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EN
This paper deals with two topics: roll predictions of marine vessels with machine-learning methods and parameter estimation of unknown ocean disturbances when the amplitude, frequency, offset, and phase are difficult to estimate. This paper aims to prevent the risky roll motions of marine vessels exposed to harsh circumstances. First of all, this study demonstrates complex dynamic phenomena by utilising a bifurcation diagram, Lyapunov exponents, and a Poincare section. Without any observers, an adaptive identification applies these four parameters to the globally exponential convergence using linear second-order filters and parameter estimation errors. Then, a backstepping controller is employed to make an exponential convergence of the state variables to zero. Finally, this work presents the prediction of roll motion using reservoir computing (RC). As a result, the RC process shows good performance for chaotic time series prediction in future states. Thus, the poor predictability of Lyapunov exponents may be overcome to a certain extent, with the help of machine learning. Numerical simulations validate the dynamic behaviour and the efficacy of the proposed scheme.
EN
This paper is aimed to describe a wind energy conversion system, including a doubly fed induction generator (DFIG), a bidirectional converter in the rotor circuit the DFIG is able to work as a generator in both sub-synchronous and super-synchronous modes. The topology of a DFIG, stator is connected direct to the grid while the rotor is connected to grid with back to back converters. The wind turbine was controlled using a maximum power point tracking with linear PI regulator. The nonlinear backstepping controller is applied to the rotor side converter (RSC) for the independently control of active and reactive powers taking into consideration the full nonlinear model of the DFIG, we don’t neglecting small stator resistor and using voltage oriented control (VOC). The grid side converter (GSC) is controlled by using the oriented voltage control strategy. Also the DC link voltage control ensures the operation of unity power factor by making the reactive power zero. The obtained results are very satisfactory for this new kind of application.
PL
Niniejsza praca ma na celu opisanie systemu konwersji energii wiatru, w sklad którego wchodzi dwustronnie zasilany generator indukcyjny (DFIG), dwukierunkowy przekształtnik w obwodzie wirnika, który DFIG moze pracować jako generator zarówno w trybie podsynchronicznym, ´ jak i nadsynchronicznym. Topologia DFIG, stojan jest podłaczony bezposrednio do sieci, podczas gdy wirnik jest podłączony do sieci za pomocą konwerterów typu back-to-back. Turbina wiatrowa była sterowana za pomocą sledzenia punktu mocy maksymalnej z liniowym regulatorem PI. Nieliniowy ´ regulator krokowy zastosowano w przekształtniku po stronie wirnika (RSC) w celu niezależnego sterowania mocą czynna i bierna, biorąc pod uwagę pełny nieliniowy model DFIG, nie zaniedbując małego rezystora stojana i stosując sterowanie zorientowane na napięcie (VOC) . Konwerter po stronie sieci (GSC) jest sterowany za pomoca zorientowanej strategii sterowania napięciem. Również regulacja napięcia obwodu posredniego zapewnia ´ pracę z jednostkowym współczynnikiem mocy poprzez zerowanie mocy biernej. Uzyskane wyniki są bardzo zadowalające dla tego nowego rodzaju aplikacji.
3
Content available remote Control of a photovoltaic system by sliding mode based on backstepping
EN
In this article we have studied photovoltaic systems which are non-linear systems. Due to variations in the current-voltage characteristics of PV systems. In fact, we have described the sliding mode method and then we have combined it with the backstepping method. We have applied it to a well-determined PV system. shows that the sliding mode method based on backstepping is more efficient than that of the basic sliding mode.
PL
W tym artykule badaliśmy systemy fotowoltaiczne, które są systemami nieliniowymi. Ze względu na różnice w charakterystyce prądowo-napięciowej systemów fotowoltaicznych. W rzeczywistości opisaliśmy metodę trybu ślizgowego, a następnie połączyliśmy ją z metodą cofania. Zastosowaliśmy to do dobrze określonego systemu fotowoltaicznego. pokazuje, że metoda trybu ślizgowego oparta na krokach wstecznych jest bardziej wydajna niż metoda trybu ślizgowego podstawowego.
