2021 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)最新文献

{"title":"A front-end technique for visual gold detection and localization – Towards automation of the gold panning process.","authors":"Blessing Chipfurwe Makoni, M. Namoshe, O. Matsebe","doi":"10.1109/SAUPEC/RobMech/PRASA52254.2021.9377246","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA52254.2021.9377246","url":null,"abstract":"To do away with the time consuming, error prone and expert dependent gold detection and localization in the current gold panning procedure, automatic image-based techniques are considered in this paper. Identifying and locating gold particles during the gold panning process is a fundamental process in gold extraction. In the automation of the gold panning process and robotic handling it is important to identify and locate the gold particles in the images captured by the image sensor. Image segmentation is a vital step in image simplification, image understanding and object detection. Image segmentation is the process of identifying and extracting homogeneous regions (segments) in an image satisfying a homogeneity criterion based on features formulated from spectral components of the image. Three image thresholding techniques were tested and evaluated on sample gold panning images. Color image thresholding in the CIELAB color space performed better in detecting and locating gold particles in an image. The proposed method will serve as a front-end technique for an automated gold panning system as it will automate the visual feature identification of gold particles and aid in the control of the handling system of the gold particles during the panning process.","PeriodicalId":442944,"journal":{"name":"2021 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128179390","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":"Design and Comparison of Three Surface-Mounted PM Motors for a Light Electric Vehicle","authors":"Francois du Plessis, Stavros Pastellides, Rong-Jie Wang","doi":"10.1109/SAUPEC/RobMech/PRASA52254.2021.9377239","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA52254.2021.9377239","url":null,"abstract":"Electric vehicles (EV) are increasingly used in both urban and industrial environments. Electric motors are the essential part of the EV power train systems. Different types of electric motor technologies have been developed for the purpose. Amongst others, permanent magnet synchronous motors (PMSM) are widely used for EV applications because of their unique advantages such as high efficiency and high power density. This paper presents the optimal design of three different surface-mounted PMSMs with fractional-slot toothconcentrated and distributed winding topologies, respectively. The performance comparison of these motors will outline their respective advantages and disadvantages.","PeriodicalId":442944,"journal":{"name":"2021 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131796414","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":"Why Solar PV is Such a Lucrative Option for South African Municipal Customers","authors":"S. Sewchurran, I. Davidson","doi":"10.1109/SAUPEC/RobMech/PRASA52254.2021.9377024","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA52254.2021.9377024","url":null,"abstract":"South Africa produced some of the cheapest electricity in the world pre-2008, until its experienced energy shortages leading to constant under frequency load shedding and above inflation tariff increases. There has since been major research and development in the field of renewable energy generation. With new rules and regulations in place to favor renewable energy with its short lead times, ensuring environmental sustainability and energy security in the country. Municipalities are starting to see a surge in the installation of Small-Scale Embedded Generation, more especially rooftop solar PV technology. This is an alarming factor to municipalities in South Africa as the potential for revenue loss remains a major threat on their existing business model. In order to better understand what is driving business and bulk energy use customers to install solar PV and why is solar PV such a lucrative option to municipal customers in South Africa, an investigation was carried out. The eThekwini Municipality was used for this investigation.","PeriodicalId":442944,"journal":{"name":"2021 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117296766","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":"Investigation and mitigation of temporary overvoltage caused by harmonic filters in an oil refinery","authors":"Prenushka Ayar, Olatunji Ajibola Akinrinde, E. Ojo","doi":"10.1109/SAUPEC/RobMech/PRASA52254.2021.9377227","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA52254.2021.9377227","url":null,"abstract":"Harmonic distortion caused by non-linear loads pose a threat to power quality that may result in failures or damage to various components of the electrical system. In this work the harmonic distortion in an oil refinery is investigated using the ATP/EMTP software. Harmonic filters are used to reduce harmonic distortion by diverting harmonic currents in low impedance paths. The switching activities of the harmonic filter may cause overvoltage to occur in the refinery causing adverse effects to the electrical system. This paper presents an investigation of the temporary overvoltage caused by the energizing and de-energizing of the filter