Thesis (MScEng)--University of Stellenbosch, 2000. / ENGLISH ABSTRACT: Once more opportunities exist for innovative technologies to be applied on MV and LV power distribution networks to meet the new challenges set by government through its National Electrification Programme (NEP) to electrify a further 2,5 million households of which a large majority are in low-density rural areas. Electronic means of voltage compensation of long MV and LV networks supplying these low-density rural areas are now possible in the form of electronic voltage regulators mounted on the secondary side of distribution transformers and service connection boxes along the LV feeders. Furthermore, it is now possible to provide remote rural agricultural customers with singlephase supplies supported by end-use technologies in the form of electronic phase converters that eliminate the need for three-phase supplies. This hybrid of supply- and end-use technologies together with Eskom's "self-build" policy has made the dream of Eskom grid power a reality. / AFRIKAANSE OPSOMMING: Nuwe geleenthede het na yore getree vir die toepassing van innoverende tegnologie op medium- en laagspannings netwerke in antwoord op die uitdagings gestel deur die regering in die vorm van die Nasionale Elektrifiseringsprogram (NEP). Die elektrifisering van 'n verdere 2,5 miljoen huishoudings waarvan die grootste gedeelte in yl bevolkte plattelandse gebiede is, word in vooruitsig gestel. Spanningskompensasie van lang laag- en mediumspannings netwerke word nou moontlik gemaak deur middel van elektroniese spanningsreguleerders, gemonteer aan die sekondere kant van distribusie transformators en in diensaansluitingskaste op laagspannings voerders. Verder is dit ook nou moontlik om afgelee landelike plase met enkelfase krag, gerugsteun deur eindverbruik tegnologie in die vorm van elektroniese fase omsetters, te voorsien. Die beskikbaarheid van hierdie tegnologie elimineer die vraag na drie-fase krag. Hierdie hibriede kombinasie van toevoer- en eindverbruik tegnologie in kohesie met die selfbou beleid van Eskom, maak dit moontlik dat 'n droom van Eskom voorsiende elektrisiteit, in 'n werklikheid omskep word.

Thesis (MEng)--University of Stellenbosch, 2000. / ENGLISH ABSTRACT: This thesis deals with different design aspects of the multi-flux barrier rotor of the reluctance synchronous machine (RSM). The effect of the different designs on the performance of the RSM is investigated by means of two-dimensional finite element analysis. The finite element analysis is also directly used in the optimum design of the rotor of the RSM. The importance of the use of the finite element analysis in the design and performance calculations of the RSM is illustrated in this thesis. The design aspects of the RSM which are focussed on in this thesis are, amongst other things, the chording of the stator winding, the skewing of the rotor and the ratio of the number of rotor flux barriers to the number of stator slots of the RSM. The effects of these design aspects on the average torque and torque ripple of the RSM are investigated and general design directives are given. The occurrence of flux pulsations in the stator teeth and rotor iron segments of the RSM are also studied to some extent. The finite element optimum design of a4-pole RSM-rotor with a high number of flux barriers is described in the thesis. This optimum designed rotor is built and the RSM with this rotor is tested in the laboratory. Its calculated and measured performances are studied and compared with a conventional, low number rotor flux barrier RSM. It is found, amongst other things, that the RSM with the high number of rotor flux barriers has a slightly higher average torque with a significantly lower torque ripple. / AFRIKAANSE OPSOMMING: Hierdie tesis handeloor verskillende ontwerp-aspekte van die reluktansie sinchroonmasjien (RSM) met 'n multi-vloedversperringsrotor. Die effek van die verskillende ontwerpe op die vermoë van die RSM is met behulp van twee-dimensionele eindige element analise ondersoek. Die eindige element analise is ook direk in die optimum ontwerp van die rotor van die RSM gebruik. Die belangrikheid van die gebruik van die eindige element analise in die ontwerp en vermoë-berekening van die RSM word in die tesis geïllustreer. Die ontwerp-aspekte van die RSM waarop in hierdie tesis gefokus word, is onder andere die spoelsteekverkorting van die statorwikkeling, die skuinsing van die rotor en die verhouding van die getal rotor-vloedverperrings tot die getal statorgIeuwe van die RSM. Die effek van hierdie ontwerpaspekte op die gemiddelde draaimoment en draaimoment-rimpel van die RSM word ondersoek en algemene riglyne vir die ontwerp van die RSM word gegee. Die voorkoms van vloedpulsasies in die statortande en rotor yster segmente van die RSM word ook deels ondersoek. Die eindige element optimum ontwerp van 'n 4-pool RSM-rotor met 'n hoe getal vloedversperrings word in die tesis beskryf. Hierdie optimum ontwerpte rotor is gebou en die RSM met hierdie rotor is in die laboratorium getoets. Die berekende en gemete vermoë is bestudeer en vergelyk met die vermoë van 'n RSM met 'n konvensionele, lae getal vloedversperrings rotor. Dit is onder andere gevind dat die RSM met die hoë getal rotor-vloedversperrings 'n effens hoër gemiddelde draaimoment het met 'n behuidende laer draaimoment-rimpel.

