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EN
The use of multicellular topology in power quality enhancement can reduce the power loss and also dv/dt of power switches, minimize the electromagnetic interference. However, the failure of flying capacitors can reduce the active filtering efficiency and affect the power quality by injecting currents with wave-form distortion (harmonics, notching, noises etc.) in power distribution grid. Therefore, this study presents a faulttolerant control strategy (FTC) allowing to keep the normal operation conditions of a multicellular converter even under failure mode. The obtained results show that the proposed FTC strategy enhances the power quality of power distribution grid when a fault in flying capacitors occurs.
EN
This paper presents the control design framework for the hybrid synchronization (HS) and parameter identification of the 3-Cell Cellular Neural Network. The cellular neural network (CNN) of this kind has increasing practical importance but due to its strong chaotic behavior and the presence of uncertain parameters make it difficult to design a smooth control framework. Sliding mode control (SMC) is very helpful for this kind of environment where the systems are nonlinear and have uncertain parameters and bounded disturbances. However, conventional SMC offers a dangerous chattering phenomenon, which is not acceptable in this scenario. To get chattering-free control, smooth higher-order SMC formulated on the smooth super twisting algorithm (SSTA) is proposed in this article. The stability of the sliding surface is ensured by the Lyapunov stability theory. The convergence of the error system to zero yields hybrid synchronization and the unknown parameters are computed adaptively. Finally, the results of the proposed control technique are compared with the adaptive integral sliding mode control (AISMC). Numerical simulation results validate the performance of the proposed algorithm.
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
The paper proposes a newrobust fuzzy gain adaptation of the sliding mode (SMC) power control strategy for the wind energy conversion system (WECS), based on a doubly fed induction generator (DFIG), to maximize the power extracted from the wind turbine (WT). The sliding mode controller can deal with any wind speed, ingrained nonlinearities in the system, external disturbances and model uncertainties, yet the chattering phenomenon that characterizes classical SMC can be destructive. This problem is suitably lessened by adopting adaptive fuzzy-SMC. For this proposed approach, the adaptive switching gains are adjusted by a supervisory fuzzy logic system, so the chattering impact is avoided. Moreover, the vector control of the DFIG as well as the presented one have been used to achieve the control of reactive and active power of the WECS to make the wind turbine adaptable to diverse constraints. Several numerical simulations are performed to assess the performance of the proposed control scheme. The results show robustness against parameter variations, excellent response characteristics with a reduced chattering phenomenon as compared with classical SMC.
EN
In this work, we report a new chaotic population biology system with one prey and two predators. Our new chaotic population model is derived by introducing two nonlinear interaction terms between the prey and predator-2 to the Samardzija-Greller population biology system (1988). We show that the new chaotic population biology system has a greater value of Maximal Lyapunov Exponent (MLE) than the Maximal Lyapunov Exponent (MLE) of the Samardzija-Greller population biology system (1988). We carry out a detailed bifurcation analysis of the new chaotic population biology system with one prey and two predators. We also show that the new chaotic population biology model exhibits multistability with coexisting chaotic attractors. Next, we use the integral sliding mode control (ISMC) for the complete synchronization of the new chaotic population biology system with itself, taken as the master and slave chaotic population biology systems. Finally, for practical use of the new chaotic population biology system, we design an electronic circuit design using Multisim (Version 14.0).
EN
In this paper, a sliding mode controller, which can be applied for second-order systems, is designed. Robustness to external disturbances, finite regulation time and a good system’s behaviour are required for a sliding mode controller. In order to achieve the first two of these three goals, a non-linear, time-varying switching curve is introduced. The representative point (state vector) belongs to this line from the very beginning of the control process, which results in elimination of the reaching phase. The stable sliding motion along the switching curve is provided. Natural limitations such as control signal and system’s velocity constraints will be taken into account. In order to satisfy them, the sliding line parameters will be properly selected. However, a good dynamical behaviour of the system has to be provided. In order to achieve that, the integral time absolute error (ITAE) quality index will be introduced and minimised. The simulation example will verify theoretical considerations.
