Search results for "Synchro"
showing 10 items of 886 documents
A Cogging Torque Minimization Procedure for Interior Permanent Magnet Synchronous Motors Based on a Progressive Modification of the Rotor Lamination …
2022
This article describes a simple cogging torque minimization procedure for interior permanent magnet synchronous machines (IPMSMs), consisting of a progressive modification of the rotor lamination geometry. This procedure can be generalized for the main topologies of PMSM, independently of the number of stator slots or the location of the permanent magnets. For this purpose, a basic IPMSM structure is analyzed by means of the FEM (finite element method) approach, and then, several other IPMSM geometries, obtained by adequately modifying the rotor lamination geometry of the basic IPMSM model without changing its stator configuration, are proposed and discussed. The trends of the cogging torqu…
Power System Oscillations with Different Prevalence of Grid-Following and Grid-Forming Converters
2022
The oscillatory behaviour of the power system is an aspect that is significantly affected by the increasing integration of converter-based generation sources. Several works address the impact of non-synchronous generation on the operation of the system from different points of view, but only a few studies focus on power-frequency oscillations with a prevalence of generation sources interfaced through power electronics. A lack of research can be found in particular in the comparative analysis of the two main control strategies for power converters, namely grid-following and grid-forming. The article aims to contribute to this direction, starting from a theoretical analysis of the two control…
Analysis a DSP Implementation and Experimental Validation of a Loss Minimization Algorithm Applied to Permanent Magnet Synchronous Motor Drives
2004
In this paper a new loss minimization control algorithm for inverter-fed permanent-magnet synchronous motors (PMSM), which allows to reduce the power losses of the electric drive without penalty on its dynamic performances, is analyzed, experimentally realized and validated. In particular, after a brief recall of two loss minimization control strategies (the "search control" and the "loss-model control"), both a modified dynamic model of the PMSM, which takes into account the iron losses, and a "loss-model" control strategy, are treated. Experimental tests on a specific PMSM drive employing the proposed loss minimization algorithm were performed aiming to validate the actual implementation.…
Stabilization and controller design of 2D discrete switched systems with state delays under asynchronous switching
2013
Published version of a paper from the journal: Abstract and Applied Analysis. Also available from Hindawi:http://dx.doi.org/10.1155/2013/961870. Open Access This paper is concerned with the problem of robust stabilization for a class of uncertain two-dimensional (2D) discrete switched systems with state delays under asynchronous switching. The asynchronous switching here means that the switching instants of the controller experience delays with respect to those of the system. The parameter uncertainties are assumed to be norm-bounded. A state feedback controller is proposed to guarantee the exponential stability. The dwell time approach is utilized for the stability analysis and controller …
Encouraging blended learning and ICT use at Universitat de València to improve the learning process with the .LRN platform
2007
The Universitat de Valencia, one of the largest, oldest and most varied in Spain, concerned about the efficiency of the learning processes in the context of the convergence process towards the Higher Education European Space, has conducted educative innovation experiences in several degrees, diversifying learning activities.Interested in enhancing traditional classroom learning by use of ICT (with progressive blended learning introduction) has established a learning management system to enhance the learning and communication processes for the whole university. The overall goal was to build skills in ICT use in order to improve learning process quality and student participation.This paper de…
Supporting Learning Groups in Online Learning Environment
2015
In this paper, we report on the initial findings on how to effectively support learning groups in online learning environments. Based on the idea that learning groups can enhance effective learning in online learning environments, we used qualitative research methods to study learning groups (interviews and observation of learning group interactions in online learning environments) and their facilitators. Preliminary results reveal that in order to have effective learning groups you need to take care of the following online design issues: develop comprehensive study guides, train online tutors, motivate learners through feedback, and foster high cognitive levels of interaction through quest…
Perceived Sociability and Social Presence in a Collaborative Serious Game
2013
Collaborative serious games have proven to have the potential to support joint knowledge construction, and there is a growing interest in applying such games to promote high-level learning. However, most of the existing studies have focused on the effects of functional, task-specific support while ignoring the social aspects of collaborative learning. This study is one aim to fill in the knowledge gap in order to understand how learners experience educational games as a means of social interaction and collaboration. The findings indicated that the game environment facilitated and supported players’ socio-emotional processes by eliciting students’ social presence and sociability. This has be…
ICT-Supported Education; Learning Styles for Individual Knowledge Building
2010
School surveys and reports on integration of ICT in teaching and learning indicate that the technology is mainly used in traditional learning environments. Furthermore, the most frequently used software in the classrooms are general tools like word processors, presentation tools and Internet browsers. Recent attention among youngsters on social software / web 2.0, contemporary pedagogical approaches like social constructivism and long time experiences with system dynamics and simulations, seem to have a hard time being accepted by teachers and curriculum designers. How can teachers be trained to understand and apply these possibilities optimally that are now available in the classroom and o…
What makes learning and understanding in virtual teams so difficult?
2004
The ideas presented in this article are especially challenged by critical questions raised by the other authors in this special issue. One of the core questions throughout the different studies is whether participants in distributed learning groups are able to successfully work on a common task and achieve a type of interaction that leads them to educationally relevant higher-level discussion and learning. This article discusses the central findings of these studies in light of the recent research on computer-supported collaborative learning. At the beginning of the article, typical problems and challenges related to learning in virtual teams are described. In the end of the discussion, som…
Learning Groups in MOOCs : Lessons for Online Learning in Higher Education
2017
when there is interaction within online learning groups, meaningful learning is achieved. Motivating and sustaining effective student interactions requires planning, coordination and implementation of curriculum, pedagogy and technology. For our aim to understand online learning group processes to identify effective online learning group mechanisms, comparative analysis was used on a massive open online course (MOOC) run in 2015 and 2016. Qualitative (interaction on the platform) and quantitative (survey) methods were used. The findings revealed several possible ways to improve online learning group processes. This paper concludes that course organization helped in increasing individual par…