Thesis (MScEng)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: Recent advances in semiconductor technology extended the economic power range for DC transmission to just a few MW. Network planners need tools to compare AC and DC alternatives in order to find the best technical and economic solution for a specific network. TESAT, a software analysis tool, is developed to determine the optimum conductor and line technology for a network. Voltage regulation problems are identified and can be solved with network devices which have the potential to solve network problems more effectively and economically than ever before. PSAT, another software analysis tool developed in previous research, is used to model networks and support technologies. Hence, with the aid of TESAT and PSAT, line and support technologies are combined in an attempt to find the most effective solution in terms of cost and technical performance. This is demonstrated with the aid of a case study. Furthermore, interfaces between PSAT and the real world are developed. This includes an extension to the input interface of PSAT that calculates the equivalent impedances of a transmission line automatically, as well as an interface to share data between ReticMaster and PSAT. A dispersed generation and support technology database is also developed as an extension to the output interface ofPSAT. / AFRIKAANSE OPSOMMING: Onlangse vooruitgang in halfgeleiertegnologie het tot gevolg dat GS transmissie ekonomies is vir slegs 'n paar MW. Netwerkbeplanners benodig gevolglik pakette om WS en GS alternatiewe te vergelyk vir 'n spesifieke netwerk. In hierdie tesis is 'n analitiese sagteware-pakket (TESAT) dus ontwikkelom die optimale geleier en lyntegnologie VIr 'n netwerk te bepaal. Spanningsregulasie-probleme word geïdentifiseer en opgelos met netwerktoestelle wat die potensiaal het om netwerkprobleme meer doeltreffend en ekonomies as ooit tevore op te los. PSAT, 'n ander analitiese sagteware-pakket wat in vorige navorsing ontwikkel is, word dan ook gebruik om netwerke en steuningstegnologieë te modelleer. Dus word PSA T en TESA T gebruik om lyn- en steuningstegnologieë te kombineer. Die doel hiervan is om die mees doeltreffende oplossing in terme van kostes en tegniese werksverrigting te vind. Dit word met behulp van 'n gevallestudie gedemonstreer. Verder word koppelvlakke tussen PSA T en die eksterne wêreld ontwikkel. Dit sluit in: (a) 'n uitbreiding van die intreekoppelvlak van PSAT wat die ekwivalente impedansie vir 'n transmissielyn outomaties bereken; (b) die koppelvlak om data te deel tussen PSAT en ReticMaster. 'n Verspreide generasie- en steuningstegnologie databasis is uiteindelik ook ontwikkel as 'n uitbreiding van die uittreekoppelvlak van PSAT.

