Study and Analysis of Three Port DC-DC Converter in Dual Input Mode for Standalone PV System

Abstract

This paper aims at designing and modelling of three port DC-DC converter and also describes the power management for multiple sources by using three port DC-DC converter based on boost topology. These multiple input converters are capable enough in independent and simultaneous regulation of either of two ports whereas the third port balances the power in entire system. The Multiple input converter (MIC) instead of conventional converters has several advantages such as high efficiency, reduced conversion stages, lower cost, more compact packing, excellent management of the power among the ports and provides centralized control. The three port converter (TPC) topology based on dual input converter (DIC) or dual output converter (DOC) interfaces one PV panel as input source port, one synchronous battery port, and an output/load port. As there are numerous modes of operations, so independent power management in each port is a challenging task. This TPC works in dual input mode (DI), dual output mode (DO), and single input single output mode (SISO). This paper explains detail analysis of all the three modes. Finally, in order to obtain design equations DI mode is analyzed in detail. State space averaging has been developed to obtain various transfer functions under DI mode. Pulse width modulation scheme for the Boost TPC has been designed in order to get smooth autonomous mode transition. A controller has been designed and simulated by using perturb and observe (P&O) MPPT method and output voltage regulation.