| With lack of energy sources and worsening of ecosystem environment, many countries around the world are positively looking for a kind of sustainable developing and no pollution new energies. Solar source is used as a kind of abroad no pollution for its particular, the substitute of a kind of future the normal regulation energy of the future, photovoltaic generate electricity grid-connected technology among them have become the main form of the solar application. Based on it, this paper introduces residential PV grid-connected system in detail and researches on its control method deeply.The utilization of solar in the manner of PV has been developed swiftly, but it is a main restricted factor of PV generating power's popularization that it is inefficient and high-cost. Aimed at the problems, from improve grid-connected inverter efficient, analyzed and compared the method of the present maximum power point tracking (MPPT) control and grid-connected inverter control, a new method conjugate constant voltage tracking (CVT) rapid start and interrupt & disturb observation. Regarding 0.78 times open circuit voltage as the command start voltage of CVT, and control PV output voltage shift to the MPPT. When the PV output voltage reach command voltage after the interrupt & disturb observation will been used, the demand of swift tracking and high-accuracy for the searching process of PV system is achieved in the theoretically. On the grid-connected inverter control, a novel improve hysteresis-sine current control with double frequency function is designed, and compare with traditional hysteresis current control in different aspects. The corresponding simulation model is set up in MATLAM/Simulink; related simulation is done at the same condition of parameter. The results show that improve hysteresis-sine current control reduce switching frequency and ameliorate total harmonic distortion of system current.According to the result of analysis, the parameters of components in the topology are been decided.
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