Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-02-03T20:53:54Z No. of bitstreams: 1 RaphaellMacielDeSousa_TESE.pdf: 6489062 bytes, checksum: ad0b83d06c244d254f4775bacae900af (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-02-04T19:25:01Z (GMT) No. of bitstreams: 1 RaphaellMacielDeSousa_TESE.pdf: 6489062 bytes, checksum: ad0b83d06c244d254f4775bacae900af (MD5) / Made available in DSpace on 2016-02-04T19:25:01Z (GMT). No. of bitstreams: 1 RaphaellMacielDeSousa_TESE.pdf: 6489062 bytes, checksum: ad0b83d06c244d254f4775bacae900af (MD5) Previous issue date: 2014-11-24 / Os esquemas de controle convencionais aplicados em Filtros Ativos de Pot?ncia Paralelos (FAPPs) utilizam extra??o de ham?nicos, de modo que o desempenho da compensa??o depende da velocidade e precis?o com que os componentes harm?nicos da carga n?o linear s?o identificados. O FAPP pode ser implementado sem o uso de extratores de harm?nicos. Neste caso, a compensa??o dos componentes harm?nicos ? obtida a partir do balan?o de pot?ncia do sistema. O desempenho da compensa??o no caso em que o balan?o de pot?ncia ? utilizado depende da velocidade com que o sistema entra em estado de equil?brio. Neste caso, as correntes de fase s?o indiretamente reguladas por um controlador de dupla sequ?ncia (Double sequence controller - DSC) com dois graus de liberdade, cujo o princ?pio do modelo interno (internal mode principle - IMP) ? utilizado para evitar transforma??es de coordenadas e garantir erro nulo em regime permanente. Adicionalmente o DSC apresenta robustez quando o FAPP opera sob condi??es de desbalanceamento. Al?m disso, o FAPP implementado sem esquemas de detec??o compensam simultaneamente harm?ncos e reativos da carga. Suas capacidades de compensa??o, entretanto, s?o limitadas pela pot?ncia dispon?vel no conversor do FAPP. Tal restri??o pode ser minimizada se o n?vel de pot?ncia reativa compensada for flexibilizado. Um esquema de estima??o que determina as correntes do filtro ? introduzido para conferir flexibilidade na compensa??o de reativos da carga. Resultados experimentais s?o apresentados para demonstrar o desempenho do sistema proposto. / The conventional control schemes applied to Shunt Active Power Filters (SAPF) are Harmonic extractor-based strategies (HEBSs) because their effectiveness depends on how quickly and accurately the harmonic components of the nonlinear loads are identified. The SAPF can be also implemented without the use of the load harmonic extractors. In this case, the harmonic compensating term is obtained from the system active power balance. These systems can be considered as balanced-energy-based schemes (BEBSs) and their performance depends on how fast the system reaches the equilibrium state. In this case, the phase currents of the power grid are indirectly regulated by double sequence controllers with two degrees of freedom, where the internal model principle is employed to avoid reference frame transformation. Additionally the DSC controller presents robustness when the SAPF is operating under unbalanced conditions. Furthermore, SAPF implemented without harmonic detection schemes compensate simultaneously harmonic distortion and reactive power of the load. Their compensation capabilities, however, are limited by the SAPF power converter rating. Such a restriction can be minimized if the level of the reactive power correction is managed. In this work an estimation scheme for determining the filter currents is introduced to manage the compensation of reactive power. Experimental results are shown for demonstrating the performance of the proposed SAPF system.

Made available in DSpace on 2014-12-17T14:55:00Z (GMT). No. of bitstreams: 1 ChristianCA_TESE_1-77.pdf: 2508410 bytes, checksum: e0b647bf37424cb7dc8eeedc2d13d922 (MD5) Previous issue date: 2011-11-04 / Conventional control strategies used in shunt active power filters (SAPF) employs real-time instantaneous harmonic detection schemes which is usually implements with digital filters. This increase the number of current sensors on the filter structure which results in high costs. Furthermore, these detection schemes introduce time delays which can deteriorate the harmonic compensation performance. Differently from the conventional control schemes, this paper proposes a non-standard control strategy which indirectly regulates the phase currents of the power mains. The reference currents of system are generated by the dc-link voltage controller and is based on the active power balance of SAPF system. The reference currents are aligned to the phase angle of the power mains voltage vector which is obtained by using a dq phase locked loop (PLL) system. The current control strategy is implemented by an adaptive pole placement control strategy integrated to a variable structure control scheme (VS-APPC). In the VS-APPC, the internal model principle (IMP) of reference currents is used for achieving the zero steady state tracking error of the power system currents. This forces the phase current of the system mains to be sinusoidal with low harmonics content. Moreover, the current controllers are implemented on the stationary reference frame to avoid transformations to the mains voltage vector reference coordinates. This proposed current control strategy enhance the performance of SAPF with fast transient response and robustness to parametric uncertainties. Experimental results are showing for determining the effectiveness of SAPF proposed control system / As estrat?gias de controle convencionais de filtros ativos de pot?ncia paralelos (SAPF - Shunt Active Power Filters) empregam esquemas de detec??o de harm?nicos em tempo real, usualmente implementados com filtros digitais. Isso pode resultar em altos custos devido o aumento no n?mero de sensores na estrutura do filtro. Al?m disso, esses esquemas de detec??o introduzem atrasos que podem deteriorar o desempenho da compensa??o de harm?nicos. Diferentemente dos esquemas de controle convencionais, este trabalho prop?e uma nova estrat?gia de controle que regula indiretamente as correntes de fase da rede el?trica. As correntes de refer?ncia do sistema s?o geradas pelo controle de tens?o do barramento CC e s?o baseadas no balan?o de pot?ncia ativa do sistema SAPF. As correntes de refer?ncia s?o alinhadas com o ?ngulo de fase do vetor tens?o da rede, que ? obtido usando um PLL (Phase Locked Loop). O controle de corrente ? implementado por uma estrat?gia de controle adaptativo por aloca??o de p?los, integrada com um esquema de controle com estrutura vari?vel (VS-APPC: Variable Structure - Adaptive Pole Placement Control). No VS-APPC, o princ?pio do modelo interno (IMP - Internal Model Principle) de refer?ncia ? usado para eliminar o erro em regime permanente das correntes de fase do sistema. Isso for?a as correntes de fase do sistema a serem senoidais e com baixo teor de harm?nicos. Al?m disso, os controladores de corrente s?o implementados no referencial estacion?rio para evitar transforma??es nas coordenadas de refer?ncia do vetor tens?o da rede. Esta estrat?gia de controle de corrente melhora a performance do SAPF com uma resposta transit?ria r?pida e robusto a incertezas param?tricas. Resultados experimentais s?o apresentados para demonstrar a efic?cia do sistema de controle proposto para o SAPF