Analysis Design and Control of Three Port Battery Integrated DC DC Converters for LVDC Systems

Abstract

newlineLow voltage direct current (LVDC) systems are increasing becoming popular to newlineintegrate renewable energy sources (RES) and provide power to light loads in residential newlineand commercial establishments. In LVDC systems, multiple DC-DC converters are newlinerequired to connect various elements, including the source, load, and battery. These newlineconverters play a crucial role in achieving objectives such as maximum power point newlinetracking (MPPT), load voltage regulation (LVR), and charging/discharging of batteries. newlineConventional second-order DC-DC boost converters are commonly used to interconnect newlinelow-voltage renewable energy sources with the DC-bus in this system. However, with an newlineincrease in electrical loads, the voltage gains of the conventional boost converter decrease, newlineleading to a significant drop in efficiency. Moreover, the highly intermittent load power newlinedemand in LVDC systems puts an additional burden on the primary source during periods newlineof increased power demand. One solution to this issue is integrating the battery with the newlinepower source, such as a photovoltaic (PV) panel with the additional bidirectional DC-DC newlineconverters, which adds another power processing stage. newlineIn light of the challenges mentioned above, a solution is presented in this thesis. newlineThe focus is on reducing the number of power processing stages and converters through newlinethe introduction of battery-integrated converters. A battery-integrated converter (BIC) is a newlinetype of three-port DC-DC converter that incorporates a battery as an integral part of its newlinedesign. This integration is achieved through the use of additional switches. The battery newlineplays a crucial role in the defined operating modes of this converter, enabling it to regulate newlinethe source current and load voltage while simultaneously charging and discharging the newlinebattery. In situations where the load power requirement is lower than the source power, the newlinebattery may store power, while in cases of excess load, the battery may deliver power. newlineIntegrating the battery into this converter ensures a consiste