Now showing items 1-17 of 17

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      A method for the sag-tension calculation in electrical overhead lines 

      Albizu Flórez, Igor; Mazón Sainz-Maza, Angel Javier; Fernández Herrero, Elvira (Praise Worthy Prize, 2011-06)
      The sag and tension values of overhead conductors are influenced by the creep developed during the line lifetime. This paper presents a method for the sag-tension calculation of overhead conductors that is characterised ...
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      A Real-Time Sliding Mode Control for a Wind Energy System Based on a Doubly Fed Induction Generator 

      Barambones Caramazana, Oscar; Cortajarena Echeverria, José Antonio; Alkorta Egiguren, Patxi; González de Durana García, José María (MDPI, 2014-10)
      In this paper, a real time sliding mode control scheme for a variable speed wind turbine that incorporates a doubly feed induction generator is described. In this design, the so-called vector control theory is applied, in ...
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      Adaptive Static Line Rating for Systems with HTLS Conductors 

      Albizu Flórez, Igor; Fernández Herrero, Elvira; Alberdi, Rafael; Bedialauneta Landaribar, Miren Terese; Mazón Sainz-Maza, Angel Javier (IEEE, 2018)
      Operation and planning of a power system are constrained by the rating of power lines. Usually, the static line rating is used for system operation and planning. The static line rating defined for an electric grid uses the ...
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      Aspects to take into account in the application of mechanical calculation to high temperature low sag conductors 

      Albizu Flórez, Igor; Mazón Sainz-Maza, Angel Javier; Valverde Santiago, Víctor; Buigues Beraza, Garikoitz (The Institution of Engineering and Technology, 2010-05)
      Reconductoring with high temperature low sag (HTLS) conductors is an alternative to the traditional uprating methods. The obtained rating increase depends on the mechanical and thermal behaviour of the conductor. In this ...
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      Flexible Strain-Tension Calculation Method for Gap-type Overhead Conductors 

      Albizu Flórez, Igor; Mazón Sainz-Maza, Angel Javier; Zamora Belver, Inmaculada (IEEE, 2009-07)
      Commercially available sag-tension programs give good results for most practical applications. However, they have some limitations concerning gap-type conductors. A separate aluminum and core creep calculation is needed ...
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      Forecast Ratio and Security Analysis of Rating Forecasting Methods in an Overhead Line 

      Albizu Flórez, Igor; Fernández Herrero, Elvira; Mazón Sainz-Maza, Angel Javier; Alberdi, Rafael (The Institution of Engineering and Technology, 2017-01-26)
      The actual line rating in overhead lines varies with weather conditions. When a utility defines a rating value for the operation of the line, it takes into account both the security and the forecast ratio. The defined ...
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      Gain Scheduling Control of an Islanded Microgrid Voltage 

      Camblong Ruiz, Aritza; Etxeberria Urkia, Aitor; Ugartemendia de la Iglesia, Juan José; Curea, Octavian (MDPI, 2014-07)
      The aim of this research study has been to design a gain scheduling (GS) digital controller in order to control the voltage of an islanded microgrid in the presence of fast varying loads (FVLs), and to compare it to a ...
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      Influence of Cryogenic Treatment on Wear Resistance and Microstructure of AISI A8 Tool Steel 

      Jimbert Lacha, Pedro José; Iturrondobeitia Ellacuria, Maider; Ibarretxe Uriguen, Julen; Fernández Martínez, Roberto (MDPI, 2018-12)
      The effects of deep cryogenic treatment (DCT) on the wear behavior of different tool steels have been widely reported in the scientific literature with uneven results. Some tool steels show a significant improvement in ...
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      Influence of the conductor temperature error on the overhead line ampacity monitoring systems 

      Albizu Flórez, Igor; Fernández Herrero, Elvira; Mazón Sainz-Maza, Angel Javier; Bengoechea Aresti, Janire (The Institution of Engineering and Technology, 2011-04)
      Many real time overhead line ampacity monitoring systems are based on the calculation of the wind speed. The wind speed is obtained from the conductor temperature. The conductor temperature can be measured directly or it ...
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      Microtab design and implementation on a 5MW wind turbine 

