EECon - 2016
Permanent URI for this collectionhttp://192.248.9.226/handle/123/17337
Browse
Browsing EECon - 2016 by Title
Now showing 1 - 18 of 18
- Results Per Page
- Sort Options
- item: Conference-Full-text1st International Conference on Electrical Engineering 2016 (Pre Text)(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Rajapakse, A; Prasad, WD
- item: Conference-Full-textComparison of techniques based on current signature analysis to fault detection and diagnosis in induction electrical motors(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Fontes, AS; Cardoso, CAV; Oliveira, LPB; Rajapakse, A; Prasad, WDThe wide use of electrical induction motors in industries throughout the world requires, increasingly, more precision in fault diagnosis. Techniques of predictive maintenance such as Motor Current Signature Analysis (MCSA) and Motor Current Square Signature Analysis (MSCSA) are used to detect and diagnose faults patterns, characterized by the stator current spectrum, in induction motors. In this article, these techniques are applied and compared for different faults in real motors, such as inter-turn short circuit in the stator winding and eccentricity in the air gap. To assist in the comparison of these patterns of the stator current spectrum with and without faults, a theoretical model of a healthy electrical induction motor was used, with the same values of the real supply voltages, which generated the frequency spectrum patterns. The results presented in this article, which should be emphasized, demonstrated that the techniques mentioned above were suitable for the cited faults, whose comparison between the techniques showed the suitability of each one.
- item: Conference-Full-textDC microgrid as a solution for utilisation of solar photovoltaic sources(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Bandara, AIMH; Binduhewa, P; Ekanayake, J; Rajapakse, A; Prasad, WDMicroGrid (MG) is a convenient solution to integrate renewable energy sources to the existing power network. Though ac MicroGrids are widely studied, researches are focused towards the implementation of dc MicroGrids in order to improve the utilization of renewable sources with dc power output. In this study a MicroGrid architecture for commercial buildings and domestic houses with solar photovoltaic (PV) as the renewable energy source is proposed. The dc MicroGrid was implemented in PSCAD/EMTDC software package and simulations studies were conducted to validate the operation.
- item: Conference-Full-textDevelopment of a test platform for synchrophasor applications with real-time digital simulator(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Gurusinghe, DR; Rajapakse, AD; Rajapakse, A; Prasad, WDThe rapid advance of synchrophasor technology and the growth of phasor measurement unit (PMU) installations in the recent years have substantially increased the feasibility of deploying practical synchrophasor applications. These novel applications need to be thoroughly evaluated before their actual implementations on real power systems. The most feasible solution is to use real-time power system simulators. Therefore, this paper presents a real-time digital simulator (RTDS) based test platform to implement and to validate various synchrophasor applications range from simple monitoring algorithms to advanced response based wide area monitoring, protection and control systems. The proposed test platform can also be used to validate PMU performances as well as to assess cyber-security issues of synchrophasor networks. The effectiveness of the test platform is demonstrated with a real-time monitoring application.
- item: Conference-Full-textDevelopment of an automated microscopic imaging system for TB screening(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Samarasinghe, HDTG; Sampath, LLR; Thilakarathna, HRMMVB; Gopura, RARC; Lalitharatne, TD; Amarasinghe, YWR; Rajapakse, A; Prasad, WDThis paper proposes an automated microscopic imaging system (MIS) for TB screening. Mainly, the system consists of integrated hardware and software components for sputum smear slides feeding, controlling and carrying out microscopic and image processing functions of the system. The MIS is used to distinguish TB positive and negative cases. The hardware system and controlling mechanism of MIS are discussed. Algorithms for focusing of the microscope and image processing are presented. Experiments are carried out to evaluate the proposed automated microscopic imaging system
- item: Conference-Full-textEvaluation of the impact of integrating pumped-storage systems in a small power system with high wind penetration(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Peiris, KRD; Kalpage, KMT; Perera, KAIRP; Wickramarathna, MTAP; Siriwardana, MGCI; Lidula, NWA; Rajapakse, A; Prasad, WDHigh wind penetration in a small power system can create overwhelming stability issues at contingencies. Hybrid wind and pumped-storage systems are widely adopted to harness the maximum wind energy potential locally. Similarly, integration of pumped-storage power plants can be considered for islands or small power systems to integrate more wind farms while improving stability of the system. A small power system was derived based on the IEEE-12 bus system to evaluate the system behavior with increased wind penetration and pumped-storage integration. The integrated system was simulated in PSCAD/EMTDC to analyze the system transient stability under different scenarios. The studies revealed that the integration of pumped-storage systems into small power systems with high wind penetration not only supports more wind penetration into the system but also improves the transient stability.
