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The article explores possible solutions to bring renewable energy and reliable power back to Puerto Rico amid the effects of climate change and an aging infrastructure. It reports the release of the Puerto Rico Energy Resilience Fund for use in projects such as rooftop solar installations, as well as the cancellation of coal-fired generation by 2028, renewable energy transition efforts, and the implementation of solutions like community-scale microgrids and solar energy cooperatives.

Imbalances are one of the major challenges encountered during DC microgrid operation. This study presents a DC-voltage-balancing strategy that uses a high-performance controller. Indirect-sliding-mode (ISM) control is used in the current control loop and voltage loop to achieve fast dynamics, and a conventional proportional-integral (PI) controller with optimized parameters is designed. The performances of the nonlinear and linear controllers are compared and verified through a simulation performed using MATLAB/Simulink, along with an experimental analysis. The voltage-balancing dynamics of the two controllers are also compared. These results demonstrate that the ISM scheme can achieve better DC voltage balancing performance in the transient regime than the conventional PI scheme for the DC-DC converter. [ABSTRACT FROM AUTHOR]

Renewable energy sources (RES) are becoming potential reserves in power systems owing the capability of generation at customer ends by operating as a Microgrid. An efficient controller is indispensable for a stable and reliable power supply in the Microgrid premises. In this work, we propose an Iteratively Sustained Sliding Mode Controller (ISSMC) working in a two-level hierarchical architecture to respond appropriately for continuous tracking of uncertainties in a DC Microgrid. The DC Microgrid comprises of Solar Photovoltaic (PV) array source, battery-supercapacitor (SC) based hybrid energy storage system (HESS) and dynamic loads coupled at a DC-link. The proposed controller appropriately tracks the set points provided by an energy management algorithm at secondary level with the objective of power balance and constant voltage maintenance at the DC-link node. During uncertain conditions such as fluctuating irradiance pattern, variations in load demand and occurrence of faults within the microgid, the proposed controller retains the error signal over the sliding bounds by iteratively sustaining the sliding regime response of the Sliding Mode Control (SMC) law using Iterative Learning Control (ILC) method. The simulations were performed to evaluate the performance of the proposed controller under different operating conditions such as the step variations in irradiance and load demand profile. The controller response is recorded to analyze its steady-state operation, tracking accuracy, and effective cooperation of sources for energy management. Also, the effectiveness to preserve the sliding regime is demonstrated during power disturbances on the demand side of the DC Microgrid involving constant power loads and AC loads. It was found that the proposed controller provided adequate tracking accuracy and fast restoration to the steady state under all the operating conditions. To further emphasize the effectiveness of the controller, the simulations were also conducted for a real-time irradiance pattern. Furthermore, the controller behavior was also evaluated in the controller hardware-in-the-loop (C-HIL) test setup using a microcontroller unit TMS320F28379D Delfino Launchpad. [Display omitted] • Iteratively Sustained Sliding Mode Controllers are designed for the DC Microgrid • Performance of the controllers are analyzed during power disturbances. • A comprehensive energy management algorithm ensures proper utilization of power sources. • Stability of the proposed controller is verified. • Controller Hardware-in-the-loop (C-HIL) tests are done for the validation. [ABSTRACT FROM AUTHOR]

GoodWe, a global leader in solar inverter manufacturing and renewable energy solutions, has released its 2023 Corporate Social Responsibility (CSR) report. The report highlights GoodWe's efforts in corporate governance, product responsibility, sustainable operations, industry engagement, employee development, and community contributions. Throughout 2023, GoodWe pursued sustainability development through various objectives and initiatives, such as investing in research and development, hosting workshops to enhance product quality, achieving green power generation, obtaining certifications for inverter products, launching community display centers, providing employee training, improving the supply chain's green performance, and donating to the construction of public welfare distributed power stations. GoodWe plans to extend its efforts in the wider ESG field and drive tangible business results for a more sustainable future. [Extracted from the article]

Hopewind, a global provider of renewable energy solutions, is leading the way in the electrical revolution with its grid-forming technology. This innovative technology ensures the stable and reliable operation of power grids, particularly in the context of renewable energy integration and decentralized networks. Hopewind's achievements in grid-forming technology include receiving the world's first grid-forming certification and operating the world's first grid-forming wind farm. They have also expanded their grid-forming technology into solar power with their cutting-edge 385kW string PV inverter. Hopewind's commitment to innovation has earned them recognition and nominations for prestigious awards. [Extracted from the article]

