Research And Design Of Household Off-grid Single-phase Photovoltaic Power Generation System

With the protection of the environment and the demand of energy, the solar photovoltaic power generation industry is gradually emphasized by all countries. Combined with a good background in solar photovoltaic industry development and the reality of our country rural area electricity problems, this paper proposes a design of household off-grid single-phase photovoltaic inverter. The main work of this paper is as follows:Firstly, this paper introduces the common principle of photovoltaic cells, photovoltaic inverter topology and modulation method and control strategy of photovoltaic inverter. The single phase full bridge inverter topology and the bipolar modulation strategy were selected for the household off-grid single-phase photovoltaic inverter.Secondly, from the main part of household off-grid single-phase photovoltaic inverter, the system is analyzed and the relevant mathematical model is established. The analysis model of the single-phase full bridge inverter is established in the ideal state based on the state-space average method. The virtual space vector control strategy of off-grid single-phase photovoltaic inverter is been given. The basic principle of Hilbert transform is been used to realize virtual vector. The process of realizing the single phase inverter based on virtual space vector control is introduced.Thirdly, this paper builds the simulation model of off-grid single-phase photovoltaic inverter in Matlab/Simulink simulation tools. The virtual space vector control strategy and PI regulator have been used. The simulation results are obtained in the end.Fourthly, the prototype of household off-grid single-phase photovoltaic inverter was implemented, including the hardware design and software design. Experimental results were obtained under laboratory conditions. The experimental results showed that the inverter was reliable and stable. The system had good load capacity and output characteristics.