Thesis (MEng)--University of Stellenbosch, 2000. / ENGLISH ABSTRACT: Recent advances in semiconductor device development pushed a large number of network devices onto the market. These devices can solve network problems more effectively and economically than ever before. Network planners need tools to analyse and implement such devices to help solve the largest network problem in South Africa: voltage regulation. Rural networks experience the majority of voltage-regulation problems in South Africa. The networks are long sub-transmission and reticulation networks and are modelled by two generic networks, namely a radial network and a two-source ring network. The equations describing voltage regulation for the generic networks are developed and implemented in PSAT, a software analysis tool. The voltage regulation for two case studies that represent the two generic networks are analysed. Four generic network devices are defined and various control methods for these devices are developed to solve the network problem. The aim of PSAT is to help the network planner to quickly evaluate a number of possible solutions and to choose the best solution for further studies. This is demonstrated with the aid of the case studies. PSAT provides a sturdy platform on which future developments, such as stability analyses, can be built. However, PSAT can already function as a stand-alone analysis tool to solve voltage regulation as a network problem. / AFRIKAANSE OPSOMMING: Onlangse vooruitgang in halfgeleier ontwikkeling het 'n groot aantal netwerktoestelle op die mark geplaas. Hierdie toestelle kan netwerk probleme doeltreffender en meer ekonomies oplos as ooit vantevore. 'n Behoefte aan 'n pakket wat netwerkbeplanners in staat stelom die netwerktoestelle te analiseer, is geïdentifiseer. So 'n pakket sal hulle help om die vernaamste netwerkprobleem in Suid-Afrika, nl. spanningsregulasie, op te los. Die oorgrote meerderheid spanningsregulasie probleme word op die platteland ondervind. Plattelandse netwerke word gekenmerk deur lang sub-transmissie en retikulasie netwerke. Hierdie netwerke word met behulp van twee generiese netwerke gemodelleer. 'n Radiale netwerk en 'n dubbelbron ringnetwerk word aangewend om enige plattelandse netwerk te analiseer. Vergelykings is vir spanningsanalise ontwikkel en in PSAT, 'n analitiese sagteware pakket, geïmplementeer. Twee gevallestudies is gedoen om die twee netwerke afsonderlik voor te stel en die vergelykings van PSAT te evalueer. Alle netwerktoestelle is in een van vier generiese kategorieë geklassifiseer. Modelle is vir elk van die kategorieë ontwikkel vtr spanningsregulasie analise. Die doel van PSAT is om die netwerk beplanner te help om vinnig en effektief soveel moontlik opsies te ondersoek as oplossings vir 'n spesifieke netwerk probleem. PSAT is reeds 'n alleenstaande pakket wat in die toekoms uitgebrei sal word om na die analise van stabilitietsprobleme te kyk.