The Research And Design Of Photovoltaic Grid-connected Inverter System

With the development of social economic, rapid population growth and people's living standards, the traditional energy sources will face the threat of using up, coupled with increasingly serious environmental pollution problems, develop new energy sources is imperative. Solar energy has no pollution, no noise, renewable, widely distributed, so received widespread attention around the world, while the solar photovoltaic grid-connected solar PV is the main trends.In the photovoltaic grid-connected systems, the inverter is the core part. the level of its efficiency, reliability will directly affect the whole grid system. In this paper, the single-phase grid inverter control strategy is studied, and also designed lkW single-phase grid-connected solar inverter, based on Infineon's 16-bit MCU.First, compare and analysis the grid inverter control strategy, using triangular wave comparison method of the current track approach as the subject control mode. According to the specific requests, calculation and selection the main parameters, also design the drive circuit and driving power supply circuit. In accordance with the specific needs of control, design peripheral circuits including DC generator voltage, grid current, network-side overvoltage Zero detection, overcurrent protection, PWM output, and designed PCB. Then, the software algorithms and flow chart are achieved.Based on the actual situation, using PSIM simulation software set up a photovoltaic inverter and network simulation platform. After simulation and analysis, the results show that the control strategy can meet the system design requirements, make some foundation for further experiments. Finally built a solar grid-connected inverter experimental platform, and completed the SPWM occurrence, AD sampling, LCD displays and other software debugging.