Analysis and design of single-phase current-source grid-connected PV inverter

Abstract

This paper investigates the performance of a 150 W single-phase current-source grid-connected inverter for photovoltaic (PV) applications. The constant-current source is realized using a large DC link inductor and the inverter is implemented using a single boost switch, a H-bridge inverter and a CL output filter. Although the DC link inductor causes the inverter to be less efficient than an equivalent voltage-source inverter, it offers lower cost due to the zero-current switching and lower number of components. In addition, the output current is easily controlled using the boost switch and offers simple open-loop and feed-forward control. The paper compares the simulated and measured inverter performance with regards to output power, total harmonic distortion and power factor. Additionally the scaling of the concept to a higher power (1.2 kW) inverter was also investigated using simulations.