2019 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)最新文献
Chaniel Precious Allessing, J. Van Coller, H. Kruger
{"title":"Simulation-based analysis of the anti-islanding requirement specified within the Grid Connection Code for Renewable Power Plant (GCCRPP)","authors":"Chaniel Precious Allessing, J. Van Coller, H. Kruger","doi":"10.1109/ROBOMECH.2019.8704752","DOIUrl":"https://doi.org/10.1109/ROBOMECH.2019.8704752","url":null,"abstract":"Coupling Renewable Power Plants (RPPs) into the grid introduces a new concept to the operation of the network: that of islanding. Islanding is when the link to the utility network becomes disconnected, but the RPP continues to supply the load (islanded load matches RPP generation). The presence of Distribution Generation (DG) in networks usually results in islanding not being allowed, this is because the utility does not have control and/or visibility over its plant in the islanded portion of the network as well as the power quality the customer will experience. Islanding also poses a risk to utility workers and equipment. The South African Grid Connection Code for Renewable Power Plant (GCCRPP) connected to the transmission and distribution system [1] stipulates that islanding must be detected and terminated within a maximum time of two seconds. This research investigates what the parameters are that determine what the maximum time should be. Preliminary studies have been conducted for synchronous DG which suggests that amendments could be possible for the GCCRPP to detect and terminate the islanding condition within a time less than the presently specified two seconds. Further research should be conducted to include inverter based-DG and different types of islanding detection methods for amendment to be concluded.","PeriodicalId":344332,"journal":{"name":"2019 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"137 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131984628","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":"Application of static var compensator with harmonic filters in the heavy industry","authors":"Nkululeko Motlanthe, L. Muremi","doi":"10.1109/ROBOMECH.2019.8704729","DOIUrl":"https://doi.org/10.1109/ROBOMECH.2019.8704729","url":null,"abstract":"Utility companies use Flexible AC Transmission Systems (FACTS) to improve the power quality at load end closer to furnaces, steel plants and mining facilities in order to avoid the generating of reactive power through field excitation of generator as this reduces the efficiency of the power grid network. In this paper the focus is on application of static var compensator (SVC) with shunt filters on Waterval chrome mine network in order to improve the voltage level and reduce the total harmonic content within internal point of common coupling (IPCC) where nonlinear loads are connected. Power quality scans were performed with reference to the NRS 048 regulations. The network was modeled and analysed using the DIgSILENT Power Factory 2018 and a comparison was done using both results. The investigation provided evidence of compliant in terms of voltage harmonics and voltage compatibility levels at common point of coupling (PCC). Reactive power over compensation was noted due to nonadaptive absolute fixed capacitor banks. The results were coherent with the simulated mine network, but a significant voltage drops downstream at IPCC where nonlinear loads are connected caused deviation in harmonics with reference to IEEE 519 standard. In addition, it was discovered that the more rectifier nonlinear devices connected to a load bus, the more the voltage total harmonic distortion in which mitigation was implemented using shunt filters. The significant voltage drop that was noted from the simulated network downstream was improved using static var system.","PeriodicalId":344332,"journal":{"name":"2019 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133471429","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":"Operating Induction Machine in DFIG Mode Including Rotor Asymmetry","authors":"A. Salah, D. Dorrell","doi":"10.1109/ROBOMECH.2019.8704826","DOIUrl":"https://doi.org/10.1109/ROBOMECH.2019.8704826","url":null,"abstract":"This paper develops a model for accurately analysing the behaviour of a wound rotor induction machine, which are often used as doubly-fed induction generators, with rotor faults. Variations in the amplitude of stator current components are used to detect these faults, including electrical asymmetry of the external-connected rotor resistances of a four-pole wound rotor. The steady state performance was investigated by means of an equivalent circuit which includes the rotor asymmetries. It is tested successfully on a three-phase balanced and unbalanced induction machine.","PeriodicalId":344332,"journal":{"name":"2019 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":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116541288","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 Effect of a Phase Shift Transformer For Power Flow Control","authors":"M. Thwala, A. Nnachi, K. Moloi, A. Akumu","doi":"10.1109/ROBOMECH.2019.8704776","DOIUrl":"https://doi.org/10.1109/ROBOMECH.2019.8704776","url":null,"abstract":"Power systems have undergone major transformations in recent times which have a brought dynamic change in the manner which transmission system is operated. This transformation can be attributed to factors such as population growth and industrialization, amongst others. What has been classified as the major issue of this transformation is power flow control in the interconnected systems. It is for this and other reasons that developed countries are installing and using power flow control devices in their power systems at an alarming rate. In this paper, the effect of using a phase shift transformer (PST) is demonstrated for power flow control.","PeriodicalId":344332,"journal":{"name":"2019 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124896254","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}
