1,721,190 research outputs found
A Bi-level Approach for the Stochastic Optimal Operation of Interconnected Microgrids
No full textSmart grid planning and control is becoming a theme of high interest in the last years. This is due to the presence of distributed generation, power from renewable resources and storage systems, to the different actors present over the territory, and to the difficulty of defining appropriate models for decision
support. A bilevel optimal control scheme is proposed for grids characterized by renewable and traditional power production, bidirectional power flows, dynamic storage systems, and stochastic modeling issues. In this scheme, the upper level decision maker (UDM) views the lower level decision makers (LDMs) or microgrids as single nodes. In the statement of the UDM problem, the LDM control strategies are structurally and parametrically constrained inside a nonlinear optimization problem that includes load flow equations. Then, the LDMs can follow references from the UDM and use available information at the local level to solve a stochastic optimization problem. The proposed control architecture has been applied to a specific case study (Savona, Italy
A bi-level approach for the optimal control of flows through a network
No full textThe operational management of traffic flows, controlled
by different decision makers (that do not exchange
information) through a network, gives rise to a common modeling
framework that may find application within different research
areas: road traffic control, hazardous materials transportation,
telecommunication networks, energy systems. In this paper, a
general decision architecture is considered and an application is
provided to the case of the management of fleets of vehicles
that transport hazardous materials (hazmat). The considered
architecture takes into account the presence of different decision
makers. The problem is also characterized by the presence
of several (possibly conflicting) objectives. In the case of hazmat
transportation, such objectives may be the reduction of
economic costs and the containment of the risk (for vehicles
and infrastructures). The considered model includes an upperlevel
decision maker that can take decisions affecting the utility
functions of the lower-level decision makers (LDMs), for example,
changing the tolls for the LDMs, but leaving to such LDMs some
decision capability. A specific case study is considered, relevant
to the management of vehicles carrying hazmat through a critical
infrastructure
A decentralized optimal control scheme for route guidance in urban road networks
No full textA feedback decentralized optimal approach for traffic control in urban networks is developed. The control structure is based on the minimization of an objective function corresponding to the difference among the travel times from each origin node to all the possible destination through the available route on the network. The problem solution is provided on a temporal horizon not specified and, generally, each whenever a stochastic event changes the demand function or the infrastructures supply. The adopted methodology foresees the use of three different algorithmic structures; the first one is able to define the dynamics of the transportation system, and has gotten with a macro model of traffic simulation; the seconds is used for esteeming the travel times on the links, using Gallager's algorithm (1977), and the third defines the resolution of a linear problem of optimization subject to nonlinear constrains
Writing Maximum Gap Constraints For Part Routing In Manufacturing Systems Modelled As Petri Nets
No full text- …
