Search results for "model [interaction]"
showing 10 items of 1495 documents
Dynamic performance enhancement of AC/DC PFC boost converters by means of MRAS observers
2015
Controlling a Power Factor Corrected (PFC) boost converter is not a trivial task, because the higher the dynamic performance, the higher is the input current distortion. On the other hand, recent applications of these converters require fast transients in response to disturbances, such as sudden variations of load power, reference voltage and input voltage. Better performance can be obtained adding a feedforward action to the traditional control scheme, using observers to estimate the input voltage and the output current. However, the actual improvement depends on the dynamic performance of the chosen observers. This paper aims at evaluating the applicability and the performance of differen…
Measurement-based load modelling for power supply system design
2008
Load modelling is essential to simulate system features as closely as possible to the effective behaviour. In spite of model complexity, the need for accuracy often leads to a component-based approach, i.e. the analysis of load internal subsystems. It is a common belief that measurement-based load models lead to low accuracy. This paper presents a new, high-accuracy measurement-based load modelling approach to define a power consumption profile load model for power systems design. The load modeling technique is described by an application. Simulation and experimental results are compared. The efficiency and portability of the proposed modelling approach is discussed. ©2008 IEEE.
A structured filter for Markovian switching systems
2014
In this work, a new methodology for the structuring of multiple model estimation schemas is developed. The proposed filter is applied to the estimation and detection of active mode in dynamic systems. The discrete-time Markovian switching systems represented by several linear models, associated with a particular operating mode, are studied. Therefore, the main idea of this work is the subdivision of the models set to some subsets in order to improve the detection and estimation performances. Each subset is associated with sub-estimators based on models of the subset. In order to compute the global estimate and subset probabilities, a global estimator is proposed. Theoretical developments ba…
Identification and robust control of DC/DC converter Hammerstein model
2008
Abstract—This paper deals with model-based robust control of dc/dc power electronic converters. The converter is described by means of a Hammerstein model consisting of the nonlinear static characteristics of the converter and a linear time-invariant (LTI) uncertainmodel whose parameters depend on the actual duty-cycle operating range. This suggests that the controller be designed using robust control techniques. In view of applying robust control, identification of the earlier LTI models is performed by means of simulation experiments, carried out on a converter switching model implemented onMATLAB/SIMULINK environment. Internal model control (IMC) structure is employed for the controller …
Algorithmic method of design and analysis of fractional-slot windings of AC machines
1998
The paper presents a new algorithmic method of designing fractional-slot windings for AC machines of the double and single layer type. The method allows to design windings with a small number of slots per pole and phase, and then to analyse their MMF harmonic spectra in a simple systematic way and to optimise the construction. The presented method comprises not only 3-phase, but alsom-phase windings, which in the case of compact converter-motor units are quite applicable.
COMPARATIVE ANALYSIS OF RIGID AND FLEXIBLE STRUCTURES OF THE ECCENTRIC PRESSES
2007
Abstract The aim of this paper is to make a comparative study of the static behaviour of the eccentric presses, using the finite elements method, on the rigid structure and on the flexible structure, respectively. The finite elements modelling of the component elements of the presses are done in two ways: node by node link type (rigid structure) or using a linking element spring damper type (flexible structure). On these two structures there is successively applied a number of static analyses, in order to determine the strain of working area and the design of the stiffness graph.
Hammerstein Model-Based Robust Control of DC/DC Converters
2007
This paper deals with model-based robust control of DC/DC power electronic converters. The converter is modelled by means of its static characteristic and a few continuous-time linear and time-invariant (LTI) models corresponding to contiguous ranges of duty-cycle. The model appears as a Hammerstein model in which the values of the parameters of the LTI part depend on the actual duty-cycle operating range. This suggests to describe the converter as an uncertain system to be controlled using robust control techniques. Frequency domain approach is used for describing the nominal model and the uncertainty. In view of applying robust control, identification of the LTI models is performed by mea…
Can business model innovation help SMEs in the food and beverage industry to respond to crises? Findings from a Swiss brewery during COVID-19
2021
PurposeThe purpose of this paper is to show how different business model innovations (BMIs) help small and medium-sized enterprises (SMEs) in the food and beverage industry to navigate turbulent and uncertain environments such as the coronavirus economic crisis (COVID-19).Design/methodology/approachThe paper adopts an in-depth case study approach and uses a dynamic business modeling (DBM) approach to analyze how a pioneer craft brewery in Switzerland implemented innovative actions undertaken during the COVID-19 pandemic.FindingsThe paper offers a novel framework describing three processes helping SMEs to implement innovations in their business model (BM) to respond in an effective way to cr…
Entrepreneurship and Resilience in Spanish Sports Clubs: A Cluster Analysis.
2021
Entrepreneurial orientation can be an effective response by sports clubs to manage a recession, such as the COVID-19 crisis. Therefore, its study can be fundamental to understand different ways of managing a recession. This study analyzes the entrepreneurial orientation of Spanish non-profit sports clubs to identify different groups and their profiles. The sample is composed of 145 Spanish non-profit sports clubs. Different validated scales have been used to analyze entrepreneurial orientation, business model adaptation, service quality, and economic and social performance (performance in social impact and performance in social causes). Entrepreneurial orientation is the variable used to di…
Green entrepreneurship and SME performance: the moderating effect of firm age
2021
AbstractGreen entrepreneurship has been increasing with growing attention to environment protection by a variety of stakeholders. Green innovation, as the essence of green entrepreneurship, has attracted a broad range of scholarly attention with yet inconclusive findings regarding its effect on firm performance. According to our analyses of 1667 firms listed on SME board and GEM in China during the period from 2010 to 2019, we find interesting results regarding the type of green innovation involved and the moderating effect of firm age on the link between green innovation and SME performance. More precisely, we find green utility-model innovation positively influences firm performance for S…