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Impact Of Wind Generator Control Strategies On Flicker Emission In Distribution Networks, Lasantha Meegahapola, Sarath Perera
Impact Of Wind Generator Control Strategies On Flicker Emission In Distribution Networks, Lasantha Meegahapola, Sarath Perera
Faculty of Engineering and Information Sciences - Papers: Part A
Renewable power generators are increasingly being integrated to electricity networks to achieve future renewable energy targets in power generation. In particular, wind power generation has already reported substantial penetration levels in electricity networks. Traditionally, flicker phenomenon is considered to be one of the power quality issues in power distribution networks due to fluctuating consumer loads connected to the network. Large-scale integration of wind power generators may create significant voltage fluctuations in distribution feeders due to stochastic and intermittent nature of the wind resources. This study aims to investigate and characterize the flicker emission under different control strategies for DFIG based …
Indian Millennials: Are Microchip Implants A More Secure Technology For Identification And Access Control?, Christine Perakslis, Katina Michael
Indian Millennials: Are Microchip Implants A More Secure Technology For Identification And Access Control?, Christine Perakslis, Katina Michael
Faculty of Engineering and Information Sciences - Papers: Part A
This mixed methods study with a sequential explanatory strategy explored qualitatively the statistically significant quantitative findings relative to Indian respondents' perceptions about RFID (radio frequency identification) transponders implanted into the human body. In the first analysis phase of the study, there was a significant chi-square analysis reported (χ2 = 56.64, df = 3, p =.000) relative to the perception of small business owners (N = 453) that implanted chips are a more secure form of identification and/or access control in organizations and the respondents' country of residence. Countries under study included Australia, India, the UK and US. The country contributing …
Experimental Investigation Of A Hydraulically Interconnected Suspension In Vehicle Dynamics And Stability Control, Lifu Wang, Nong Zhang, Haiping Du
Experimental Investigation Of A Hydraulically Interconnected Suspension In Vehicle Dynamics And Stability Control, Lifu Wang, Nong Zhang, Haiping Du
Faculty of Engineering and Information Sciences - Papers: Part A
Mainly motivated by developing cost-effective vehicle anti-roll systems, hydraulically interconnected suspension has been studied in the past decade to replace anti-roll bars. It has been proved theoretically and practically that hydraulic suspensions have superior anti-roll ability over anti-roll bars, and therefore they have achieved commercial success in racing cars and luxury sports utility vehicles (SUVs). However, since vehicle is a highly coupled complex system, it is necessary to investigate/evaluate the hydraulic-suspension-fitted-vehicle's dynamic performance in other aspects, apart from anti-roll ability, such as ride comfort, lateral stability, etc. This paper presents an experimental investigation of a SUV fitted with a hydraulically …
Robust Sampled-Data Control Of Structures Subject To Parameter Uncertainties And Actuator Saturation, Haiping Du, Nong Zhang, Bijan Samali, Fazel Naghdy
Robust Sampled-Data Control Of Structures Subject To Parameter Uncertainties And Actuator Saturation, Haiping Du, Nong Zhang, Bijan Samali, Fazel Naghdy
Faculty of Engineering and Information Sciences - Papers: Part A
"This paper presents a robust sampled-data controller design approach for vibration attenuation of civil structures considering parameter uncertainties and actuator saturation. The parameter uncertainties belong to polytopic form and are assumed to be the variations of the structural stiffness and damping. Regarding the uncertain sampling problem encountered in real world applications, the sampling period designed for the controller is allowed to be variable within a given bound. In order to obtain reduced peak response quantities, the energy-to-peak performance used to describe the peak values of the control output under all possible energy-bounded disturbances is optimised. The robust sampled-data state feedback …
Robust And Intelligent Control Methods To Improve The Performance Of A Unified Power Flow Controller, C Benachaiba, Ahmed M. Haidar, M L. Doumbia
Robust And Intelligent Control Methods To Improve The Performance Of A Unified Power Flow Controller, C Benachaiba, Ahmed M. Haidar, M L. Doumbia
Faculty of Engineering and Information Sciences - Papers: Part A
The important factor disturbing the modern power systems today is load flow control. The Unified Power Flow Controller (UPFC) is an effective way for controlling the power flow and can provide damping capability during transient conditions. The UPFC is controlled conventionally using PI controller. This paper presents two robust controllers to improve the performance of the UPFC. The first is a RST controller based on the principle of pole placement and the second is an intelligent controller based on the principle of fuzzy logic optimized by Genetic Algorithm (GA).
