Research Of Small Power Household Photovoltaic System With Energy Storage

The increasingly serious energy crisis and pollution of fossil energy to the environment promote the development of generation technology with renewable energy, in which. Photovoltaic power generation has got more and more promotion and application with some advantages, such as the large storage, pollution-free. The development of the distributed generation system and the difficulty of transmission in Chinese remote areas bring a bright future for our photovoltaic industry.The small power household photovoltaic energy storage system is studied and designed in this thesis. The system which integrates the boost controller part, inverter part, energy storage part, is easy to install and use. It has good business prospects. The thesis first analyzes the principles of boost circuit, full-bridge inverter and storage circuit, and introduces the SPWM modulation of inverter circuit in detail. The system will produce serious leakage current in grid-connected mode, due to the non-isolated topology. The thesis explains the suppression principle of leakage current, and a common filter was add to circuit to suppress the leakage current, which the feasibility of the design is verified by simulation.In this thesis, the closed-loop design, photovoltaic characteristics, MPPT method and the energy storage charging scheme are all investigated. And finally, the variable step incremental conductance MPPT method and three-step charging scheme are used for PV system.A5kW small power household photovoltaic energy storage system was designed based on theoretical research foundation of this thesis. IGBT and MOSFET were adopted as the choice of switching device, and the parameter of inductors and capacitors are designed. According to the system requirement, the sampling and protection circuit are also designed in this thesis. And finally, the design and port assignment of the DSP chip TMS320F28335is introduced.In the last, the simulation of the PV system and the test of the prototype were done. The simulation and test verified the high efficiency of the topology and the modulation with maximum efficiency of94.4%. It is verified that the MPPT method was feasible by simulation, and the steady-state tracking efficiency was maintained at above99%, to maximize the use of solar panels. The function of bi-direction storage circuit is also verified by simulation.