Executive Summary : | This proposal aims to add on to the intense research going on in the field of renewable energy. Particularly, this proposal focusses on interfacing different energy sources to the grid, using a more efficient and power-dense power electronic converters. Harnessing renewable energy in the present- day world is essential and is the way forward. Considering solar energy, solar cell efficiency developed in the lab is still less than 20%. So utilizing this 20%, with minimal losses, is the responsibility of power electronics engineers. The energy sources, storage sources, and their characteristics are different from the load requirement, and therefore a power electronic system has to be incorporated. Generally, the trend is to use a separate power electronic converter to interface each energy source and have a common DC link, which then acts as an input to another power electronic converter, which does the power conversion to interface with the grid. This proposal tries to address two of the issues in this. One is how to integrate multiple energy sources using a single converter, which invariably improves efficiency and power density by investigating the optimized design of three-port high-frequency transformer. Secondly, there is a serious stability concern in the DC link, where multiple DC sources are injecting their power, which is not addressed so far, especially in the context of multiple DC sources. In particular, this project aims to build and investigate a multi-input port converter and its limits and capabilities while integrating with the grid. Although this proposal is focussed on renewable energy, where the multiple input sources considered are solar photovoltaics and the battery bank, it can be extended to applications in hybrid electric vehicles or fuel cell vehicles. The first step towards achieving this goal is to develop dynamic models for the converters required for doing this power conversion. Here two power electronic converters are needed, one for interfacing multiple energy sources using a high-frequency transformer, which is a DC-DC converter. And another for grid integration, which is a DC-AC inverter. These dynamic models will help in designing controllers for their simulation and hardware testing. The experiments consisting of these cascaded converters, will test the different power flow scenarios that arise from the interaction between the three energy sources; Solar PV, Energy storage, and the grid. |