7,156 research outputs found
Mean Field Game-Based Control of Dispersed Energy Storage Devices with Constrained Inputs
RÉSUMÉ Avec plus de production d’énergie renouvelable (éoliennes, panneaux solaires) connectés au réseau électrique, il devient important d’équilibrer la
charge et la production alors que la variabilité est un problème pour les ressources renouvelables. On a étudié les dispositifs de stockage d’énergie, en particulier ceux qui sont naturellement présents au réseau électrique
(tels que les chauffe-eau électriques, les chauffages électriques, etc. dans les ménages) pourraient devenir des sources potentielles pour atténuer ce problème de variabilité. Afin de minimiser le besoin de communication et les efforts de calcul, un mécanisme de contrôle décentralisé est développé dans cette recherche
pour contrôler la trajectoire de champ moyen d’une grande population de chauffages électriques pour suivre (ou atteindre) une cible de température. Le contrôle optimal pour chaque chauffage ou joueur est localement calculé
et respecte certaines contraintes. Le problème de contrôle est formulé comme un problème de commande linéaire quadratique (LQ) avec des entrées contraintes dans la théorie du jeu de champ moyen, en anglais, Mean
Field Game (MFG). Le mécanisme de contrôle décentralisé est développé à partir de la solution d’équilibre du modèle, cette dernière est obtenue lorsque chaque joueur individuel choisit la meilleure réponse au champ moyen basé sur l’état global de la population. En choisissant les stratégies
optimales, tous les joueurs reproduisissent collectivement le champ moyen de la population. En ce sens, la solution d’équilibre est un point fixe du système. Dans une configuration de MFG, les joueurs sont faiblement couplés,
ce qui signifie qu’un joueur a une influence négligeable sur le système global tandis que le comportement de la population entière a un effet significatif sur chaque joueur individuel.----------ABSTRACT With the increasing levels of renewable power generation (wind turbines,
solar panels) connected to power grids, it is becoming important to balance the load and the generation while variability issue exists for renewable resources. It has been studied that energy storage devices, in particular
those naturally present in the power system (such as electric water heaters, electric space heaters, etc. in households), can become potential sources to help mitigate such variability. In order to minimize the communication bandwidth and computation efforts, a decentralized control mechanism is developed in this research to shape the aggregate load profile of a large population of electric space heaters in a power system. Under the control mechanism, the mean-field trajectory (temperature) of the load population is controlled to follow a target
temperature, and the control input for each device is generated locally and must respect certain constraint. We formulate the problem as a linear quadratic (LQ) tracking problem with constrained inputs under the mean
field game (MFG) settings. The decentralized mechanism is then derived based on the equilibrium solution to the formulated model. The equilibrium solution is obtained when each individual agent of the game chooses a best response to the so-called mass effect of the population via couplings
of their individual dynamics and cost functions; when all agents choose the optimal strategies, collectively the mass effect should be replicated. In this sense, the equilibrium solution is a fixed point of the system, and can be
mathematically characterized by a mean-field (MF) fixed point equation system. In such MFG setup, agents are weakly coupled, meaning that an agent has a negligible influence on the overall system while the mean-field
behavior of the population has a significant effect on any individual agent
Mean-Field-Type Games in Engineering
A mean-field-type game is a game in which the instantaneous payoffs and/or
the state dynamics functions involve not only the state and the action profile
but also the joint distributions of state-action pairs. This article presents
some engineering applications of mean-field-type games including road traffic
networks, multi-level building evacuation, millimeter wave wireless
communications, distributed power networks, virus spread over networks, virtual
machine resource management in cloud networks, synchronization of oscillators,
energy-efficient buildings, online meeting and mobile crowdsensing.Comment: 84 pages, 24 figures, 183 references. to appear in AIMS 201
Local Water Storage Control for the Developing World
Most cities in India do not have water distribution networks that provide
water throughout the entire day. As a result, it is common for homes and
apartment buildings to utilize water storage systems that are filled during a
small window of time in the day when the water distribution network is active.