- item: Conference-Full-textFactor analysis, hessian local linear embedding and isomap for epilepsy classification from EEG(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Prabhakar, SK; Rajaguru, H; Rajapakse, A; Prasad, WDIn this present generation, more than 1% of the whole world’s population is affected by this seizure disorder. Due to genetic predispositions like tumours, strokes and drug misuse, epilepsy is caused. Epilepsy is a common brain disorder in which cluster of neuronal signals function abnormally. For preventing seizures, medications are available but only some patients can respond well to the medication. Other remedial measures such as neurostimulation, surgery, maintaining a healthy diet are not always successful in treating the patient. Because of epilepsy, the patients have to live with persistent anxiety throughout their lives and also leading a normal life and performing day to day and social tasks becomes more difficult for them. For the analysis and diagnosis of epilepsy, the detection and classification of seizures forms the most important step. The vital information regarding the dynamics of the brain can be easily measured by Electroencephalogram (EEG). Since the recordings of the EEG data are pretty long, the obtained data is too huge to process and so, in this study, the dimension of the EEG data is reduced by Dimensionality Reduction (DR) techniques such as Factor Analysis (FA), Hessian Local Linear Embedding (HLLE) and Isomap (IM). The dimensionally reduced values are then classified with the help of Genetic Algorithm (GA) and Generalized Regression Neural Network (GRNN). The performance metrics are analyzed with parameters such as performance index, sensitivity, specificity, time delay, quality value and accuracy. The results show that when FA, HLLE and Isomap are classified with GRNN, then a perfect classification of 100% and an accuracy of 100% are obtained. If the dimensionality reduction techniques classified with GA are compared, then a high accuracy of 95.24% is obtained when it is classified with HLLE-GA combination.
- item: Conference-Full-textThe impact of distributed generation on transmission and distribution losses in Sri Lankan power system(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Priyangika, AAC; Wijayapala, WDAS; Banda, HMW; Rajapakse, A; Prasad, WDShare of Non-Conventional Renewable Energy (NCRE), small hydro, wind, solar, bio-mass etc based electricity generation in Sri Lanka at present is 10% of the total annual generation. The Government of Sri Lanka has declared a national target of 20% from NCRE by 2020[1]. Most of NCRE power plants have been connected to the distribution network and are termed as Distributed Generators (DGs). With the increase of share of DGs, it affects system reliability, power quality and economic operation of the distribution network. This paper focuses on the impact of economic operation of transmission and distribution network due to distributed generation in Sri Lankan power system. Network simulation studies have been carried out for transmission network and for four grid substations to which many DGs have been connected. The analysis revealed that transmission network losses have reduced with increase penetration of DGs to the system while distribution network losses are dependent on the amount of DG capacities connected to the distribution network. However, there is a reduction of network losses when overall network is considered thereby giving financial benefit from DGs added to the system.
- item: Conference-Full-textLocal detection of distribution level faults in a distributed sensor monitoring network using HMM(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Balachandran, T; Aravinthan, V; Thiruvaran, T; Rajapakse, A; Prasad, WDThe Smart distribution system initiative requires an increased usage of the distribution feeder-level communication infrastructure to improve automation. Using a distributed sensor network for monitoring the distribution system is proposed by various researchers. Such distributed sensor communication architecture requires information to be received within an allowable delay and a minimum processing time at the control center. Increasing the number of sensors in the network also increases the data flow in the communication medium. Therefore, to reduce the burden in the communication medium, an event driven communication protocol could be utilized. This communication architecture assumed that the sensors used a local fault detection system to detect the abnormal event before communicating with the control center. This work focusses on local detection of faults in a distributed sensor network using a Hidden Markov Model considering a minimum processing time.
