Engineering Commons^™

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 …

Protection Of Dvr Against Short Circuit Faults At The Load Side, Iurie Axente, Malabika Basu, Michael Conlon, Kevin Gaughan

Conference papers

An additional control scheme has been proposed in this paper for a dynamic voltage restorer (DVR), to protect it against load short circuit conditions. When overcurrents occur in the distribution system, under the proposed scheme the DVR reverses its injected voltage polarity so as to minimise the current flow. The detection method is based on impedance measurement feedback. The advantage of the scheme is that no additional over current device or protection is required for the DVR and it is easy to implement. The proposed control scheme has been validated through simulation.

A Case Study In Modeling And Process Control: The Control Of A Pilot Scale Heating And Ventilation System, Robin Mooney, Aidan O'Dwyer

Conference papers

This paper details the control of a pilot scale laboratory heating and ventilation system. The system is represented in 2x2 multi-input, multi-output (MIMO) form. A process reaction curve identification technique was used to model (in first order lag plus delay - FOLPD - form) the flow process and temperature process portions of the system, over a range of operating conditions. Tests revealed that both processes were continuously non-linear. A gain scheduler with static decoupling was designed, using look-up tables, to continuously interpolate for the most suitable proportional-integral (PI) or proportional-integral-derivative (PID) controller settings and decoupler gains. The contribution of this …

Pi And Pid Controller Tuning Rules: An Overview And Personal Perspective, Aidan O'Dwyer

Conference papers

The ability of PI and PID controllers to compensate many practical processes has led to their wide acceptance in industrial applications. The requirement to choose two or three controller parameters is most easily done using tuning rules. Starting with a general discussion of industrial practice, the paper provides a survey of additional tuning rules for continuous-time PI and PID control of time-delayed single-input, single-output (SISO) processes, to those explored in a recent book by the author.

Experiences Of Learning And Teaching On A Taught Masters Course In Engineering: From A Didactic Approach To A More Student Centered Learning Approach, Aidan O'Dwyer

Conference papers

This paper reports on, reflects on, and evaluates the author’s experiences of teaching the Advanced Control module on the Masters degree in Advanced Engineering at Dublin Institute of Technology (DIT) over the past four academic years. The teaching approach has evolved from a traditional didactic lecture and laboratory course, with associated assessments, in the first academic year, to the implementation of a more learner-centred approach over the past two academic years. This new approach has been made possible by the appropriate use of real case studies, information technology tools, and web-based virtual laboratories. Assessment methodology has also evolved. In the …

Enhancing Waste Management Through Automatic Control, Aidan O'Dwyer

Conference papers

Meeting environmental requirements is recognised as one of the six 21st century business drivers for automatic control. The proportional integral (PI) and proportional integral derivative (PID) controllers are the most dominant form of automatic controllers in industrial use today. With these techniques, it is necessary to adjust the controller parameters according to the nature of the process. Thus, for effective control of a heating, cooling and air-conditioning (HVAC) application, 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, a distillation column. This …

Controlled Braking Scheme For A Wheeled Walking Aid, Eugene Coyle, Aidan O'Dwyer, Eileen Young, Kevin Sullivan, A. Toner

Conference papers

A wheeled walking aid with an embedded controlled braking system is described. The frame of the prototype is based on combining features of standard available wheeled walking aids. A braking scheme has been designed using hydraulic disc brakes to facilitate accurate and sensitive controlled stopping of the walker by the user, and if called upon, by automatic action. Braking force is modulated via a linear actuating stepping motor. A microcontroller is used for control of both stepper movement and for supervisory control. An encoder is used to supervise walker movement in terms of time, distance and speed.

An Approach To Teaching Pid Controller Tuning, Aidan O'Dwyer

Conference papers

This paper discusses an approach to the teaching of PID controller tuning methods to students in control engineering at Dublin Institute of Technology. The method involves analytically calculating the gain margin, phase margin and maximum sensitivity for PI and PID controlled systems whose process is modelled in first order lag plus time delay (FOLPD) form. Students can examine the performance of many tuning rules from graphical results, allowing insight to be developed as to the most rational choice of the tuning rule for the application. Some preliminary work done to develop an expert system to allow a greater automation of …

