| Summary: | Thesis (PhD)--University of Stellenbosch, 2002. === ENGLISH ABSTRACT: The dissertation presents an alternative approach to the control of power electronic
converters. The conventional approach is to use a centralized controller with one or
more measurement systems providing feedback. As converters become larger, in both
power rating and complexity, a number of drawbacks to this approach emerge. The
number of physical data paths increases and voltage isolation becomes a problem.
This has an adverse effect on the manufacturability as well as the reliable operation of
the system as a whole. An alternative is to use a distributed control approach, where a
number of smaller integrated control and measurement units are used. These units
communicate with the central controller via a serial daisy-chain communications link.
The dissertation investigates the design of such a controller as well as the application
of distributed control in a number of emerging converter topologies. It was shown
that centralized control has its limitations in modem power electronics in terms of
reliability, maintainability and manufacturability. A feasible distributed control
strategy was proposed and implemented and the operation was verified in an
experimental converter system. === AFRIKAANSE OPSOMMING: Die proefskrif ondersoek 'n alternatiewe manier om drywings omsetters te beheer.
Huidiglik word die meerderheid van omsetters beheer vanaf 'n sentrale
beheereenheid, wat dan stelsel data versamel vanaf een of meer meetstelsels. Soos die
drywingsvermoë van die omsetters toeneem, raak spannings isolasie en die aantal
beheerseine 'n probleem, wat nadelig is vir die betroubaarheid en vervaardigbaarheid
van die stelsel. As 'n alternatief, kan 'n aantal kleiner beheereenhede en meetstelsels
gebruik word. Die beheerders kommunikeer met mekaar, sowel as die hoof
stelselbeheerder deur middel van 'n optiese vesel netwerk, verbind in 'n ring
struktuur. Die proefskrif ondersoek die ontwerp van die beheerder en die toepassing
van gedesentraliseerde beheer in 'n aantal nuwe omsetter topologië. Die studie toon
dat sentrale beheer problematies kan raak soos die omsetters meer kompleks raak.
Die studie bewys dat 'n stelsel suksesvol bedryf kan word deur gebruik te maak van
gedesentraliseerde beheer deur dit in 'n praktiese opstelling toe te pas.
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