Collaborative Management Of Web Ontology Data With Flexible Access Control, Jie Lu, Chao Wang, Guangquan Zhang, Jun Ma
Collaborative Management Of Web Ontology Data With Flexible Access Control, Jie Lu, Chao Wang, Guangquan Zhang, Jun Ma
Faculty of Engineering and Information Sciences - Papers: Part A
The creation and management of ontology data on web sites (e.g. instance data that is used to annotate web pages) is important technical support for the growth of the semantic web. This study identifies some key issues for web ontology data management and describes an ontology data management system, called robinet, to perform the management. This paper presents the structure of the system and introduces a Web ontology data management model that enables a flexible access control mechanism. This model adds rules into the robinet system to utilize the semantics of ontology for controlling the access to ontology data. The …
Humanoid Human-Like Reaching Control Based On Movement Primitives, Minh Tuan Tran, Philippe Souères, Michel Taix, Manish Sreenivasa, Christophe Halgand
Humanoid Human-Like Reaching Control Based On Movement Primitives, Minh Tuan Tran, Philippe Souères, Michel Taix, Manish Sreenivasa, Christophe Halgand
Faculty of Engineering and Information Sciences - Papers: Part B
This paper deals with the problem of generating realistic human-like reaching movements from a small set of movement primitives. Two kinds of movement databases are used as reference. The first one is obtained numerically, by applying biological principles of motor control on the dynamic model of the robot arm. The second one is obtained by recording reaching movements of human subjects. From these databases, primitives are extracted and analyzed by using Principal Component Analysis. An original generalization method is then proposed for generating movements that did not belong to the initial database. We show that twenty primitives allow to produce …
Hrp-2 Plays The Yoyo: From Human To Humanoid Yoyo Playing Using Optimal Control, Katja Mombaur, Manish Sreenivasa
Hrp-2 Plays The Yoyo: From Human To Humanoid Yoyo Playing Using Optimal Control, Katja Mombaur, Manish Sreenivasa
Faculty of Engineering and Information Sciences - Papers: Part B
Yoyo playing may seem easy for a human, but it is a challenging problem for a humanoid robot. This paper presents an approach to generate yoyo motions for the humanoid robot, HRP-2, based on motion recorded from human yoyo playing, dynamical models and numerical optimal control techniques. We recorded vertical yoyo playing of 4 subjects measuring yoyo height and rotation angle as well as the corresponding hand motions. A detailed multi-phase yoyo model with impact collisions and control patterns of human yoyo playing were identified from these measurements. Based on this knowledge, reliable yoyo motions within the feasibility ranges of …
Harmonic Elimination Control Of A Five-Level Dc-Ac Cascaded H-Bridge Hybrid Inverter, Georgios S. Konstantinou, Sridhar R. Pulikanti, Vassilios G. Agelidis
Harmonic Elimination Control Of A Five-Level Dc-Ac Cascaded H-Bridge Hybrid Inverter, Georgios S. Konstantinou, Sridhar R. Pulikanti, Vassilios G. Agelidis
Faculty of Engineering and Information Sciences - Papers: Part A
A five-level hybrid cascaded inverter operating under selective harmonic elimination (SHE) pulse-width modulation (PWM) control is discussed in this paper. The topology is a cascaded connection of a conventional three-phase, two-level inverter and an H-bridge module for each phase with a single DC-source. The topology boosts the output voltage within limits and with no additional DC-DC converters. However, such boosting feature depends on the control of the floating capacitor voltage and the load power factor. The regulation of the floating capacitor for the given modulation strategy is also analyzed. Experimental results taken from a single-phase laboratory prototype are presented to …
Inverse Optimal Control As A Tool To Understand Human Yoyo Playing, Katja Mombaur, Manish Sreenivasa
Inverse Optimal Control As A Tool To Understand Human Yoyo Playing, Katja Mombaur, Manish Sreenivasa
Faculty of Engineering and Information Sciences - Papers: Part B
This paper presents an inverse optimal control approach to identify objective functions of human motion from motion capture measurements. We apply it to analyze human yoyo playing. Yoyo playing may seem easy to us to learn but it is a challenging problem from a mechanical point of view involving a hybrid dynamics model. We recorded vertical yoyo playing of humans measuring yoyo height and rotation angle as well as the corresponding hand motions. Results of inverse optimal control are presented showing a mixed criterion of cycle time and terms depending on yoyo and hand acceleration and velocity.
