Now showing items 1-10 of 10

    • Application of maintenance tools and strategies in integrated risk management of critical physical assets. 

      Mkandawire, Burnet O'Brien.; Ijumba, Nelson M.; Whitehead, Howard. (Inderscience Publishers., 2011)
      This paper critically analyses various tools, techniques and strategies; and proposes an ‘integrated risk management model’ that utilises advantages of the best combination of tools, techniques and strategies to manage ...
    • Asset management optimization through integrated systems thinking and N-1 contingency capability for refurbishment. 

      Ijumba, Nelson M.; Whitehead, Howard.; Mkandawire, Burnet O'Brien. (Institute of Electrical and Electronics Engineers., 2011-09)
      This paper presents a systems view of refurbishment systems to evaluate root causes of suboptimal refurbishment. Case studies from ten selected South African and Malawian firms from largest electric power utilities, mining, ...
    • Eskom’s proposed strategic research into HVDC transmission. 

      Naidoo, Pat.; Bologna, F. F.; Muftic, Dzevad.; Ijumba, Nelson M.; Britten, Anthony C.; Pillay, Logan. (EE Publishers., 2005-07)
      Eskom has recently started a large research and development programme for the study of long-distance HVDC transmission in Sub-Saharan African conditions. This paper explains why the research is being done, what its strategic ...
    • Modelling of broadband powerline communication channels. 

      Mulangu, Chrispin Tshikomba.; Afullo, Thomas Joachim Odhiambo.; Ijumba, Nelson M. (SAIEE Publications., 2011-12)
      This paper develops a new PLC model and investigates the impact of the load, line length, and diameter of the transmission line on the channel transfer function over the frequency range of 1-20 M Hz. The results show that ...
    • Quantitative Feedback Theory design of line current commutated HVDC control systems. 

      Chetty, Leon.; Ijumba, Nelson M. (SAIEE Publications., 2013)
      Line Current Commutated (LCC) HVDC systems consists of uncertain plants. These uncertainties are result of changes/disturbances in the ac networks or in the LCC HVDC system itself. Further uncertainties can be introduced ...
    • Rural electrification using overhead HVDC transmission lines. 

      Chetty, Leon.; Ijumba, Nelson M. (Energy Research Centre., 2012)
      One of mankind’s greatest modern challenges is poverty alleviation. The provision of electricity can greatly assist in this regard. The tapping of small amounts of power from an HVDC transmission line represents a solution ...
    • Safety of low voltage switchgear assemblies in South Africa – Part 1. 

      Bonner, Mark James.; Ijumba, Nelson M. (EE Publishers., 2005-10)
      A technical analysis was undertaken to investigate the safety implications of the introduction of the category Specially Tested Assembly (STA) into the South African standard SANS 1473-1:2003. The testing requirements ...
    • Safety of low voltage switchgear STAs in South Africa – Part 2. 

      Bonner, Mark James.; Ijumba, Nelson M. (EE Publishers., 2005-11)
      This article is Part 2 of a two part article. Part 1 was published in the October 2005 issue of ENERGIZE. A technical analysis was undertaken to investigate the safety implications of the introduction of the category ...
    • Suppression of transients across the tap windings of an auto-transformer. 

      Buthelezi, N. V.; Ijumba, Nelson M.; Britten, Anthony C. (EE Publishers., 2005-06)
      For the energy transfer between the various voltage levels of the Eskom national grid, auto-transformers are mainly installed. These auto-transformers are interfaced with the distribution network.
    • System identification of classic HVDC systems. 

      Chetty, Leon.; Ijumba, Nelson M. (SAIEE Publications., 2011-12)
      Determining models from observations and studying the models’ properties is essentially the functionality of science. Models attempt to link observations into some pattern. System identification is the art of building ...