Modelling analysis and design of bidirectional interleaved switched capacitor dc dc converter for microgrid applications

Abstract

The production of electricity nowadays has been modernized with the introduction of microgrids. The microgrid is an independent energy system by which a locality is being served and it is an interconnection of renewable energy sources, power electronic devices and loads. The microgrid employs renewable energy source as a main source of power which has less maintenance cost, reduced transmission losses, reduced emissions and improves efficiency. The renewable energy is not available continuously and needs to be managed for continuous supply of power. So energy storage devices are used to balance the power supply during the non availability of renewable energy sources. To interface the energy storage devices, renewable energy sources and loads, power electronic converters are used. As the flow of energy is required to be operated bidirectionally, bidirectional converters are mostly preferred for microgrid. This work proposes a Bidirectional Interleaved Switched Capacitor DC-DC converter with the battery as an energy storage device for microgrid applications. The interleaving technique adapted in the converter reduces the ripples in the input side. The switching capacitors in the converter topology increase the voltage gain of the converter. The converter operates in boost (step up) and buck (step down) modes and enables power flow in both directions. A PI controller is involved in aiding the converter to operate and switch to both modes automatically. The converter can be designed and developed based on the applications. The Bidirectional Interleaved Switched Capacitor DC-DC is designed for a solar powered microgrid and its modes of operation is explained and analysed. newline