PL
W pracy przedstawiono algorytm adaptacyjnego sterowania położeniem ramienia w układzie napędowym z nieliniowym połączeniem sprężystym. Do zaprojektowania algorytmu sterowania użyto metody „całkowania wstecz”. Zaproponowane w algorytmie prawa adaptacji realizują funkcję samostrojenia układu regulacji pozwalając projektantowi na nieznajomość parametrów układu napędowego. Działanie algorytmu zostało sprawdzone symulacyjnie oraz w układzie rzeczywistym.
EN
The paper presents an algorithm of adaptive control of the arm position in the drive with a non-linear elastic joint. The backstepping method was used to design the control algorithm. The laws of adaptation proposed in the algorithm implement the self-tuning function of the control system, and allow to avoid a process of identification parameters of the drive system. The operation of the algorithm has been verified in a simulation and in a real system.
EN
The wind energy conversion systems (WECS) suffer from an intermittent nature of source (wind) and the resulting disparity between power generation and electricity demand. Thus, WECS are required to be operated at maximum power point (MPP). This research paper addresses a sophisticated MPP tracking (MPPT) strategy to ensure optimum (maximum) power out of the WECS despite environmental (wind) variations. This study considers a WECS (fixed pitch, 3KW, variable speed) coupled with a permanent magnet synchronous generator (PMSG) and proposes three sliding mode control (SMC) based MPPT schemes, a conventional first order SMC (FOSMC), an integral back-stepping-based SMC (IBSMC) and a super-twisting reachability-based SMC, for maximizing the power output. However, the efficacy of MPPT/control schemes rely on availability of system parameters especially, uncertain/nonlinear dynamics and aerodynamic terms, which are not commonly accessible in practice. As a remedy, an off-line artificial function-fitting neural network (ANN) based on Levenberg-Marquardt algorithm is employed to enhance the performance and robustness of MPPT/control scheme by effectively imitating the uncertain/nonlinear drift terms in the control input pathways. Furthermore, the speed and missing derivative of a generator shaft are determined using a high-gain observer (HGO). Finally, a comparison is made among the stated strategies subjected to stochastic and deterministic wind speed profiles. Extensive MATLAB/Simulink simulations assess the effectiveness of the suggested approaches.
EN
Photovoltaic (PV) system generates renewable energy from sunlight, which has low efficiency due to the variance in nature of temperature and irradiance in a fast changing environment condition. Different researchers have proposed different maximum power point tracking MPPT techniques to improve the efficiency. However, still there are many open issues. Thus, to address this, a non-linear back-stepping-based higher order sliding mode controller (BHOSMC) is proposed to harvest maximum power from PV system. The PV module and load is interfaced by a non-inverted buck-boost converter (NIBBC). A linear interpolation method is used for voltage generation and Lyapunov stability is used to verify the control system equation. MATLAB/Simulink software is used for testing the proposed controller performance. The experimental result verified that the proposed BHOSMC is robust, accurate and fast tracking, faultless and less chattering as compared to perturb and observe (P&O), back-stepping control (BSC) and back-stepping-based sliding mode control under rapidly varying meteorological condition.
7
EN
In the paper, a control method using backstepping integrated with sliding mode control based on high-gain observer is proposed for an Electro-Hydraulic system (EHS). The observer is dedicated to estimate full-state variables by using output position feedback. In the initial step, the control design formula is constructed via backstepping technique. Following that, the control signal is designed based on sliding mode control (SMC) algorithm, and thus lead to the controller that has the advantages of these two control laws.