EN
Nowadays, the flexible alternating current transmission systems (FACTS) have emerged and began to play a key role in improving the quality of the grid power. The aim of this work is to design a robust control strategy for the voltage and the flow of reactive power using one of the most popular FACTS devices, namely the STATCOM (static compensator). The proposed strategy consists of a hybrid control (PI control - sliding mode control). This strategy proved its effectiveness in terms of response time and harmonic distortion rate. Furthermore, we investigated the impact of the insertion of a photovoltaic source in the electrical network on the STATCOM operation. Simulation results show that this decentralized source has relieved the grid by its contribution in active power with practically no influence on the performance of the STATCOM, which remains unaffected
PL
Obecnie pojawiły się elastyczne systemy przesyłu prądu przemiennego (FACTS), które zaczęły odgrywać kluczową rolę w poprawie jakości energii sieciowej. Celem pracy jest zaprojektowanie solidnej strategii sterowania napięciem i przepływem mocy biernej za pomocą jednego z najpopularniejszych urządzeń FACTS, czyli STATCOM (kompensator statyczny). Proponowana strategia składa się ze sterowania hybrydowego (regulacja PI – sterowanie ślizgowe). Strategia ta dowiodła swojej skuteczności pod względem czasu odpowiedzi i współczynnika zniekształceń harmonicznych. Ponadto zbadaliśmy wpływ wprowadzenia źródła fotowoltaicznego do sieci elektrycznej na działanie STATCOM. Wyniki symulacji pokazują, że to zdecentralizowane źródło odciążyło sieć dzięki swojemu udziałowi w mocy czynnej, praktycznie bez wpływu na wydajność STATCOM, na co nie ma to wpływu.
8
Content available remote Robust fuzzy sliding mode control implementation for DC motor
EN
This article presents a fuzzy sliding mode control (FSMC) to improve the speed performance of DC motor in direct and opposite directions, where two FSMC approaches are developed and implemented based on the DSpace 1104 board and compared to SMC. Although, the SMC ensures big robustness and excellent disturbance rejection it has a limited application because of the chattering phenomenon that is the main downside of SMC. Firstly, the SMC design speed and current controllers are presented. Secondly, two FSMC approaches are shown. In the first approach, we have a similar control rule as the SMC with the exceptions of the k and ksi of discontinuous control signal parameters which are adapted by a fuzzy inference system. In the second approach, totally we delete the discontinuous control and replace it with an FLC. This article focuses on the design of the FSM speed controller and the estimation of the resistive torque. The numerical and experimental validation results of the FSM second approach have shown a robust mechanism performance with a fast dynamic response, good tracking of the reference speed, zero overshoot compared to SMC (1.22%) and FSM first approach (0.09%), and good rejection Disturbance. Besides, the FSM second approach has the best reduction of chattering phenomenon compared to the FSM first approach and classical SMC.
PL
W tym artykule przedstawiono rozmytą kontrolę trybu ślizgowego (FSMC) w celu poprawy wydajności prędkości silnika prądu stałego w kierunkach bezpośrednich i przeciwnych, w której opracowano i wdrożono dwa podejścia FSMC w oparciu o płytę DSpace 1104 i porównano z SMC. Chociaż SMC zapewnia dużą wytrzymałość i doskonałe tłumienie zakłóceń, ma ograniczone zastosowanie ze względu na zjawisko drgania, które jest główną wadą SMC. W pierwszej kolejności przedstawiono projektowe kontrolery prędkości prądu SMC. Po drugie, pokazano dwa podejścia FSMC. W pierwszym podejściu mamy podobną zasadę sterowania jak SMC, z wyjątkiem parametrów k i ksi nieciągłych parametrów sygnału sterującego, które są dostosowywane przez rozmyty system wnioskowania. W drugim podejściu całkowicie usuwamy nieciagłą kontrolę i zastępujemy ją FLC. W tym artykule skupiono się na konstrukcji regulatora prędkości FSM i estymacji momentu rezystancyjnego. Numeryczne i eksperymentalne wyniki walidacji drugiego podejścia FSM wykazały solidne działanie mechanizmu z szybką odpowiedzia dynamiczną, dobrym śledzeniem prędkości odniesienia, zerowym przeregulowaniem w porównaniu z SMC (1,22%) i pierwszym podejściem FSM (0,09%) oraz dobrą odrzucenie Zakłócenie. Poza tym drugie podejście FSM ma najlepszą redukcję zjawiska drgania w porównaniu z pierwszym podejściem FSM i klasycznym SMC.