Battery Energy Storage Systems (BESS) are crucial for storing renewable energy from sources like solar and wind. They bridge the gap between when renewable energy is generated and when it's needed by storing excess energy during peak production times and discharging it back to the grid when demand is high. BESS offers benefits such as grid stability, peak shaving, improved efficiency, and renewable energy integration. They also have applications beyond the grid, including supporting microgrids, electric vehicles, and industrial facilities. Enercap's supercapacitor technology is a promising solution for grid-scale energy storage systems, offering benefits such as high energy density, rapid response, long cycle life, high efficiency, scalability, modularity, and temperature tolerance. [Extracted from the article]

The article discusses how Cincinnati/Northern Kentucky International Airport (CVG) has become a leader in adopting new technology and innovation. The airport focuses on four areas of innovation: Transport, Connect, Clean, and Secure, all driven by automation. CVG collaborates with universities and local organizations to drive innovation and economic growth in the community. The airport has implemented various initiatives, such as using airport campuses to stabilize the grid and partnering with The Cincinnati Museum Center for exhibits. The COVID-19 pandemic has accelerated the push towards automation, with robots being used for surveys and food delivery. CVG is committed to sharing its technology and collaborating with other airports to improve the passenger experience. The airport is also involved in regional air mobility initiatives and is working towards FAA certification. The article emphasizes the importance of consistency in security procedures and training to address the needs of travelers with special requirements. [Extracted from the article]

The article discusses the efforts of the U.S. Army Engineering and Support Center - Huntsville to address climate change impacts in acquisition strategies, planning, and infrastructure upgrades. The center focuses on environmental cleanup, installation support, energy conservation, systems engineering, and construction. They utilize energy savings performance contracts (ESPCs) to partner with energy service companies and make facility improvements. The ESPC program has resulted in significant savings and reductions in energy use and greenhouse gas emissions. The center also works on projects to improve energy efficiency and resilience at various military installations. [Extracted from the article]

The Department of the Air Force is investing in microgrid solutions to increase energy resilience and mission readiness in the face of threats. Microgrids are smaller power systems that can disconnect from the main grid and continue to provide power during outages. Examples of successful microgrid installations include Kadena Air Base in Japan, which sustained operations during a typhoon, and Yokota Air Base, which can island from the commercial grid in emergencies. The Air Force is also exploring innovative technologies such as direct current microgrids and geothermal generation. Numerous microgrid projects are currently underway across the Air Force. [Extracted from the article]

The article focuses on Endeavour Energy, a utility company, and its successful launch of the Bawley Point and Kioloa community microgrid, demonstrating its commitment to enhancing grid reliability in rural areas. Topics include the rationale behind establishing the microgrid in remote locations, the role of distributed energy resources (DER) in bolstering community resilience during extreme weather events, and the approach involving community consultation in implementing the project.

The article offers concepts for keeping U.S. military forces supported with small power grids. Topics discussed include reasons the Department of Defense (DOD) needs to advance microgrid systems, vulnerabilities of the DOD's reliance on the national electric grid system, and essential tasks for a Defense Energy Architecture (DEA) to address the emerging energy needs. It also mentions efforts of the DOD to address the potential threats posed by climate change.

Purpose: This paper aims to introduce a new fault protection scheme for microgrid DC networks with ring buses. Design/methodology/approach: It is well recognized that the protection scheme in a DC ring bus microgrid becomes very complicated due to the bidirectional power flow. To provide reliable protection, the differential current signal is decomposed into several basic modes using adaptive variational mode decomposition (VMD). In this method, the mode number and the penalty factor are chosen optimally by using arithmetic optimization algorithm, yielding satisfactory decomposition results than the conventional VMD. Weighted Kurtosis index is used as the measurement index to select the sensitive mode, which is used to evaluate the discrete Teager energy (DTE) that indicates the occurrence of DC faults. For localizing cable faults, the current signals from the two ends are used on a sample-to-sample basis to formulate the state space matrix, which is solved by using generalized least squares approach. The proposed protection method is validated in MATLAB/SIMULINK by considering various test cases. Findings: DTE is used to detect pole-pole and pole-ground fault and other disturbances such as high-impedance faults and series arc faults with a reduced detection time (10 ms) compared to some existing techniques. Originality/value: Verification of this method is performed considering various test cases in MATLAB/SIMULINK platform yielding fast detection timings and accurate fault location. [ABSTRACT FROM AUTHOR]

