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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Die ekonometriese modellering van elektrisiteitsverkope deur Eskom in die Johannesburg en Pretoria gebiede

21 May 2014 (has links)
M.Com. (Econometrics) / An attempt has been made in this study to model electricity sales of Eskom with the aid of an econometric model. The study examines the history of econometric modeling and the applications thereof. These applications include forecasting, policy simulation and policy analysis. The sales of electricity within the specific sales categories is estimated and simulated with the use of an econometric model. The model is specified according to the expected dependent and explanatory variables. The a priori theoretical considerations concerning the size and sign of the parameters of the function are also included in the specification, as well as the mathematical form of the model. The specification process of the econometric model is based on econometric theory and on available information relating to the phenomenon being studied. The method of ordinary least squares is used in the estimation of the parameters of the model. As this is an econometric study, the emphasis is on the evaluation of the results. Economic a priori criteria, statistical criteria and econometric criteria are used to evaluate the results of the parameters obtained by the method of ordinary least squares. Several tests, including the Goldfeld Quandt test for heteroscedasticity, the Durbin-Watson test for auto correlation and the Frisch analysis of multicollinearity are executed. The overall results of the tests to which the model was subjected, was satisfactory. The best functions are combined in a structured model. This model is simulated with the use of the Gauss-Seidel-method and forecasts of historical values are obtained. Statistical tests for the validation of these results, as well as Theil's inequality coefficient are applied to test the forecasting power of the model. The results of the ex post forecast for the period 1988.1 to 1995.1 emphasize the usefulness of the model as a forecasting device and the dynamic simulation demonstrates the ability of the model to reproduce the historical data from which it is estimated.
22

Investigation into current transformer failures within Eskom distribution.

Rampersad, Deepak. January 2010 (has links)
Conventional Current Transformers (CTs) provide the input signal required by protection relays, control equipment and energy metering in power networks. Catastrophic failures of CTs may lead to injury of personnel within the substation, interruption of power supply and damage to adjacent high voltage equipment. One of the causes of CT failures is high values of insulation power factor. Research indicates that with increasing primary insulation power factor values, partial discharges develop between the paper insulation leading to its exponential decay with the end result of an ultimate CT failure. Reports in Eskom Distribution indicated that a number of CTs from one manufacturer were exceeding the specified insulation power factor value. This research was initiated to investigate the impact of high power factor on the premature failure of CTs. This study serves to analyse the significance of power factor on paper-oil insulation within a hair-pin type CT. The internal primary insulation of a hair-pin type CT used in Eskom Distribution is reviewed in terms of its design, construction and relevant tests. Sample CTs rated at 132kV and manufactured in the year 2007 to 2009 from the specific manufacturer were selected for insulation power factor testing. The Doble M4100 diagnostic test system was used to perform the testing that also assisted in providing a comparison between the units with high insulation power factor values and that which were within the specified limits. The results show that the high values of insulation power factor give a direct indication of the dielectric losses (I2R) within that CT, which inadvertently indicates the shortened serviceable life of that CT. High moisture content within the primary insulation, low quality insulating oil and inadequate quality assurance were identified as some of the contributory factors in the CTs non compliance. The effects of high values of insulation power factor are the primary factor for continuous on-line condition monitoring techniques that enable data trending and provide for early warning of an imminent CT failure. The testing of the sample CTs provided a more dynamic approach for recommendations to prevent the installation of such units into the power network. / Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2010.
23

Impact of series compensation on the perfomance of distance protection on Eskom transmission grid.

Qwabe, Sihle. January 2010 (has links)
Modern transmission systems are becoming heavily loaded. In addressing this issue Eskom has been installing series capacitors in their power transmission grids for the purposes of ensuring improved system stability, increased transmittable power, reduced transmission losses, enhanced voltage control and more flexible power flow control. Environmental concerns are also addressed at a fraction of the cost when compared to the alternative. However, with the utilization of series capacitors and their over-voltage protection devices typically the Metal Oxide Varistors and Spark Gaps when installed on transmission lines, several problems are created for the distance protection relays. This is because series capacitors when used on transmission lines can have serious effects on the performance of distance relay protection. This is because of the change of impedance seen by the distance relay since the electrical impedance measured by the relay is no longer a unique correspondence of the physical distance from the relay location to the point of fault when the protection of the series capacitors comes into play. The research results will show that, because of subsynchronous oscillations and voltage inversion phenomena as a result of series compensation, can cause distance protection’s zone 1 directional elements to operate incorrectly, more specific to internal faults which may appear as external faults and external faults which may appear as internal faults. The research will be investigating some of the challenges that are encountered by the distance protection relays when protecting a transmission line incorporating series capacitors. In answering the research question: “What are the issues associated with the utilization of series capacitors on the Eskom Transmission grid to the performance of distance protection?” the Digsilent PowerFactory software simulator package will be utilized to achieve the desired objectives. Other research projects have looked into the research question at hand utilizing the physical REL 531 relays and a real time model of the Eskom Hydra South Network, a system that supplies power to the Western Cape. In this research the author will be looking at the ability of Digsilent and its REL 531 Models to repeat and confirm the same conclusions, before considering possible alternative solutions. The Muldersvlei-Bacchus and Bacchus-Droerivier lines forming part of the Eskom Hydra South Network were selected as the area of focus. The decision to select these two particular mentioned lines as the area of focus was because the studies will be able to cover impact of external series capacitors to both the performance of the relays on lines that are series compensated and those that are not. The performance of the relays will involve analyzing the impact of series capacitors on the relays for faults before and after series capacitors. The research will also be investigating the possibility of utilizing the current supervised zone 1 configuration, which has recently been introduced on some Eskom distance protection relays as a solution, to overcome the impact of series capacitors on the performance of the distance protection relays. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2010.
24