A Control Strategy For Output Maximisation Of A Pmsg-Based Variable-Speed Wind Turbine, M E. Haque, K M. Muttaqi, M Negnevitsky
A Control Strategy For Output Maximisation Of A Pmsg-Based Variable-Speed Wind Turbine, M E. Haque, K M. Muttaqi, M Negnevitsky
Faculty of Engineering and Information Sciences - Papers: Part A
This paper presents a control strategy for output maximisation of a direct drive permanent magnet synchronous generator (PMSG)-based small-scale variable-speed wind turbine. The control topology uses a single switch three-phase switch-mode rectifi er and the generator torque, and power is controlled by controlling the switch duty cycle of the switch. To extract maximum power from the wind, the torque reference of the PMSG is calculated from generator speed and wind turbine characteristics. From this torque reference, a current reference is calculated using measured DC link voltage and generator speed. The current error is then used to control the duty cycle …
A Novel Dynamic Absorber Using Enhanced Magnetorheological Elastomers For Powertrain Vibration Control, Nong Zhang, Nga Hoang, Haiping Du
A Novel Dynamic Absorber Using Enhanced Magnetorheological Elastomers For Powertrain Vibration Control, Nong Zhang, Nga Hoang, Haiping Du
Faculty of Engineering and Information Sciences - Papers: Part A
This paper presents a novel Adaptive Tuned Vibration Absorber (ATVA) using the enhanced magnetorheological elastomers (MREs) for powertrain vibration reduction. The MRE material used in this application includes micro-sized iron particles enhanced by adding nano-sized magnetic powders. With the enhancement, MRE's elastic modulus significantly increases due to the MR effect. In the new ATVA, the MRE plays a role as a torsional spring whose stiffness coefficient can be varied with an external magnetic field. Additionally, this ATVA could operate in shear-squeeze mode rather than shear mode. Thus, the frequency range is much wider than that of general MREs. Such property …
Editorial: Special Issue Contributed From Chemeca 2006-Australasian Process Modelling And Control Selected Papers, Mark Nelson, Brent Young
Editorial: Special Issue Contributed From Chemeca 2006-Australasian Process Modelling And Control Selected Papers, Mark Nelson, Brent Young
Faculty of Engineering and Information Sciences - Papers: Part A
The papers in this issue of Chemical Product and Process Modelling are substantially those that arose from special sessions on ``process simulation and control" (organised by Brent R. Young) and ``mathematical modeling" (organised by Mark I. Nelson) at the 34th Australasian Chemical Engineering Conference (held between 17-20th September 2006, in Auckland, New Zealand). The papers in this special issue are available at: http://www.bepress.com/cppm/vol2/iss2. The papers featured in this issue have been revised and extended from CHEMECA and re-reviewed before publication here.All the papers in this issue use mathematics. However, this special issue only features a small number of the presentations …
Five-Level Active Npc Converter Topology: She-Pwm Control And Operation Principles, Sridhar Reddy Pulikanti, Vassilios G. Agelidis
Five-Level Active Npc Converter Topology: She-Pwm Control And Operation Principles, Sridhar Reddy Pulikanti, Vassilios G. Agelidis
Faculty of Engineering and Information Sciences - Papers: Part A