This paper focuses on the event-triggered quantized secondary regulation problem for islanded alternating-current (AC) microgrids with actuator faults. In order to handle the actuator faults, including bias faults and partial loss of effectiveness faults, a distributed secondary regulation strategy is proposed, which achieves voltage and frequency regulations, as well as power sharing. Due to the limited communication bandwidth, a uniform quantizer is introduced for information transmission. Meanwhile, to save system resources and relieve the communication burden, an adaptive event-triggered mechanism is designed. Finally, the proposed strategy is validated by using an islanded AC microgrid test system built in MATLAB/SimPowerSystems, which indicates that the proposed strategy increases the reliability of system and reduces the controller update times. [ABSTRACT FROM AUTHOR]

Jaguar Land Rover (JLR) has partnered with energy storage start-up Allye Energy to create a Battery Energy Storage System (BESS) using second-life Range Rover and Range Rover Sport PHEV batteries. The BESS can store 270kWh of energy and can charge up to nine Range Rover PHEVs at a time. It can be used to replace diesel generators and provide zero emissions power for off-grid vehicle launches and tests. JLR is investing £15bn into electrification and exploring circular business models for energy storage. The batteries will be recycled at the end of their second-life use. [Extracted from the article]

The article discusses the challenges posed by the intermittency of alternative energy for always-on applications, particularly in the context of mission-critical facilities. Topics include the drawbacks of relying on diesel generators, the benefits of using energy storage systems and distributed energy resources for increased reliability and efficiency, and the potential of microgrids, battery energy storage systems, and fuel cells to provide independent power sources.

The article discusses the importance of engineering professionals in ensuring a successful transition to sustainable energy in the federal sector. It emphasizes the need for practical and economically sound solutions that integrate renewable energy sources into existing infrastructure. The article also highlights the role of emerging technologies, such as microgrids and advanced control systems, in achieving energy resilience. It emphasizes the importance of considering factors like cyber resilience, economic viability, and environmental sustainability in the design and implementation of renewable energy solutions. The article concludes by emphasizing the need for collaboration and innovation in building a sustainable and energy-independent future. [Extracted from the article]

The article discusses how microgrid innovations can enhance power generation at offshore oil and gas facilities, improving supply resilience and reducing carbon emissions. Topics include the growth of the global microgrid market, benefits of microgrids for remote operations, and innovative approaches to self-sustaining power systems in the North Sea.

Microgrids are becoming increasingly important in sustainable power generation as they can help address the intermittent supply issues of solar and wind energy. The recent Bipartisan Infrastructure Law in the US will provide significant investment for grid expansion and modernization, which is crucial for accommodating the transition to lower-carbon energy. Microgrids can handle the extra clean power flowing into big electric grids while new investments in grid modernization take hold. However, there are challenges in expanding transmission networks and interconnecting renewable energy projects, and there is a need for new ways of justifying and distributing costs for grid upgrades. Despite these challenges, microgrids offer opportunities for industries and job creation in supporting sustainable power generation. [Extracted from the article]

This article discusses the challenges faced by Puerto Rico's electrical system in the aftermath of two devastating storms in 2017. The storms exposed the fragility of the island's grid, which was already weakened due to underinvestment in infrastructure and maintenance. The government has since taken action to transform and modernize the electrical infrastructure, but the process will take years and cost billions of dollars. Steps have been taken to diversify energy production and establish renewable energy goals, and the Puerto Rico Energy Bureau has been overseeing the implementation of these policies. The article also mentions upcoming conferences and events related to disaster recovery and resilience in Puerto Rico. [Extracted from the article]

