Study Of Maximum Power Point Tracking In 3kW Grid-connected Photovoltaic Inverter

Photovoltaic power generation is an important problem for study, which contains developing green reproducible energy and improving environment. It has enormous means on economy and society, meanwhile, it has rich value of science studies.In this paper, The hardware implementation of 3kW Grid-connected Photovoltaic Inverter is presented first. The design consists of DC-DC Boost converter and a full bridge converter. A control scheme base on DSP (DSP 56F803) is designed. There are two stages in the control system that can realize maximum power tracking and produce sine wave current that is in phase with grid .The maximum power point tracking method for gird photovoltaic system is mainly discussed in this paper. A simulation model of photovoltaic array has also been studied here. Although the PV array model based on out characteristic is simple, easy to understand and solve, the precision is lower. So we give a model based on physical characteristic, and the fact of illuminate intension and condition temperature is also considered. Its parameters are strictly corresponded with actual parameters, and it has higher precision. The MPPT algorithms used in the model by simulation, the advantages and disadvantages are analyzed and compared .The conclusion has obtained that different actual situation should use different algorithms.A Micro-Controller controlled Boost inverter with the function of maximum power tracking was designed for photovoltaic (PV) array of 100W. The Incremental Conductance and perturbation and observation method are used to maximum tracking power of the PV array, software design is presented in detail.