Investigation into training strategy for graduate engineers in the capital expansion department of Eskom Enterprises Division [electronic resource]

Sithole, Sabelo Emmanuel. 22 August 2013 (has links)
Chapter 1 will cover the general background on training outside and inside Eskom. It will scrutinise the existing training programme taking into account the factors that inform this training. An assessment will also be made of the training strategy that the CED is already using. Chapter 2 will present an in-depth literature review that will serve as a guide in scrutinising training and development of the organisation and the staff. The literature in question covers coaching, mentoring, staff development, communication as a factor of training, induction, orientation, skills sharing, training evaluation, training objectives, job rotation, and skills knowledge. This literature will allow me to compare training in Eskom with that which is suggested from the literature review. This will be done in order to recommend solutions for training strategy problems in the CED. Studies touching on training have been undertaken in the past and this dissertation will also make use of them as references. Chapter 3 describes the research methodology used and the method of data collection. The three groups of staff that have been used to obtain data in the CED Camden Power Station, namely, discipline engineering managers, senior engineers and graduates in training, are also discussed. Chapter 4 presents the data analysis. All the data obtained from questionnaires and literature is analysed here. The analysis makes use of pie charts to analyse the data obtained from the respondents. Chapter 5 covers recommendations and conclusions. Recommendations are made based on responses to the research questionnaires. Research questionnaires that were used to obtain data are in the appendices. / Thesis (M.Com.)-University of KwaZulu-Natal, Westville, 2009.
25

Employee perceptions of energy management programmes at Eskom New Germany.

Rajpal, Leena. 05 June 2014 (has links)
Over the years, harmful impacts on the environment have led to a growing awareness of managing the environment. This trend to protect the environment has grown both locally and internationally. The increased pressure from the public, private and government structures have resulted in companies taking more responsibility for the environment. One of the major environmental areas is the management of energy. The poor planning by the South African government has resulted in serious shortage of energy (electricity) to consumers. In 2008 and 2009, Eskom could not meet the demands for electricity, resulting in load shedding across South Africa. The short-term solution was to embark on managing energy usage through promoting lower consumption and through the efficient and sustainable usage of energy. Eskom had to serve as the leaders in managing the energy usage. This took the form of developing and implementing energy management programmes, including programmes for Eskom employees. The literature research reviewed local and international approaches to Environmental and Energy Management programmes within organisations. A survey and quantitative analysis was undertaken to determine the perceptions of Energy Management Programmes by employees based at Eskom, New Germany. The population at Eskom New Germany consists of 758 employees. In total, 84 responses were received and analysed. The findings of the study indicated that the majority of respondents were aware of Eskom’s overall environmental and energy management programmes. The majority of respondents positively rated these programmes in terms of their incentives, motivation, effectiveness, support structures and communication channels. Regarding the overall energy management programmes implemented at Eskom, New Germany, the majority of the respondents were aware of them and were of the view that these programmes were very effective. One programme had a poor participation level mainly due to lack of awareness, but the respondents who did participate indicated that the programme was valuable in terms of its effectiveness. The main recommendation was to combine all the energy management programmes into one portfolio, driven by one department. This Department will be responsible for the developing, implementing and sustaining current and future energy management programmes for employees within Eskom. / Thesis (MBA)-University of KwaZulu-Natal, Durban, 2012.
26

The impact of supplier quality management on Eskom's Eastern Region power network operations.

