Integration of Large-Scale Electric Vehicles into Utility Grid: An Efficient Approach for Impact Analysis and Power Quality Assessment

Electric vehicles (EVs) have received massive consideration in the automotive industries due to their improved performance, efficiency and capability to minimize global warming and carbon emission impacts. The utilization of EVs has several potential benefits, such as increased use of renewable energy, less dependency on fossil-fuel-based power generations and energy-storage capability. Although EVs can significantly mitigate global carbon emissions, it is challenging to maintain power balance during charging on-peak hours. Thus, it mandates a comprehensive impact analysis of high-level electric vehicle penetration in utility grids. This paper investigates the impacts of large-scale EV penetration on low voltage distribution, considering the charging time, charging method and characteristics. Several charging scenarios are considered for EVs’ integration into the utility grid regarding power demand, voltage profile, power quality and system adequacy. A lookup-table-based charging approach for EVs is proposed for impact analysis, while considering a large-scale integration. It is observed that the bus voltage and line current are affected during high-level charging and discharging of the EVs. The residential grid voltage sag increases by about 1.96% to 1.77%, 2.21%, 1.96 to 1.521% and 1.93% in four EV-charging profiles, respectively. The finding of this work can be adopted in designing optimal charging/discharging of EVs to minimize the impacts on bus voltage and line current

Development of a PV/Battery Micro-Grid for a Data Center in Bangladesh: Resilience and Sustainability Analysis

Energy resiliency plays an important role in the proper functioning of data centers as they heavily rely on an uninterrupted power supply to ensure smooth operation. In the case of a power outage, the data center’s operation might be hampered, which results in system downtime, data, and economic loss. This issue is severe in developing countries where power supply infrastructures are inadequate and conventional. Microgrids can be an effective solution in this regard. Although several studies developed microgrids to observe the energy resilience benefit for some critical facilities, critical facilities like data centers are often overlooked. In addition, sustainability analysis of a microgrid is also scarce in the present literature. Therefore, one new resilience and sustainability indicator has been developed and implemented in this analysis to fill this gap. For this, new indicators, such as the resilience cost index (RCI) and renewable energy penetration (REP), were used in this study. This study used HOMER version 3.13.3 and REopt software to simulate a robust photovoltaic (PV) and battery microgrid for a hypothetical data center in Bangladesh. A random (48 h) outage was assigned to witness the adaptability of the modelled micro-grid. The suitable size of PV and battery was found to be 249,219 kW and 398,547 kWh, respectively. The system’s USD 18,079,948 net present value (NPV) demonstrates the economic potential of utilizing PV and battery microgrids for data centers. The RCI of the system is found to be 35%, while the REP is 87%. The energy consumption saving of the system is USD 21,822,076. The system emits 652% less CO2 than the grid. The result of this system is also compared with a diesel-based system. After comparison, it is found that the developed PV/battery microgrid provides better environmental and economical service than the diesel generator. During blackouts, the system keeps the data center powered up without interruption while improving energy resilience and lowering carbon emissions. The outcome of this current analysis can serve as a blueprint for other microgrid projects in Bangladesh and other developing countries. By integrating PV/battery microgrids, data centers can cut costs, reduce emissions, and optimize energy use. This will make data centers less reliant on grid services and more flexible to forthcoming development

A Fuzzy-Rule-Based PV Inverter Controller to Enhance the Quality of Solar Power Supply: Experimental Test and Validation

This paper presents the development of fuzzy-based inverter controller for photovoltaic (PV) application to avoid the nonlinearity characteristic and fluctuations of PV inverter output. The fuzzy-based controller algorithm is employed in the PV inverter control system to optimize the duty cycles of the insulated-gate bipolar transistors (IGBTs) and to enhance the inverter outputs with lower harmonic contents and unity power factor. The developed fuzzy-based PV inverter controller is implemented in the MATLAB/Simulink models and experimentally tested in a dSPACE DS1104 process controller. The obtained simulation result of the developed fuzzy-based PV inverter controller is validated with experimental results under different performance conditions. It is seen that the experimental results of the switching signals, inverter voltage and current, control parameters, and total harmonic distortion (THD) of load current and output voltage of the PV inverter are closely matched with that of the simulation results. To validate the inverter performance, the proposed fuzzy-based PV inverter controller outperforms other studies with a voltage THD of 2.5% and a current THD of 3.5% with unity power factor

Hybrid Operation of Super-Capacitor and Battery Storage to Improve Electric Vehicles Performances

This paper proposes a method for battery storage and supercapacitor (SC) hybrid operation toward improving EVs\u27 performance. The adopted concept is established to regulate the level of charge for the SC to suit the immediate storage needs of the EV in such a way as to couple both storage devices. The results demonstrate that the current drawn from the battery has significantly reduced the discharging rate of the battery smoothed out compared to the EV without the SC. Also, the electric vehicle (EV) battery capacity is improved and the implementation of an SC eliminates the abrupt discharge of state of charge (SoC). The SC supports the EV by providing the necessary power when required. The simulation results demonstrate the contribution of SC to improving the battery performance and the reduction in discharging rate. The battery cannot be disconnected, while the SC could be, and power can be exchanged via supercapacitor. The SC is faster than the battery to maintain the optimum SoC level during the tested time (20 sec) at a level of approximately 50%. The obtained results indicate the charging of the SC during the acceleration only. By enhancing the EV stores and transferring its power flows using the proposed hybrid storage system, a more efficient EV can be developed to reduce the frequency of EV battery charging

Micro Energy Storage Systems in Energy Harvesting Applications: Analytical Evaluation towards Future Research Improvement

During the last decade, countless advancements have been made in the field of micro-energy storage systems (MESS) and ambient energy harvesting (EH) shows great potential for research and future improvement. A detailed historical overview with analysis, in the research area of MESS as a form of ambient EH, is presented in this study. The top-cited articles in the field of MESS ambient EH were selected from the Scopus database, and based on articles published from 2010 to 2021, and the number of citations. The search for these top-cited articles was conducted in the third week of December 2021. Mostly the manuscripts were technical and contained an experimental setup with algorithm development (65%), whereas 27.23% of the articles were survey-based. One important observation was that the top 20 selected articles, which are the most-cited articles in the different journals, come from numerous countries of origin. This study revealed that the MESS integrated renewable energy sources (RESs) are an enhancement field of research for EH applications. On the basis of this survey, we hope to identify and solve research problems in the field of MESS and RESs integration, and provide suggestions for future developments for EH applications