The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
It is a setback that many projects face and senior management fear, that a well-run project heading for success can take a turn for the worst when the project manager is replaced as a result of resignation or transfer. The replacement of the leader and foundation of the project can result in poor management of the triple constraint (scope, time and budget), loss of historical project information,...
The Engineering Management degree at master's level has been taught at a South African higher education institution for more than 20 years. The student enrollment numbers have seen significant growth over the last decade, with a year-on-year growth varying from 20% to 39% each year. The coursework master's program consists of a number of lectured modules and a research component which accounts for...
The savings calculation methodology from a fan replacement project is presented in this paper. The fans replaced are part of the underground ventilation system in a platinum mine. Initially, 290 axial flow fans rated at 45kW were to be replaced with carbon fibre composite fans. According to the manufacturer, the carbon fibre construction allowed for an optimum blade shape which results in the carbon...
South Africa's increasing cost of industrial energy has recently caused the country to be ranked among the top five countries in the world with the most expensive industrial electricity tariffs. For various reasons, energy is often not optimally used in industry. According to Zavanella and Zanoni (2009), there has been a growing interest in more rational and responsible consumption of energy, especially...
Transformers which are not designed to operate under harmonic loading will experience higher than usual temperature increases in the windings due to the added harmonic current. This paper uses the IEEE 519 and NRS 048-2 power quality standards which define harmonic limits of voltage THD (Total Harmonic Distortion) and IHD (Individual Harmonic Distortion) and the IEEE C57.110 standard which uses the...
Energy Conservation projects have become a focus area throughout the world in an attempt to reduce greenhouse gasses. These projects encompass various energy efficient technologies of which the retrofit of old technologies with new technology has become a common phenomenon. Energy savings are usually quantified by comparing actual post-retrofit energy consumption levels with baseline levels representative...
The research in this paper measured the Cultural Intelligence capability of engineering project leaders and team members from around the world, and their awareness of cultural influences on project management. The focus was on comparing South African engineers to those in other countries. It was concluded that intercultural communication and differences in decision-making were two primary cultural...
Prototyping of subsystem and system components is most often thought of as a development task. This paper shows the usefulness of prototyping as an activity in the requirements elicitation process, prior to any development activities. It is approached from the field of engineering and technology management. It uses the Requirements Engineering approach to identify tools and methods for the development...
The requirements engineering process is typically executed, irrespective of the process model chosen, for the final commercially viable system. The system requirements generated are for a system deployed and used in its final form and function. However, the first prototype that is generated is typically representative of a minimum viable technology, and represents a degraded set of the initial system...
This paper is an extension and elaboration of previous research on the simulation of three competing technologies that interact. A modified version of the three-technology system is investigated, and some initial system dynamics results are reported illustrating the progression from asymptotic to cyclic behaviour. Technology is considered in this research as a result of innovation, a rate-dependent...
Voltage regulation is one of the critical quality of supply aspects in any power system. Due to this requirement, voltages must almost always be kept within the utilities defined lower and higher limits. Loads that vary substantially between peak and off-peak times can results in voltages exceeding the upper limits when the load is low and exceeding the lower limits when the load is high. Due to these...
Published research findings [1,2] on the effect of tap changer position of transformer on the steady state and voltage stability performance of a network with very high voltage transmission lines operating in parallel with a well developed corridor of 400kV lines showed that the tap changer position of a 765/400kV transformer has a significant effect on the power flow, active power losses, and voltage...
This paper is an extension of previous research on the simulation of three competing technologies that interact. Some exploration into cyclic behaviour of a modified version of the three technology system is attempted. Technology is considered in this research as a result of innovation, a rate dependent process that may include several non-linearities due to interaction with the environment. Technology...
The Upington distribution network is remotely located from the main transmission system. It is characterized by long lines supplying relatively small amounts of loads. The fault levels at various points in this network can be characterized as very low. These two aspects can lead to this network being characterized as very weak. As a result, faults taking place at various locations in the system tend...
Various assessment methods are used for analyzing voltage regulation data when reporting electrical transmission system performance. There is an international debate as to which of these assessment methods are the best. A statistical analysis of measured voltage regulation data for the Eskom transmission network was undertaken to investigate the implication of using the various assessment methods...
High Voltage Direct Current (HVDC) offer better capability for long distance, bulk power transmission compared to ac lines. Among the reasons for this is that HVDC does not suffer from stability limitations that ac lines experience. Also, the power that is required to be sent via HVDC lines can be scheduled as desired, whereas the power flowing through ac lines is directly influenced by the topology...
The lines that supply customers are usually of radial topology, and their backbones are built at medium voltages (usually 11kV and 22kV). The loading of the main backbones of such lines are influenced by the total size, in MVA, of the customers connected to the lines. These lines generally are not connected to other lines. Sometimes, interconnectors between such lines are created so that if one line...
The Upington area within South Africa is well-endowed with solar resources, with relatively high annual solar radiation recorded compared to other parts of the country. The distribution network in the area comprises very long lines, has very low fault levels, and is very prone to voltage dips. Previous studies [1] have investigated the feasibility and network considerations of connecting concentrating...
Previously published research findings [1] on the impact of tap changer position on the steady state performance of distribution networks indicate that very little impact results from varying the tap changer position. In this paper, a similar investigation is carried out, but on a network with very high voltage transmission lines operating in parallel with a well-developed corridor of 400kV lines...
At present, Eskom is investigating the feasibility of connecting a concentrating solar power (CSP) plant in the distribution network located in Upington. This is informed by the Integrated Strategy Energy Plan (ISEP) which is a corporate plan for future energy needs, including the type of fuels to be used and the timing of the commissioning of various plans. The CSP plant under investigation will...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.