2020 International SAUPEC/RobMech/PRASA Conference最新文献

{"title":"Available Transfer Capability Enhancement with FACTS: Perspective of Performance Comparison","authors":"B. O. Adewolu, A. Saha","doi":"10.1109/SAUPEC/RobMech/PRASA48453.2020.9040995","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA48453.2020.9040995","url":null,"abstract":"Static Var Compensator (SVC) and Thyristor Controlled Series Compensator (TCSC) models were incorporated into Newton Raphson power flow equations for enhancement of available transfer capability (ATC) of a deregulated power network in this study. Bus voltage profile improvement and real power loss minimization were considered as part of objectives and were investigated during ATC enhancement. The performance of the duo based on these objectives were analytically compared. IEEE 30 bus network system was used for these comparative analyses and the implementation was done in Matlab environment. Real power loss minimization of up to 0.06 MW and voltage improvement of bus 21 to 30 were achieved with SVC, while ATC enhancement of up to 14% were recorded for both devices. ATC values, bus voltage magnitude profile and transmission line real power losses suggested an advantage of SVC over TCSC for ATC enhancement deployment.","PeriodicalId":215514,"journal":{"name":"2020 International SAUPEC/RobMech/PRASA Conference","volume":"18 11","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120887929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Statistical Assessment of Potential Wind Energy Sites in Coastal and Southern Part of Namibia","authors":"Edwin Tareka, S. Chowdhury","doi":"10.1109/SAUPEC/RobMech/PRASA48453.2020.9040966","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA48453.2020.9040966","url":null,"abstract":"This paper presents an outlined detail on wind resource assessment for the potential of onshore wind energy in Namibia. Wind speed data collected from Namibia Energy Institute (NEI) measured from five masts located in the coastal and southern areas of the country were analyzed using statistical methods incorporated in MATLAB and Microsoft Excel. The statistical data analysis involved carrying out wind energy and power estimation, performing wind speed interpolation (60m-200m) and plot wind speed on an annual, monthly and seasonal basis. The analysis also involved performing statistical data fitting by Weibull distribution using various Weibull methods, plotting of wind rose diagrams and finally, carrying out capacity factor calculations. Comparison of all sites under study were done based on the analysis and the suitable location with good energy yield was recommended. Wind turbine generator power curve of enough capacity was used to assess the predicted operation under the wind climatic condition determined from data analysis for all studied sites.","PeriodicalId":215514,"journal":{"name":"2020 International SAUPEC/RobMech/PRASA Conference","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115779184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optical Monitoring of Pollution on MV Bushings","authors":"F. Fernandes, J. Van Coller, N. Mahatho","doi":"10.1109/SAUPEC/RobMech/PRASA48453.2020.9040927","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA48453.2020.9040927","url":null,"abstract":"The proposed research aims to optically monitor the dry pollution level on transformer bushings and determine the possible leakage current should the dry polluted surface be critically wetted. The research involves the implementation of an image capturing system with appropriate image processing. A lighting array that surrounds the camera, required for one of the imaging techniques, is designed and implemented. Calibration of light position data of the array is detailed. The HV test setup used to acquire leakage current and the methods used to determine bushing pollutant conductivity are presented. The relationship between Equivalent Salt Deposit Density (ESDD) and leakage current is shown to have a logarithmic fitting, as expected from the SANS 60815 grading of pollution severity. The leakage current is characterised at various known pollution levels under wetted conditions as a reference for the neural network to correlate the predicted dry pollution level (from the images) to leakage current under wetted conditions (from test measurements). An example data-set, linking leakage current, conductivity, salinity, pollutant surface coverage and saliency, and ESDD is presented. Furthermore, the methodology relating to implementation and verification is outlined. The standard methods used to classify pollution types and severity are discussed. A brief overview of the dynamics governing bushing flashover under polluted conditions is presented. The actual pollution level and type is quantified using ESDD and Non-Soluble Deposit Density (NSDD). Image segmentation and border extraction are illustrated to output four variables related to surface pollutants: area ratio, coverage, shape factor and eccentricity. The first two parameters are proposed as measures of surface pollution density, while the latter two may assist in pollution type identification. For more accurate pollution type identification, reflectance transformation imaging (RTI) is used. With a saliency mapping resolution of approximately 100 