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Full-Text Articles in Engineering
Solar Photovoltaic System Control Topology Investigation For Power Source Mismatch, Lynette O'Callaghan
Solar Photovoltaic System Control Topology Investigation For Power Source Mismatch, Lynette O'Callaghan
Conference papers
An investigation into solar photovoltaic (PV) system control topology selection, when partial shade is anticipated in the solar array, is presented. As available area is maximised in Building Integrated PV (BIPV) systems, shading is an inevitable consequence. The presence of partial shading in a PV array leads to multiple power peaks in the power-voltage curve, due to bypass diode sections being triggered, and an increase in module mismatch losses in the array. A building energy design software, Integrated Environmental Solutions, is used to determine the shadowed area on PV modules throughout the year, incorporating the PV system location and geometrical …
Three-Level Hysteresis Current Control Strategy For Three-Phase Four-Switch Shunt Active Filters, Samet Biricik, Hasan Komurcugil
Three-Level Hysteresis Current Control Strategy For Three-Phase Four-Switch Shunt Active Filters, Samet Biricik, Hasan Komurcugil
Articles
In this study, a three-level hysteresis current-control (HCC) strategy is proposed for three-phase four-switch shunt active power filters. The four-switch topology which utilises four switching devices together with two series connected capacitors is able to reduce the cost, switching losses and improve the reliability of system. In this topology, when the current control of phases A and B is achieved successfully, the current control of phase C which is connected to the midpoint of the series connected capacitors is achieved automatically. The current control is achieved by using a three-level HCC strategy. An important consequence of using this control strategy …
Investigation To Improve The Control And Operation Of A Three-Phase Photovoltaic Grid-Tie Inverter, Mohamed Moin Hanif
Investigation To Improve The Control And Operation Of A Three-Phase Photovoltaic Grid-Tie Inverter, Mohamed Moin Hanif
Doctoral
Solar Energy or more precisely photovoltaic energy is one of the most promising sources of electricity for the future and it can be used as a distributed generator (DG) to play its role in ‘smart grids of the future’. Distributed PV (photovoltaic) generators can provide numerous potential benefits such as augmenting the capacity of distribution systems, deferring capital investments on distribution and transmission (T&D) systems and improving power quality and system reliability. The PV energy which possesses very special I-V and P-V characteristics has to be conditioned by a PV inverter before it can be consumed by an ac load …
Online Real-Time Water Quality Monitoring And Control System, Paul Duffy, Gerard Woods, James Walsh, Michael Kane
Online Real-Time Water Quality Monitoring And Control System, Paul Duffy, Gerard Woods, James Walsh, Michael Kane
Conference Papers
No abstract provided.
On-Line Realtime Water Quality Monitoring And Control For Swimming Pools, Paul Duffy, Gerard Woods, Sean O'Hogain, James Walsh, C. Caplier
On-Line Realtime Water Quality Monitoring And Control For Swimming Pools, Paul Duffy, Gerard Woods, Sean O'Hogain, James Walsh, C. Caplier
Conference Papers
Effective swimming pool water quality monitoring and control systems are important to safeguard public health and for bather comfort. Most Irish swimming pool monitoring systems rely heavily on manual methods for sampling, testing and data recording of important parameters. Microbiological testing is infrequent and results can often take days. The goal of this research is to develop a water quality monitoring and control system with real time data logging, automatic data analysis, remote monitoring and control, microbiological sampling capabilities and online connectivity. National Instruments hardware and its software package LabView form the basis of the monitoring and control system. Several …
Electric-Powered Wheelchairs As An Assistive Technology, Aidan O'Dwyer, Malabika Basu, Eugene Coyle
Electric-Powered Wheelchairs As An Assistive Technology, Aidan O'Dwyer, Malabika Basu, Eugene Coyle
Conference papers
This paper briefly outlines recent work done, particularly in control systems, for electric powered wheelchairs. These mobility aids, first developed in the 1950’s [1], were improved with the incorporation of microprocessors. The requirement for mobility aids in general is rising; for example, it is reckoned that 1.5% of the U.K. population require such aids. As an assistive technology, electric powered wheelchairs have many benefits. Nevertheless, a reliable and robust such wheelchair has still to evolve.
