Modelling and analysis of a dc electric spring with z-source DC-DC converter

In this thesis, a DC-Microgrid that is supplied from renewable energy sources (RESs) is developed and presented. To keep the DC-Microgrid voltage stable, a DC Electric Spring (DCES) is applied to model to remove voltage fluctuations due to intermittent generation of Renewable Energy Sources. The fluctuating voltage of the system input power is absorbed by the series connected Non-Critical Load and DC Electric Spring branch. In order to maintain a stable DC voltage for Critical Load, the voltage quality on Non-Critical Load can be sacrificed. DC Electric Spring tracks the supply side voltage continuously and generates required voltage from battery bank thanks to Half-Bridge DC-DC Converter and Z-Source Converter.The key advantage of Z-Source Converter is the high level voltage gain and satisfies low battery bank costs. System is modelled in MATLAB/Simulink and simulation results are presented.