Environmental pollution and economic issues are major problems that results in ascending increase of renewable sources such as solar energy. In order to utilize the current infrastructure of the grid for power transmission and distribution, grid-connected DC-to-AC inverters are needed. However, previously introduced inverters has a two power stage structure or a cascaded structure that increase the power losses and the complexity of the circuit. A new three-phase boost type grid connected inverter, which can be controlled by a new control methodology is proposed in this paper. The proposed inverter has only a single power stage converting DC power to AC power by injecting three sinusoidal currents into grid, which greatly reduces power losses and the complexity of the circuit. Also the proposed inverter can deliver active power from photovoltaic (PV) to the grid while continuously tracking maximum power point (MPP). This topology has several desirable features like simple circuitry, good stability and fast dynamic response. Operation principle, theoretical analysis and design of the proposed topology are discussed. Simulation results performed in MATLAB/SIMULINK software show the effectiveness of the proposed inverter topology.
Keywords: Three-phase, boost inverters, single-stage