This paper deals with the distributed secondary control problem for multiple distributed generators in an islanded microgrid. A distributed fixed-time secondary controller is designed for each generator using only its neighbors' information, where saturation functions are introduced to the designed controllers to constrain the adverse influence of abnormal data from neighbors. Several indicator variables are introduced to reformulate the saturation function to reduce conservatism. The objective of this paper is to realize the recovery of the frequency and voltage as well as the active power-sharing within a fixed time. The fixed-time convergence of the proposed distributed control algorithm is analyzed through rigorous analysis. Also, the upper bound of the settling time is derived, which does not depend on the system's initial state. Finally, a simulation example is utilized to verify the effectiveness of the proposed distributed control scheme by using the MATLAB/SimPowerSystems toolbox. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to present a new fault detection and classification scheme of both DC faults and AC faults on a DC microgrid network. Design/methodology/approach: To achieve reliable protection, the derivative of DC current signal is decomposed into several intrinsic modes using variational mode decomposition (VMD), which are then used as inputs to the Hilbert–Haung transform technique to obtain the instantaneous amplitude and frequency of the decomposed modes of the signal. A weighted Kurtosis index is used to obtain the most sensitive mode, which is used to compute sudden change in discrete Teager energy (DTE), indicating the occurrence of the fault. A stacked autoencoder-based neural network is applied for classifying the pole to ground (PG), pole to pole (PP), line to ground (LG), line to line (LL) and three-phase line to ground (LLLG) faults. The effectiveness of the proposed protection technique is validated in MATLAB/SIMULINK by considering different test cases. Findings: As the maximum fault detection time is only 5 ms, the proposed detection technique is very fast. A stacked autoencoder-based neural network is applied for classifying the PG, PP, LG, LL and LLLG faults with classification accuracy of 99.1%. Originality/value: The proposed technique provides a very fast, reliable and accurate protection scheme for DC microgrid system. [ABSTRACT FROM AUTHOR]

The article discusses Australia's aim to achieve an resource recovery rate by 2030 and the challenges it faces in reaching this target. It emphasizes the need for urgent and decisive leadership, the introduction of mandated targets for recycled content, and the importance of a national framework to streamline planning processes and ensure uniformity in waste management and recycling efforts across the country.

Developers in the UK are exploring the use of microgrids as an alternative to the National Grid, which is facing a power shortage due to increased electricity consumption and the strain of decarbonization policies and electric vehicle use. Microgrids involve producing and storing electricity from renewable sources locally and distributing it within a development. They offer benefits such as cost reduction, decarbonization, and reduced pressure on the main grid. Microgrids can be connected to the National Grid or operate independently, and they are gaining popularity in the UK. [Extracted from the article]

Chairman Nepra congratulated the company for filing application for licence of micro-grid in the country. National Electric Power Regulatory Authority (Nepra) on Monday decided to grant micro-grid licences to Quaid-e-Azam Solar (Private) Limited (QASPPL) aimed to satisfy the queries raised by Registrar Nepra and Multan Electric Power Company (Mepco). [Extracted from the article]

Wind corridors where the power generation cannot take place as the evacuation capacity of the power is a thorny issue face identical issues. And in the case of the Thar coal, there are talks to bring non-power sector for its usage as cement industry has shifted to coal for production and is currently relying on imported coal. [Extracted from the article]

In this paper, a fast fixed-time vertical plane motion controller is proposed for autonomous underwater gliders (AUGs) gliding in shallow water. The influence of speed-sensorless conditions, model uncertainties, unknown time-varying external disturbances, input saturations, and state delay are taken into account. To improve control performance, a fast fixed-time stable system is first presented. Based on the system, an adaptive extended state observer (ESO) is developed for estimating speed, model uncertainties, and external disturbances. A fast fixed-time controller is designed for improving the gliding efficiency and reducing the risk of hitting the ocean floor. Moreover, an input saturation auxiliary system and an advance compensation method are presented to cope with input saturations and state delay. According to Lyapunov theory, it is proved that the AUG states can converge into a small neighborhood within a fixed time. Finally, simulation results demonstrate the rapidity and effectiveness of the designed control method. [ABSTRACT FROM AUTHOR]

