Analysis of Photovoltaic Fed Partially Isolated Three-Port Full Bridge Converter with the Centralised Controller

摘要

In this paper analysis of an efficient topology of the three-port full bridge dc-dc converter is presented. This topology is promising with the view points of centralised control, compact design as it is capable of interfacing many numbers of ports with less number of switches, low cost, simple and fast power flow management with reduced conversion process. In a stand-alone system this topology is used to interface renewable energy sources and the load along with the energy storage device. Thus the proposed topology interfaces three ports: as one source port, one-bidirectional storage port and an isolated output port. The key feature of this converter is that it performs buck-boost operation on the input port side to obtain power balance in the system with the centralised controller. The centralised controller was implemented by using proportional Integral (PI) controller. Such that it is used to track maximum power from the Photovoltaic (PV) system and to regulate output voltage by controlling the charging and the discharging characteristics of the battery. Zero voltage switching (ZVS) is also achieved in all the switches by using the energy stored in the leakage inductance of the transformer, output filter inductance and capacitance.