Inherently Sinusoidal Single-Phase Voltage Source Inverter Based on Modified Cuk Cell

Abstract

Renewable energy has become important for electricity generation because of the high air pollution associated with conventional fossil-based energy systems. Conventional fossil-based power plants are gradually transitioning by incorporating renewable energy sources, such as photovoltaic (PV) cells. In a PV system, an inverter converts DC power from solar panels to AC power required to serve common electrical loads. A conventional H-bridge inverter topology has several disadvantages, such as the voltage being not sinusoidal, switching the DC voltage and high common-mode voltage. The common-mode voltage can cause a large leaked capacitive current, which can result in undesirable operation in solar power applications. A common solution to this problem is the addition of a large filter to the input or output of an inverter. An inherent sinusoidal voltage source inverter based on a modified Cuk converter as its basic cell, which simultaneously generates a sinusoidal output voltage and a lower common-mode voltage, is proposed. The proposed topology does not require additional input or output filters. Analytical expressions are derived to confirm the operation of the proposed topology. Simulation results confirm the mathematical analysis. A laboratory-scale experiment is performed to verify the proposed inverter.