal processing circuit, IPM drive circuit; guard circuit and so on. Then gives the main program flows of the sofeware.At last, it carries out an integrated experimental research on VSCF wind power generation grid-side converter. After the introduction and analysis of the experimental condition and result, it shows the unit power factor which is realized by the grid-side converter. It eliminates the disadvantages existing in traditional rectifier circui t:of high harmonic contentand of low power factor. It also realizes the stable tracking of the DC-side voltage and unit effective properties of the power factor effectively. The correctness, effectiveness and feasibility of the experimental design have been testified. It has excellent practical value in engineering.