This paper presents a framework structure based on cloud computing for voltage regulation and economic operation of microgrids. Distributed generators (DGs) are controlled through the coordination of a cloud computing layer multi-objective optimization procedure. The cloud computing layer scheduling applies a genetic algorithm aiming at normal voltage operation, minimum cost, and minimum losses, i.e. , achieving the economic operation of DGs while ensuring that the voltage does not cross the limit. The control layer employs a combination of H ∞ and guaranteed cost control to regulate the dynamic performance of DGs and improve system robustness. A ten-bus test system is used to verify the effectiveness of the proposed control strategy. [ABSTRACT FROM AUTHOR]

A recent study conducted at Netaji Subhash Engineering College in Kolkata, India, has developed a student psychology-based optimization (SPBO) tuned proportional-integral derivative accelerator (PIDA) controller to address the frequency regulation issue of an interconnected microgrid system. The proposed control scheme was found to be effective for higher-order system configurations and showed improved responses in terms of peak over/under shoots, oscillations, and settling time compared to available control schemes. The study also presented an improved tie-line model that considers the effect of line resistance along with the line reactance to replicate a practical microgrid scenario. The research was conducted using MATLAB 2016a. [Extracted from the article]

Sumitomo Electric, a Japanese company, has changed its environmental campaign name from "Action ECO" to "Go for Green" in response to the demand for a greener society. The campaign focuses on three core activities: operating for a greener global environment, contributing to the global environment through business, and promoting "Eco-Activities 2030." Sumitomo aims to reduce greenhouse gas emissions, adopt renewable energy, protect biodiversity, and promote environmental preservation activities by 2030. The company is also pursuing top technology and risk management to achieve sustainability and decrease GHG emissions. Additionally, Sumitomo sees opportunities in the expanding market for renewable energy and plans to develop electricity transmission cables and solutions for regional microgrids. [Extracted from the article]

The document titled "BATTERY ENERGY STORAGE SYSTEM" discusses Schneider Electric's battery energy storage system (BESS) as a foundation for an integrated microgrid solution. The BESS is offered in a 20-foot NEMA 3R enclosure and is available in various configurations. It includes battery modules, a battery management system, power conversion unit, and controller. The BESS is fully certified and compliant with fire safety standards and can operate as either grid-connected or off-grid. It has the capacity to store energy for immediate access during outages and can deliver up to 2 MW of power when needed. Services and support are available throughout the product's lifecycle. [Extracted from the article]

A novel distributed secondary voltage and frequency control strategy is proposed with the Zeno-free event-triggered scheme for an island alternating current (AC) microgrid under Denial-of-Service (DoS) attacks. A DoS attack compensation mechanism and an event-triggered mechanism on the basis of the checking scheme are developed. Then, a secure event-checked based event-triggered secondary control method is explored to guarantee the tracking performance of the microgrid under DoS attacks. Further, some linear matrix inequalities (LMIs)-based sufficient conditions are derived to design the controller. What's more, the proposed asynchronous periodic triggering method can efficiently save communication resources and further reduce the update number of the controller. Finally, the efficiency of this work is verified by an islanded AC microgrid with comparisons. [ABSTRACT FROM AUTHOR]

The DC-DC converter severs as one of the crucial components in DC microgrid applications. In this paper, a novel low frequency current-mode control strategy is proposed to improve overshoot suppression performance for the boost converter against load current and source voltage disturbances. The control strategy is presented as a cascade dual-loop structure composed of a dynamic current-loop controller with asymmetric saturation and a PI form voltage-loop controller. With the low frequency information of disturbances, the designed dynamic current-loop controller delivers not only promising disturbance suppression but also superior reference current tracking. Simulation and experiment results are provided to illustrate the superiority of the proposed strategy on overshoot suppression. [ABSTRACT FROM AUTHOR]

The article offers information on using modernizing tactical Military Microgrids to Keep Pace with the electrification of warfare. It discusses that the U.S. Army Futures Command started developing a plan to create electric combat vehicles (ECVs). It addresses the challenges faced by military microgrids.

