781 research outputs found
Competitive Charging Station Pricing for Plug-in Electric Vehicles
This paper considers the problem of charging station pricing and plug-in
electric vehicles (PEVs) station selection. When a PEV needs to be charged, it
selects a charging station by considering the charging prices, waiting times,
and travel distances. Each charging station optimizes its charging price based
on the prediction of the PEVs' charging station selection decisions and the
other station's pricing decision, in order to maximize its profit. To obtain
insights of such a highly coupled system, we consider a one-dimensional system
with two competing charging stations and Poisson arriving PEVs. We propose a
multi-leader-multi-follower Stackelberg game model, in which the charging
stations (leaders) announce their charging prices in Stage I, and the PEVs
(followers) make their charging station selections in Stage II. We show that
there always exists a unique charging station selection equilibrium in Stage
II, and such equilibrium depends on the charging stations' service capacities
and the price difference between them. We then characterize the sufficient
conditions for the existence and uniqueness of the pricing equilibrium in Stage
I. We also develop a low complexity algorithm that efficiently computes the
pricing equilibrium and the subgame perfect equilibrium of the two-stage
Stackelberg game.Comment: 15 pages, 21 figure
Integration of Massive Plug-in Hybrid Electric Vehicles into Power Distribution Systems: Modeling, Optimization, and Impact Analysis
With the development of vehicle-to-grid (V2G) technology, it is highly promising to use plug-in hybrid electric vehicles (PHEVs) as a new form of distributed energy resources. However, the uncertainties in the power market and the conflicts among different stakeholders make the integration of PHEVs a highly challenging task. Moreover, the integration of PHEVs may lead to negative effects on the power grid performance if the PHEV fleets are not properly managed.
This dissertation studies various aspects of the integration of PHEVs into power distribution systems, including the PHEV load demand modeling, smart charging algorithms, frequency regulation, reliability-differentiated service, charging navigation, and adequacy assessment of power distribution systems. This dissertation presents a comprehensive methodology for modeling the load demand of PHEVs. Based on this stochastic model of PHEV, a two-layer evolution strategy particle swarm optimization (ESPSO) algorithm is proposed to integrate PHEVs into a residential distribution grid. This dissertation also develops an innovative load frequency control system, and proposes a hierarchical game framework for PHEVs to optimize their charging process and participate in frequency regulation simultaneously. The potential of using PHEVs to enable reliability-differentiated service in residential distribution grids has been investigated in this dissertation. Further, an integrated electric vehicle (EV) charging navigation framework has been proposed in this dissertation which takes into consideration the impacts from both the power system and transportation system. Finally, this dissertation proposes a comprehensive framework for adequacy evaluation of power distribution networks with PHEVs penetration.
This dissertation provides innovative, viable business models for enabling the integration of massive PHEVs into the power grid. It helps evolve the current power grid into a more reliable and efficient system
JMT – Performance Engineering Tools for System Modeling
We present the Java Modelling Tools (JMT) suite, an integrated
framework of Java tools for performance evaluation of computer
systems using queueing models. The suite offers a rich user interface that simplifies the definition of performance models by means of wizard dialogs and of a graphical design workspace.
The performance evaluation features of JMT span a wide range
of state-of-the-art methodologies including discrete-event simulation, mean value analysis of product-form networks, analytical identification of bottleneck resources in multiclass environments, and workload characterization with fuzzy clustering. The discrete-event simulator supports several advanced modeling features such as finite capacity regions, load-dependent service times, bursty processes, fork-and-join nodes, and implements spectral estimation for analysis of simulative results. The suite is open-source, released under the GNU general public license (GPL), and it is available for
free download at http://jmt.sourceforge.net
Performance-oriented Cloud Provisioning: Taxonomy and Survey
Cloud computing is being viewed as the technology of today and the future.
Through this paradigm, the customers gain access to shared computing resources
located in remote data centers that are hosted by cloud providers (CP). This
technology allows for provisioning of various resources such as virtual
machines (VM), physical machines, processors, memory, network, storage and
software as per the needs of customers. Application providers (AP), who are
customers of the CP, deploy applications on the cloud infrastructure and then
these applications are used by the end-users. To meet the fluctuating
application workload demands, dynamic provisioning is essential and this
article provides a detailed literature survey of dynamic provisioning within
cloud systems with focus on application performance. The well-known types of
provisioning and the associated problems are clearly and pictorially explained
and the provisioning terminology is clarified. A very detailed and general
cloud provisioning classification is presented, which views provisioning from
different perspectives, aiding in understanding the process inside-out. Cloud
dynamic provisioning is explained by considering resources, stakeholders,
techniques, technologies, algorithms, problems, goals and more.Comment: 14 pages, 3 figures, 3 table
Location analysis of electric vehicle charging stations for maximum capacity and coverage
Electric vehicle charging facility location is a critical component of long-term strategic planning. Integration of electric vehicles into mainstream adoption has unique characteristics as it requires a careful investigation of both electric and transportation networks. In this paper, we provide an overview of recent approaches in location analyses of electric vehicle charging infrastructures. We review approaches from classical operations research for fast and slow charging stations. Sample formulations along with case studies are presented to provide insights. We discuss that classical methods are appropriate to address the coverage of charging networks which is defined as average time or distance to reach a charging station when needed. On the other hand, calculating required capacity, defined as the individual charging resources at each node, is still an open research topic. In the final part, we present stochastic facility location theory that uses queuing and other probabilistic approaches
Queueing Networks for Vertical Handover
PhDIt is widely expected that next-generation wireless communication systems will be
heterogeneous, integrating a wide variety of wireless access networks. Of particular
interest recently is a mix of cellular networks (GSM/GPRS and WCDMA) and
wireless local area networks (WLANs) to provide complementary features in terms
of coverage, capacity and mobility support. If cellular/ WLAN interworking is to be
the basis for a heterogeneous network then the analysis of complex handover traffic
rates in the system (especially vertical handover) is one of the most essential issues to
be considered.
This thesis describes the application of queueing-network theory to the modelling of
this heterogeneous wireless overlay system. A network of queues (or queueing
network) is a powerful mathematical tool in the performance evaluation of many
large-scale engineering systems. It has been used in the modelling of hierarchically
structured cellular wireless networks with much success, including queueing
network modelling in the study of cellular/ WLAN interworking systems. In the
process of queueing network modelling, obtaining the network topology of a system
is usually the first step in the construction of a good model, but this topology
analysis has never before been used in the handover traffic study in heterogeneous
overlay wireless networks. In this thesis, a new topology scheme to facilitate the
analysis of handover traffic is proposed.
The structural similarity between hierarchical cellular structure and heterogeneous
wireless overlay networks is also compared. By replacing the microcells with
WLANs in a hierarchical structure, the interworking system is modelled as an open
network of Erlang loss systems and with the new topology, the performance
measures of blocking probabilities and dropping probabilities can be determined.
Both homogeneous and non-homogeneous traffic have been considered, circuit
switched and packet-switched. Example scenarios have been used to validate the
models, the numerical results showing clear agreement with the known validation
scenarios
- …