EN
This paper presents a comparative study of sliding mode control, hybrid sliding type-1 fuzzy logic and hybrid sliding type-2 fuzzy logic applied on the permanent magnet synchronous machine (PMSM). We used different criteria in this comparison: qualitative, quantitative and robust during the transient and permanent operation of the system. In this article, we present a new sliding mode control strategy applied to the PMSM, this control combines sliding mode and fuzzy logic (type-1 and type-2) to find robust control. The control proposed keeping the part of the equivalent control by sliding mode and will change the part of the switching by a fuzzy controller. Simulation results with a sliding mode control, type-1 fuzzy logic controller (T1FLC) and with an interval type-2 fuzzy logic controller (IT2FLC) of a permanent magnet synchronous machine are presented. The advantage of using interval type-2 fuzzy logic controller is verified.
PL
W artykule przedstawiono badanie porównawcze sterowania ślizgowego, hybrydowej ślizgowej logiki rozmytej typu 1 i hybrydowej ślizgowej logiki rozmytej typu 2 zastosowanej w maszynie synchronicznej z magnesami trwałymi (PMSM). W tym porównaniu zastosowaliśmy różne kryteria: jakościowe, ilościowe i solidne podczas przejściowej i stałej pracy systemu. W tym artykule przedstawiamy nową strategię sterowania trybem ślizgowym zastosowaną do PMSM, ta kontrola łączy tryb ślizgowy i logikę rozmytą (typu-1 i typu-2), aby znaleźć niezawodne sterowanie. Sterowanie zaproponowało zachowanie części sterowania równoważnego w trybie przesuwnym i zmieni część przełączania za pomocą sterownika rozmytego. Przedstawiono wyniki symulacji ze sterowaniem ślizgowym, regulatorem rozmytym typu 1 (T1FLC) oraz interwałowym regulatorem logiki rozmytej typu 2 (IT2FLC) maszyny synchronicznej z magnesami trwałymi. Sprawdzono zaletę stosowania interwałowego sterownika rozmytego typu 2.
EN
When it comes to reducing emissions caused by the generation of electricity, among different renewable energy sources, the solar energy gains prominence, due to its geographical availability, simplicity of implementation, and absence of physical moving parts. However, the performance of photovoltaic systems is dependent on environmental conditions. Depending on temperature and solar irradiation, the photovoltaic (PV) system has an operating point where maximum power can be generated. The techniques that are implemented to find this operating point are the so-called maximum power point tracking (MPPT) algorithms. Since weather conditions are variable in nature, the output voltage of the PV system needs to be regulated to remain equal to the reference. Most of the existing studies focus either on MPPT or on voltage regulation of the PV system. In this paper, the two-stage PV system is implemented so that both MPPT and voltage regulation are achieved simultaneously. Additionally, an improved version of the perturb and observe (P&O) algorithm based on artificial potential fields (APF), called APF-P&O, is presented. According to the results of the simulations carried out in MATLAB/Simulink software, the APF-P&O method is more efficient than the conventional method.
EN
The maglev trains are strongly nonlinear and open-loop unstable systems with external disturbances and parameters uncertainty. In this paper, the Gaussian process method is utilized to get the dynamic parameters, and a backstepping sliding mode controller is proposed for magnetic levitation systems (MLS) of maglev trains. That is, for a MLS of a maglev train, a nonlinear dynamic model with accurate parameters is obtained by the Gaussian process regression method, based on which a novel robust control algorithm is designed. Specifically, the MLS is divided into two sub-systems by a backstepping method. The inter virtual control inputs and the Lyapunov function are constructed in the first sub-system. For the second sub-system, the sliding mode surface is constructed to fulfil the design of the whole controller to asymptotically regulate the airgap to a desired trajectory. The stability of the proposed control method is analyzed by the Lyapunov method. Both simulation and experimental results are included to illustrate the superior performance of the presented method to cope with parameters perturbations and external disturbance.