Thesis (MScEng)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: In this thesis a new voltage control method is developed for a three-phase inverter supply system. The inverter supply system consist of a Permanent Magnet Generator, a three-phase rectifier, a three-phase inverter plus LC-filter and a three-phase transformer in series. This system supplies power to a network or to a stand-alone load. The main focus of this thesis is on the control aspects of the inverter and the LC-filter. Different voltage control systems are investigated and compared to each other. From these methods the proposed voltage control method is developed where only the output voltages are measured to establish good voltage control. All these voltage control methods are also simulated with a software package. The proposed voltage control method compares very well with other voltage control methods. The results that are obtained in the simulations are satisfactory. The proposed voltage control method is also implemented in an 8 kW laboratory scale model and, again, very good practical results are obtained. A TMS320F240 nsp controller is used to implement the proposed voltage control method. The controller compensates well for load steps, and these results compare well to an alternative voltage control method, which was also evaluated practically. / AFRIKAANSE OPSOMMING: In hierdie tesis IS 'n nuwe spanningsbeheermetode ontwikkel VIr 'n drie-fase wisselrigter kragtoevoerstelsel. Die wisselrigter kragtoevoerstelsel bestaan uit 'n Permanent Magneet Generator, 'n drie-fase gelykrigter, 'n drie-fase wisselrigter plus Le-filter, en 'n drie-fase transformator in serie. Hierdie stelsel voorsien krag aan 'n netwerk sowel as aan 'n alleenstaande las. Die hooffokus van hierdie tesis is op die beheeraspekte van die wisselrigter en Le-filter. Verskillende spanningsbeheermetodes is deeglik ondersoek en vergelyk met mekaar. Uit hierdie metodes is dan die voorgestelde beheermetode ontwikkel waar slegs die uittreespanning gemeet word om goeie spanningsbeheer te kan doen. Al hierdie spanningsbeheermetodes is dan gesimuleer met 'n sagteware pakket. Die voorgestelde spanningsbeheermetode vergelyk baie goed met die ander spanningsbeheermetodes. Die resultate verky in die simulasies is ook baie bevredigend. Die voorgestelde beheermetode is ook geïmplementeer op 'n 8 kW laboratorium skaalmodel en weereens is baie goeie praktiese resultate verky. 'n TMS320F240 DSP-beheerder is gebruik om die voorgestelde beheermetode mee te implementeer. Die beheerder kompenseer baie goed vir lastrappe en vergelyk ook goed met 'n ander spanningsbeheermetode wat prakties ge-evalueer is.

Thesis (MScEng)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: This thesis presents the design and implementation of a voltage controller for an Uninterruptible Power Supply (UPS) Inverter. The inverter is capable of producing a nearly sinusoidal output voltage waveform, thereby keeping the Total Harmonic Distortion (THD) to a minimum. Digital controllers introduce a time delay in the control law that causes system instability. Various control techniques, which includes Pade approximations and system augmentation, are investigated to eliminate the effect of the time delay. These controllers employ classical control as well as modem control techniques. The selection of the various control parameters is verified by mathematical equations. A load-disturbance compensation scheme, implementing feed-forward and gain scheduling, is also developed to improve voltage distortion when varying loads, such as non-linear loads, are connected to the system. It is shown that the constructed pulse-width modulated (PWM) control scheme can achieve fast dynamic response as well as a low THD. / AFRIKAANSE OPSOMMING: Hierdie verhandeling ondersoek die ontwerp en implementering van 'n spanningsbeheerder vir 'n ononderbroke kragtoevoer omsetter. Die stelsel produseer 'n uittree spannigsgolfvorm met 'n lae Totale Harmoniese Distorisie (THD). Digital beheerders veroorsaak 'n tydvertraging in die beheerwet wat stelsel onstabiliteit kan veroorsaak. Verskeie beheertegnieke wat gebaseer is op die Pade benaderings van die tydvertraging en stelsel aanpassings, is ondersoek. Hierdie beheerders maak gebruik van klassieke en moderne beheertegnieke. Die seleksie van die verskeie beheerderveranderlikes word gestaaf deur wiskundige vergelykings. Spannigsvervorming word tot 'n minimum beperk deur gebruik te maak van 'n lasveranderings-kompensasietegniek wat onderskeidelik vorentoe-voer en aanwins skedulering implementeer. Verder word daar bewys dat die pulswydte modulasie (PWM) beheerskema vinnige dinamiese gedrag asook 'n lae THD bewerkstellig.

Thesis (MScEng)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: This thesis presents results of a study on the small-signal stability of a single-machine infinite-bus power system. Conditions of generator loading and network impedance are identified that require additional stability support. Two methods of stability enhancement are investigated, namely the power system stabilizer and the controlled series capacitor. Both stabilizers employ the conventional (classic) control structure, and parameters are evaluated for optimum performance using an integral-of-the-squared-error-based method. Results for damping capability versus generator loading and system impedance were generated. The ability of the power system stabilizer and controlled series capacitor to provide stability support is compared. This comparison is based on (a) the ability to provide more damping torque when needed, and (b) the amount of damping torque contributed by the stabilizer. / AFRIKAANSE OPSOMMING: Hierin word die resultate van 'n studie op die klein-sein stabiliteit van 'n enkel-masjien oneindige-bus kragstelsel weergegee. Kondisies van generator belasting en netwerk impedansie waar dempings-ondersteuning benodig word, word geïdentifiseer. Twee metodes van stabiliteits-verbetering word ondersoek, naamlik die kragstelstel stabiliseerder en die beheerde serie kapasitor. Beide stabiliseerders maak gebruik van die konvensionele (klassieke) beheerstruktuur, waarvan parameters geëvalueer word deur gebruik te maak van 'n integraal-van-die-vierkant-fout-gebaseerde metode. Resultate vir dempingsvermoë teenoor generator belasting en stelsel impedansie word verkry. Die vermoë van die kragstelsel stabiliseerder en beheerde serie kapasitor om stabiliteits-ondersteuning te verskaf, word vergelyk. Hierdie vergelyking is gebasseer op (a) die vermoë om meer dempingswrinkrag te voorsien wanneer benodig, en (b) die hoeveelheid dempingswrinkrag deur die stabiliseerder bygedra.

