The Research Of Single-Phase Photovoltaic Grid-connected Inverter Based On Quasi-PR Control

With the rapid development of society and the improvement of living standard, energy isbecoming increasingly important in our daily life, but now the energy crisis has been a majorproblem which seriously restricts the social progress. The research on renewable energy such assolar energy, wind energy and other clean energy has become an inevitable trend in this societywhich advocates low carbon to protect our environment. Our country has rich solar energy withgreat developing potentiality and photovoltaic (PV) grid-connected generator is a main meansof using it, therefore, the study of its key technology is of great practical significance. What ismore, inverter is the basis of photovoltaic grid-connected generating system which connects PVarrays and power grid, so its significance is evident. This paper involved an in-depth study fromfollowing several aspects surrounding this subject.Firstly, based on the energy situation in our world today this paper expounded theevolution of photovoltaic grid-connected generating technology. Then it introduced the inverterof solar photovoltaic grid-connected generating system in details including its topologyclassification and control technology.Secondly, it analyzed the inverter model and its working status. The control principles of Pcontrol, PI control and PR control were well specified in this paper. Because of thedisadvantages of the three above-mentioned control ways, it put forward quasi-PR controltechnology which can achieve zero steady-state error and elimate the effect of grid voltagedisturbance. Furthermore, it focused on the control principle and parameter settings of quasi-PRcontrol.Thirdly, it introduced the system parameter and software, hardware circuit design. Then, itdesigned two photovoltaic grid-connected inverter system simulation models based onTMS320F2812. After simulating and analyzing the control properties by using the Simulink ofMATLAB, we can find the advantages of quasi-PR control.Finally, it built a1kW photovoltaic grid-connected inverter system based on simulation model. The experimental waves verified the superiority of quasi-PR control technology whichcan make the inverter current synchronize with the network voltage. The system can work withsecurity and stability.