with the aim to determine whether they exceed the withstand limits of the system. Thus, mitigation measures would be needed if the overvoltage is greater than the power frequency withstand level. For this reason, the use of pre-insertion resistors, surge arresters and controlled switching is considered to ascertain the effectiveness these components would have on mitigating the overvoltage.","PeriodicalId":442944,"journal":{"name":"2021 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116095521","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":"Anomaly Detection Monitoring System for Healthcare","authors":"Tlou Boloka, Gerrie Crafford, Windy Mokuwe, B. V. Eden","doi":"10.1109/SAUPEC/RobMech/PRASA52254.2021.9377017","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA52254.2021.9377017","url":null,"abstract":"Most developing countries suffer from inadequate health care facilities and a lack of medical practitioners as most of them emigrate to developed countries. The outbreak of the COVID-19 pandemic has left these countries more vulnerable to facing the worse outcome of the pandemic. This necessitates the need for a system that continuously monitors patient status and detects how their physiological variables will change over time. As a result, it will reduce the rate of mortality and mitigate the need for medical practitioners to monitor patients continuously. In this work, we show how an autoencoder and extreme gradient boosting can be merged to forecast physiological variables of a patient and detect anomalies and their level of divergence. An accurate detection of current and future anomalies will enable remedial action to be taken by medical practitioners at the right time and possibly save lives.","PeriodicalId":442944,"journal":{"name":"2021 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117258524","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":"Ferroresonance: A Review of the Phenomenon and Its Effects","authors":"S.J. Kruger, J. D. de Kock","doi":"10.1109/saupec/robmech/prasa52254.2021.9377238","DOIUrl":"https://doi.org/10.1109/saupec/robmech/prasa52254.2021.9377238","url":null,"abstract":"This paper aims to provide a review of the current literature on the topic of ferroresonance. The definition of ferroresonance and the requirements for transients to be classified as such are discussed and then the paper identifies the various factors which influence ferroresonance and its initiation. The four main modes of ferroresonance are identified, along with the criteria for their classification. Finally, the paper discusses the effects that ferroresonance can have on the power system. The paper does not discuss ferroresonance analysis or mitigation strategies.","PeriodicalId":442944,"journal":{"name":"2021 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121465190","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":"The economic and environmental impact of replacing geyser with air source heat pump water heater","authors":"S. Tangwe, K. Kusakana","doi":"10.1109/SAUPEC/RobMech/PRASA52254.2021.9377225","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA52254.2021.9377225","url":null,"abstract":"The study focused on the evaluation of the energy cost saving and greenhouse gas emission reduction when a 3.0 kW electric geyser is replaced by a 1.2 kW split type ASHP water heater. Both hot water devices were of 150 L capacity and are set up to operate simultaneously under specific volumes of hot water drawn off (150, 50 and 100 L) in the morning, afternoon and evening each day over a year. The data acquisition system comprising of flow meters, temperature sensors, power meters, ambient temperature and relative humidity sensor and a data logger. The data acquisition system was built and installed to monitor the performance of the hot water devices. The results depicted that the average monthly energy saving and CO2 reduction achieve with the ASHP system due to the 300 L of daily volume of hot water drawn off was 203.67 kWh and 201.63 kg, respectively for the summer season. The average monthly cost saving for the summer period based on the flat rate tariff (FR) and the time of use (TOU) tariff was R25S.66 and R 296.35. In addition, the average monthly energy and CO2 impact of the ASHP water heater due to the daily 300 L of hot water drawn off was 249.24 kWh and 246.74 kg, respectively for the winter season. The corresponding average monthly flat rate and time of use cost saving for the winter season was R 378.84 and R 719.26. The average month-day COP for both the summer and winter seasons was 2.90 and 2.49, respectively. A firm conclusion can be established that the time of use cost saving is higher than the flat rate cost saving due to the relatively higher electricity tariff structure attributed to the time of use electricity plan especially during the peak periods. Despite, the low average month-day COP experienced by the ASHP water heater in the winter as opposed to the COP for the average month-day in the summer period, the electrical energy saving of the ASHP water heater was higher due to the lowered makeup water temperature. These lowered makeup water temperature is associated with a greater electrical energy consumed and thermal energy gained before hot water set point temperature is attained after the hot water drawers.","PeriodicalId":442944,"journal":{"name":"2021 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"54 