A Single-Stage Isolated AC–DC Converter to Interlink Utility Grid and Renewable Energy Sources in a Residential DC Distribution System
Parthasarathy Nayak, Kaushik Rajashekara
Abstract
This article proposes a single-stage isolated PWM rectifier topology to interlink utility grid and renewable energy sources in a 380-V dc distribution system for residential applications. The proposed topology provides both the power factor correction and output dc voltage regulation within a single power conversion stage. Furthermore, it includes an integrated flyback-based active lossless clamp (ALC) circuit to mitigate the device overvoltage issues generally noticed in the isolated single-stage PWM rectifiers. Thus, low-voltage-rating devices can be selected. The regenerative feature of the flyback ALC circuit along with soft-switching of the main converter structure helps in realizing higher efficiency. A dual-duty hybrid control algorithm is also reported to improve the converter performance. An SiC mosfet-based 1.5-kW hardware prototype is developed. The converter performance is evaluated from the experimental results obtained during both the steady state and dynamic operation. Comprehensive performance analysis and comparison study have also been presented in this article.