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- Faculty of Engineering and Information Sciences - Papers: Part A (51)
- Dr Lasantha G Meegahapola (12)
- Faculty of Engineering and Information Sciences - Papers: Part B (10)
- Dr Fenghui Ren (2)
- Dr Philip Ciufo (2)
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- Associate Professor Katina Michael (1)
- Dams: Water and Power in the New West (Summer Conference, June 2-4) (1)
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- Journal of Digital Forensics, Security and Law (1)
- M. G. Michael (1)
- Open Access Theses & Dissertations (1)
- Professor Katina Michael (1)
- Robert Barr (1)
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Articles 31 - 60 of 86
Full-Text Articles in Engineering
Energy-Efficiency Analysis Of Per-Subcarrier Antenna Selection With Peak-Power Reduction In Mimo-Ofdm Wireless Systems, Ngoc Phuc Le, Le Chung Tran, Farzad Safaei
Energy-Efficiency Analysis Of Per-Subcarrier Antenna Selection With Peak-Power Reduction In Mimo-Ofdm Wireless Systems, Ngoc Phuc Le, Le Chung Tran, Farzad Safaei
Faculty of Engineering and Information Sciences - Papers: Part A
The use of per-subcarrier antenna subset selection in OFDM wireless systems offers higher system capacity and/or improved link reliability.However, the implementation of the conventional per-subcarrier selection schememay result in significant fluctuations of the average power and peak power across antennas, which affects the potential benefits of the system. In this paper, power efficiency of high-power amplifiers and energy efficiency in per-subcarrier antenna selection MIMO-OFDM systems are investigated. To deliver the maximum overall power efficiency, we propose a two-step strategy for data-subcarrier allocation.This strategy consists of an equal allocation of data subcarriers based on linear optimization and peak-power reduction via cross-antenna …
Power Allocation Algorithm In Ofdm-Based Cognitive Radio Systems, Van Vinh Nguyen, Yang Shouyi, Le Chung Tran
Power Allocation Algorithm In Ofdm-Based Cognitive Radio Systems, Van Vinh Nguyen, Yang Shouyi, Le Chung Tran
Faculty of Engineering and Information Sciences - Papers: Part A
In orthogonal frequency division multiplexing (OFDM)-based cognitive radio (CR) systems, the optimized algorithms for sub-carrier power allocation face the problems of complex iterative calculation and difficult realization. In this paper, we propose an exponential power distribution function and derive a sub-optimal power allocation algorithm. This algorithm aims to allocate power of in-band subcarriers of cognitive users according to the numerical characteristics of the power distribution function by using a convex optimization numerical method under linear constraints. This algorithm has the advantages of fast calculation speed and easy realization, and reduces the interference to the authorized users, which is caused by …
Transmit Antenna Subset Selection For High-Rate Mimo-Ofdm Systems In The Presence Of Nonlinear Power Amplifiers, Phuc Ngoc Le, Farzad Safaei, Le Chung Tran
Transmit Antenna Subset Selection For High-Rate Mimo-Ofdm Systems In The Presence Of Nonlinear Power Amplifiers, Phuc Ngoc Le, Farzad Safaei, Le Chung Tran
Faculty of Engineering and Information Sciences - Papers: Part A
The deployment of antenna subset selection on a per-subcarrier basis in MIMO-OFDM systems could improve the system performance and/or increase data rates. This paper investigates this technique for the MIMO-OFDM systems suffering nonlinear distortions due to high-power amplifiers. At first, some problems pertaining to the implementation of this antenna selection approach, including power imbalance across transmit antennas and non-causality of per-subcarrier antenna selection criteria, are identified. Next, an optimal selection scheme is devised by means of linear optimization to overcome those disadvantages. This scheme optimally allocates data subcarriers under a constraint that all antennas have the same number of data …
A Review Of Technical Challenges In Planning And Operation Of Remote Area Power Supply Systems, Yingjie Tan, Lasantha Meegahapola, Kashem M. Muttaqi
A Review Of Technical Challenges In Planning And Operation Of Remote Area Power Supply Systems, Yingjie Tan, Lasantha Meegahapola, Kashem M. Muttaqi