The neutral-point-clamped (NPC) inverter topology has been the centre of research and development effort for numerous applications, including medium- and high-voltage electric motor drives, static compensators (STATCOMs) and other utility type of power electronic systems for almost three decades now. Pulse-width modulation (PWM) control methods have been developed for such topology for respective three-level and multilevel versions. The issue of voltage balancing between the DC bus capacitors is a drawback that requires attention and the problem becomes more serious as the number of levels increases. Selective harmonic elimination PWM can be applied to control the topology as a method to …
Distributed Generation Control Using Protection Principles, An D. T Le, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich
Distributed Generation Control Using Protection Principles, An D. T Le, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich
Faculty of Engineering and Information Sciences - Papers: Part A
No abstract provided.
Control Stabilisation Of An Islanded System With Dfig Wind Turbine, M Aktarujjaman, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich
Control Stabilisation Of An Islanded System With Dfig Wind Turbine, M Aktarujjaman, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich
Faculty of Engineering and Information Sciences - Papers: Part A
Distributed Generation (DG) is often used to export power to the utility system. Loss of main supply can cause a severe loading mismatch between DG generation and load consumption. Consequently, the voltage and frequency of the islanded system will cross the allowable limit. Due to this fact, it is essential to control the voltage and frequency in the islanding mode of operation. In this paper, control stabilisation of an islanded system with a doubly-fed induction generator (DFIG) wind turbine has been addressed. Wind DG produces variable output and is not capable to produce enough reactive power. Hence, it is imperative …
Control Strategy Of Distributed Generation For Voltage Support In Distribution Systems, An D. T Le, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich
Control Strategy Of Distributed Generation For Voltage Support In Distribution Systems, An D. T Le, Kashem M. Muttaqi, Michael Negnevitsky, Gerard Ledwich
Faculty of Engineering and Information Sciences - Papers: Part A
Voltage problem is always a critical issue in operating a distribution system. The uncertainties of load distribution and variation have introduced a great complexity to the task of maintaining system voltage within the permitted range. In this paper, small-scale generator, known as distributed generation (DG), is employed in the system and acting as a voltage regulator. The output of DG is controlled in such a way that acceptable level of electrical supply quality is achieved with a reasonable operating cost. The DG controller is tested with a non-uniformly varying load on the time domain basis. Simulations have been conducted with …
Hydro-Turbine Governor Control: Theory, Techniques And Limitations, J Culberg, Michael Negnevitsky, Kashem M. Muttaqi
Hydro-Turbine Governor Control: Theory, Techniques And Limitations, J Culberg, Michael Negnevitsky, Kashem M. Muttaqi
Faculty of Engineering and Information Sciences - Papers: Part A
With the entry of Tasmania into the national electricity market, equipment upgrades are required in many parts of the existing power system. This presents an opportunity to embrace new technology, in order to enhance the current efficiency and productivity of the system. One area is that of hydro-turbine speed governors, an integral part of maintaining the frequency of the output. This paper analyses the current standard control algorithm for turbine governors, the PID controller. It illustrates the processes involved, tuning and their limitations. Finally, alternative control systems are discussed.