Quarter-Wave Metal Plate Solar Antenna, S. Shynu, Max Ammann, Brian Norton

Articles

A novel design of a quarter-wave shorted trapezoidal metal plate solar antenna using high efficiency polycrystalline silicon solar cells is presented. Using the DC conductive parts of the cell as RF antenna elements as well as choosing the radiating element to be a small base trapezoid, better coupling between the the feed and shorting plates is ensured and 40.3% size reduction compared to a conventional shorted quarter-wave patch is obtained. The trapezoidal radiating element covers merely 2.7% of the total available illumination area of the solar cell, leaving its efficiency essentially unaffected. The proposed design strategy has been verified by …

Design, Modelling And Simulation Of An Innovative Trefoil Rotary Kiln Pilot Plant, Mick Mckeever

Doctoral

This work investigates the contribution modelling makes when integrated into the pilot plant development stage of a new synthetic aggregate manufacturing process. The pilot plant is based around a novel rotary kiln, unique in design from standard kilns. The kiln has a trefoil cross sectional profile and a low thermal mass. A dynamic simulation model of the kiln was built to simulate the thermal behaviour of the pilot plant and the movement of the pelletised aggregate as it travels through the kiln drum.

As part of the preliminary work, a measurement and data acquisition subsystem was commissioned to allow data …

Planar Antennas, Zhi Ning Cheng, Max Ammann, Xianming Qing, Xuan Hui Wu, T. S.P. See, A. Cai

Articles

This article reviews the state of the art in broadband antennas for emerging UWB applications and addresses the important issues of the broadband antenna design for UWB applications. First, a variety of planar monopoles with finite ground planes are reviewed. Next, the roll antennas with enhanced radiation performance are outlined. After that, the planar antennas printed on PCBs are described. A directional antipodal Vivaldi antenna is also presented for UWB applications. Last, a UWB antenna for wearable applications is exemplified

Compact Concentric Annular-Ring Patch Antenna For Triple Frequency Operation, Xiulong Bao, Max Ammann

Articles

A novel single-layer, single-feed concentric annular-ring microstrip patch antenna providing triple-frequency operation is proposed and experimentally studied. This is achieved by embedding a small circular patch into a dual stub-loaded concentric annular-ring structure and by employing a cross-slot in the ground plane. The proposed technique can provide triple-band operation and reduce the antenna size by over 50% compared to the conventional annular-ring patch antenna for a given frequency. Experimental results show the proposed antenna to have impedance bandwidths of 6.38, 6.30 and 35% for the three bands, at 1.17, 1.428 and 1.9 GHz, respectively. The proposed structure is capable of …

Design Of One-Dimensional Composite Photonic Crystals With An Extended Photonic Band Gap, Vladimir Tolmachev, Kevin Berwick

Articles

A technique for photonic band gap (PBG) extension based on mixing photonic crystals with different lattice constants or filling factors is suggested. For the design of photonic crystals with maximal PBG extension the gap map imposition method is utilized. Gap maps for composite photonic crystals based on Si-air structures are calculated and used to predict optimal structures for fabrication.

Ber Variation In An Uwb Ofdm Mimo Communications System Based On Measurements Made In A Picocell Wireless Environment, Pat Chambers, Conor Downing, Hussein Baher

Conference papers

A picocell UWB MIMO communications system model is considered which has five orthogonal sub-channels, each with its own OFDM signal. The effect of removing the various channel impulse response components which arise due to the multi-path propogation, a phenomenon characteristic of wide band transmission, is considered. This is a measurement based analysis where the measurements, themselves, were made, in a specially constructed enclosure which had reflective surfaces, using specially designed UWB antennas.

A Compact Wide-Band Shorted Folded Antenna, Giuseppe Ruvio, Max Ammann

Conference papers

No abstract provided.

Design Of A Wide-Band Printed Antenna Using A Genetic Algorithm On An Array Of Overlapping Sub-Patches, Matthias John, Max Ammann

Conference papers

No abstract provided.

Investigation On Annular-Ring Patch Antenna With Ebg Structure, Xiulong Bao, Giuseppe Ruvio, Max Ammann

Conference papers

An annular-ring loaded circular patch antenna with slot-ring array of EBG cells on the ground plane is presented. A comparison is made between the annular ring loaded patch on a conventional PEC groundplane and the same patch on a groundplane with a 2x2, a 4x4 and a 6x6 slot-ring EBG array. It was found that the annular-ring patch antenna with a 4 x 4 slot-ring array in the ground plane is superior in the overall performance (gain, impedance and axial-ratio bandwidth). The array of EBG was found to improve gain by 3.5dB and increase the bandwidth of input impedance by …