      Fernández Gámiz, Unai; Zulueta Guerrero, Ekaitz; Boyano Murillo, Ana Isabel; Ramos Hernanz, José Antonio; López Guede, José Manuel (MDPI, 2017-05-24)
      Microtabs (MT) consist of a small tab placed on the airfoil surface close to the trailing edge and perpendicular to the surface. A study to find the optimal position to improve airfoil aerodynamic performance is presented. ...
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      Operating Point Optimization of a Hydrogen Fueled Hybrid Solid Oxide Fuel Cell-Steam Turbine (SOFC-ST) Plant 

      Ugartemendia de la Iglesia, Juan José; Ostolaza Zamora, Joseba Xabier; Zubia Olaskoaga, Itziar (MDPI, 2013-09-30)
      This paper presents a hydrogen powered hybrid solid oxide fuel cell-steam turbine (SOFC-ST) system and studies its optimal operating conditions. This type of installation can be very appropriate to complement the intermittent ...
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      Optimized Energy Management Strategy for Wind Plants with Storage in Energy and Reserve Markets 

      González Garrido, Amaia; Villarreal, Igor; Gaztañaga, Haizea; Saez de Ibarra, Andoni; Eguia López, Pablo (IOP Publishing, 2019-05-21)
      This paper addresses the joint operation of wind plants with energy storage systemsin multiple markets to increase the value of wind energy from an economic and technical point of view. The development of an optimized ...
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      Optimizing Biodiesel Production from Waste Cooking Oil Using Genetic Algorithm-Based Support Vector Machines 

      Corral Bobadilla, Marina; Fernández Martínez, Roberto; Lostado Lorza, Rubén; Somovilla Gómez, Fátima; Vergara González, Eliseo P. (MDPI, 2018-11-01)
      The ever increasing fuel demands and the limitations of oil reserves have motivated research of renewable and sustainable energy resources to replace, even partially, fossil fuels, which are having a serious environmental ...
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      Review of dynamic line rating systems for wind power integration 

      Fernández Herrero, Elvira; Albizu Flórez, Igor; Bedialauneta Landaribar, Miren Terese; Mazón Sainz-Maza, Angel Javier; Leite, Patricia T. (Elsevier, 2016-01)
      When a wind power system is connected to a network point there is a limit of power generation based on the characteristics of the network and the loads connected to it. Traditionally, transmission line limits are estimated ...
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      Techniques for On-Line Diagnosis of Stator Shorted Turns in Induction Motors 

      Albizu Flórez, Igor; Zamora Belver, Inmaculada; Mazón Sainz-Maza, Angel Javier; Tapia Otaegui, María Aranzazu (Taylor & Francis, 2006-01)
      In low voltage induction motors, the first indication of a stator fault is the appearance of an inter-turn short circuit. For this reason, several attempts to diagnose reliably these short circuits have been made. Although ...
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      Tension and Ampacity Monitoring System for Overhead Lines 

      Albizu Flórez, Igor; Fernández Herrero, Elvira; Eguía López, Pablo; Torres Iglesias, Esther; Mazón Sainz-Maza, Angel Javier (IEEE, 2013-01-01)
      Real time monitoring allows the determination of the line state and the calculation of the actual rating value. The real time monitoring systems measure sag, conductor tension, conductor temperature or weather related ...
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      Using Genetic Algorithms With Multi-Objective Optimization To Adjust Finite Element Models Of Welded Joints 

      Lostado Lorza, Rubén; Escribano García, Rubén; Fernández Martínez, Roberto; Martínez Calvo, María Ángeles (MDPI, 2018-04-02)
      To ensure realistic results when modeling welded joints using the finite element method (FEM), it is essential to appropriately characterize the thermo-mechanical behavior of the elastic-plastic Finite Element (FE) models. ...