Asmal, Riaz. January 2011 (has links)
South Africa’s national power utility, Eskom, procures products and services from a multitude of suppliers for its operations. Annually, Eskom’s Eastern Region spends approximately two billion rand on the procurement of products and services for its power network operations. Considering the expenditure, what is the effect of supplier quality management on Eskom’s operations? The aim of this study was to determine the impact of supplier quality management on Eskom’s Eastern Region’s power network operations. A multi methods approach was used for this study which included quantitative data and phenomenological interviews. For the past two financial years, Eskom’s Eastern Region procured R2.7billion worth of products and services from 187 suppliers for its operations. A probability sample of 82 suppliers was drawn from this population. The sample was composed of 58% electrical construction companies, 20% product manufacturers, 17% consulting engineers and 5% electrical hardware distributors. Data was collected using an email questionnaire developed by the researcher. Structured phenomenological interviews on supplier quality management were conducted with 41 employees of Eskom’s Field Services Department. These employees were chosen as they are directly accountable for managing network operations and are end-users of suppliers’ products and services. Significantly, the statistical analysis and the outcome of the phenomenological interviews revealed points of convergence and divergence between the stated positions of the suppliers and the actual experience of Eskom’s employees on quality of products and services. By combining the quantitative and qualitative dimensions of this study, the analysis illustrated the existence of cavernous gaps between suppliers and actual experience of Eskom employees on quality management areas such as suppliers’ commitment to product and service quality, focus on customer satisfaction, effective quality control and network operations. Several elements of the suppliers’ quality management programmes don’t meet Eskom’s expectations. The results of the study can benefit both suppliers and Eskom in identifying aspects of quality management that are negatively impacting operations and recommends areas of improvement. / Thesis (MBA)-University of KwaZulu-Natal, Durban, 2011.
27

The alignment of espoused values and organisational culture at a South African parastatal organisation

Phale, Robert Aubrey 06 June 2012 (has links)
M.Comm. / The primary purpose of the present study was to identify whether the organisational culture of the Transmission Division of Eskom is aligned to its stated values. In seeking to reach this objective, it was necessary to assess the gap between espoused and practised organisational values. The study also sought to identify the Transmission Division’s organisational culture. A correlation between the stated values and identified organisational culture was calculated and this was used to infer whether the values that the organisation espouses are aligned to the current organisational culture. The study made use a self-administered questionnaire sent via email to all the Transmission Division employees (N=1793) of whom 182 responded. The questionnaire comprised sections covering biographical aspects, organisational values as well as questions on organisational culture. In the questionnaire, biographical aspects were provided by the Transmission Division’s human resources department and those for organisational values were derived from both literature and Eskom’s value statement. Questions on organisational culture were taken from Cameron and Quinn’s (2006) Organisational Culture Assessment Instrument (OCAI). Data on organisational values was subjected to quantitative analysis whilst data relating to organisational culture was interpreted by following Cameron and Quinn’s (2006) Competing Values Framework (CVF). The present study found that there is a gap between observed and espoused or stated organisational values. By using the Cameron and Quinn (2006) framework of organisational culture, which identifies hierarchy, ‘adhocracy’, market and clan’ as the ‘four distinct organisational culture types, the study found that respondents experience the current Transmission Division’s organisational culture to be predominantly hierarchical. A general inference drawn in this study is that the current hierarchical organisational culture is misaligned to the espoused organisational values of ‘integrity’, ‘customer satisfaction’, ‘innovation’ and ‘excellence’. The study makes recommendations to the Transmission Division about how to address this misalignment and areas that require further investigation are suggested.
28

Development of a Fire-induced Flashover Probability Index (FIFPI) for Eskom transmission lines

