The Research Of PV Grid-connected System

when the energy crisis of the world is serious and global environment problem deteriorate, applying clean and regeneration resource widely have been main direction of the energy stratagem. Due to solar energy is one of the most clean, practical and large scale regeneration energy resources, it abstract all realm attention. During all kinds of solar energy applications, the PV grid-connected system is most important trend of utilization of solar energy. Because of the solar industry having no united standard, all kinds of PV grid-connected system have been applied. Under this background, this dissertation compares serious different topology and control method of PV grid-connected system. When considering the large change of the output voltage of PV array and reliability of system, the dissertation point out topology of grid-connected inverter based on Z-source converter.Comparing the insulation mode of PV grid-connected system,serious topology of different main circuit and diverse control method, this dissertation recommend the topology composing with inverter and Z-source converter. Secondly, through analyzing three different control methods of boosting voltage of Z-source converter and three different SPWM current control of inverter, it connect both of them to get basic ideology of accomplishing inverter and MPPT.Based related analyze and research, dissertation supply project of whole hardware configuration and control stratagem. And it introduces the design and calculation of system hardware; provide topology of main circuit, calculation and chosen relative parameters and design of control circuit. Building model of system simulation, the dissertation introduce function of each sub-model and provide result of simulation.The results demonstrate that the system can implement the control scheme proposed in this dissertation perfectly. The system operates stabilization and has good performances.