T. Mokgonyane, T. Sefara, T. Modipa, Mercy Mosibudi Mogale, M. J. Manamela, P. J. Manamela
{"title":"Automatic Speaker Recognition System based on Machine Learning Algorithms","authors":"T. Mokgonyane, T. Sefara, T. Modipa, Mercy Mosibudi Mogale, M. J. Manamela, P. J. Manamela","doi":"10.1109/ROBOMECH.2019.8704837","DOIUrl":"https://doi.org/10.1109/ROBOMECH.2019.8704837","url":null,"abstract":"Speaker recognition is a technique used to automatically recognize a speaker from a recording of their voice or speech utterance. Speaker recognition technology has improved over recent years and has become inexpensive and and reliable method for person identification and verification. Research in the field of speaker recognition has now spanned over five decades and has shown fruitful results, however there is not much work done with regards to South African indigenous languages. This paper presents the development of an automatic speaker recognition system that incorporates classification and recognition of Sepedi home language speakers. Four classifier models, namely, Support Vector Machines, K-Nearest Neighbors, Multilayer Perceptrons (MLP) and Random Forest (RF), are trained using WEKA data mining tool. Auto-WEKA is applied to determine the best classifier model together with its best hyper-parameters. The performance of each model is evaluated in WEKA using 10-fold cross validation. MLP and RF yielded good accuracy surpassing the state-of-the-art with an accuracy of 97% and 99.9% respectively, the RF model is then implemented on a graphical user interface for development testing.","PeriodicalId":344332,"journal":{"name":"2019 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126011692","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":"Management of Grid-Connected Micro-grid Using Game Theory Approach","authors":"I. O. Oladejo, K. Folly","doi":"10.1109/SAUPEC/RobMech/PRASA46261.2019.9116579","DOIUrl":"https://doi.org/10.1109/SAUPEC/RobMech/PRASA46261.2019.9116579","url":null,"abstract":"A micro-grid consists of distributed energy resources (such as solar PV, Wind turbine, and fuel cell), interconnected load and storage sources. For the micro-grid to achieve better economic outcomes, the connected homes need to cooperate in order to obtain mutual benefit. Therefore, a method based on cooperative game theory, the generalized Nash bargaining solution is proposed. The novelty of the proposed method lies in the new profit distribution to favour certain participant by specifying different values of the negotiation power in the objective function. To demonstrate the effectiveness of the proposed work, a case study of 6 sites (buildings of different types, which may be shops, dwelling places and schools with their micro-sources results in micro-grid) is presented. A solution approach based on Teaching-Learning-based Optimization (TLBO) is proposed to achieve optimal results. To validate the feasibility of the method, the results obtained TLBO were compared with genetic algorithm (GA), which shows that the TLBO method is robust and capable of giving quality solution efficiently in solving energy management problem.","PeriodicalId":344332,"journal":{"name":"2019 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130310541","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":"Optimising the Design of a Hybrid Power Supply Using a Genetic Algorithm","authors":"F. Daniel, A. Rix","doi":"10.1109/ROBOMECH.2019.8704763","DOIUrl":"https://doi.org/10.1109/ROBOMECH.2019.8704763","url":null,"abstract":"This paper proposes the optimisation of a hybrid power supply (HPS) design by implementing a Genetic Algorithm (GA). Single-source renewable energy systems (RES) are associated with low capacity factor, high capital costs and intermittency. Combining two or more power sources, whether renewable or non-renewable, increases the system’s reliability in terms of power consistency, reduces fuel emissions and is a more sustainable and financial viable solution overall. A grid-connection and a battery storage system can further increase the dispatchability of the system. The design of each HPS can become more complex due to the location and stochastic availability of renewable energy sources. A GA is developed to solve this sizing problem. The objectives of the algorithm are: minimizing the loss of power supply probability, maximizing usage of renewable energy and minimizing capital and life cycle costs. A GA is developed to incorporate operational and dispatch strategies and a techno-economic and trade-off analysis is done to study the advantages and disadvantages of different