Development Of Photovoltaic Grid Connected Micro Inverter

With the development of economy, energy demand is rising rapidly, the traditional energy can not meet the social development needs, a traditional energy with the increase in extraction and less, and the traditional energy sources of pollution, the destruction of the environment, so the new energy has been developed and developed, like solar energy, wind energy the tides, such as nuclear power, new energy applications in expanding the scope. Solar energy is an inexhaustible clean renewable energy become the focus of new energy. With the progress of science and technology, photovoltaic cells are being developed for low cost, high efficiency and high reliability, At present, due to the uneven illumination and shadow appear battery plate crack, affect the power output of photovoltaic cells, in order to overcome the influence of micro inverter, and a single battery plate combination, and adding MPPT equipment, so that can improve the output efficiency of the battery plate, and this combination is more flexible, can be modular production, it can be vigorously promoted.In this paper, the development of grid connected micro inverter is studied by using the interleaved flyback as the research object, and its working principle, the control technology, the maximum power point tracking and the island detection method are analyzed and studied in detail. Firstly, the paper introduces the choice of micro inverter topology circuit, and analyzes the working principle of single ended flyback converter, flyback converter operating in discontinuous and continuous were compared, and ultimately determine the discontinuous conduction mode (DCM); The active clamp flyback inverse converter were studied; The control technology of micro inverter is analyzed and compared, to determine the reasonable control methods and strategies, and ultimately determine the PI control strategy as the control method of this paper; The maximum power point tracking is achieved by using perturbation method; Anti-Island strategy is to use passive active island detection, this method has no effect on the circuit, to ensure the normal operation of the circuit and the protection of equipment; Matlab simulation software is used to build the model and simulate the interleaved flyback micro inverter system, To verify the correctness of the theory; The hardware design and software implementation of interleaved flyback micro inverter are finally implemented.