Browsing by Author "Prinsloo, Gerhardus Johannes"

Now showing 1 - 4 of 4
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    Automatic positioner and control system for a motorized parabolic solar reflector
    (Stellenbosch : Stellenbosch University, 2014-12) Prinsloo, Gerhardus Johannes; Dobson, R. T.; Schreve, K.; Stellenbosch University. Faculty of Engineering. Department of Mechanical and Mechatronic Engineering.
    ENGLISH ABSTRACT: Most rural African villages enjoy high levels of sunlight, but rolling out solar power generation technology to tap into this renewable energy resource at remote rural sites in Africa pose a number of design challenges. To meet these challenges, a project has been initiated to design, build and test/evaluate a knock down 3 kW peak electrical stand-alone self-tracking dual-axis concentrating solar power system. This study focusses on the mechatronic engineering aspects in the design and development of a dynamic mechatronic platform and digital electronic control system for the stand-alone concentrating solar power system. Design specifications require an accurate automatic positioner and control system for a motorized parabolic solar reflector with an optical solar harnessing capacity of 12 kWt at solar noon. It must be suitable for stand-alone rural power generation. This study presents a conceptual design and engineering prototype of a balanced cantilever tilt-and-swing dual-axis slew drive actuation means as mechatronic solar tracking mobility platform for a ∼12 m2 lightweight parabolic solar concentrator. Digital automation of the concentrated solar platform is implemented using an industrial Siemens S7-1200 programmable logic controller (PLC) with digital remote control interfacing, pulse width modulated direct current driving, and electronic open loop/closed loop solar tracking control. The design and prototype incorporates off-the-shelf components to support local manufacturing at reduced cost and generally meets the goal of delivering a dynamic mechatronic platform for a concentrating solar power system that is easy to transport, assemble and install at remote rural sites in Africa. Real-time experiments, conducted in the summer of South Africa, validated and established the accuracy of the engineering prototype positioning system. It shows that the as-designed and -built continuous solar tracking performs to an optical accuracy of better than 1.0◦ on both the azimuth and elevation tracking axes; and which is also in compliance with the pre-defined design specifications. Structural aspects of the prototype parabolic dish are evaluated and optimized by other researchers while the Stirling and power handling units are under development in parallel projects. Ultimately, these joint research projects aim to produce a locally manufactured knock down do-it-yourself concentrated solar power generation kit, suitable for deployment into Africa.
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    Dynamic vocal tract features for the recognition of coarticulated vowels
    (Stellenbosch : Stellenbosch University, 1993) Prinsloo, Gerhardus Johannes; Stellenbosch University. Faculty of . Dept. of .
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    Phoneme class recognition and automatic syllabification with a phonological based hidden Markov model
    (Stellenbosch : Stellenbosch University, 1988) Prinsloo, Gerhardus Johannes; Stellenbosch University. Faculty of . Dept. of .
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    Synthesis of an off-grid solar thermal cogeneration and intelligent smartgrid control system for rural applications
    (Stellenbosch : Stellenbosch University, 2018-03) Prinsloo, Gerhardus Johannes; Dobson, Robert Thomas; Brent, Alan C.; Perold, Willem ; Stellenbosch University. Faculty of Engineering. Dept. of Mechanical and Mechatronic Engineering.
    ENGLISH SUMMARY: Access to reliable, affordable, and modern energy services has a vital role to play in attaining the Sustainable Development Goals promulgated by the United Nations, since this factor directly impacts on 74 % of their associated overall targets. With 80 % of the global energy-impoverished population living in rural areas, it is crucial to reach these communities to solve the global energy access problem. Sub-Saharan Africa is of particular concern as 16 of the 20 high-impact countries (lowest electrification rates) are located in this region, with current endeavours not able to keep up with population growth. Microgrids are critical in solving this problem, with about 44 % of the rural Sub-Saharan Africa population gaining access to electricity by 2040 expected to be connected by microgrids. This study identifies the need for advanced village microgrid control governance to fulfil the role of smart energy systems of future Smart Villages. While R&D pathways for future Smart Grid microgrids in the Global North are well defined, there are no definitive pathways for the development of advanced microgrids in the rural village landscape of the Global South. This dissertation hypothesises that rural village microgrids should adopt their operating principles from state-of-the-art future Smart Grid developments, and tailor these to address the knowledge gap pervading in the rural village microgrid landscape. This hypothesis is based on observations of global energy market trends that indicate a likely convergence in operating methods between Smart Village and Smart City energy systems. This study applies a model-based design-thinking methodology to the conceptualisation process of a proposed microgrid platform suitable for future Smart Village microgrids. This steered the development process to observe the challenges to rural electrification from the perspective of the village energy user as the primary stakeholder while formulating a concept platform based on future Smart Grid operating principles. This study combines state-of-the-art microgrid control principles, based on transactive energy management, with innovative methods that allow for functional interaction between the microgrid system and energy prosumers in the rural village. This dissertation thus establishes the interactive-marketbased- control (i-MBC) approach at the core of the proposed next-generation Smart Village microgrid platform. The feasibility of this unique approach is demonstrated in synthesis experiments, using rural Smart Village case-based challenge scenarios. In addition to the current energy market drivers and trends that support this hypothesis, this research presents additional evidence to support the philosophy that Smart Village microgrids and Smart City microgrids can, to a large extent, share the same developmental pathway. A firm standpoint on the future of rural village microgrids is taken, as reflected and confirmed in the proposals for the Smart Village microgrid platform. This standpoint gives clear directives on the overlapping principles of Smart Cities and Smart Villages that will help researchers and energy access practitioners to select aspects of a Smart Grid R&D development program that is relevant to Smart Village microgrids.