Documentos de Trabajo: Envíos recientes
Mostrando ítems 521-540 de 1898
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Dimensioning of DC traction substations with realistic traffic scenarios
The study of energy consumption is fundamental for railway systems in general and for DC electrified railway systems in particular. It plays an important role in order to design a proper dimensioning of traction Substations ... -
LTCL-Filter active-damping design considerations for low-switching-frequency grid-tied VSCs
Most electronic devices are connected to the grid by using power electronics converters and, in order to reduce the filter size and cost, novel filter topologies are being proposed in the literature. For high-power ... -
Methodology for managing traceability in the measurement of torque in wind generators
The research described within this paper has aimed to develop new methods for determining torque in an accurate, traceable way. The proposed methods must suit the operating conditions on nacelle test benches, which are ... -
A stochastic market-clearing model using semidefinite relaxation
This paper proposes a two-stage stochastic market clearing (SMC) model based on a semidefinite programming (SDP) relaxation. The SMC model aims at determining the day-ahead schedule (DA) and the real-time (RT) balance ... -
PMU-based estimation of the frequency of the center of inertia and generator rotor speeds
The paper compares a variety of on-line approaches based on PMUs to estimate the angular speed of individual synchronous machines as well as of the center of inertia. These approaches involve the solution of an optimization ... -
Wide area controllers for excitation boosters for transient stability improvement
Excitation boosters (EBs) are one of the most costeffective solutions to improve Fault Ride Through (FRT) capability of synchronous generators. However, they may lead to undesired behavior in multi-machine systems when ... -
Experiences developing large-scale synthetic U.S.-style distribution test systems
This paper describes computational, data management, and other experiences developing large-scale, realistic-but-not-real U.S.-style distribution test systems for the Smart-DS project. These test systems cover entire ... -
A comparative study of the application of lesson study in different university learning environments
This paper presents the application of Lesson Study technique to seven subjects in different faculties in three Spanish universities. Lesson study is a methodology for the improvement of any teaching activity based on the ... -
Impact of PLL control on small-signal stability of wind DFIGs
This paper investigates the small-signal stability of wind doubly fed induction generators. Precisely, the impact of the phase locked loop control on the small-signal stability of wind doubly fed induction generators is ... -
Show me the money! Energy storage systems between the technically feasible and the economically viable
Due to the recommendations of the IPCC Global Warming report [ 1 ], CO2 emissions have to be halved by 2030 in order to avoid devastating changes to our climate. The 2030 climate and energy framework [ 2 ] that was adopted ... -
Sensitivities and uncertainties of eco-driving algorithm estimating train power consumption
This paper describes a study of uncertainty propagation through the Train Simulator Algorithm (TSA). The algorithm is used to estimate train driving time, consumed and regenerated energy. These output quantities are important ... -
MPP awareness in Automatic Generation Control (AGC) with wind farm participation
The AGC is a system that automatically controls the generation of power plants participating in secondary frequency regulation [1]. Currently common AGC systems are designed to control conventional power plants such as ... -
A simple rule-based energy management system for off-grid systems
Off-grid systems are systems that are not interconnected with the grid and that congruently operate in islanded mode permanently. In order to operate the off-grid system efficiently, an energy management system (EMS) is ... -
Impact of the q-axis sub-transient reactance on the rotor oscillations of a hydro generator
In the process of refurbishing a hydro generator, the owner has requested manufacturers to supply a machine that exhibits the same electrical parameters than the old one. The selected supplier has informed that such ... -
Highly sensitive dielectric resonator sensor for liquid characterization
This article describes a novel 2 GHz dielectric resonator sensor (DRS). The dielectric resonator is made of ceramic material and is fed by a microstrip transmission line, using the aperture-feeding method. The sensor shows ... -
Wind generation in weak systems
Control systems of wind generators are usually designed neglecting the effect of the external grid (the impedance of the grid is much smaller than the impedance of the step-up transformers). Wind generator manufacturers ... -
Islanding tests in medium voltage distribution systems with synchronous and non-synchronous generation
The increasing penetration of distributed generation is leading to a higher number of unintentional islands in distribution grids. Currently, islanded operation of distribution grids is not allowed, since it poses a threat ... -
Closed-loop two-stage stochastic optimization of offshore wind farm collection system
A two-stage stochastic optimization model for the design of the closed-loop cable layout of an Offshore Wind Farm (OWF) is presented. The model consists on a Mixed Integer Linear Program (MILP) with scenario numeration ... -
Web applications for PLC simulations: first steps towards PLC simulations-as-a-service
PLC (Power Line Communications) present a wide range of advantages that make them very appropriate for Smart Grid applications, such as that there is no need to deploy additional communication infrastructure. However, they ... -
Influence of PLL parameters on small-signal stability of microgrids with synchronous generators
Hybrid microgrids (MGs) with both renewable energy sources (RESs) and diesel-generator sets are used to guarantee the continuity of power supply in remote areas with no access to electricity networks. RESs are commonly ...