combinations. This can help develop a methodology to choose the most suited HPS for the location and resource availability. The in-house GA will be compared with HOMER design software to highlight the similarities and differences between the two design strategies.","PeriodicalId":344332,"journal":{"name":"2019 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127699435","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":"Image Stitching for Usage in Photogrammetric Algorithms","authors":"Gene Stoltz","doi":"10.1109/ROBOMECH.2019.8704814","DOIUrl":"https://doi.org/10.1109/ROBOMECH.2019.8704814","url":null,"abstract":"A distributed camera system can consist of multiple camera groups. An image stitch is created by each group and transmitted to a central processing unit. The central processing combines all received images into an image stitch. The camera groups can have cameras with large overlapping areas and transmitting a stitched image will reduce the required bandwidth. Unfortunately, photogrammetric algorithms such as stitching, assume images adhere to the pinhole camera model. Thus, photogrammetric algorithms cannot be applied to image stitches created by currently available grid generation techniques.In this paper a grid generation method to create a stitched image with the properties of a pinhole camera is presented.The method is evaluated by simulating eight cameras, forming two groups, each group covering a quarter-hemisphere. The intrinsic and extrinsic parameters of each camera is known. A groundtruth is created by a spherical stitch of all eight cameras covering the half-hemisphere.To test, each camera group is stitched using the pinhole camera transformation. The transformation produce artificial intrinsic and extrinsic parameters for each stitch. A half-hemisphere spherical stitch is created using the two camera group stitches, each with their relative intrinsic and extrinsic parameters.The half-hemisphere stitch is compared to the groundtruth, producing almost perfect correlation. The high correlation indicates the success of the pinhole camera transformation. The pinhole camera transformation enable the usage of stitched images in photogrammetric algorithms.","PeriodicalId":344332,"journal":{"name":"2019 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":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126331546","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":"Development of In-Phase Bus Transfer Scheme Using Matlab Simulink","authors":"V. Mathebula, A. Saha","doi":"10.1109/ROBOMECH.2019.8704815","DOIUrl":"https://doi.org/10.1109/ROBOMECH.2019.8704815","url":null,"abstract":"Main-tie-main reticulation configuration is used to improve reliability of power supply in power plant unit auxiliary systems due to its redundant characteristic. Two main supplies are used to supply power to two sets of loads respectively, while both supplies serve as back-up supplies to each other in the event that one of the supplies is lost as a result of upstream equipment failure. Combination of various boiler auxiliary loads such as pumps, fans and mill, coupled with slow circuit breaker operating times makes it difficult to guarantee fast bus transfer execution when main power supply is lost. The paper focusses on the design of in-phase bus transfer scheme, which is relatively faster than residual voltage bus transfer scheme; and therefore making it the most preferred back-up transfer scheme to fast bus transfer. The paper also investigates its characteristic and impact on the electrical system as well as the driven load insofar as the transient accelerating current and torque is concerned using Matlab Simulink. The results indicate that in-phase bus transfer process is relatively smooth for the motor and the driven load.","PeriodicalId":344332,"journal":{"name":"2019 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"940 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120931235","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 Strategy of Traction Induction Motors","authors":"T. Masuku, R.-J. Wang, M. Botha, S. Gerber","doi":"10.1109/ROBOMECH.2019.8704761","DOIUrl":"https://doi.org/10.1109/ROBOMECH.2019.8704761","url":null,"abstract":"In this paper, a strategy for designing induction motors for traction applications is proposed. The proposed strategy builds on the conventional design of induction motors, but makes emphasis on the differentiating characteristics, which are the constant power speed ratio and overloading capability. A design procedure, which breaks up the motor design into different parts and phases was formulated. The formulated design strategy was then validated by the design of a 3kW traction induction motor using the ANSYS Electronics packages. ANSYS RMxprt was used in conjunction with ANSYS Optimetrics optimization module to create an initial optimum design, which was then verified by using ANSYS Maxwell 2D finite element analysis. The proposed design strategy has been shown to work well.","PeriodicalId":344332,"journal":{"name":"2019 Southern African Universities Power Engineering Conference/Robotics and Mechatronics/Pattern Recognition Association of South Africa (SAUPEC/RobMech/PRASA)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131085793","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}