However, these water storage systems do not have disinfection capabilities, and
so long durations of storage (i.e., as few as four days) of the same water
leads to substantial increases in the amount of bacteria and viruses in that
water. This paper considers the stochastic control problem of deciding how much
water to store each day in the system, as well as deciding when to completely
empty the water system, in order to tradeoff: the financial costs of the water,
the health costs implicit in long durations of storing the same water, the
potential for a shortfall in the quantity of stored versus demanded water, and
water wastage from emptying the system. To solve this problem, we develop a new
Binary Dynamic Search (BiDS) algorithm that is able to use binary search in one
dimension to compute the value function of stochastic optimal control problems
with controlled resets to a single state and with constraints on the maximum
time span in between resets of the system
Energy Aware Algorithms for managing Wireless Sensor Networks
While the majority of the current Wireless Sensor Networks (WSNs) research has prioritized either the coverage of the monitored area or the energy efficiency of the network, it is clear that their relationship must be further studied in order to find optimal solutions that balance the two factors. Higher degrees of redundancy can be attained by increasing the number of active sensors monitoring a given area which results in better performance. However, this in turn increases the energy being consumed. In our research, we focus on attaining a solution that considers several optimization parameters such as the percentage of coverage, quality of coverage and energy consumption. The problem is modeled using a bipartite graph and employs an evolutionary algorithm to handle the activation and deactivation of the sensors. An accelerated version of the algorithm is also presented; this algorithm attempts to cleverly mutate the string being considered after analyzing the desired output conditions and performs a calculated crossover depending on the fitness of the parent strings. This results in a quicker convergence and a considerable reduction in the search time for attaining the desired solutions. Proficient cluster formation in wireless sensor networks reduces the total energy consumed by the network and prolongs the life of the network. There are various clustering approaches proposed, depending on the application and the objective to be attained. There are situations in which sensors are randomly dispersed over the area to be monitored. In our research, we also propose a solution for such scenarios using heterogeneous networks where a network has to self-organize itself depending on the physical allocations of sensors, cluster heads etc. The problem is modeled using a multi-stage graph and employs combinatorial algorithms to determine which cluster head a particular sensor would report to and which sink node a cluster head would report to. The solution proposed provides flexibility so that it can be applied to any network irrespective of density of resources deployed in the network. Finally we try to analyze how the modification of the sequence of execution of the two methods modifies the results. We also attempt to diagnose the reasons responsible for it and conclude by highlighting the advantages of each of the sequence
Enhancing Cyber-Resiliency of DER-based SmartGrid: A Survey
The rapid development of information and communications technology has
enabled the use of digital-controlled and software-driven distributed energy
resources (DERs) to improve the flexibility and efficiency of power supply, and
support grid operations. However, this evolution also exposes
geographically-dispersed DERs to cyber threats, including hardware and software
vulnerabilities, communication issues, and personnel errors, etc. Therefore,
enhancing the cyber-resiliency of DER-based smart grid - the ability to survive
successful cyber intrusions - is becoming increasingly vital and has garnered
significant attention from both industry and academia. In this survey, we aim
to provide a systematical and comprehensive review regarding the
cyber-resiliency enhancement (CRE) of DER-based smart grid. Firstly, an
integrated threat modeling method is tailored for the hierarchical DER-based
smart grid with special emphasis on vulnerability identification and impact
analysis. Then, the defense-in-depth strategies encompassing prevention,
detection, mitigation, and recovery are comprehensively surveyed,
systematically classified, and rigorously compared. A CRE framework is
subsequently proposed to incorporate the five key resiliency enablers. Finally,
challenges and future directions are discussed in details. The overall aim of
this survey is to demonstrate the development trend of CRE methods and motivate
further efforts to improve the cyber-resiliency of DER-based smart grid.Comment: Submitted to IEEE Transactions on Smart Grid for Publication
Consideratio
The Role of Deep Learning in Advancing Proactive Cybersecurity Measures for Smart Grid Networks: A Survey
As smart grids (SG) increasingly rely on advanced technologies like sensors
and communication systems for efficient energy generation, distribution, and
consumption, they become enticing targets for sophisticated cyberattacks. These
evolving threats demand robust security measures to maintain the stability and
resilience of modern energy systems. While extensive research has been
conducted, a comprehensive exploration of proactive cyber defense strategies