17","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113957361","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":"Discriminating Between Magnetizing Inrush Current and Fault Current in Power Transformer Protection using Wavelet Transform","authors":"Franklin Eguavoen Obakpolor, A. Saha","doi":"10.1109/SAUPEC/RobMech/PRASA52254.2021.9377217","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA52254.2021.9377217","url":null,"abstract":"This paper presents the discrimination between magnetic inrush current and fault current for power transformer protection using wavelet transform. The wavelet transform which can simultaneously collect information from transient signals in both frequency and time domain is employed in the analysis of power transformer transient phenomena in several conditions of inrush and internal fault currents. The fault conditions regarding the power transformer were modeled in MATLAB/SIMULINK environment and the discrete waveform transform was applied to decompose the fault signals up to level 5 into several detailed wavelet components. The test results from the simulations showed that the deeper the level of decomposition the better the attainment of obtaining good distinguishing characteristics as levels 1 and 5 of the waveforms presented in this work proved this concept.","PeriodicalId":442944,"journal":{"name":"2021 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132672424","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":"Smart Inverters in LV networks: A Review of International Codes and Standards, and Opportunities for South Africa","authors":"R. Xavier, B. Bekker, M. J. Chihota","doi":"10.1109/SAUPEC/RobMech/PRASA52254.2021.9377224","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA52254.2021.9377224","url":null,"abstract":"Over the past few decades, the percentage of grid-interconnected distributed energy resources (DERs) has increased significantly. Even higher percentages are expected in the future as more countries implement policies, energy resource plans, and incentives towards the adoption of renewable energy. However, it is not so simple to progress towards a larger penetration of DERs, as there are associated technical challenges that threaten the existing distribution network’s stability, reliability, and power quality. Smart inverters can be used to address grid integration issues related to voltage or frequency, disconnection from the grid, and overgeneration, through dynamic and central operation and control of these inverters. Due to the grid support provided by smart inverters, various countries have redefined grid codes motivated by the need to optimize distributed generation (DG) utilization while ensuring system adequacy. This paper explores existing grid codes and related regulations within the context of advanced inverter functionality, in leading states and countries with high DG penetration, particularly Germany, California, and Hawaii. The content of the international regulations are contrasted with those in South Africa to identify areas where changes are needed. The results show that South Africa would benefit from having a communication protocol, similar to IEEE 2030.5, as well as defined voltage and frequency regulation functions, similar to those stated in California Rule21 and Hawaii Rulel4H. Standards modification to include smart inverter requirements that are applicable for all DER sizes and types, including solar, wind, energy storage, and smart loads, would also be beneficial.","PeriodicalId":442944,"journal":{"name":"2021 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127793957","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":"Scenario-Based Analysis of the Adequacy of a South African Grid to Supply Peak Demand in 2030","authors":"Siyanda Ncwane, Thamsanqa Ngcobo","doi":"10.1109/SAUPEC/RobMech/PRASA52254.2021.9377249","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA52254.2021.9377249","url":null,"abstract":"The transmission development plan (TDP) is updated annually in South Africa. The TDP identifies projects to strengthen the network to supply future load demand and integrate new power generation plants. The TDP of the grid investigated is planned with all the generation units in each of the power stations supplying the grid in service. However, outages can occur on the power station units, resulting in the grid being inadequate to supply the peak network load demand during this period. The paper demonstrates the scenarioplanning approach in investigating the adequacy of a power transmission grid with multiple generation injection points to meet peak load demand under multiple generation scenarios. The investigation is performed on the 2030 network of a power transmission grid in South Africa. It is found that even though the TDP of the power transmission grid is planned with all the generation units of the power stations supplying the grid in service, there is adequate network capacity in the year 2030 to supply the peak load demand when multiple generation scenarios are investigated. Also, the benefits of analysing multiple generation scenarios to ensure that the power transmission grid has enough capacity to supply the peak load demand in a given time interval of study are highlighted.","PeriodicalId":442944,"journal":{"name":"2021 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134257745","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}