Abstract
The design and implementation of an energy-management system (EMS) applied to a residential direct current microgrid (DC-µG) is presented in this work. The proposed residential DC-µG is designed to provide a maximum power of one kilowatt by using two photovoltaic arrays (PAs) of 500 W, a battery bank (BB) of 120 V–115 Ah, a supercapacitor module of 0.230 F and a bidirectional DC–AC converter linked to the AC main grid (MG). The EMS works as a centralized manager and it defines the working operation mode for each section of the DC-µG. The operation modes are based on: (1) the DC-link bus voltage, (2) the generated or demanded power to each section of the DC-µG and (3) the BB’s state of charge. The proposed EMS—during the several working operation modes and at the same time—can obtain the maximum energy from the PAs, reduce the energy consumption from the main grid and keep the DC-link bus voltage inside a range of 190 V ± 5%. The EMS and local controllers are implemented by using LabVIEW and NI myRIO-1900 platforms. Moreover, experimental results during connection and disconnection of each DC-µG sections and different on-the-fly transitions are reported, these results focus on the behavior of the DC bus, which shows the DC bus robustness and stability. The robustness of the DC-µG is demonstrated by maintaining a balance of energy between the sources and loads connected to the DC bus under different scenarios.
Highlights
Power consumption increase and the never-ending industrial demand on electrical energy have resulted in a higher requirement of electrical energy generation worldwide and a depletion of conventional generation resources, such as fossil fuels
If the μG is in steady state, with the photovoltaic emulators (PVEs) working in voltage control (VC) mode, and the demanded power by loads in less than 80% of the DC-link maximum capacity, the global management controller (GMC) monitors the state of charge (S◦ C) of the battery bank (BB) and the main grid (MG) with the main aim to change the PVE’s operation mode to MPPT and send energy to the BB or the MG
Algorithm is to keep the DC bus voltage level within the established range, to extract the maximum power from the PVEs, if the energy demanded by the loads is greater than that generated by the PVEs, the missing energy is taken from the MG, if the MG is not available the energy is drawn from the BB
Summary
Power consumption increase and the never-ending industrial demand on electrical energy have resulted in a higher requirement of electrical energy generation worldwide and a depletion of conventional generation resources, such as fossil fuels. I/V characteristic as a decentralized control strategy of a hybrid DC-μG whose structure contains a PA and battery energy storage system and wind turbine generator that can keep the DC-link bus stable even when the energy demand exceeds the maximum power generation Following this trend, a different isolated DC-μG with six operation modes was controlled by using an energy balance method [12]. The DC-μG state machine that controls the global manager considers six operating scenarios to stability of the DC bus, taking advantage of the maximum power of the PAs, balancing the energy generated and demanded by the elements that make up the DC -μG, and take care of the charging and discharging processes of the battery bank, increasing their useful life.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