EN
Cancer is one of the leading factors of human mortality. The main goal of this article is to present and control a tumor treatment immunity. It can adaptively benefit from the advantages of back-stepping control, the sliding mode control, fuzzy control, and parameter estimation. The cancerous tumor proposed model is a Multi-Input Multi-Output (MIMO) nonlinear fractional-order model. A new back-stepping model based on the sliding mode controller is designed in this paper to deal with the convergence velocity and achieve a robust controller. A new combined Back-Stepping controller with the approach of sliding mode has been designed to solve the convergence velocity challenge, and to face the ordinary back-stepping robustness issue of the controller. Since nonlinear expressions are considered in an indefinite model, a fuzzy controller has been applied to model them. The parameters are estimated using the least-squares method to solve the challenge of uncertainty in parameters. The Back-Stepping model, combined with the sliding mode, has benefited from the advantage of a sliding mode controller, namely, its robustness against uncertainties. The simulation results have demonstrated that the proposed controller has led tumor cells to zero with a higher velocity compared to the integer-order model controller and the adaptive fuzzy conventional Back-Stepping controller.
EN
Robust path following control for underactuated surface ships is an important issue in marine control practice. This paper aims to improve the robustness of the close-loop system with model uncertainties and time-varying disturbances. A practical adaptive backstepping control scheme with a pre-filter is proposed to force a surface vessel to track the predefined path generated by the virtual ship. Based on the Lyapunov stability theorem, this algorithm can guarantee all error signals in the overall system to be uniformly ultimately bounded, and it can be implemented without exact knowledge of the nonlinear damping structure and environmental disturbances. The proposed pre-filter can smooth the commanded heading order and obtain a better performance of the waypoint-based navigation control system. Two simulation cases are drawn to illustrate the validity of the proposed control strategy.
EN
In this work there is presented an analysis of impact of ship model parameters on changes of control quality index in a ship dynamic positioning system designed with the use of a backstepping adaptive controller. Assessment of the impact of ship model parameters was performed on the basis of Pareto-Lorentz curves and ABC method in order to determine sets of the parameters which have either crucial, moderate or low impact on objective function. Simulation investigations were carried out with taking into account integral control quality indices.
PL
W artykule przedstawiono strukturę obserwatora prędkości kątowej wirnika, która jest oparta na rozszerzonym modelu matematycznym maszyny indukcyjnej klatkowej. Funkcje stabilizujące obserwator uzyskano na podstawie metody backstepping. Ponadto zastosowano ślizgowe funkcje przełączające. Przedstawiono badania eksperymentalne.
EN
The speed observer structure of induction machine in which is based on extended induction machine model is presented in this paper. Stabilizing functions are obtained by using the backstepping approach. Furthermore the sliding mode control law is used. The experimental results are presented.
EN
The article discusses the issue of designing a dynamic ship positioning system making use of the adaptive vectorial backstepping method and RBF type artificial neural networks. In the article, the backstepping controller is used to determine control laws and neural network weight adaptation laws. The artificial neural network is applied at each time instant to approximate nonlinear functions containing parametric uncertainties. The proposed control system does not require precise knowledge of the model of ship dynamics and external disturbances, it also eliminates the problem of analytical determination of the regression matrix when designing the control law with the aid of the adaptive backstepping procedure.
EN
In this paper, we propose a robust nonlinear control design concept based on a coefficient diagram method and backstepping control, combined with a nonlinear observer for the magnetic levitation system to achieve precise position control in the existence of external disturbance, parameters mismatch with considerable variations and sensor noise in the case, where the full system states are supposed to be unavailable. The observer converges exponentially and leads to good estimate as well as a good track of the steel ball position with the reference trajectory. A simulation results are provided to show the excellent performance of the designed controller.
EN
The main objective of this paper is to present the performance analysis of the oriented flux control of an induction motor associated with a matrix converter. A polynomial technique of RST type is used for speed control. As for the control of internal current loops, the technique used is based on the nonlinear approach. Overall, the proposed feedback law is asymptotically stable, which is shown in the context of the Lyapunov theory. The design of the control laws by the backstepping technique has been detailed while taking account of the non-linearities in the design phase of the control system. The objective is to obtain a good transient response and a good capacity of rejection of charge disturbance. The induction motor incorporating the proposed control techniques (RST-Backstepping) has been successfully implemented in numerical simulation using Matlab/Simulink under different operating conditions where the static and dynamic responses of the system are evaluated. It can be seen that the proposed control technique provides good speed monitoring performance. For internal loops, overall stability is ensured and the proposed approach presents good robustness to the uncertainties of the system parameters.