Faculty of Engineering and Information Sciences - Papers: Part A
Remote area power supply (RAPS) systems are being used for many years to supply power to rural or remote communities where the utility grid is not accessible. In order to avoid the high operating cost and environmental impact caused by conventional generators, renewable energy resources are currently being utilised in RAPS systems. However, the intermittency of such renewable energy resources greatly impacts on planning and operation of RAPS systems. This paper aims to present a comprehensive review with regard to the RAPS system planning and operation techniques published in the literature. This paper summarises different modelling approaches associated with the …
Dispatch Strategy To Minimise Uncertainty In Wind Power Generation In The Australian National Electricity Market, Amila Wickramasinghe, Lasantha G. Meegahapola, Ashish P. Agalgaonkar, Sarath Perera
Dispatch Strategy To Minimise Uncertainty In Wind Power Generation In The Australian National Electricity Market, Amila Wickramasinghe, Lasantha G. Meegahapola, Ashish P. Agalgaonkar, Sarath Perera
Faculty of Engineering and Information Sciences - Papers: Part A
2014 ACPE. With increased penetration of wind power, scheduling generators to meet the forecast demand of a power system is becoming an increasingly challenging task for the system operators. Uncertainty associated with the generation expected from wind plants adds to the load demand uncertainty, making it necessary to retain additional reserves to maintain the balance between demand and supply of power. In the Australian national electricity market (NEM), sophisticated wind forecasting techniques are employed to reduce the uncertainty in wind generation. Despite being able to project the contribution of wind power to a reasonable accuracy, wind power plants are currently …
Smart Home Electricity Management In The Context Of Local Power Resources And Smart Grid, Weiliang Zhao, Lan Ding, Paul Cooper, Pascal Perez
Smart Home Electricity Management In The Context Of Local Power Resources And Smart Grid, Weiliang Zhao, Lan Ding, Paul Cooper, Pascal Perez
Faculty of Engineering and Information Sciences - Papers: Part A
This work proposes a smart home electricity management approach that can predict and schedule electricity demand and supply by considering: the 'state' of the smart grid, local power generation capacity, and electrical consumption of household appliances. The prediction of weather conditions and the immediate and longer-term plans of the residential home occupants are crucial parameters in the smart home decision-making system that acts on behalf of the occupants. This paper provides a motivation example and associated scenarios, electrical energy supply/demand models, formalization of the cost optimization problem, and scheduling schemes for a smart home electricity management system in the context …
Solar Pv Power Generation Forecasting Using Hybrid Intelligent Algorithms And Uncertainty Quantification Based On Bootstrap Confidence Intervals, Donna Alhakeem
Solar Pv Power Generation Forecasting Using Hybrid Intelligent Algorithms And Uncertainty Quantification Based On Bootstrap Confidence Intervals, Donna Alhakeem
Open Access Theses & Dissertations
This Thesis focuses on short-term photovoltaic forecasting (STPVF) for the power generation of a solar PV system using probabilistic forecasts and deterministic forecasts. Uncertainty estimation, in the form of a probabilistic forecast, is emphasized in this Thesis to quantify the uncertainties of the deterministic forecasts. Two hybrid intelligent models are proposed in two separate chapters to perform the STPVF. In Chapter 4, the framework of the deterministic proposed hybrid intelligent model is presented, which is a combination of wavelet transform (WT) that is a data filtering technique and a soft computing model (SCM) that is generalized regression neural network (GRNN). …
Impact Of Wind Generation Mix On Transient Stability For An Interconnected Power System, Lasantha Meegahapola, Damian Flynn, Jason Kennedy, Tim Littler
Impact Of Wind Generation Mix On Transient Stability For An Interconnected Power System, Lasantha Meegahapola, Damian Flynn, Jason Kennedy, Tim Littler
Dr Lasantha G Meegahapola
