Constant switching frequency control-based linear-assisted DC/DC regulator for photovoltaic solar-powered facilities

摘要

Hybrid DC-DC regulators or linear–assisted DC-DC regulators are structures that combine both a linear voltage regulator and a switching DC-DC converter. The main objective of this hybrid topology is to converge, in a single circuit topology, the best of both alternatives: One the one hand, obtaining small voltage output ripple, which is typical of linear regulator structures, and, on the other, achieving good energy efficiency, as in switching alternatives. While the linear regulator fixes the required output voltage to a fixed value with negligible steady-state ripple without the necessity of an output capacitor, the switching converter is devoted to drive most of the load current. In addition, the linear one supplies the required current when the load changes at transient intervals. Current paper deals with the design of a hybrid regulator with constant switching frequency especially devoted to photovoltaic solar applications. The control loop of the system is based on the current–mode technique.