Simulation of Two-Level Photovoltaic Grid-Connected System Based on Current Control of Hysteresis Band

As the output power of the photovoltaic (PV) cell changes with the insolation , PV cell temperature and cell voltage changing. It is necessary to control the operating point to draw the maximum power of the PV cell in order to increase system efficiency. In this paper, two-level single phase PV grid-connected system is designed, which mainly includes PV cell, BOOST circuit, inverter, filter and the grid. The forestage BOOST chopper adopts Incremental conductance algorithm to implement Maximum Power Point Tracking; The latter controller for the inverter system adopts current control of hysteresis band scheme. According to the proposed control schemes, the phase and frequency of grid-connected current is the same as grid voltage, with the result of unity of the power factor for power grid. The single phase PV grid-connected system is built by MATLAB/SIMULINK, the simulation results show that this system can be really good to realize the Maximum Power Point Tracking and the current output of the inverter satisfied with grid-connected conditions.