The rapid growth of wind generation in many European countries is pushing power systems into uncharted territory. As additional wind generators are installed, the changing generation mix may impact on power system stability. This paper adopts the New England 39 bus system as a test system for transient stability analysis. Thermal generator models are based on a likely future plant mix for existing systems, while varying capacities of fixed-speed induction generators (FSIG) and doubly-fed induction generators (DFIG) are considered. The main emphasis here has been placed on the impact of wind technology mix on inter-area oscillations following transient grid disturbances. …
Characterisation Of Flicker Emission And Propagation In Distribution Networks With Bi-Directional Power Flows, D Perera, L Meegahapola, S Perera, P Ciufo
Characterisation Of Flicker Emission And Propagation In Distribution Networks With Bi-Directional Power Flows, D Perera, L Meegahapola, S Perera, P Ciufo
Dr Lasantha G Meegahapola
With the increasing penetration levels of intermittent and fluctuating energy sources such as wind generating systems in the electricity grid, resulting voltage fluctuations and flicker can be expected to become an important power quality considerations. Due to significant bidirectional power flows resulting from large renewable power generation systems connected to downstream, voltage fluctuations may propagate from downstream to upstream. The work presented in this paper investigates and characterises flicker emission and propagation resulting from fluctuating generating sources connected to a distribution network. Mathematical models are developed for flicker emission under different generator control strategies and flicker propagation to upstream network. …
Comparative Analysis Of Dynamic Line Rating Models And Feasibility To Minimise Energy Losses In Wind Rich Power Networks, Mathew Simms, Lasantha Meegahapola
Comparative Analysis Of Dynamic Line Rating Models And Feasibility To Minimise Energy Losses In Wind Rich Power Networks, Mathew Simms, Lasantha Meegahapola
Dr Lasantha G Meegahapola
Wind power generation has indicated an exponential increase during last two decades and existing transmission network infrastructure is increasingly becoming inadequate to transmit remotely generated wind power to load centres in the network. The dynamic line rating (DLR) is one of the viable solutions to improve the transmission line ampacity during high wind penetration without investing on an additional transmission network. The main objective of this study is to identify the basic differences between two main line rating standards, since transmission network service providers (TNSPs) heavily depend on these two standards when developing their line rating models. Therefore, a parameter …
Optimal Power Flow With Variable Wind Conditions, S Durairaj, L Meegahapola, D Flynn, B Fox
Optimal Power Flow With Variable Wind Conditions, S Durairaj, L Meegahapola, D Flynn, B Fox
Dr Lasantha G Meegahapola
This paper presents simulation studies of an electric arc furnace (EAF) model in the MATLAB/SIMULINK environment. EAF was modeled as a current source controlled by a non-linear resistance. Voltage flicker, a phenomenon of annoying light intensity fluctuation, caused by EAF, has been a major power quality concern for both power companies and customers. A model was developed for the electric arc furnace and it was applied in the simulation studies of distribution static synchronous compensator (DSTATCOM) for voltage flicker mitigation. The controller for DSTATCOM was designed based on DQ-model for the reactive power management which helps in the mitigation of …
Voltage And Power Quality Improvement Strategy For A Dfig Wind Farm During Variable Wind Conditions, L Meegahapola, T Littler, B Fox, J Kennedy, D Flynn
Voltage And Power Quality Improvement Strategy For A Dfig Wind Farm During Variable Wind Conditions, L Meegahapola, T Littler, B Fox, J Kennedy, D Flynn
Dr Lasantha G Meegahapola
This paper presents a voltage and power quality enhancement scheme for a doubly-fed induction generator (DFIG) wind farm during variable wind conditions. The wind profiles were derived considering the measured data at a DFIG wind farm located in Northern Ireland (NI). The aggregated DFIG wind farm model was validated using measured data at a wind farm during variable generation. The voltage control strategy was developed considering the X/R ratio of the wind farm feeder which connects the wind farm and the grid. The performance of the proposed strategy was evaluated for different X/R ratios, and wind profiles with different characteristics. …
