Development Of3kW Photovoltaic Grid-Connected Inverter System

With the rapid development of economic and people’s unrestrained exploitation of thelimited resources, the development of resource has being a pressing task. Solar energy asrenewable energy has gained worldwide attention. Photovoltaic Inverter is an energyconversion device which converts solar energy to electrical.Thus its output characteristichas relationship with the whole power system performance and life. Under thisbackground, this thesis discusses about the research and development of PhotovoltaicInverter as follows:The advantage and disadvantage of different topology of Photovoltaic Inverters areanalyzed and a one-phase, two-stage, transform-less scheme is selected to meet thecommands. The control circuit which is based on DC/DC conversion, DC/AC conversionand DSP as a core is designed. The principle and structureof the associated circuits arediscussed in detail in this paper.After analyzing the generation of network load currentlagging power factor, a simple lagging power factor angle compensation algorithm isproposed. To improve the power factor and compensate the reactive power of the grid,reducing the grid energy loss during transmission.By using Saber software, the simulationmodel of Photovoltaic Grid-Connected Inverter is build and the validity of selectedstructure, control circuit, control tactics, and the angular control strategy of thecompensation of the load current lagging power factor is verified.Based on the theoryabove, the hardware and software of3kw PV Grid-Connected Inverter is designed.Experiments on maximum power point tracking, on-grid invert, improve the grid powerfactor and long-term operation is accomplished. The results show that the system meets alldemand and has good performance.