Purpose: The purpose of this study is toward a better understanding of the interplay between the design and the operation under uncertainties of a simple distributed energy system (DES), by analyzing the sensitivity of the operation strategy over the size of the assets. Design/methodology/approach: A two-step framework is developed in this work: first, the equipment sizes are obtained solving an integrated design approach where an operation strategy Fd is embedded in a design loop; then, once the sizes have been fixed, the DES is evaluated with an operation strategy Fa (which can be the same as Fd). The operation strategies Fd and Fa are not necessarily the same, so the objective of the paper is to study the interplay between the design and the operation by varying the optimality level of the operation strategies in both phases. Findings: The results show that the design of DES cannot be approached without considering its close relationship with the operation strategy. Indeed, the design method needs to be chosen according to the performance of the operation policy finally used in real life: no matter if the operation strategies are the same in both phases but they must lead to a similar level of optimality in terms of operating performance. Originality/value: The originality of this work is to shed light on the importance of the operation strategy in the design procedure as it seems rarely addressed, to the best of the authors' knowledge, in the literature. Indeed, most of the paper dealing with stochastic design of DES solves single large two-stage problems without discussing the way power flows are finally controlled in real life. The optimal design and operation of DES is rarely addressed conjointly, this study aims at bridging the gap between these two isolated scientific communities. [ABSTRACT FROM AUTHOR]

In this article, we present a reinforcement learning-based scheme for secondary frequency control of lossy inverter-based microgrids. Compared with the existing methods in the literature, we relax the common restrictions on the system, i.e., being lossless, and the transmission lines and loads to have known constant impedances. The proposed secondary frequency control scheme does not require a priori information about system parameters and can achieve frequency synchronization within an ultimate bound in the presence of dominantly resistive and/or inductive line and load impedances, model parameter uncertainties, and time varying loads and disturbances. First, using Lyapunov theory, a feedback control is formulated based on the unknown dynamics of the microgrid. Next, a performance function is defined based on cumulative costs toward achieving convergence to the nominal frequency. The performance function is approximated by a critic neural network in real-time. An actor network is then simultaneously learning a parameterized approximation of the nonlinear dynamics and optimizing the approximated performance function obtained from the critic network. Furthermore, using the Lyapunov approach, the uniformly ultimate boundedness of the closed-loop frequency error dynamics and the networks' weight estimation errors are shown. [ABSTRACT FROM AUTHOR]

Before you go for that name brand, consider one of the little guys; you might be surprised just how much better the product's quality is, despite the unknown brand. 3 MOUNTAIN LAUREL DESIGNS Founder Ron Bell had 40 years of lightweight backpacking experience before starting Mountain Laurel Designs (MLD) in 2002. FEATURES Some of the best brands out there for outdoor gear are ones of which most people have never heard. [Extracted from the article]

OGLE COMPONENT DESIGN OCD LOCKRINGS $145 (PAIR) | 14 GRAMS I cannot with a straight face argue for a functional reason why you should purchase these CNC-machined titanium disc-rotor lockrings. ROVAL ALPINIST CLX WHEEL SET $2,650 | 1,250 GRAMS Roval's Alpinist CLX II retains the external rim shape and spoke lacing pattern (21F/24R) of its predecessor but adds tubeless compatibility to this new version. Chris Wehan, Roval's Senior Product Manager, noted that the original Alpinist wheels were planned to be tubeless but, through testing with Roval-sponsored teams, were found to be too light to be run without tubes in the tires. [Extracted from the article]

The article focuses on the U.S. Army's development of an Advanced Medium Mobile Power Sources (AMMPS) microgrid system, which automatically manages generators to meet power demands. Topics include the AMMPS generators' evolution, their optimization for multidomain operations, and the microgrid's applications, including configurations tailored for stationary power, high mobility and support for field hospitals aiming to address sustainment challenges and power gaps in modular medical operations.

The article discusses the development of an innovative microgrid control architecture at Eielson AFB in Alaska. The goal is to provide digital awareness for grid automation to make informed decisions in real time. The article also mentions the need for training on the operation and maintenance of microgrids for U.S. Navy technicians. It highlights the challenges of standardizing microgrid controllers and the importance of collaboration and optimization across different microgrid applications. Additionally, the article mentions the challenge of detecting high impedance faults in utility power distribution systems and the potential risks they pose. [Extracted from the article]

The article explores the significance of microgrids in Australia's energy landscape, particularly in rural and regional areas. It is reported that microgrids, small-scale electricity systems, are gaining traction for their ability to provide reliable and secure energy while incorporating renewable energy sources like solar and wind. It further discusses the challenges and benefits of microgrid deployment.