Impact On Transient And Frequency Stability For A Power System At Very High Wind Penetration, Lasantha Meegahapola, Damian Flynn
Impact On Transient And Frequency Stability For A Power System At Very High Wind Penetration, Lasantha Meegahapola, Damian Flynn
Dr Lasantha G Meegahapola
This paper analyzes the impact on transient and frequency stability for a power system at very high wind penetration (40% wind). Wind penetration is based on the doubly-fed induction generator (DFIG), and a systematic approach has been adopted for wind power integration. A sensitivity analysis has been carried out for each wind integration scenario and for different wind generator loading conditions. A range of fault locations has been selected for stability analysis based on the proximity to synchronous generation and wind farms. The analysis has shown that transient stability performance is subject to fault location in the network, especially when …
Optimal Allocation Of Reactive Power Resources To Minimise Losses And Maintain System Security, Eknath Vittal, Lasantha Meegahapola, Damian Flynn, Andrew Keane
Optimal Allocation Of Reactive Power Resources To Minimise Losses And Maintain System Security, Eknath Vittal, Lasantha Meegahapola, Damian Flynn, Andrew Keane
Dr Lasantha G Meegahapola
Modern doubly-fed induction generator (DFIG) wind turbines have significant reactive power control capability, even during low wind speed conditions. This can improve system security by providing terminal voltage control at buses in the system. Generally, such control employs the full range of reactive power production from the turbine which can lead to increased system losses. By utilizing optimal power flow analysis, and limiting the range of reactive power production at certain wind farms, system losses can be minimized. If the reactive power of the wind farms are optimized to achieve the minimum system losses this may adversely affect the voltage …
Transient Stability Analysis Of A Power System With High Wind Penetration, Lasantha Meegahapola, Damian Flynn, Tim Littler
Transient Stability Analysis Of A Power System With High Wind Penetration, Lasantha Meegahapola, Damian Flynn, Tim Littler
Dr Lasantha G Meegahapola
This paper presents transient stability analysis for a power system with high wind penetration. The transient stability has been evaluated based on two stability criteria: rotor angle stability and voltage stability. A modified IEEE-14 bus system has been used as the main study network and simulations have been conducted at several wind power penetration levels, defined as a fraction of total system generation. A wide range of scenarios have been presented based on the wind farm voltage at the point of connection, i.e. low voltage (LV) distribution level and high voltage (HV) transmission level, and the type of wind generator …
Multi-Objective Reactive Power Support From Wind Farms For Network Performance Enhancement, Lasantha Meegahapola, Brendan Fox, Tim Littler, Damian Flynn
Multi-Objective Reactive Power Support From Wind Farms For Network Performance Enhancement, Lasantha Meegahapola, Brendan Fox, Tim Littler, Damian Flynn
Dr Lasantha G Meegahapola
This paper examines the ability of the doubly fed induction generator (DFIG) to deliver multiple reactive power objectives during variable wind conditions. The reactive power requirement is decomposed based on various control objectives (e.g. power factor control, voltage control, loss minimisation, and flicker mitigation) defined around different time frames (i.e. seconds, minutes, and hourly), and the control reference is generated by aggregating the individual reactive power requirement for each control strategy. A novel coordinated controller is implemented for the rotor-side converter and the grid-side converter considering their capability curves and illustrating that it can effectively utilise the aggregated DFIG reactive …
Voltage Security Constrained Reactive Power Optimization Incorporating Wind Generation, L G. Meegahapola, E Vittal, A Keane, D Flynn
Voltage Security Constrained Reactive Power Optimization Incorporating Wind Generation, L G. Meegahapola, E Vittal, A Keane, D Flynn