Hazardous Emissions Monitoring And Control, Aidan O'Dwyer, Jesus Cabello
Hazardous Emissions Monitoring And Control, Aidan O'Dwyer, Jesus Cabello
Conference papers
There is an increasing awareness in society of the need to protect our fragile environment. Meeting environmental requirements is recognised as one of the six 21st century business drivers for automatic control. Chemical companies, for example, use automatic control to minimise waste production because of increasing prohibitions against discharge and/or disposal of toxic substances. New plants are moving towards a “zero-discharge” concept [1]. In a recent report [2], greater emphasis on automatic control is suggested as a technological response of both the speciality chemicals and pharmaceutical sub-sectors to key business drivers up to 2015. This contribution reports on recent developments …
Using Controller Tuning Formulae To Improve Performance, Aidan O'Dwyer
Using Controller Tuning Formulae To Improve Performance, Aidan O'Dwyer
Conference papers
The proportional integral derivative (PID) controller is the most dominant form of automatic controller in industrial use today. With this device, it is necessary to adjust the controller parameters according to the nature of the process. Thus, for effective control of a HVDC system, for example, specific values need to be chosen for the P, I and D parameters, which will be different for the values required to control, for example, an induction motor drive. This tailoring of controller to process is known as controller tuning. Controller tuning is easily and effectively performed using tuning rules (i.e. formulae for controller …
Performance Improvement Using Simple Pid Controller Tuning Formulae, Aidan O'Dwyer
Performance Improvement Using Simple Pid Controller Tuning Formulae, Aidan O'Dwyer
Conference papers
The proportional integral derivative (PID) controller is the most dominant form of automatic controller in industrial use today. With this technique, it is necessary to adjust the controller parameters according to the nature of the process. Thus, for effective control of a HVDC system, for example, specific values need to be chosen for the P, I and D parameters, which will be different for the values required to control, for example, an induction motor drive. This tailoring of controller to process is known as controller tuning. Controller tuning is easily and effectively performed using tuning rules (i.e. formulae for controller …
Reducing Energy Costs By Optimizing Controller Tuning, Aidan O'Dwyer
Reducing Energy Costs By Optimizing Controller Tuning, Aidan O'Dwyer
Conference papers
The proportional integral derivative (PID) controller is the most dominant form of automatic controller in industrial use today. With this technique, it is necessary to adjust the controller parameters according to the nature of the process. This tailoring of controller to process is known as controller tuning. Controller tuning is easily and effectively performed using tuning rules (i.e. formulae for controller tuning, based on process information). Such tuning rules allow the easy set up of controllers to achieve optimum performance at commissioning. Importantly, they allow ease of re-commissioning if the characteristics of the process change. The paper outlines the results …
An Electro-Oculogram Based System For Communication And Control Using Target Position Variation, Ronan Fitzmaurice, Ted Burke, Annraoi De Paor
An Electro-Oculogram Based System For Communication And Control Using Target Position Variation, Ronan Fitzmaurice, Ted Burke, Annraoi De Paor
Conference Papers
In this paper we describe a novel mode of human computer interaction based on gaze tracking using the electro-oculogram (EOG). Despite the relative simplicity of recording this signal, it is often discounted as a reliable method of gaze tracking because of problems arising from changing sensitivity and DC drift. We describe an original technique, Target Position Variation (TPV), which addresses this issue by presenting moving icons which, when followed with the eye, create a corresponding pattern in the EOG signal which can be used to infer the correct gaze position and to compensate for variations in sensitivity.
Modelling And Control Of A Suspension System For Vehicle Applications, Padraig Dowds, Aidan O'Dwyer
Modelling And Control Of A Suspension System For Vehicle Applications, Padraig Dowds, Aidan O'Dwyer
Conference papers
This paper discusses the modelling of passive and active suspension systems in a car, and the subsequent design of appropriate feedback controllers for the active suspension system. The models will be investigated using a quarter car model and a full car model approach.
Control Loop Performance Assessment: A Classification Of Methods, Niall O'Connor, Aidan O'Dwyer
Control Loop Performance Assessment: A Classification Of Methods, Niall O'Connor, Aidan O'Dwyer
Conference papers
This paper presents an overview of a number of controller performance assessment techniques. The techniques discussed are divided into five categories, namely, time domain assessment, frequency domain assessment, minimum variance control (MVC) as a benchmark, statistical analysis, and other more ‘problem specific’ assessment techniques. Recent work, by various authors, in each of the five categories is outlined.
Closed Loop Identification Of A First Order Plus Dead Time Process Model Under Pi Control, Tony Kealy, Aidan O'Dwyer
Closed Loop Identification Of A First Order Plus Dead Time Process Model Under Pi Control, Tony Kealy, Aidan O'Dwyer
Conference papers
Abstract -- This paper discusses the estimation of the parameters of a first order plus dead-time process model using the closed-loop step response data of the process under proportional plus integral (PI) control. The proportional gain and the integral time, in the PI controller, are chosen such that the closed-loop step response exhibits an under-damped response. From this response data, five characteristic points are used to determine a second order plus dead-time model and subsequently, the frequency response of the closed-loop system. Knowing the dynamics of the closed-loop system and the dynamics of the controller, the open-loop dynamics of the …
Multiple Model Networks In Non-Linear System Modelling For Control – A Review, Ruiyao Gao, Aidan O'Dwyer
Multiple Model Networks In Non-Linear System Modelling For Control – A Review, Ruiyao Gao, Aidan O'Dwyer
Conference papers
Non-linear processes, by their nature, are non-uniform and invariably require custom designed control schemes to deal with individual characteristics. No general theory deals comprehensively with the wide range of non-linear systems encountered. In an attempt to accurately model non-linear dynamical systems, a wide variety of techniques have been developed such as non-linear auto-regressive moving average with exogeneous inputs (NARMAX) models (Chen and Billings, 1989), Weiner models (Schetzen, 1981), Hammerstein models (Billings and Fakhouri, 1982) and Multiple Layer Perceptron (MLP) neural networks (Narendra and Kannan, 1990). While the accuracy of such models offers a potentially significant improvement over linear models, the …
Using Statistics In Industry - Quality Improvement Through Total Process Control, Edward Sweeney, Gordon Betteley, Neville Mettrick, David Wilson
Using Statistics In Industry - Quality Improvement Through Total Process Control, Edward Sweeney, Gordon Betteley, Neville Mettrick, David Wilson
Books/Book chapters
No abstract provided.
Standardised Control Techniques For Induction Generators In Both Grid-Connected And Isolated Applications, John Brazil, Aidan O'Dwyer, M. Murphy
Standardised Control Techniques For Induction Generators In Both Grid-Connected And Isolated Applications, John Brazil, Aidan O'Dwyer, M. Murphy
Conference papers
Induction generators are particularly suitable for small hydro applications and are widely used at present. However, with conventional grid-connected techniques, it is not always possible to use them in regions with weak grids because of excessive connection transients. Consequently, their many advantages cannot be fully exploited in these regions. Standardised control systems have been developed by ECS for isolated applications of induction generators and these will now be further developed to permit reduced-transient grid connections.