The Research On One-cycle Control For Pv Grid-connected Inverter

With worldwide lack of energy sources and worsening of ecosystem environment, many countries around the world are actively searching for a new energy source that is continuable development and taintless. Solar energy is much accounted of for its particular. The PV grid-connected system will be the main utilization of solar energy, so it will be developed rapidly.As a necessary part of photovoltaic grid-connected, its conversion efficiency and stability of system are affected by inverter. Therefore, the inverter control strategy is especially important. This dissertation is a part of the of the research on a new integrated and energy conversion system which is national natural science foundation project. in order to transform the solar energy into electrical energy maximum, the dissertation deeply researches the control algorithm of PV grid-connected inverter.Firstly, the dissertation introduces the model of PV array and its characteristics, and compare some usually maximum power point tracking(MPPT) methods, a improved MPPT method based on P&O is proposed. Secondly, analyzing the principle of one-cycle control and its feasibility in detail, Applying one-cycle control in the three-phase grid-connected inverter and concluding the control function based on one-cycle control. Thirdly, with the application MATLAB/SIMULINK, it has established the PV grid-connected system simulation, and simulation waveforms were given to prove the validity of the theory analysis. Finally, the paper introduces the software and the hardware of the control system of inverter on the DSP TMS320F2812. The experimental results prove the accuracy of the controlled algorithm.