Thesis (MScEng)--University of Stellenbosch, 2003. / ENGLISH ABSTRACT: This thesis discusses the analysis and design of a voltage regulator based on an AC-to-AC converter. A background study was performed on the best topology for the purpose. The chosen topology was analysed and the converter was designed in detail. A voltage sign-detector and an over-current detector were designed and built. They were used for control and protection. Three methods of control were investigated. The first was a slow but reliable method of computing the RMS value of the input voltage and then using that value and the RMS value of the desired output voltage to compute the duty ratio of the converter. The second method was fast and is an open-loop control method, where the measured input voltage and a reference value of the desired output voltage are used to compute the duty ratio. The third method is a closed-loop control method in which the input voltage, output voltage and the same reference values used in the second method are used to compute the duty ratio. All of these methods were implemented and tested. / AFRIKAANSE OPSOMMING: Hierdie tesis bespreek die analise en die ontwerp van 'n spannings reguleerder wat gebaseer is op 'n WS-na-WS omsetter. 'n Ondersoek was ingestelom die beste topologie te vind vir die doel. Die topologie wat gekies is, is toe geanaliseer en die omsetter is in detailontwerp. 'n Spannings-tekendetektor baan as ook 'n oorstroombeskermings baan was ontwerp en is gebou. Hierdie bane word gebruik vir die beheer en die beveiliging van die stelsel. Daar is drie metodes van beheer wat ondersoek is. Die eerste metode is stadig, maar betroubaar. Die metode bereken die WGK waarde van die intree spanning en gebruik dan die waarde en die WGK van die gewenste uittree spanning om die diens siklus van die omsetter uit te werk. Die tweede metode van beheer is vinnig en is 'n oop-lus metode van beheer. Hierdie metode maak gebruik van die gemete intreespanning en 'n verwysing van die gewensde uittree spanning om die dienssiklus uit te werk. Die derde metode is 'n geslote-lus beheer wat van die gamete intreespanning, die gemete uittreespanning en die verwysing soos die in die tweede beheermetode gebruik maak on die diens siklus uit te werk. AI die metodes was geimplementeer en getoets.

Thesis (MScEng)--University of Stellenbosch, 2003. / ENGLISH ABSTRACT: This thesis investigates the credibility of the vanadium redox flow energy storage system, sometimes termed vanadium redox battery (VRB). The focus is on the use of this technology in peak-shaving and load-leveling applications. The initial problem is to find a suitable mathematical model for representing the daily load profile. A sinusoidal function is identified as an elementary approximation of the first order. Due to the periodicity characteristics that are inherent in a daily load profile, the Fast Fourier Transform (FFT) algorithm is identified as a mathematical model that closely resembles a load profile. The main theme in this thesis is the determination of an optimal solution during the peak-shaving process. In this particular context, the optimal solution refers to the following: With the energy capacity of the VRB and the power rating of the entire system considered as the constraints, the interest is on (i) the constant power that the VRB can deliver in order to bring down the maximum demand quite significantly, (ii) and the time interval in which this constant power is delivered. Therefore, the VRB power delivered during peak-shaving (PVRB) and the corresponding time interval are the main two parameters under consideration in the optimization process. The mathematical algorithm that can be used to determine suitable values for these two parameters is developed. Maple" V 5.1 is used for determining the solution analytically. The obtained results are verified by simulation with Excel". The investigation into the economic benefits that may be derived from the utilization of the vanadium energy storage device is also presented. / AFRIKAANSE OPSOMMING: Hierdie tesis ondersoek die waarde en toepassing van die vadium "redox" vloei energie stoorstelsel (VRB). Die fokus is op die gebruik van hierdie tegnologie om pieklas te verminder en om laste meer egalig te maak. Die aanvanklike probleem is om 'n geskikte wiskundige model vir die daaglikse las-profiel te kry. Deur gebruik te maak van sinus-komponente en die toepassing van die Vinnige Fourier Transform (FFT) is hierdie probleem opgelos. Die hooftema van hierdie werk is om 'n analitiese oplossing te vind vir die optimale toepassing van die konsep vir pieklas vermindering. In hierdie konteks verwys die optimale oplossing na die volgende: Met die gegewe verrnoe van die VRB stelsel en drywingsvermoe van die kragelektronika is die vrae rondom (i) die konstante drywing wat die VRB kan lewer om die maksimum aanvraag van die las beduidend te verminder en (ii) die tydsduur waarin dit plaasvind. Dus is die twee veranderlikes waarvoor oplossings in die optimale proses gesoek word die drywing (PVRS) en die tyd-interval daarvan. Die wiskundige algoritme is met die hulp van Maple® V5.1 ontwikkel. Die resultate is daarna met behulp van simulasies in Excel® getoets. 'n Analise van die moontlike ekonomiese voordele is ook ondersoek.

