Research On Low-power Single-phase Grid-connected Wind Power Converter

With the concept of "Green and Environmental Protection" was proposed, all kinds of new energy exploitation program are in the rapid promotion, the wind power generation has become the hot research topic in the area of renewable resources utilization, and it has become the study focus on how to convert the variable wind energy into power which can be connected to grid. Based on low- power single-phase grid-wind power generation system as the research object, in this paper, the motor side and the grid side topology, control strategy carried out a detailed analysis and study.And design 2kW single-phase grid-connected Wind Power Converter based on DSP.This designed system consists of two parts, First part is the control method of the multiple boost convertor, And the second part is the control method of grid-connection invertor. Firstly it uses three phase uncontrolled rectifier to change the unsteady alternating voltage of the wind power generator into a direct voltage, then through a Boost- Power Factor Correction (Boost- PFC) converter, it boosts the direct boost to a high voltage and reduce the current harmonic, the final adoption of inverter and grid-connection control part to make the wind power of the generator following grid in real time.This boost, regulated part of the first detailed analysis of the working principle of the PFC in turn leads to focus on the average current control strategy and the concrete realization of the concept in this paper, while boost, regulated part of the circuit parameters made by theoretical derivation and calculations. The current-tracking control model is for grid-connection inverter part, a detailed analysis of the PLL SPWM modulation works, it gets software PLL voltage power grid in order to get synchronized with the grid voltage sine wave-unit values, which is used to compare with the triangle wave collected the reference current, the signal with the converter output current value of the sample compared, By PI control and grid voltage feed forward control, and the grid voltage feed forward control can reduce the grid interfering signal in favor of the system stability. Based on establishing a mathematical model of the system, using MATLAB / Simulink to build a system simulation model, the simulation of control strategy show that the system active power high, close to unity power factor grid-connection. Moreover, for the purpose of increasing the control efficiency, this paper uses high performance digital signal processor TMS- 320F2812 as the main controller to accomplish the control masks such as collection,analysis, implementation of algorithm, producing SPWM waves in real time, and so on.According to the requirements of the system design, development of low-power single-phase grid-connected wind power experiment prototype and conducted experimental study. The results show that single-phase grid-connected converter power factor high, stable and reliable system operation to achieve the desired design goals.