Research On Inverter And Its Control For Photovoltaic Power Generation

Energy is the foundation of social development.With the continuous development of global industrial modernization,human beings are facing great challenges in terms of climate warming,environmental pollution and energy security.With the upgrading of world energy,renewable energy has injected new power into the development and utilization of global energy.Solar energy is a widely distributed renewable energy,which has a very good application value,and the key way of its application is photovoltaic power generation.And photovoltaic power generation technology and other renewable energy power generation technology must use inverter.With more solar power generation needs to be connected to the grid,advanced inverter is needed to maintain the stability of the grid.At present,photovoltaic power generation system mainly has the disadvantages of low energy conversion efficiency,high cost,maximum power point tracking and islanding effect.Under the background of the adjustment of energy strategy and the continuous expansion of photovoltaic power generation market,the research on the topology and control strategy of photovoltaic grid connected inverter has important scientific significance and application value.In order to realize the grid-connected control of the photovoltaic power generation system,the structure of the photovoltaic grid-connected inverter in the engineering case must first be determined.Different classification methods have different structures.After comprehensively analyzing the advantages and disadvantages of each classification structure,this paper selects the three-phase two-stage photovoltaic grid-connected inverter structure.On the basis of determining the inverter structure,by analyzing the characteristics of solar photovoltaic power generation and grid connection requirements,based on the three DC/DC converters of Sepic,Zeta,and Buck-Boost,a new single-stage photovoltaic grid-connected inverter is constructed the main circuit topology.At the same time,the mathematical models of the above three new photovoltaic grid-connected inverters are established,and on this basis,the working principles of nonlinear sliding mode control,fuzzy PID control and single neuron PID control algorithm based on expert system are analyzed in detail.Then use MATLAB simulation software to establish a system simulation model,and use the above three control methods to carry out simulation research on it.Finally,a 1k W system prototype was built based on TMS320F28335,the hardware circuit design and system software design of the four-switch three-phase Buck-Boost inverter experimental device were introduced in detail,and the experimental device was debugged.The experimental results proved the new inverse The correctness of the converter topology and the effectiveness of the control scheme.The proposed new photovoltaic grid-connected inverter can reduce the size and cost of the system,improve the reliability of the solar photovoltaic power generation system,and reduce the complexity of the control system.The research content of this paper will promote the photovoltaic application process of grid-connected inverters,and further promote the development and innovation of photovoltaic power generation technology.The research results of this article will promote the application and promotion of new solar photovoltaic power generation systems to meet high-quality power supply and electricity demand.