This paper investigates the event-based fully distributed secondary voltage tracking control problem for direct current (DC) microgrids under denial-of-service (DoS) attacks. Compared with the existing methods, an event-based fully distributed adaptive control scheme is proposed for the secondary control only related to the dynamics of the distributed generator (DG) itself and its neighbors' information, which can achieve the tracking of all DGs without using global information. With DoS attacks consideration, the Zeno behaviors are eliminated by proving that any triggered intervals are positive. In the event-triggered protocols, consecutive communications are not needed for updating the control law and the resources of the communication network can be saved. Finally, an example is used to verify the designed control method validly. [ABSTRACT FROM AUTHOR]

The article explores how tourism companies are looking ways to improve sustainability profile and reduce their environmental footprint. Topics discussed included brief on IMPACT Sustainability Travel & Tourism Conference in Victoria, it discussed the agenda of IMPACT which is presentations of sustainable innovators, whose creations are being applied or can be applied to tourism functions and also mentions companies who have adopted sustainable techniques in their industry.

Steady-state optimization and real-time controls are conventionally achieved by separate controllers acting at different timescales in dc microgrids. The separation between them not only lowers the overall energy efficiency but also can cause the line currents and the output currents of distributed generators (DGs) to exceed their limits. Targeting these issues, an optimal controller for dc microgrids is proposed in this article to simultaneously achieve the real-time minimization of operating losses (converter losses and line losses) and the regulation of line currents and DG output currents. First, the optimization problem is established, then converted to an optimal control problem by a designed penalty function. Thereafter, the necessary and sufficient optimality conditions of the problem are derived, based on which a distributed controller is proposed to dynamically track the optimal operating point. Driven by the proposed optimal controller in real-time, line current and DG output current regulations are ensured with greatly enhanced performance. Finally, the closed-loop system stability is analyzed rigorously through Lyapunov stability synthesis. Simulations based on a switch-level microgrid model validate the performance of the proposed control solution. [ABSTRACT FROM AUTHOR]

The device faults commonly exist in microgrids (MGs) and often undermine the system stability. However, the existing distributed methods generally design control protocols based on the absence of faults or only considering actuator faults, which limits the applicability of controllers in MG systems. Therefore, this paper investigates an adaptive prescribed fixed-time performance (PFTP) consensus fault-tolerant control (FTC) problem for the voltage regulation of a nonlinear islanded MG inverter-based distributed generators (DGs) with output contactor and actuator fault via the state event-triggered mechanism. The PFTP method for the voltage restoration synchronization error is proposed by constructing a novel performance function to increase the speed of voltage recovery. Based on the estimation properties of fuzzy logic system, an unknown nonlinear function and the residual term of output contactor are estimated. Then, an adaptive state event-triggering mechanism is designed to reduce the communication burden, and its main advantage is that the control protocol is updated in the aperiodic way at the triggering instants. Further, according to backstepping technology, a novel adaptive event-triggered consensus FTC protocol is constructed to achieve the voltage regulation of islanded MG, and a parameter adaptive law is designed to compensate the adverse effects of the output contactor fault. Based on the Lyapunov stability theory, it is proved that the voltage recovery synchronization error satisfies the PFTP, and all signals in the closed-loop systems are cooperatively uniformly ultimately bounded. Finally, the proposed control strategy is also validated by using the MATLAB. [ABSTRACT FROM AUTHOR]

The article presents the design of an isolated microgrid for the Base Crestones Shelter in Chirripó National Park. The current electrical system of the shelter does not fully meet its energy needs, which limits the development of new services and increases dependence on fossil fuels. Therefore, the design of a microgrid is proposed, which integrates a micro-hydropower plant, a photovoltaic plant, an energy storage system, and the energy demand of the shelter. A methodology is used that includes diagnosis stages, definition of characteristics, and simulation for the optimal sizing of the microgrid elements. The results show that the design is feasible and meets the required electrical parameters. [Extracted from the article]

The article offers information about the benefits of implementing a microgrid rather than relying on stand-by generators alone include reduced cost of operations and carbon footprint while ensuring an uninterrupted flow of power to maintain business operations. It mentions that built environment requires a constant supply of energy to maintain comfort, safety, security and operations.