High Performance Circularly Polarized Antenna Based On Fractal Ebg Structure, Xiulong Bao, Max Ammann, Giuseppe Ruvio, Matthias John

Conference papers

Circularly polarized patch antennas have been widely applied in wireless communication system, global positioning system, etc., because of their low-profile, lightweight, ease of fabrication and low lost [1,2]. To achieve high performance for circularly polarized patch antennas, some new structures were reported in the literature, such as antennas array, stack layer antennas, using periodic structures [3-7], etc. In this paper, a high performance circularly polarized low frequency patch antenna based on the compact fractal high-impedance surface EBG structure has been fabricated and experimented. The measured results show that the proposed circularly polarized patch antenna has good performance in impedance bandwidth, …

Synthesising Life-Sciences And Control Engineering: An Outline Survey And A Practical Example, Aidan O'Dwyer

Conference papers

There is an increasing interest in life science related areas in the electrical and control engineering community [1]. One manifestation of this interest is the development of interdisciplinary programmes, such as the B.Sc. in Medical Physics and Bioengineering, offered by the Dublin Institute of Technology from September 2005. A significant amount of research work in control engineering has focused on aspects of human physiological system, for example blood glucose regulation [2], cardiovascular modelling and control [3], and limb control [4]. There is an increasing emphasis on interdisciplinary research; in recognition of this, the Institute of Electrical Engineers (IEE) has starting …

Rating Requirements Of A Unified Power Quality Conditioner (Upqc) For Voltage Ride Through Capability Enhancement, N. G. Jayanti, Malabika Basu, Michael Conlon, Kevin Gaughan

Conference papers

The problem of voltage ride through capability of fixed speed wind generation as a result of voltage sags is examined by means of a simulation study. The role of a Unified Power Quality Conditioner (UPQC), which provides both shunt and series compensation, in enhancing the ride through capability is investigated under both full and partial voltage restoration. Results of a study to identify the minimum rating requirements to ensure stability are presented.

A Wavelet Controller For Shunt Active Power Filter, Malabika Basu, Biswajit Basu

Conference papers

A wavelet-based controller for shunt active power filter (APF) has been proposed in this paper. The constructed controller based on multi resolution analysis has the advantage of better frequency bandwidth selection. The tuning parameters of the controllers are the gains to be applied to the time-frequency signals at different resolutions. This has the advantage of aiding the process of a proper choice of coefficients of tuning parameters. The developed simulation model of the APF with wavelet-based control shows satisfactory steady state and dynamic performance. A comparison with standard PI controller shows that the dynamic response of the proposed wavelet controller …

Optimising The Rating Of The Upqc For Applying To The Fault Ride Through Enhancement Of Wind Generation, N. G. Jayanti, Malabika Basu, Michael Conlon, Kevin Gaughan

Conference papers

The unified power quality conditioner (UPQC) is a combination of a shunt and a series compensator cascaded via a DC link capacitor which works on the combined principle of active filtering and dynamic voltage restoration. Therefore, the UPQC can be a potential solution to the grid integration problems associated with fixed speed wind generators including reactive power compensation and fault ride through capability. The hardware design of the UPQC can be made more cost effective by proper selection of the rating of the individual compensators of the UPQC. It is shown in the paper that the application of a fixed …

Ecue: A Spam Filter That Uses Machine Learning To Track Concept Drift, Sarah Jane Delany, Padraig Cunningham, Barry Smyth

Conference papers

While text classification has been identified for some time as a promising application area for Artificial Intelligence, so far few deployed applications have been described. In this paper we present a spam filtering system that uses example-based machine learning techniques to train a classifier from examples of spam and legitimate email. This approach has the advantage that it can personalise to the specifics of the user’s filtering preferences. This classifier can also automatically adjust over time to account for the changing nature of spam (and indeed changes in the profile of legitimate email). A significant software engineering challenge in developing …

The R-Cube: Reviewing, Reinforcing And Rewarding After Successful Module Completion, Ciaran O'Leary

Conference papers

Revisiting material previously presented and successfully assessed can lead to much frustration among teaching staff and students. Despite this, it is often a requirement due to the time lag between the point at which a student begins a module and the time when they successfully passed a prerequisite module. Also, students who successfully pass a module fit into a number of categories, from those who were successful in all components of the assessment to those who displayed the minimum level of competence required for satisfaction of the learning outcomes. We introduce a novel instructional model which we predict will be …