Low voltage hybrid renewable energy system management for energy storages charging-discharging

Abstract

As it is known, Hybrid Renewable Energy Systems (HRESs) development are aimed to increase the productivity and optimize the power generation produced by one or more connected sources. Such HRESs are always integrated with some kind of energy storage systems to satisfy the load demand during the Off-Period condition of the renewable energy sources. Off-Period condition can be categories into two phases: 1) low voltage output/low power and 2) zero voltage output/zero power. During both phases the energy storage systems will be the primary energy supplier to the load. Low voltage output produces a certain amount of voltage by the HRESs but it is insufficient to supply directly to the load. Thus, the low voltage output condition is able to be used to charge the energy storage systems such as the battery storages but not the zero voltage output condition. However, the low voltage output from the HRESs is not given a serious consideration and is always ignored of its importance. Even though the low voltage output is relatively considered unable to charge the energy storage systems but with the advancement of power electronics engineering the low voltage can be used to perform energy storage systems charging. With that, this research proposes to 1) design and develop the Hierarchical Switching and Control Process controller for charging-discharging the Battery Energy Storage System using low voltage output and 2) integrate the DC to DC Boost Converter to step-up the low voltage for Battery Energy Storage System charging using the Simulink/Stateflow in MATLAB software. Based on the results obtained the Hierarchical Switching and Control Process Controller and DC to DC Boost Converter has validated the proposed idea to step-up the low voltage for Battery Energy Storage System charging - discharging.