Dr Lasantha G Meegahapola
This paper presents a comparative analysis between conventional optimal power flow (OPF) and voltage constrained OPF strategies with wind generation. The study has been performed using the New England 39 bus system with 12 doublyfed induction generator (DFIG) based wind farms installed across the network. A voltage security assessment is carried out to determine the critical wind farms for voltage stability enhancement. The power losses and individual wind farm reactive power generation have been compared with and without voltage stability constraints imposed on the OPF simulation. It is shown that voltage constrained OPF leads to much greater active power losses …
Capability Curve Based Enhanced Reactive Power Control Strategy For Stability Enhancement And Network Voltage Management, Lasantha Meegahapola, Tim Littler, Sarath Perera
Capability Curve Based Enhanced Reactive Power Control Strategy For Stability Enhancement And Network Voltage Management, Lasantha Meegahapola, Tim Littler, Sarath Perera
Dr Lasantha G Meegahapola
Reactive power has become a vital resource in modern electricity networks due to increased penetration of distributed generation. This paper examines the extended reactive power capability of DFIGs to improve network stability and capability to manage network voltage profile during transient faults and dynamic operating conditions. A coordinated reactive power controller is designed by considering the reactive power capabilities of the rotor-side converter (RSC) and the grid-side converter (GSC) of the DFIG in order to maximise the reactive power support from DFIGs. The study has illustrated that, a significant reactive power contribution can be obtained from partially loaded DFIG wind …
Optimization Of Frt Active Power Performance Of A Dfig During Transient Grid Faults, L Meegahapola, Damian Flynn, Tim Littler
Optimization Of Frt Active Power Performance Of A Dfig During Transient Grid Faults, L Meegahapola, Damian Flynn, Tim Littler
Dr Lasantha G Meegahapola
Optimal fault ride-through (FRT) conditions for a doubly-fed induction generator (DFIG) during a transient grid fault are analyzed with special emphasis on improving the active power generation profile. The transition states due to crowbar activation during transient faults are investigated to exploit the maximum power during the fault and post-fault period. It has been identified that operating slip, severity of fault and crowbar resistance have a direct impact on the power capability of a DFIG, and crowbar resistance can be chosen to optimize the power capability. It has been further shown that an extended crowbar period can deliver enhanced inertial …
No Limits To Watching?, Katina Michael, M.G. Michael
No Limits To Watching?, Katina Michael, M.G. Michael
M. G. Michael
Little by little, the introduction of new body-worn technologies is transforming the way people interact with their environment and one another, and perhaps even with themselves. Social and environmental psychology studies of human-technology interaction pose as many questions as answers. We are learning as we go: 'learning by doing' through interaction and 'learning by being'. Steve Mann calls this practice existential learning; wearers become photoborgs, a type of cyborg (cybernetic organism) whose primary intent is image capture from the domains of the natural and artificial. This approach elides the distinction between the technology and the human; they coalesce into one.
No Limits To Watching?, Katina Michael, M.G. Michael
No Limits To Watching?, Katina Michael, M.G. Michael
Professor Katina Michael
Little by little, the introduction of new body-worn technologies is transforming the way people interact with their environment and one another, and perhaps even with themselves. Social and environmental psychology studies of human-technology interaction pose as many questions as answers. We are learning as we go: 'learning by doing' through interaction and 'learning by being'. Steve Mann calls this practice existential learning; wearers become photoborgs, a type of cyborg (cybernetic organism) whose primary intent is image capture from the domains of the natural and artificial. This approach elides the distinction between the technology and the human; they coalesce into one.