PL
W artykule zaprezentowano analizę właściwości sterowania silnikiem indukcyjnym za pośrednictwem przetwornika macierzowego. Zastosowano wielomianową technikę RST do sterowania prędkością. Do sterowania pętlą prądową zastosowano metodę nieliniową. Zaproponowane sprzężenie zwrotne jest asymtotycznie stabilne w konteksście teorii Lapunova. Numeryczne symulacje wykazały skuteczność zaproponowanej metody.
EN
Backstepping is a method designed to control nonlinear systems. Formulated for the first time and described by Petar Kokotovic around 1990. The main purpose of backstepping is stabilisation of each subsystem’s structure; the function needs to be of an adequate class. The present task consists in minimising the vehicle body displacement from the position of equilibrium after it has been knocked out of it with the force exerted on the wheel, which has the purpose of simulating the wheel encountering an obstacle. The model depicts ¼ of the vehicle suspension with a conical spring or classical spring, and the damper with magnetorheological fluid which modifies damping of the suspension. The Mathcad programme facilitated the calculations, the model was designed using the Matlab – Simulink environment. Simulations were carried out on the model with the linear characteristics of a spring, as well as on the model with the implemented nonlinear spring. All the investigated cases were accompanied by the control tests that comprised building the model without control, i.e. with the constant value of damping
EN
The most problem of direct torque control are high torque ripple and Settling time to overcome this problem an efficiency Backstopping speed controller are proposed. This paper makes a comparison of the effectiveness of three PI speed controller based direct torque control, the first one is the classical PI speed controller (CL-PISC), the second are no Adaptive Backstepping controller (NABACKSC), and the third type are adaptive fuzzy PI controller (AF-PISC). The parameters of adaptive fuzzy PI are dynamically adjusted with the assistance of fuzzy logic controller. The non-Adaptive Backstopping controller is designed based on the Lyapunov stability theorem. The direct torque control is very adapted for electric propulsion systems; we apply this new strategy for an 15 Kw induction motor. The proposed PI controllers are simulated in MATLAB SIMULINK environment. The simulation results confirmed that the NA-BACKSC, present robust and the best dynamic behavior on direct torque control compared to AF-PISC and CL-PISC.
PL
W praktyce, dynamika statku jak również zakłóceń środowiskowych oddziałujących na kadłub nie jest dokładnie znana, co wynika ze zmieniających się warunków eksploatacyjnych jednostki i stanów morza. W artykule przedstawiono zagadnienie projektowania regulatora pozycji i kursu statku z zastosowaniem algorytmu całkowania wstecz (ang. backstepping). W pracy rozważono układ dynamicznego pozycjonowania statku z niepewnościami parametrycznymi modelu oraz pomiarowymi. Niepewności parametryczne związane są z hydrodynamicznymi siłami tłumiącymi, natomiast pomiarowe z niemierzalną predkością statku. Porównano działanie układu adaptacyjnego zakładając występowanie niepewności oraz nieadaptacyjnego przy założeniu dokładnej znajomości modelu statku. Wyniki badań symulacyjnych wskazują zbliżone wyniki w obu rozpatrywanych przypadkach.
EN
In commercial Dynamic Positioning systems is still used PID control, despite a significant increase in the level of automation. To improve the quality of the positioning of the vessel may allow the use of more effective methods and algorithms, providing advanced nonlinear control techniques. The problem of synthesis a dynamic positioning system for surface vessel with uncertainties was considered in this paper. In practice, both the dynamics of a dynamically positioned vessel as well as environmental disturbances affecting on a hull are not precisely known, as a result of the changing operating conditions and the sea states. The article presents the problem of position and heading controller design by vectorial adaptive backstepping methods. The dynamic positioning vessel with parametric model uncertainties associated with hydrodynamic forces damping, low-speed ship and in the presence of waves disturbances was used. Comparison of the system with uncertainties and assuming precise knowledge of ship model was carried out. Finally simulations results demonstrate similar results in both cases. Adaptive controller follows desired trajectory with small neighborhood. All signals in the closed-loop DP control system are bounded.