- item: Conference-Full-textMainstreaming renewable energy developments into traditional planning: a Sri Lanka case study(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Chathuranga, JHKK; Wijayapala, WDAS; Wijayatunga, PDC; Rajapakse, A; Prasad, WDThis study examines the Sri Lankan generation planning practices and recommends several methodological changes and models to successfully integrate and evaluate Non-Conventional Renewable Energy (NCRE) resources in the present planning approaches. The paper proposes the peak period capacity factor method to calculate the capacity credit of NCRE generation. A methodology is presented to model a wind power plant in Wien Automatic System Planning Package IV (WASP IV) and also to evaluate the benefits of modeled NCRE plants. The Mean Variance Portfolio Theory (MVPT) is proposed as a complementary planning tool to assess the risks of generation portfolios and finally, these concepts are applied on the Sri Lankan system to demonstrate the applicability.
- item: Conference-Full-textMapping and path planning for long distance autonomous navigation using multisensory data(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Weerasinghe, KKDKU; Silva, LCJ; Basnayake, BMSS; Sandanayaka, SDM; Kumarawadu, SP; Chandima, DP; Jayasekara, AGBP; Rajapakse, A; Prasad, WDThis paper presents a methodology and a concept behind the autonomous navigation which can be used in field robots. Long distance navigation in an outdoor environment is a challenging task owing to floor profile variations and slipping problem. The concept is based on SLAM (Simultaneous Localization and Mapping) GMapping algorithm with particle filter approach in mapping process and AMCL (Adaptive Monte Carlo Localization) in navigation process. Experimental results are presented in this paper with the implementation of mobile robot platform using ROS (Robot Operating System). Further, reasons for the errors and methodology to overcome the problems are proposed.
- item: Conference-Full-textA novel mathematical model to improve the power output of a solar panel using reflectors(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Wijesuriya, DTP; Wijesinghe, LS; Wickramathilaka, KDSH; Vithana, DM; Perera, HYR; Rajapakse, A; Prasad, WDSri Lanka is located in an ideal position in the world map to harness more solar power compared to the countries situated away from the equator. Yet, Sri Lanka has been unable to gain the maximum advantage out of it due to the lower usage of solar harnessing systems partially due to the higher pay back periods of imported solar panels. The main purpose of this study is to optimize the electrical power output of a Solar Panel in a more cost effective method than solar tracking. In this research a novel mathematical model is presented for optimizing the positioning of fixed flat reflectors to enhance the solar insolation on a silicon based solar module throughout the day. The effect on the electrical energy output due to the increment of the solar insolation and the operating temperature is mainly considered in this research.
- item: Conference-Full-textOptimization of the usage of Samanalawewa water resource for power generation(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Pathiraja, MPW; Wijayapala, WDAS; Rajapakse, A; Prasad, WDSamanalawewa hydropower project includes a reservoir, a water way system and a 120MW power plant as the stage I development. Some provisions have been kept for stage II development to add another 120MW power plant to operate as a peak serving power plant. Since the impounding of the reservoir, there is a water leak which causes more than one fifth of energy loss of the current energy generation by Samanalawewa power plant. The construction of stage II is suspended with lower energy generation due to the leak. This research discusses about a Leak Pump Back System which will curtail the net water outflow from the leak. The leaked water pumping head is much lower than the design head of Samanalawewa power plant, resulting in high net energy gain. Since the pumped back water is regulated by the reservoir, the extra energy generation is dispatchable. This will further improve the feasibility of Samanalawewa stage II development. Currently Samanalawewa mini-hydropower plant is operating using the leaked water. The mini hydro plant can recover less than one third of energy which could be recovered by leak pump back system. Therefore the combined operation of mini hydro and leak pump back system will give more benefits, though the leak pump back system is going to limit the water supply to the mini hydro plant.
