Recent Submissions

  • Lessons learned in the use of WIRIS quizzes to upgrade Moodle to solve electrical circuits 

    Bogarra Rodríguez, Santiago; Corbalán Fuertes, Montserrat; Font Piera, Antonio; Plaza, Inma; Arcega Solsona, Francisco Javier (2012-01-16)
    Article
    Open Access
    WIRIS quizzes is an online mathematics tool for educational purposes that upgrades Moodle quizzes, and allows the development of personalized quizzes using random data and conditional instructions. WIRIS quizzes can be ...
  • Study of resonances in 1 x 25 kV AC traction systems 

    Monjo Mur, Lluís; Sainz Sapera, Luis (2015-09-14)
    Article
    Restricted access - publisher's policy
    AC traction systems are 1 x 25 or 2 x 25 kV 50-Hz single-phase, non-linear, time-varying loads that can cause power quality problems. One of the main concerns about these systems is voltage distortion, because adjustable-speed ...
  • Using the instantaneous power of a free acceleration test for squirrel-cage motor parameters estimation 

    Kojooyan, Hengameh; Monjo Mur, Lluís; Córcoles López, Felipe; Pedra Durán, Joaquim (2015-09-01)
    Article
    Open Access
    A new parameters determination method for squirrel-cage induction motors is presented. As a main contribution, the method uses the instantaneous electrical power and the mechanical speed measured in a free acceleration ...
  • Study of resonance in wind parks 

    Monjo Mur, Lluís; Sainz Sapera, Luis; Liang, Jun; Pedra Durán, Joaquim (2015-11-01)
    Article
    Restricted access - publisher's policy
    Wind turbine harmonic current emissions are a well-known power quality problem. These emissions flow through wind park impedances, leading to grid voltage distortion. Parallel resonance may worsen the problem because it ...
  • Parameter estimation of squirrel-cage motors with parasitic torques in the torque–slip curve 

    Monjo Mur, Lluís; Córcoles López, Felipe; Pedra Durán, Joaquim (2015-04-16)
    Article
    Open Access
    This paper studies parasitic torques in steady-state torque–slip curves of squirrel-cage induction motors. The curves of nine motors (small, medium and large size units), three of which were measured in the range s = 2 ...
  • Testing of three-phase equipment under voltage sags 

    Rolán Blanco, Alejandro; Córcoles López, Felipe; Pedra Durán, Joaquim; Monjo Mur, Lluís; Bogarra Rodríguez, Santiago (2015-04-09)
    Article
    Open Access
    This paper provides insight into the testing of three-phase equipment exposed to voltage sags caused by faults. The voltage sag recovers at the fault-current zeros, leading to a ‘discrete’ voltage recovery, that is, the ...
  • Model of aeronautical ground lighting system transformers 

    lomvarte, daniel; Monjo Mur, Lluís; Sainz Sapera, Luis; Pedra Durán, Joaquim (2015-03-02)
    Article
    Open Access
    Airport ground lighting (AGL) systems provide visual reference to aircrafts during airport operations. In AGL systems, constant current regulators feed a beacon circuit supplied through isolation transformers. Component ...
  • Squirrel-cage induction motor parameter estimation using a variable frequency test 

    Monjo Mur, Lluís; Kojooyan, Hengameh; Córcoles López, Felipe; Pedra Durán, Joaquim (2015-06-01)
    Article
    Open Access
    This paper presents amethod for squirrel-cage induction motor parameter estimation using a phase-to-phase standstill variable frequency test. The measured resistance and reactance at different frequencies are the data of ...
  • Iluminación pública con energia eólica y solar 

    Bargalló Perpiñá, Ramón (2015-04-01)
    Article
    Open Access
  • PSpice model of discharge lamps with saturated magnetic ballast and non-square arc voltage 

    Molina, Julio; Sainz Sapera, Luis (2014-09-01)
    Article
    Restricted access - publisher's policy
    High intensity discharge lamps with magnetic ballast are energy-efficient lighting devices commonly used in industrial and public installations. These lamps can be important pollution loads, and their harmonic modeling has ...

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