Thesis (MScEng)--University of Stellenbosch, 2003. / ENGLISH ABSTRACT: This thesis presents the design and implementation of shunt active power filtering algorithms for
unbalanced, non-linear loads.
A three-phase four-wire topology is developed in the dqO space. Based on this development an accurate
dynamic system model, taking into account the effect of the neutral inductor is developed.
The synchronous reference frame technique is expanded to enable the isolation of the zero sequence
current component into its instantaneous active and reactive current components. Additionally a
prediction method is proposed that will enable the proper prediction of the reference currents in a threephase
four-wire system.
Two categories of reference current signal tracking algorithms are investigated; namely the predictive
current controller and the sliding mode current controller. A compensating technique is proposed to
compensate for the effects that sampling and computational time delay have on the performance of the
system. Additionally, an investigation is done into the effect that dead-time has on the performance of the
system, and based on this investigation a dead-time compensating strategy is proposed.
Finally simulation and practical results are provided to validate the discussed theories. / AFRIKAANSE OPSOMMING: Hierdie verhandeling ondersoek die ontwerp en implementering van parralel gekoppelde aktiewe filter
algoritmes vir ongebalenseerde, nie-lineêre laste.
'n Drie-fase vier-draad topologie, asook 'n korrekte model van die dinamiese sisteem, wat die effek van
die neutraal induktor insluit, is ontwikkel in die dqO ruimte. Die sinchroon verwysing vlak tegniek is
uitgebrei om die isolering van die nul sekwensie stroom in onderskeidelik die oombliklike aktiewe en
reaktiewe stroom komponente te verdeel. Addisioneel is a vooruitskatting tegniek aanbeveel wat die
beheerder in staat sal stelom voldoende die verwysing strome vooruit te skat in 'n drie-fase vier-draad
stelsel.
Twee katagoriee van verwysing stroom volging algoritmes is ondersoek, naamlik die afskatting stroom
beheerder en die gleiende modus stroom beheerder. 'n Effektiewe kompensasie tegniek is voorgestel
om die effek van tydvertraging as gevolg van monstering en verwerking te elimineer. Addisioneel is die
effek van dooie-tyd ondersoek en gebasseer op hierdie ondersoek is 'n effektiewe dooie-tyd
kompensasie tegniek voorgestel.
Laastens is simulasies en praktiese resultate verskaf om die werking van die voorgestelde teorie te
bevestig.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/53589 |
| Date | 12 1900 |
| Creators | Gous, Marthinus Gerhardus Faculin |
| Contributors | Beukes, H. J., Stellenbosch University. Faculty of Engineering. Dept. of Electrical and Electronic Engineering |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | Unknown |
| Type | Thesis |
| Format | 188 p. : ill. |
| Rights | Stellenbosch University |
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