- item: Conference-Full-textPotential for promotion of demand side management in Sri Lanka through a market based approach(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Karunadasa, JP; Siyambalapitiya, T; Hemachandra, EAEH; Rajapakse, A; Prasad, WDToday with the developments in technology, expansion and developments in industries, and increase in the standard of living of the society, the demand for electricity keeps rising every day. It is the responsibility of the utility to increase its supply to meet this demand in order maintain the demand supply balance. It is not always economical to meet this increasing demand by building new power plants. Hence today, more interest is shown towards controlling the demand, through Demand Side Management (DSM). Several customer categories in Sri Lanka were studied in order to identify the potential DSM options that can be implemented. The selected option was Chilled Water Storage (CWS) in buildings, by constructing storage tanks to store chilled water during the off-peak period, and using the stored chilled water to meet the peak-time cooling demand. The technical potential for savings that can be obtained through this technology in Sri Lankan context is analyzed, and the potential saving that can be achieved in the General Purpose and Hotel category customer group is calculated.
- item: Conference-Full-textSmart irrigation controlling system for green roofs based on predicted evapotranspiration(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Bandara, AGN; Balasooriya, BMAN; Bandara, HGIW; Buddhasiri, KS; Muthugala, MAVJ; Jayasekara, AGBP; Chandima, DP; Rajapakse, A; Prasad, WDA green roof is a roof of a building that is covered from a vegetation. Green roofs are beneficial in number of ways for buildings. Crops in green roofs are exposed to direct solar radiation and strong winds. Furthermore, the substrate is shallow and it can hold limited amount of water. Therefore, artificial irrigation methods are required especially for green roofs in tropical countries. This paper proposes a novel irrigation controlling method for green roof based on predicted evapotranspiration. The system is capable of predicting the evapotranspiration and deciding the amount of water to be irrigated based on that. The rationale behind the proposed method is also explained. Particulars on designing and developing a prototype irrigation controller and a laboratory test bed for experimenting with green roofs are presented. Experiments have been carried out and the experimental results are discussed in order to analyze the performance of the proposed system. The experimental results validate the applicability of the proposed system.
- item: Conference-Full-textSub-system based reliability assessment for distribution transformer(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Rahman, MRU; Aravinthan, V; Rajapakse, A; Prasad, WDImplementation of Smart Grid into the power system has made our grid more robust and reliable. Due to integration of two-way, real time communication it is possible to monitor equipment through sensors. Continuous monitoring will help to predict the state of the equipment. Due to this fact and also to ensure the system performance, time based maintenance can be replaced by condition or reliability based maintenance. Contribution of this work is to identify the appropriate standards for to be used for the transformer subcomponents and develop appropriate Weibull distribution parameters for each subcomponent for a modified series-parallel topology of distribution transformer. This modification is done based on the available measurements and standards. Using the developed reliability model, Monte Carlo simulation was performed to evaluate the behavior of these parameters.
- item: Conference-Full-textTechno-economic feasibility of using 400 kV for the 2032 transmission system of Sri Lanka(Institute of Electrical and Electronics Engineers, Inc., 2016-12) Alahendra, GB; Banda, HMW; Lidula, NWA; Rajapakse, A; Prasad, WDCongestion occurs on the nation’s electric transmission grids with the addition of new generation to meet the increasing electricity demand. Therefore, reliable, efficient and better quality of supply urge introduction of new higher voltage levels for power transmission. However, it has to be technically feasible and economically justifiable for the country. Technical feasibility and economic justification of introducing a higher voltage than that of existing voltage to transmit bulk power to load centers from bulk power generating stations in Sri Lanka is discussed in detail in this research.
- item: Conference-Full-textThree phase asymmetrical power flow algorithm using current injection technique(Institute of Electrical and Electronics Engineers, Inc., 2016-12) De Vas Gunawardena, APSG; Ranatunga, NT; Samarathunga, LL; Weerawansha, SDT; Jayatunga, U; Rajapakse, A; Prasad, WDLoad flow studies play a vital role in planning the future expansion of power system as well as for deciding the optimum operation of the existing power system. Three phase asymmetrical power flow studies are recommended for unbalanced power systems such as distribution networks. Unbalanced loading, single phase and two phase shunts make the system operation unbalanced leaving the application of conventional load flow techniques away from the scene. The paper presents an unbalanced power flow algorithm based on the current injection technique with full Newton-Raphson formulation. The proposed method is validated using IEEE four bus test network.