utilizing Deep Learning (DL) in {SG} remains scarce in the literature. This
survey bridges this gap, studying the latest DL techniques for proactive cyber
defense. The survey begins with an overview of related works and our distinct
contributions, followed by an examination of SG infrastructure. Next, we
classify various cyber defense techniques into reactive and proactive
categories. A significant focus is placed on DL-enabled proactive defenses,
where we provide a comprehensive taxonomy of DL approaches, highlighting their
roles and relevance in the proactive security of SG. Subsequently, we analyze
the most significant DL-based methods currently in use. Further, we explore
Moving Target Defense, a proactive defense strategy, and its interactions with
DL methodologies. We then provide an overview of benchmark datasets used in
this domain to substantiate the discourse.{ This is followed by a critical
discussion on their practical implications and broader impact on cybersecurity
in Smart Grids.} The survey finally lists the challenges associated with
deploying DL-based security systems within SG, followed by an outlook on future
developments in this key field.Comment: To appear in the IEEE internet of Things journa
Thirty Years of Machine Learning: The Road to Pareto-Optimal Wireless Networks
Future wireless networks have a substantial potential in terms of supporting
a broad range of complex compelling applications both in military and civilian
fields, where the users are able to enjoy high-rate, low-latency, low-cost and
reliable information services. Achieving this ambitious goal requires new radio
techniques for adaptive learning and intelligent decision making because of the
complex heterogeneous nature of the network structures and wireless services.
Machine learning (ML) algorithms have great success in supporting big data
analytics, efficient parameter estimation and interactive decision making.
Hence, in this article, we review the thirty-year history of ML by elaborating
on supervised learning, unsupervised learning, reinforcement learning and deep
learning. Furthermore, we investigate their employment in the compelling
applications of wireless networks, including heterogeneous networks (HetNets),
cognitive radios (CR), Internet of things (IoT), machine to machine networks
(M2M), and so on. This article aims for assisting the readers in clarifying the
motivation and methodology of the various ML algorithms, so as to invoke them
for hitherto unexplored services as well as scenarios of future wireless
networks.Comment: 46 pages, 22 fig
Control and Optimization of Energy Storage in AC and DC Power Grids
Energy storage attracts attention nowadays due to the critical role it will play in the power generation and transportation sectors. Electric vehicles, as moving energy storage, are going to play a key role in the terrestrial transportation sector and help reduce greenhouse emissions. Bulk hybrid energy storage will play another critical role for feeding the new types of pulsed loads on ship power systems. However, to ensure the successful adoption of energy storage, there is a need to control and optimize the charging/discharging process, taking into consideration the customer preferences and the technical aspects. In this dissertation, novel control and optimization algorithms are developed and presented to address the various challenges that arise with the adoption of energy storage in the electricity and transportation sectors.
Different decentralized control algorithms are proposed to manage the charging of a mass number of electric vehicles connected to different points of charging in the power distribution system. The different algorithms successfully satisfy the preferences of the customers without negatively impacting the technical constraints of the power grid. The developed algorithms were experimentally verified at the Energy Systems Research Laboratory at FIU. In addition to the charge control of electric vehicles, the optimal allocation and sizing of commercial parking lots are considered. A bi-layer Pareto multi-objective optimization problem is formulated to optimally allocate and size a commercial parking lot. The optimization formulation tries to maximize the profits of the parking lot investor, as well as minimize the losses and voltage deviations for the distribution system operator. Sensitivity analysis to show the effect of the different objectives on the selection of the optimal size and location is also performed. Furthermore, in this dissertation, energy management strategies of the onboard hybrid energy storage for a medium voltage direct current (MVDC) ship power system are developed. The objectives of the management strategies were to maintain the voltage of the MVDC bus, ensure proper power sharing, and ensure proper use of resources, where supercapacitors are used during the transient periods and batteries are used during the steady state periods. The management strategies were successfully validated through hardware in the loop simulation
Self-Evaluation Applied Mathematics 2003-2008 University of Twente
This report contains the self-study for the research assessment of the Department of Applied Mathematics (AM) of the Faculty of Electrical Engineering, Mathematics and Computer Science (EEMCS) at the University of Twente (UT). The report provides the information for the Research Assessment Committee for Applied Mathematics, dealing with mathematical sciences at the three universities of technology in the Netherlands. It describes the state of affairs pertaining to the period 1 January 2003 to 31 December 2008
- …