µm, the feature recognition between salt deposits and dust deposits is more readily attained.","PeriodicalId":215514,"journal":{"name":"2020 International SAUPEC/RobMech/PRASA Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128448406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Successes in University - Industry Partnerships - Perspectives from Durban University of Technology","authors":"I. Davidson","doi":"10.1109/SAUPEC/RobMech/PRASA48453.2020.9041128","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA48453.2020.9041128","url":null,"abstract":"The Higher Education Partnerships project in Sub Saharan Africa funded by the British Royal Academy of Engineering, which ran from April 2017 to March 2019. It is a network of engineering faculties and schools from the Hub University (Lead University) - University of Namibia (UNAM), UK Partner University - University of Cambridge; and three Spoke Universities (Satellite universities): Durban University of Technology, University of Nairobi Kenya and the University of Addis Ababa, with the aim of enhancing quality engineering education and training. This paper presents the outcomes of the project, namely: graduate engineers and technicians who meet the expectations of modern industry and engineering professional bodies; and are relevant and therefore employable nationally and regionally; academic and technical staff with enhanced practical experience and better teaching skills, and enriched and relevant engineering curriculum at universities.","PeriodicalId":215514,"journal":{"name":"2020 International SAUPEC/RobMech/PRASA Conference","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127241422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Automating predictive maintenance using oil analysis and machine learning","authors":"Sarah Keartland, Terence L van Zyl","doi":"10.1109/SAUPEC/RobMech/PRASA48453.2020.9041003","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA48453.2020.9041003","url":null,"abstract":"Predictive maintenance aims to reduce costly and time consuming repairs, and also avoid unnecessary activities by proposing a maintenance strategy that is informed by machine condition monitoring. The majority of mechanical systems are oil lubricated, therefore oil analysis provides a rich source of machine condition data for many mechanical systems. This research investigates the use of random forests, feed-forward neural networks and logistic regression models trained using oil analysis data for classifying machine conditions. The RF model outperformed the other classifiers for all machine conditions. The interpretation of the feature importance for the RF models were found to be consistent with industry knowledge, demonstrating the potential use of RF as a diagnostic tool in predictive maintenance.","PeriodicalId":215514,"journal":{"name":"2020 International SAUPEC/RobMech/PRASA Conference","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116872305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Partial Discharge Magnitude Variation with Voltage in Single Cavity and Double Cavities","authors":"I. Kyere, C. Nyamupangedengu, J. Walker","doi":"10.1109/SAUPEC/RobMech/PRASA48453.2020.9041034","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA48453.2020.9041034","url":null,"abstract":"In this paper a comparative study of cavity defects partial discharge in single and double cavities was performed at different applied voltages. The variation of the PD magnitudes and phase-resolved-patterns (PDPRP) are studied as a function of increasing supply voltage magnitude. The study is conducted on polymer insulation discs. Two test samples were prepared. Sample 1 consist of a cavity of 0.1 mm thickness and sample 2 with 2 of 0.1 mm cavities positioned 0.1 mm apart in the middle of the insulation. The PD magnitude of the double voids are affected significantly by the increase in applied voltage compared to the single cavity magnitude. The PDPRP however are invariant. An electric field simulation model was created using QuickField Software to investigate the electric field distribution profiles in the insulation model. The simulation results correlated with the measurement results.","PeriodicalId":215514,"journal":{"name":"2020 International SAUPEC/RobMech/PRASA Conference","volume":"19 8","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113972066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A System Based Protection Test Solution for Eskom Sub-Transmission Lines","authors":"E. Raubenheimer, T. S. Hlalele, A. Yusuff","doi":"10.1109/SAUPEC/RobMech/PRASA48453.2020.9041000","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA48453.2020.9041000","url":null,"abstract":"The failure of protection schemes for subtransmission lines has been a major cause of loss of power supply due to incorrect relay settings, and communication assisted tripping errors. Settings based on testing methods are utilised to verify protection scheme. However, these methods focus mainly on the accuracy of protection relays and the functionality of the scheme. Due to the complexity of protection schemes, verifying the functionality based on future predictions in the actual network is pivotal. The amount of settings and configurations need to be done are tremendous. In this paper the actual network parameters