Browsing Faculty of Engineering by Author "Van Schoor, G."
Now showing items 1-20 of 25
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Characterisation of a PEM electrolyser using the current interrupt method
Martinson, C.A.; Van Schoor, G.; Uren, K.R.; Bessarabov, D. (Elsevier, 2014)A method is proposed to model the electrochemical characteristics of a Proton Exchange Membrane (PEM) electrolyser. The electrochemical characteristics, which include the Ohmic, activation and concentration losses, are ... -
A current analysis and correction system for vibration forces on the rotor of a rotating active magnetic bearing system
Gouws, R.; Van Schoor, G. (SAIEE, 2007)In this paper, an on-line detection, correction and identification system for vibration forces on the rotor of a rotating active magnetic bearing is proposed. The on-line detection system performs current analysis by ... -
The development process of an axial active magnetic bearing
Gouws, R.; Van Schoor, G. (2005)The purpose of this paper is to motivate and inspire students to investigate and understand fundamental principles of electrical engineering such as magnetic levitation, control theory and sensor design. This paper describes ... -
Energy-based visualisation of an axial-flow compressor system for the purposes of fault detection and diagnosis
Fouché, L.B.; Uren, K.R.; Van Schoor, G. (Elsevier, 2016)As the complexity of industrial systems increases, the necessity also increases for more reliable, robust and accurate Fault Detection and Diagnosis (FDD) techniques. This article proposes a methodology for the design of ... -
Enthalpy-entropy graph approach for the classification of faults in the main power system of a closed Brayton cycle HTGR
Du Rand, C.P.; Van Schoor, G.; Nieuwoudt, C. (Elsevier, 2009)An enthalpy–entropy (h–s) graph approach for the classification of faults in a new generation type high temperature gas-cooled reactor (HTGR) is presented. The study is performed on a 165 MW model of the main power system ... -
Evaluation of demodulation algorithms for robust self-sensing active magnetic bearings
Van Schoor, G.; Niemann, A.C.; Du Rand, C.P. (Elsevier, 2013)Active magnetic bearings (AMBs) play a key role in various industrial applications. In the ongoing challenge to reduce the number of external sensing devices and manufacturing costs of AMBs, self-sensing techniques have ... -
Fault diagnosis of generation IV nuclear HTGR components. Part 1. The error enthalpy-entropy graph approach
Du Rand, C.P.; Van Schoor, G. (Elsevier, 2012)Fault diagnosis (FD) is an important element in modern nuclear power plant (NPP) diagnostic systems. In this respect, FD of generation II and III water-cooled nuclear energy systems has become an active research topic to ... -
Fault diagnosis of generation IV nuclear HTGR components. Part 2. The area error enthalpy-entropy graph approach
Du Rand, C.P.; Van Schoor, G. (Elsevier, 2012)The second paper in a two part series presents the area error method for generation of representative enthalpy–entropy (h–s) fault signatures to classify malfunctions in generation IV nuclear high temperature gas-cooled ... -
Frequency dependent impedance model for heteropolar magnetic bearings
Ranft, E.O.; Van Schoor, G.; Du Rand, C.P. (Elsevier, 2015)Accurate analytical models are fundamental to design and optimise high performance magnetic bearings. Understanding the bearing’s dynamic behaviour over its operational envelope is essential to this task and is performed ... -
Fuzzy logic controller with neurol network signal predictors for complex split-range control of a hybrid actuator
Van Schoor, G.; Breed, D.G.; Du Rand, C.P. (Elsevier, 2013)This paper presents an integrated fuzzy logic controller (FLC) to address challenges associated with complex split-range control of a two-valves-in-parallel hybrid actuator. Split-range hybrid valve (HV) control aims to ... -
Genetic algorithm based PID tuning for optimal power control of a three-shaft Brayton cycle based power conversion unit
Uren, K.R.; Van Schoor, G. (Elsevier, 2012)This paper considers the development of a PID control strategy to optimally control the power output of a High Temperature Gas-cooled Reactor (HTGR) power plant. A specific type of HTGR called the Pebble Bed Modular Reactor ... -
Genetic fuzzy rule extraction for optimised sizing and control of hybrid renewable energy hydrogen systems
Human, G.; Van Schoor, G.; Uren, K.R. (Elsevier, 2020)A major challenge related to the design of a hybrid renewable energy hydrogen system is which energy sources to include and at what capacity, for regionally different potentials of renewable energy and hydrogen demand. In ... -
Hydrocyclone cut-size estimation using artificial neural networks
Van Loggenberg, S.; Van Schoor, G.; Uren, K.R.; Van der Merwe, A.F. (Elsevier, 2016)The hydrocyclone is widely used throughout the mineral processing industry when working with slurries. It is either used for classifying, desliming or dewatering. Hydrocyclones are inexpensive, application-efficient and ... -
Improving dynamic microgrid modelling through the use of synchronised field data
Erasmus, R.J.; Rens, A.P.J.; Van Schoor, G.; Uren, K.R. (IEEE, 2020)Simulation during the design and operation of microgrids should include dynamic phenomena that would be a result of the unpredictable variation in renewable generation and loading. Detailed modelling of different components ... -
Integrated procedure for vibration characterization of a magnetic bearing supported rotor delevitation system
Bean, J.; Van Schoor, G.; Du Rand, C.P. (Elsevier, 2016)This paper considers an integrated procedure to verify and validate (V&V) the rotordynamic analyses of a magnetic bearing supported rotor delevitation system (RDS). Rotor-AMB (active magnetic bearing) systems in general ... -
An integrated self-sensing approach for active magnetic bearings
Ranft, E.O.; Van Schoor, G.; Du Rand, C.P. (IEEE, 2011)Self-sensing permits active magnetic bearings (AMBs) to consolidate the actuation and sensing functions into a single electromagnetic transducer. Eliminating the position sensing device as well as interfacing reduce potential ... -
Microgrid energy management through levelized cost of energy metric
Swanepoel, C.G.; Van Schoor, G.; Uren, K.R.; Rens, A.P.J. (IEEE, 2020)The abundance of solar energy in Africa provides the ideal opportunity to mitigate the concerns on price, reliability and voltage quality of electricity supply to end-users. Rooftop PV and local energy storage solutions ... -
Model predictive control of an active magnetic bearing suspended flywheel energy
Uren, K.R.; Van Schoor, G.; Aucamp, C.D. (SAIEE, 2015)Flywheel Energy Storage (FES) is rapidly becoming an attractive enabling technology in power systems requiring energy storage. This is mainly due to the rapid advances made in Active Magnetic Bearing (AMB) technology. ... -
Multivariable H∞ control for an active magnetic bearing flywheel system
Steyn, S.J.M.; Van Vuuren, P.A.; Van Schoor, G. (IET, 2010)A state-space model with uncertainties for an active magnetic bearing energy storage flywheel system (Fly-UPS) is developed. A multivariable robust H∞ controller for the Fly-UPS is then synthesised. Different weighting ... -
Non-linear model of rotor delevitation in an active magnetic bearing system including parameter estimation
Janse van Rensburg, J.J.; Van Schoor, G.; Van Vuuren, P.A.; Janse van Rensburg, A. (Elsevier, 2017)Backup bearings (BBs) are used to protect active magnetic bearings in the event of rotor delevitation. To gain insight into the design, selection and operation of BBs, a model that can accurately simulate the behaviour of ...