Agent-Based Demand Management In A Power Distribution Network By Considering Distributed Generations, Fenghui Ren, Minjie Zhang, Danny Soetanto
Agent-Based Demand Management In A Power Distribution Network By Considering Distributed Generations, Fenghui Ren, Minjie Zhang, Danny Soetanto
Dr Fenghui Ren
A distribution network carries electricity from transmission network to consumers through facilities such as substations, buses and feeders. Distributed generations emerge as the new alternative power resource to a distribution network at a smaller and distributed scale. On one hand, distributed generations can decrease substations' load and power price. On the other hand, they will bring difficulties to substations for demand management. This paper proposes a multiagent model to represent a radial distribution network. The model includes five types of agents, which are substation agents, bus agents, feeder agents, load agents and generation agents. Through communicating with neighbouring agents, each …
A Multiagent Approach For Decentralized Voltage Regulation In Power Distribution Networks Within Dgs, Fenghui Ren, Minjie Zhang, Danny Sutanto
A Multiagent Approach For Decentralized Voltage Regulation In Power Distribution Networks Within Dgs, Fenghui Ren, Minjie Zhang, Danny Sutanto
Dr Fenghui Ren
Voltage regulation (VR) is a procedure to keep voltages in a distribution network (DN) within normal limits. Conven- tionally, a voltage regulator can read voltage levels from pre- dened measures, and regulate the voltages. However, due to lacking of a distributed generator's (DG) information, the unexpected electricity from a DG will mislead readings on voltages levels, so as to disturb the VR in a DN. Adjust- ing a DG's reactive power output is an alternative way for VR. However, because of limited penetration levels, DGs need to collaborate with other devices in order to provide an eective voltage regulation. Therefore, …
Multi-Objective Reactive Power Support From Wind Farms For Network Performance Enhancement, Lasantha Meegahapola, Brendan Fox, Tim Littler, Damian Flynn
Multi-Objective Reactive Power Support From Wind Farms For Network Performance Enhancement, Lasantha Meegahapola, Brendan Fox, Tim Littler, Damian Flynn
Faculty of Engineering and Information Sciences - Papers: Part A
This paper examines the ability of the doubly fed induction generator (DFIG) to deliver multiple reactive power objectives during variable wind conditions. The reactive power requirement is decomposed based on various control objectives (e.g. power factor control, voltage control, loss minimisation, and flicker mitigation) defined around different time frames (i.e. seconds, minutes, and hourly), and the control reference is generated by aggregating the individual reactive power requirement for each control strategy. A novel coordinated controller is implemented for the rotor-side converter and the grid-side converter considering their capability curves and illustrating that it can effectively utilise the aggregated DFIG reactive …
A Multiagent Approach For Decentralized Voltage Regulation In Power Distribution Networks Within Dgs, Fenghui Ren, Minjie Zhang, Danny Sutanto
A Multiagent Approach For Decentralized Voltage Regulation In Power Distribution Networks Within Dgs, Fenghui Ren, Minjie Zhang, Danny Sutanto
Faculty of Engineering and Information Sciences - Papers: Part A
Voltage regulation (VR) is a procedure to keep voltages in a distribution network (DN) within normal limits. Conven- tionally, a voltage regulator can read voltage levels from pre- dened measures, and regulate the voltages. However, due to lacking of a distributed generator's (DG) information, the unexpected electricity from a DG will mislead readings on voltages levels, so as to disturb the VR in a DN. Adjust- ing a DG's reactive power output is an alternative way for VR. However, because of limited penetration levels, DGs need to collaborate with other devices in order to provide an eective voltage regulation. Therefore, …
Capability Curve Based Enhanced Reactive Power Control Strategy For Stability Enhancement And Network Voltage Management, Lasantha Meegahapola, Tim Littler, Sarath Perera
Capability Curve Based Enhanced Reactive Power Control Strategy For Stability Enhancement And Network Voltage Management, Lasantha Meegahapola, Tim Littler, Sarath Perera
Faculty of Engineering and Information Sciences - Papers: Part A
