Wyniki 1-3 spośród 3 dla zapytania: authorDesc:"Andrzej GALECKI"

State-space current controller for the four-leg two-level grid-connected converter DOI:10.12915/pe.2014.11.19

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In this paper a state-feedback current controller for four-leg grid-connected converter is presented. Two current control structures are proposed. The elementary one consists of the state regulator and a reference input matrix. The augmented one consists of the elementary structure with additional integral terms. Linear-quadratic optimization method is used to determine the controller coefficients. The developed current controller in the cascaded control structure with an outer PI DC-link voltage controller is used. Simulation results of the proposed control system are presented and discussed at the end of the paper. Streszczenie. W artykule przedstawiono regulator prądu ze sprzężeniem od wektora stanu dla czterogałęziowego prostownika sieciowego. Zaproponowano dwie struktury regulacji prądu. Podstawowa zawiera regulator stanu i macierz wejścia. Rozszerzona składa się ze struktury podstawowej z dodanymi członami całkującymi. Dobór współczynników wzmocnień regulatora przeprowadzono z wykorzystaniem optymalizacji liniowo-kwadratowej. Opracowany regulator prądu współpracuje w kaskadowej strukturze regulacji z nadrzędnym regulatorem napięcia typu PI. W końcowej części artykułu przedstawiono i omówiono wyniki badań symulacyjnych. (Regulator prądu ze sprzężeniem od wektora stanu dla czterogałęziowego dwupoziomowego przekształtnika sieciowego) Keywords: grid-connected converter, state-feedback control, linear-quadratic regulator Słowa kluczowe: przekształtnik sieciowy, sterowanie od zmiennych stanu, regulator liniowo-kwadratowy doi:10.12915/pe.2014.11.19 Introduction Due primarily to an increase of non-linear devices connected to the power system, Engineers are still facing with many of the basic power quality problems such as harmonic pollution and additional power losses in the distribution system. Therefore, a three-phase active rectifier is a promising solution for power quality conditioners [1] and active filters [2]. Furthermore, due to[...]

Control system of the grid-connected converter based on a state current regulator with oscillatory terms DOI:10.15199/48.2015.01.11

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This paper presents a state-feedback current controller with oscillatory terms for three-phase grid-connected PWM converters. Use of the oscillatory terms allows for shaping the sinusoidal input currents of the converter under distorted grid voltage conditions. Linear-quadratic optimization method is used to calculate the current controller gains. In the converter control structure the state current controller and PI DC-link voltage controller are used. Mathematical analysis and simulation results of the proposed control system are presented and discussed. Streszczenie. Wartykule przedstawiono regulator pra˛du ze sprze˛z˙eniem od wektora stanu z rozszerzeniem o człony oscylacyjne opracowany dla trójfazowych przekształtników sieciowych PWM.Wykorzystanie członów oscylacyjnych pozwala na kształtowanie sinusoidalnego pra˛du wejs´ciowego prostownika przy odkształconym napie˛ciu sieci. Współczynniki wzmocnien´ regulatora pra˛du obliczono z wykorzystaniem optymalizacji liniowo-kwadratowej. W strukturze sterowania przekształtnikiem zastosowano opracowany regulator pra˛du oraz regulator PI napie˛cia DC-linku. Przedstawiono analize˛ matematyczna˛ i omówiono wyniki badan´ symulacyjnych. (Układ sterowania przekształtnikiem sieciowym wykorzystuja˛cy regulator stanu ze sprze˛z˙eniem od pra˛dów i sygnałów z członów oscylacyjnych) Keywords: grid-connected converter, linear-quadratic regulator, current controller, harmonic distortion Słowa kluczowe: przekształtnik sieciowy, regulator liniowo-kwadratowy, regulator pra˛du, odkształcenie wyz˙szymi harmonicznymi Introduction Three-phase grid-connected voltage source converters (VSCs) are reliably used in a wide diversity of industrial applications such as adjustable speed drives [1], renewable energy systems [2], [3], power conditioning systems [4] or vehicle-to-grid systems [5]. The conventional control strategies [6] like voltage oriented control (VOC) or direct power control (DPC) are widely used for DC-l[...]

On the similarity and challenges of multiresonant and iterative learning current controllers for grid converters and why the disturbance feedforward matters DOI:10.15199/48.2018.05.07

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It is not uncommon that the iterative learning community members are convinced that their controllers are superior in performance to the multiresonant control schemes. Surprisingly, it also seems to prevail that the designers of multiresonant controllers for grid converters and true sine wave inverters are often not aware that there exists a family of iterative learning control (ILC) laws that is exceptionally simple in implementation, and that the very basic ILC controller can offer similar steady-state errors as the multiresonant controller. Our goal is to make both groups of engineers familiar with both techniques. To begin with, it is necessary to select a common nomenclature. There is no definitive consensus on naming here. Historically, repetitive control was developed for continuous repetitive processes, whereas iterative learning control (ILC) was proposed within the context of batch repetitive processes. After that naming conventions and categorizations only got more and more complicated. The fact is that most ILC techniques can be used successfully for both continuous and batch repetitive processes. Moreover, some authors refer to multiresonant controllers as something that falls outside repetitive control (e.g. [1, 2]), which is rather questionable. We do not feel to be in the position to sort the naming once and for all. However, for the purpose of this paper we propose the following categorization: a repetitive controller is any controller that takes into account (explicitly or implicitly) the repetitiveness of the reference and the disturbance to reduce control errors. Within the repetitive control systems we then distinguish two main techniques: multiresonant control that can be applied only to continuous repetitive processes and iterative learning control that is somewhat more versatile because it can be applied for any type of repetitive control task. We would also like to clarify that ‘repetitive̵[...]

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