are used to build admittance bus matrix in excel sheet, calculate fault currents and injects them into a protection scheme using the Omicron CMC test set. The results show that relay accuracy test can be performed more effectively and the entire scheme can be tested, monitored and evaluated better; thus improves network reliability.","PeriodicalId":215514,"journal":{"name":"2020 International SAUPEC/RobMech/PRASA Conference","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116828547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"3D Pose Estimation and Tracking of an Electricity Pylon","authors":"Emmanuel Y. Ali, F. Nicolls","doi":"10.1109/SAUPEC/RobMech/PRASA48453.2020.9041094","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA48453.2020.9041094","url":null,"abstract":"We demonstrate an algorithm for estimating the 6 degree-of-freedom pose of a textureless object such as a power pylon. The method is designed to be part of the inspection process for a transmission line. The approach involves three steps, namely predicting the vertices of the pylon with a neural network, establishing the correspondence between vertices with hashing techniques, and incrementally tracking the movement of the camera. We built a pylon model for the experiments and used it to generate our dataset.","PeriodicalId":215514,"journal":{"name":"2020 International SAUPEC/RobMech/PRASA Conference","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116860795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Balancing between Demand and Trading in Microgrids","authors":"M. Gomba, R. Chidzonga, Bahe Nleya, Philani M. Khumalo","doi":"10.1109/SAUPEC/RobMech/PRASA48453.2020.9041018","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA48453.2020.9041018","url":null,"abstract":"The envisaged future generation power or smart grid (SG) will incorporate ICT technologies as well as innovative ideas for advanced integrated and automated power systems. The bidirectional information and energy flows within the envisaged advanced SG together with other aiding devices and objects, promote a new vision to energy supply and demand response. Meanwhile, the gradual shift to the next generation fully fledged SGs will be preceded by individual isolated microgrids voluntarily collaborating in the managing of all the available energy resources within their control to optimally serve both demand and distribution. In so doing, innovative applications will emerge that will bring numerous benefits as well as challenges in the SG. This paper introduces a power management approach that is geared towards optimizing power distribution, trading, as well as storage among cooperative microgrids (MGs). The initial task is to formulate the problem as a convex optimization problem and ultimately decompose it into a formulation that jointly considers user utility as well as factors such as MG load variance and associated transmission costs. It is deduced from obtained analytical results that the formulated generic optimization algorithm characterizing both aggregated demand and response from the cooperative microgrids assist greatly in determining the required resources hence enabling operational cost viability of the entire system.","PeriodicalId":215514,"journal":{"name":"2020 International SAUPEC/RobMech/PRASA Conference","volume":"261 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115564266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transformer models and meters in MATLAB and PSCAD for GIC and leakage dc studies","authors":"Pitambar Jankee, H. Chisepo, Victor Adebayo, D. Oyedokun, C. T. Gaunt","doi":"10.1109/SAUPEC/RobMech/PRASA48453.2020.9041060","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA48453.2020.9041060","url":null,"abstract":"Geomagnetically induced currents (GIC) caused by abnormal space weather have traditionally been modelled as balanced dc in low-frequency transients studies. Existing transformer models can be used to investigate a power system with GIC but the extent to which these models are consistent is unclear. This paper investigated the differences between the three-phase five limb (3p5L) power transformer models in MATLAB Simulink and PSCAD/EMTDC when they were subjected to dc (dcGIC) and low-frequency GIC (acGIC). The simulation protocol used a simple 4-bus power system with a generator, two transformers, a line, and a PQ load. An IEEE 1459 power calculation block was developed in MATLAB for non-ideal conditions whereas waveform data was post-processed from the PSCAD simulations. The results showed that even though the transformer models were calibrated with the same magnetization characteristics, the 3p5L PSCAD models with inter-phase magnetic coupling yielded a slightly different magnetization curve for each phase. By contrast, the MATLAB model yielded the same magnetization curve for each phase under the same conditions. As a result, there were differences in the performance with dc or acGIC, with the PSCAD model being more responsive to phase unbalance, simulating greater distortion in the transmission line, and voltage drop at the end.","PeriodicalId":215514,"journal":{"name":"2020 International SAUPEC/RobMech/PRASA Conference","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125038522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}