Frost, Philip Edward 03 May 2012 (has links)
M.Sc. / The need for a fire-induced flashover (power line arcing to the ground) probability index for Eskom transmission (high voltage power) lines became evident soon after the installation the Advanced Fire Information System (AFIS) in 2004. AFIS is a satellite based fire detection system that utilizes polar and geostationary satellite sensors to detect fires as small as 50 m x 50 m in size. As soon as a fire is detected by either, the Terra, and Aqua Moderate Resolution Imaging Spectro-radiometer (MODIS) or Meteosat Second Generation (MSG) geostationary satellites close to any of the 28 000 km of Eskom transmission lines, a cell phone and email text warning is sent out to line managers responsible for the management of the particular section of line affected. Between 3000 - 6000 fires are recorded annually close to Eskom transmission lines with a fire-induced flashover rate of 100 - 150 transmission line trips per year. Fire-induced flashovers occur when the air around high voltage transmission lines are ionised due to a hot flame (> 500° C). As the air becomes conductive, electricity can move from the line to the ground in the form of a lightning flash. Studies have shown that one flashover can cause an average of three voltage depressions (dips) on the electrical transmission system, and each voltage depression can cause damage to a customer’s production ranging between R5000 and R150000 per dip. The aim of this study was to develop a prediction model with the ability to accurately predict fire-induced flashover occurrences on Eskom transmission lines in order to reduce the large amount of false alarms (SMS and email messages) produced annually by AFIS. The prediction model in the form of a probability index was derived from a combination of remote sensing satellite products as well as weather forecast variables. With the MODIS active fire product as base layer, weather forecast variables in the form of air temperature, relative humidity, wind speed and wind direction, as well as topographical elevation and a satellite derived vegetation condition product served as input to the predictor data set of the model, while flashover statistics for 2007 provided the target data set within a Classification and Regression Tree (CART) analysis. iii The prediction capabilities for each of the variables were evaluated based on their prediction accuracy and Receiver Operation Characteristic (ROC) value in terms of the validation data set. Wind speed, relative humidity, wind direction and air temperature were shown to have the highest predictor importance and were used to develop the probability index calculated from a logistic regression analysis. The Fire-induced Flashover Probability Index (FIFPI) was tested through simulations of predictor variables and was also compared to existing Fire Danger Indices (Willis et al. 2001). The FIFPI was able to outperform most of the standard Fire Danger Indices (FDI’s) with only the McArthur Grassland Index (MK 4) which demonstrated some prediction capability. The importance of wind direction as an environmental component in the prediction of flashovers became clear as it tended to decrease the misclassification rate from 4.45% when only wind speed, relative humidity and temperature were used to 3.87% when wind direction was added. The research has shown that wind speed, wind direction, relative humidity and temperature can be used as an indicator of possible fire-induced flashovers underneath Eskom transmission lines. However, additional research is needed to verify the results from 2007. Ideally at least 3 years of data should be used.
29

Development of a project management maturity measurement model to evaluate project management efficiency in a large parastatal

Mapane, Mohau 04 June 2012 (has links)
M.Ing. / The aim of this research is to develop a Project Management Maturity Measurement Model to evaluate project management efficiency in a large Parastatal such as Eskom Distribution. This model will identify areas of improvement to assist a large Parastatal in improving their project management performance. It will eventually assist the organisation to build a culture of project management excellence. The hypotheses for the study were that firstly, the Parastatal does implement project management practice processes as advocated by project management bodies of knowledge. Secondly, a Project Management Maturity Measurement Model can be successfully implemented at a large Parastatal and help the Parastatal to identify project management grey areas that require improvement. Thirdly, a Project Management Maturity Measurement Model could assist a large Parastatal with project management improvement as a result of areas of recommendations. The method used to collect the required data for analysis and interpretation was the descriptive survey method. A customised survey questionnaire was developed to obtain data from research sample. Data was analysed using appropriate statistical techniques. The research sample was defined as the people who are primarily responsible for project, programme and portfolio management at a large Parastatal. The results of the data analysed pin pointed project management process weaknesses and possible improvement opportunities. Three main areas of improvement have been identified, namely applying lessons learned from previous project into future project, performing benchmarking to improve performance and project control processes. The findings of this study support the abovementioned hypotheses, and the insights provided and recommendations made will be of great help to a large Parastatal on its road to continuous improvement and building a culture of project management excellence.
30

A case study on the development of an asset management process within the Eskom fossil fired power stations with emphasis on the reliability basis optimisation process

Singh, Shanil Narain 05 June 2012 (has links)
M.Ing. / This dissertation deals with the implementation of a Reliability Basis Optimisation Process for Eskom’s fossil fired Power Stations. This study comes about as a result of the situation that Eskom currently finds itself in. Eskom currently has a generating capacity of 41 000MW. It supplies 95% of South Africa’s power requirements and 45% of Africa’s power requirements. With the unprecedented economical growth that South Africa has experienced in the last five years, coupled with the economic recession of 2008/2009, Eskom has found itself in a precarious position in terms of power delivery. Eskom’s request for a 45% tariff increase in its Multi Price Determination (MYPD2) application to NERSA was turned down and a figure of 25% was awarded. Eskom’s current reserve margin is currently lies as less than 10%. With the funding restrains it now becomes difficult to replace machinery as it fails. The focus now shifts of carrying out effective maintenance. Eskom established the Asset Management Department with a view to ensure that the right maintenance was carried out. Within the Asset Management Department the Reliability Basis Optimisation (RBO) Process was established. The aim of the RBO stream is to improve the reliability and availability of the fossil fired Power Station. This dissertation looks at how the RBO process was developed and rolled out to the Power Stations. It also gives a brief overview of the Asset Management Improvement process to which the RBO process is the backbone.

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