Reactive power has become a vital resource in modern electricity networks due to increased penetration of distributed generation. This paper examines the extended reactive power capability of DFIGs to improve network stability and capability to manage network voltage profile during transient faults and dynamic operating conditions. A coordinated reactive power controller is designed by considering the reactive power capabilities of the rotor-side converter (RSC) and the grid-side converter (GSC) of the DFIG in order to maximise the reactive power support from DFIGs. The study has illustrated that, a significant reactive power contribution can be obtained from partially loaded DFIG wind …
A Three-Phase Power Flow Approach For Integrated 3-Wire Mv And 4-Wire Multigrounded Lv Networks With Rooftop Solar Pv, Md J E Alam, K M. Muttaqi, Darmawan Sutanto
A Three-Phase Power Flow Approach For Integrated 3-Wire Mv And 4-Wire Multigrounded Lv Networks With Rooftop Solar Pv, Md J E Alam, K M. Muttaqi, Darmawan Sutanto
Faculty of Engineering and Information Sciences - Papers: Part A
With increasing level of rooftop solar photovoltaic (PV) penetration into low voltage (LV) distribution networks, analysis with realistic network models is necessary for adequate capturing of network behavior. Traditional three-phase 3-wire power flow approach lacks the capability of exact analysis of 4-wire multigrounded LV networks due to the approximation of merging the neutral wire admittance into the phase wire admittances. Such an approximation may not be desirable when neutral wire and grounding effects need to be assessed, especially in the presence of single-phase solar power injection that may cause a significant level of network unbalance. This paper proposes a three-phase …
A Unique Sandwich-Structured C/Ge/Graphene Nanocomposite As An Anode Material For High Power Lithium Ion Batteries, Dan Li, Kuok H. Seng, Dongqi Shi, Zhixin Chen, Hua-Kun Liu, Zaiping Guo
A Unique Sandwich-Structured C/Ge/Graphene Nanocomposite As An Anode Material For High Power Lithium Ion Batteries, Dan Li, Kuok H. Seng, Dongqi Shi, Zhixin Chen, Hua-Kun Liu, Zaiping Guo
Faculty of Engineering and Information Sciences - Papers: Part A
A unique sandwich-structured C/Ge/graphene composite with germanium nanoparticles trapped between graphene sheets is prepared by a microwave-assisted solvothermal reaction followed by carbon coating and thermal reduction. The graphene sheets are found to be effective in hindering the growth and aggregation of GeO2 nanoparticles. More importantly, the graphene sheets, coupled with the carbon coating, can buffer the volume changes of germanium in electrochemical lithium reactions. The unique sandwich structure features a highly conductive network of carbon, which can improve both the conductivity and the structural stability of the electrode material, and exemplifies a promising strategy for the development of new high …
Transmit Antenna Subset Selection With Power Balancing For High Data Rate Mimo-Ofdm Uwb Systems, Ngoc Phuc Le, Le Chung Tran, Farzad Safaei
Transmit Antenna Subset Selection With Power Balancing For High Data Rate Mimo-Ofdm Uwb Systems, Ngoc Phuc Le, Le Chung Tran, Farzad Safaei
Faculty of Engineering and Information Sciences - Papers: Part A
This paper proposes per-subcarrier transmit antenna subset selection with power balancing for MIMO-OFDM UWB systems to simultaneously improve the system error performance and increase data rates. The deployment of the per-subcarrier antenna subset selection may result in a power unbalance across antennas, which could cause power amplifiers (PAs) to operate in their non-linear regions. To overcome this disadvantage, we formulate a linear optimization problem for the optimal allocation of data subcarriers under a constraint that all antennas have the same number of assigned data symbols. This optimization problem could be applied to systems with an arbitrary number of multiplexed data …
Characteristics Of Power Quality Disturbances In Australia: Voltage Harmonics, S T. Elphick, V W. Smith, V J. Gosbell, S Perera
Characteristics Of Power Quality Disturbances In Australia: Voltage Harmonics, S T. Elphick, V W. Smith, V J. Gosbell, S Perera
Faculty of Engineering and Information Sciences - Papers: Part A
Management of harmonic voltage levels can impose significant economic impacts for both electricity suppliers and customers. For the case where harmonic voltage levels are high, economic costs include damage to equipment and associated loss of production due to high voltage harmonic levels as well as the costs associated with mitigation of harmonic currents, for example, harmonic filters. In the alternate scenario, ie. the case where harmonic voltage levels are acceptable, considerable expense may be incurred mitigating harmonic currents unnecessarily due to lack of knowledge of harmonic levels and/or network capabilities. As such, there is considerable potential for industry to make …