PL
W komercyjnych systemach dynamicznego pozycjonowania statku, pomimo znacznego wzrostu poziomu automatyzacji, wykorzystywane jest nadal sterowanie typu PID. Poprawę jakości procesu pozycjonowania może umożliwić wykorzystanie bardziej efektywnych algorytmów, oferujących zaawansowane nieliniowe techniki sterowania. W artykule przedstawiono zagadnienie projektowania regulatora pozycji i kursu dla układu dynamicznego pozycjonowania statku, z zastosowaniem rekurencyjnej wektorowej metody backstepping. Wielowymiarowy regulator backstepping został zastosowany do stabilizacji pozycji i kursu na wartościach zadanych, w obecności zakłóceń falowych. Do estymacji prędkości statku i filtracji zakłóceń zastosowano nieliniowy obserwator pasywny. Wyniki symulacji porównano z nieliniowym regulatorem PID.
EN
In commercial Dynamic Positioning systems is still used PID control, despite a significant increase in the level of automation. To improve the quality of the positioning of the vessel may allow the use of more effective methods and algorithms, providing advanced nonlinear control techniques.The problem of synthesis a dynamic positioning system for low frequency model of surface vessel was considered in this paper. The recursive vectorial backstepping control design was used to keep a fixed position and heading in presence of wave disturbances. The passive observer was introduced to smooth the measurements and to estimate the velocities needed for the control algorithm. The simulation results were compared with PID controller.
19
Content available remote Sterowanie adaptacyjne silnikiem PMSM z dowolnym rozkładem strumienia
PL
W artykule przedstawiono algorytm sterowania adaptacyjnego silnikiem z magnesami trwałymi z dowolnym rozkładem strumienia. Do syntezy algorytmu zastosowano zmodyfikowaną metodę adaptacyjnego wstecznego całkowania. Zadane wartości prądów w osiach d i q wyznaczane są zgodnie z zasadą maksymalnej wartości momentu na amper - MTPA. Poprawność algorytmu ilustrują wyniki uzyskane na drodze symulacji komputerowej.
EN
This paper presents an algorithm for adaptive control of PMSM motor with any distribution of the flux. The modified adaptive backstepping method was used for synthesis of control algorithm. The dq reference currents are determined by the principle of maximum torque per ampere – MTPA. Simulation results were demonstrated for the drive system under chosen operation conditions.
PL
W artykule przedstawiono działanie nieliniowego algorytmu sterowania backstepping użytego do stabilizacji wahadła odwróconego IWP (Inertia Wheel Pendulum). Analizowanym obiektem jest konstrukcja umocowana na dwóch kołach i posiadająca silnik napędzający koło zamachowe. To czyni z niej nieliniowy układ o dwóch stopniach swobody (kąt odchylenia od pionu i kąt obrotu koła) i jednym wymuszeniu (moment siły na wale silnika). Jako punkt pracy obrano niestabilną pozycję pionową. W oparciu o teorię stabilności Lapunowa, analitycznie wyznaczono prawo sterowania. Dla porównania wyznaczono również sterowanie liniowo-kwadratowe LQR (Linear Quadratic Regulator). Wykonano testy symulacyjne obu algorytmów wykazując, że w wielu sytuacjach sterowanie backstepping pozwala uzyskać lepsze rezultaty niż sterowanie LQR.
EN
This article describes the non-linear backstepping control algorithm used to stabilize the inverted pendulum IWP (Inertia Wheel Pendulum). The analysed object is a construction mounted on two wheels with an electric motor accelerating the flywheel. This is the non-linear system with two degrees of freedom (the angle of inclination and rotation of the wheel) and one actuator (torque on the motor shaft). The vertical position is the unstable operating point. The Lyapunov stability theory allowed to formulate the control law analyticity. The result is compared with the linear-quadratic control LQR (Linear Quadratic Regulator). The simulation tests showed differences of both algorithms and benefits of using backstepping.
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