EN
Solar energy has become one of the most potential alternative energies in the world. To convert solar energy into electricity, a photovoltaic (PV) system can be utilized. However, the fluctuation of sunlight intensity throughout the day greatly affects the generated energy in the PV system. A battery may be beneficial to store the generated energy for later use. A DC–DC converter is commonly exploited to produce a constant output voltage during the battery charging process. A Zeta converter is a DC–DC converter which can be used to produce output values above or below the input voltage without changing the polarity. To deal with the inherent non-linearity and time-varying properties of the converter, in this paper the sliding mode control (SMC) is first analyzed and exploited before being integrated with a proportional-integral (PI) control to regulate the output voltage of the PV system. Disturbances are given in the form of changes in input voltage, reference voltage, and load. Voltage deviation and recovery time to reach a steady-state condition of the output voltage after disturbances are investigated and compared to the results using a proportional-integral-differential (PID) controller. The results show that the proposed control design performs faster than the compared PID control method.
EN
This paper proposes two high-order sliding mode algorithms to achieve highperformance control of induction motor drive. In the first approach, the super-twisting algorithm (STA) is used to reduce the chattering effect and to improve control accuracy. The second approach combines the super-twisting algorithm with a quasi-barrier function technique. While the super-twisting algorithm (STA) aims at the chattering reduction, the Barrier super-twisting algorithm (BSTA) aims to eliminate this phenomenon by providing continuous output control signals. The BSTA is designed to prevent the STA gain from being over-estimated by making these gains to decrease and increase according to system’s uncertainties. Stability and finite-time convergence are guaranteed using Lyapunov’s theory. In addition, the two controlled variables, rotor speed, and rotor flux modulus are estimated based on the second-order sliding mode (SOSM) observer. Finally, simulations are carried out to compare the performance and robustness of two control algorithms without adding the equivalent control. Tests are achieved under external load torque, varying reference speed, and parameter variations.
EN
This paper presents a fault-tolerant control scheme for a 2 DOF helicopter. The 2 DOF helicopter is a higher-order multi-input multi-output system featuring non-linearity, cross-coupling, and unstable behaviour. The impact of sensor, actuator, and component faults on such highly complex systems is enormous. This work employs sliding mode control, which is based on reaching and super-twisting laws, to handle the problem of fault control. Simulation tests are carried out to show the effectiveness of the algorithms. Various performance metrics are analyzed and the results show SMC based on super-twisting law provides better control with less chattering. The stability of the closed-loop system is mathematically assured, in the presence of faults, which is a key contribution of this research.
EN
Propofol infusion in anesthesia administration requires continual adjustment in the manual infusion system to regulate the hypnosis level. Hypnotic level is based on Bispectral Index Monitor (BIS) showing the cortical activity of the brain scaled between 0 to 100. The new challenging aspect of automation in anaesthesia is to estimate the concentration of hypnotic drugs in different compartments of the body including primary, rapid peripheral (muscle), slow peripheral (bones, fat) and effect site (brain) compartment based on Pharmacokinetics (PK) and Pharmacodynamics (PD) model. This paper aimed to regulate the hypnosis level with estimating the Propofol concentrations using a linear observer in feedback control strategy based on Integral Super-Twisting Sliding Mode Controller (ISTSMC). The drug concentration in plasma of the silico patients accurately estimated in nominal transient. The results show that tracking errors between the actual output in form of BIS level and linearized output nearly approaches to zero in the maintenance phase of anesthesia to ensure the controller response on sliding phase with optimum performances by achieving desired hypnotic level 50 on BIS. The robustness of control strategy is further ensured by adding measurement noise of electromagnetic environment of operation theatre distracting signal quality index of the output BIS level.
