A new three-phase eleven level packed e-cell converter for solar grid-tied applications

Abstract

A new three-phase eleven-level packed E-Cell (PEC11) converter is formed by selecting a quintuple ratio (1:5) between the voltages of solar photovoltaic arrays. The converter consists of three solar panels per phase, highest level of staircase voltage is achieved by the top solar panel. The subsequent voltage levels are obtained using an algebraic formulation with lower two solar panels. The operating modes to get each level are explained. The mathematical modeling is presented with voltage and current equations of three-phase grid. PEC11 converter feeds the current to the grid with closed-loop proportional-resonant (PR) controllers. The nearest level modulation (NLM) technique generates the gating pulses for PEC converter. It provides minimum switching loss and simple control in grid tied mode. This system is simulated in MATLAB/SIMULINK platform, and the power is fed smoothly in both steady-state and dynamic conditions. These results are validated in the real-time simulator (OPAL-RT), which makes this converter ideal for solar applications.

Keywords

• Solar photovoltaic
• Packed e cell
• Power quality
• Renewable energy
• Nearest level modulation