Thesis (MScEng)--University of Stellenbosch, 2003. / ENGLISH ABSTRACT: This thesis describes the development of a GPS Based Time Stamping and Scheduling System for power system applications. These applications include Wide Area Measurements (WAMs) of electrical power system quantities and high-voltage transmission line fault location. The developed system employs a microcontrolIer and a GPS receiver to synchronise an onboard microsecond-accurate clock to a global time standard. The system is therefore able to provide an accurate GPS-synchronised time stamp of a received trigger signal for use in highvoltage transmission line fault location. The system is also able to generate a trigger signal at a pre-programmed time for initiation of data acquisition runs on electrical power systems. The system was constructed and tested in a laboratory environment. Although the system is designed to operate in stand-alone mode, a host computer software program was also developed for system control and data downloading. The software program was used to time stamp a number of trigger signals and data was downloaded to a host computer. Trigger signals were also generated at predefined times. The acquired data was validated and presented. In conclusion, the low system cost, relative to existing commercial systems, accuracy and programmability of the developed system makes it suitable for a wide variety of time-critical data acquisition applications. / AFRIKAANSE OPSOMMING: Hierdie tesis beskryf die ontwikkeling van 'n GPS gebaseerde tyd stempel en skedulerings sisteem met die oog op kragstelsel toepassings. Ingesluit by hierdie toepassings is wye area metings op elektriese kragstelsels, asook foutopsporing op hoogspanning transmissielyne. Die ontwikkelde sisteem gebruik 'n mikrobeheerder en 'n GPS ontvanger om 'n aanboord mikrosekonde-akkurate horlosie te sinkroniseer met 'n internasionale tyd standaard. Dus kan die ontwikkelde sisteem 'n akkurate GPS gesinkroniseerde tyd stempel aan 'n snellersein heg. Hierdie tyd stempel kan gebruik word in hoogspanning transmissielyn foutopsporing. Die sisteem kan ook 'n snellersein genereer op 'n vooraf geprogrammeerde tyd. Hierdie snellersein kan gebruik word om belangrike data van elektriese kragstelsels te versamel, deur gebruik te maak van bestaande dataversamelingstelsels. Die sisteem was ontwerp en getoets in laboratorium toestande. Alhoewel die stelselontwerp is om alleenstaande te funksioneer, is 'n beheer rekenaar gebruik om, met die hulp van ontwikkelde sagteware, die sisteem te beheer en data af te laai. 'n Tyd stempel is aan 'n aantal snellerseine geheg en hierdie data is afgelaai na 'n beheer rekenaar. Die sisteem is ook geprogrammeer om 'n aantal snellerseine te genereer op vooraf gedefinieerde tye. Die data wat uit hierdie toetse versamel is, is bespreek. In vergelyking met bestaande kommersiële stelsels is die ontwikkelde stelsel se lae koste, akkuraatheid en programmeerbaarheid eienskappe wat die stelsel geskik maak vir 'n wye verskeidenheid van tyd-kritieke dataversameling toepassings.