Dynamic Channel Allocation For Mobile Cellular Systems Using A Control Theoretical Approach, Yaya Wei, Chuang Lin, Raad Raad, Fengyuan Ren
Dynamic Channel Allocation For Mobile Cellular Systems Using A Control Theoretical Approach, Yaya Wei, Chuang Lin, Raad Raad, Fengyuan Ren
Faculty of Engineering and Information Sciences - Papers: Part A
The guard channel scheme in wireless mobile networks has attracted and is still drawing research interest owing to easy implementation and flexible control. Dynamic guard channel schemes have already been proposed in the literature to adapt to varying traffic load. This paper presents a novel control-theoretic approach to dynamically reserve guard channels called PI-Guard Channel (PI-GC) controller that maintains the handoff blocking probability (HBP) to a predefined value; while it still improves the channel resource utilization.
Mr Damper And Its Application For Semi-Active Control Of Vehicle Suspension System, G Z. Yao, F F. Yap, G Chen, Weihua Li, S H. Yeo
Mr Damper And Its Application For Semi-Active Control Of Vehicle Suspension System, G Z. Yao, F F. Yap, G Chen, Weihua Li, S H. Yeo
Faculty of Engineering and Information Sciences - Papers: Part A
In this paper, a semi-active control of vehicle suspension system with magnetorheological (MR) damper is presented. At first a MR damper working in flow mode is designed. Performance testing is done for this damper with INSTRON machine. Then a mathematical model, Bouc–Wen model, is adopted to characterize the performance of the MR damper. With optimization method in MATLAB® and experimental results of MR damper, the coefficients of the model are determined. Finally, a scaled quarter car model is set up including the model of the MR damper and a semi-active control strategy is adopted to control the vibration of …
Wiener Model Identification And Predictive Control For Dual Composition Control Of A Distillation Column, H H J Bloemen, C T. Chou, T J J Van Den Boom, V Verdult, M Verhaegen, T C. Backx
Wiener Model Identification And Predictive Control For Dual Composition Control Of A Distillation Column, H H J Bloemen, C T. Chou, T J J Van Den Boom, V Verdult, M Verhaegen, T C. Backx
Faculty of Engineering and Information Sciences - Papers: Part A
The benefits of using the Wiener model based identification and control methodology presented in this paper, compared to linear techniques, are demonstrated for dual composition control of a moderate-high purity distillation column simulation model. An identification experiment design is presented which enables one to identify both the low and high gain directions of the distillation column, properties which are important for control and hard to identify in a conventional identification experiment setup as is demonstrated in the paper. Data from the proposed experiment design is used for indirect closed-loop identification of both a linear and a Wiener model, which shows …
Developments In Blast Furnace Process Control At Port Kembla Based On Process Fundamentals, Robert Nightingale, Rian Dippenaar, Wei-Kao Lu
Developments In Blast Furnace Process Control At Port Kembla Based On Process Fundamentals, Robert Nightingale, Rian Dippenaar, Wei-Kao Lu
Faculty of Engineering and Information Sciences - Papers: Part A
This article is based on a presentation made in the "Geoffrey Belton Memorial Symposium," held in January 2000, in Sydney, Australia, under the joint sponsorship of ISS and TMS.
The Interpretation Of Laser Sensing Measurements For Blast Furnace Operations And Control, Peter C. Wall, R J Turner, Mark Hughes, Peter Huk, Ross J. Haywood, M J Mccarthy, Paul Zulli
The Interpretation Of Laser Sensing Measurements For Blast Furnace Operations And Control, Peter C. Wall, R J Turner, Mark Hughes, Peter Huk, Ross J. Haywood, M J Mccarthy, Paul Zulli
Faculty of Engineering and Information Sciences - Papers: Part A
Several laser-based sensors for use on blast furnaces have been developed and implemented, including a raceway sensor, burden level sensor (single point) and burden surface profiler. These sensors are based on the time-of-flight technique and give high levels of accuracy in all applications. The data obtained from the sensors during normal furnace operations are examined in light of the process models utilised by operators and for the interpretation of pulverised coal injection performance. Raceway sensory data obtained during a furnace blow-in are also discussed.