Title :
High efficiency switched capacitor buck-boost converter for PV application
Author :
Liang, Zhigang ; Huang, Alex Q. ; Guo, Rong
Author_Institution :
FREEDM Syst. Center, North Carolina State Univ., Raleigh, NC, USA
Abstract :
A switched capacitor buck-boost DC/DC converter is proposed for the parallel connected distributed photovoltaic (PV) power generation application: an uncontrolled switched capacitor resonant converter is in parallel connection with a buck-boost converter where their outputs are summed to support the load. The switched capacitor converter is operated with a fixed conversion gain whereas the buck-boost converter is controlled to do the MPPT regulation and only a small portion of energy flows through it. In order to obtain ZVS for switched capacitor circuit in the full load range, an auxiliary inductor is added. The converter´s performance has been evaluated on a 240W experimental prototype. The test results show that 92.5% efficiency is achieved to generate 200V high output voltage from a 60 cells crystalline PV module with Vmpp=30V.
Keywords :
DC-DC power convertors; maximum power point trackers; photovoltaic power systems; resonant power convertors; switched capacitor networks; zero voltage switching; MPPT regulation; PV application; ZVS; auxiliary inductor; crystalline PV module; fixed conversion gain; high efficiency switched capacitor buck-boost converter; parallel connected distributed photovoltaic power generation application; parallel connection; power 240 W; switched capacitor circuit; switched capacitor converter; uncontrolled switched capacitor resonant converter; voltage 200 V; voltage 30 V; Capacitors; Charge pumps; Inductors; Power generation; Switches; Topology; Zero voltage switching;
Conference_Titel :
Applied Power Electronics Conference and Exposition (APEC), 2012 Twenty-Seventh Annual IEEE
Conference_Location :
Orlando, FL
Print_ISBN :
978-1-4577-1215-9
Electronic_ISBN :
978-1-4577-1214-2
DOI :
10.1109/APEC.2012.6166090