Thesis (MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The implementation of the Caprivi Link Interconnector (CLI) High Voltage Direct Current (HVDC) scheme in 2010 connecting the weak Namibian and Zambian Alternating Current (AC) transmission networks via overhead line is based on Voltage Source Converter (VSC) technology. This world-first combination of attributes presents a unique opportunity to study harmonic interaction between weak AC systems and VSC-based HVDC schemes. Relatively few publications exist that focus on AC and DC harmonic interaction and very few refer to VSC HVDC schemes. Because weak AC systems are much more prone to harmonic distortion than strong AC systems, there is a clear motivation for more detailed work in this field. In order to understand the context wherein AC and DC harmonic interaction exists, the fields of AC power system harmonic analysis and resonance, VSC switching theory, HVDC scheme configurations, Pulse Width Modulation (PWM) techniques and frequency domain analysis techniques are discussed. This thesis then presents the concept of Harmonic Amplitude Transfer Ratio (HATR) by a theoretical analysis of AC and DC harmonic interaction due to the fundamental component, as well as harmonic interaction due to scheme characteristic harmonics and is compared to the simulation results obtained from different software solutions. Simulation and modelling techniques for AC and DC harmonic interaction are discussed including AC and DC systems modelling. The theoretical results and simulation results are compared to the results obtained from a real life case study on the CLI HVDC scheme where a harmonic resonance condition occurred. The correlation of these three sets of results confirms the validity of the theories presented and possible mitigation of the case study resonance problems is explored. The results and conclusion highlight a variety of interesting points on harmonic sequence components analysis, VSC zero sequence elimination, AC and DC harmonic interaction due to the fundamental component and the HATR for different PWM methods, AC and DC harmonic interaction due to scheme characteristic harmonics, modelling techniques and mitigation for the resonance conditions experienced in the analysed real life case study. / AFRIKAANSE OPSOMMING: Die implementering van die Caprivi Skakel Tussenverbinder (CLI) hoogspannings- gelykstroom (HSGS) skema in 2010 wat die swak Namibiese and Zambiese Wisselstroom (WS) transmissienetwerke verbind via „n oorhoofse lyn is gebasseer op Spanningsgevoerde-omsetter tegnologie. Hierdie wêreld-eerste kombinasie van eienskappe verskaf „n unieke geleentheid om harmoniese interaksie tussen swak WS stelsels en Spanningsgevoerde-omsetter Hoogspannings GS stelsels te bestudeer. Relatief min publikasies wat fokus op WS en GS harmoniese interaksie bestaan, en baie min verwys na Spanningsgevoerde-omsetter Hoogspannings GS skemas. Omdat swak WS stelsels baie meer geneig is tot harmoniese verwringing as sterk WS stelsels, is daar „n duidelike motivering vir meer gedetaileerde werk in hierdie veld. Om die konteks te verstaan waarin WS en GS harmoniese interaksie bestaan, word die velde van WS kragstelsel harmoniese analise en resonansie, Spanningsgevoerde-omsetter skakelteorie, Hoogspannings GS skema opstellings, Pulswydte Modulasie (PWM) tegnieke, en frekwensiegebied analiese tegnieke bespreek. Hierdie tesis stel dan die konsep van Harmoniese Amplitude Oordragsverhouding voor deur „n teoretiese analise van WS en GS harmoniese interaksie na aanleiding van die fundamentele komponent, asook harmoniese interaksie a.g.v. harmonieke wat die stelsel kenmerk en word vergelyk met die simulasieresultate verkry uit verskilllende sagteware oplossings. Simulasie- en modelleringstegnieke vir WS en GS harmoniese interaksie word bespreek insluitend WS- en GS stelselmodellering. Die teoretiese resultate en simulasieresultate word vergelyk met die resultate wat verkry is uit „n werklike gevallestudie op die CLI HSGS skema waar „n harmoniese resonansie toestand voorgekom het. Die ooreenkomste tussen hierdie drie stelle resultate bevestig die geldigheid van die teorieë soos uiteengeset voor, en die moontlike verbetering van die gevallestudie resonansie probleme word verken. Die resultate en samevatting beklemtoon „n verskeidenheid punte aangaande harmoniese volgorde-komponent analiese, Spanningsgevoerde-omsetter zero-volgorde uitskakeling, WS en GS harmoniese interaksie na aanleiding van die fundamentele komponent en die Harmoniese Amplitude Oordragsverhouding vir verskillende PWM metodes, WS en GS harmoniese interaksie na aanleiding van skema-kenmerkende harmonieke, modelleringstegnieke, asook verbetering van die resonansie toestande soos ervaar in die analise van die werklike gevallestudie.