EN
In this work, we modify the dynamics of 3-D four-wing Li chaotic system (Li et al. 2015) by introducing a feedback controller and obtain a new 4-D hyperchaotic four-wing system with complex properties. We show that the new hyperchaotic four-wing system have three saddle-foci balance points, which are unstable. We carry out a detailed bifurcation analysis for the new hyperchaotic four-wing system and show that the hyperchaotic four-wing system has multistability and coexisting attractors. Using integral sliding mode control, we derive new results for the master-slave synchronization of hyperchaotic four-wing systems. Finally, we design an electronic circuit using MultiSim for real implementation of the new hyperchaotic four-wing system.
17
EN
In this paper, a sliding mode control was applied to a particular underactuated mechanical system, the inertia wheel inverted pendulum. This mechanical system presents strong non-linearities and instabilities in its dynamic modeling. The technique found for control by sliding mode is very easy to implement, it presents a simple control algorithm which can be easily implemented in a real time system. The simulation results obtained are very interesting, they show the efficiency of the proposed approach and that it has good performance in terms of robustness and stability of convergence both for stabilization and for the rejection of external point disturbances to the system.
PL
W tym artykule, sterowanie trybem ślizgowym zostało zastosowane do konkretnego niedostatecznie uruchamianego układu mechanicznego, odwróconego wahadła koła bezwładności. Ten układ mechaniczny wykazuje silne nieliniowości i niestabilności w modelowaniu dynamicznym. Technika sterowania w trybie przesuwnym jest bardzo łatwa do wdrożenia, przedstawia prosty algorytm sterowania, który można łatwo zaimplementować w systemie czasu rzeczywistego. Uzyskane wyniki symulacji są interesujące, pokazują skuteczność proponowanego podejścia oraz dobre wyniki w zakresie odporności i stabilności zbieżności zarówno dla stabilizacji, jak i dla zewnętrznych zakłóceń punktowych do systemu.
18
Content available remote Robust control of power system stabilizer using sliding mode approach
EN
This paper proposes a method of sliding mode control (SMC) approach for excitation control in a single generator-infinite bus power system. Conventional power system stabilizer (C-PSS) design becomes a complicated problem in presence of internal and external disturbances to the excitation of a power system. Improving the stability of the power system has become a priority objective. The aim of this work is to ensure maximum damping of the electromechanical oscillations of the Single Machine Infinity Bus System (SMIB) by the power stabilizers based on the sliding mode control technique. The effectiveness of the proposed approach is demonstrated through computer simulations on two different cases of operating conditions. The performance of the proposed approach is evaluated in terms of damping power system oscillations. The obtained results show the high performance of the proposed controller to improve the stability of the power system compared to the C-PSS and found to be impressive.
PL
W artykule zaproponowano metodę sterowania trybem ślizgowym (SMC) do sterowania wzbudzeniem w pojedynczym generatorowonieskończonym systemie zasilania szyny. Konstrukcja konwencjonalnego stabilizatora systemu elektroenergetycznego (C-PSS) staje się skomplikowanym problemem w obecności wewnętrznych i zewnętrznych zakłóceń wzbudzenia systemu elektroenergetycznego. Poprawa stabilności systemu elektroenergetycznego stała się celem priorytetowym. Celem pracy jest zapewnienie maksymalnego tłumienia oscylacji elektromechanicznych systemu SMIB (Single Machine Infinity Bus System) przez stabilizatory mocy oparte na technice sterowania ślizgowego. Skuteczność proponowanego podejścia demonstrowana jest poprzez symulacje komputerowe w dwóch różnych przypadkach warunków pracy. Skuteczność proponowanego podejścia oceniana jest pod kątem tłumienia oscylacji systemu elektroenergetycznego. Uzyskane wyniki wskazują na wysoką wydajność proponowanego sterownika w celu poprawy stabilności systemu elektroenergetycznego w porównaniu z C-PSS i okazały się imponujące.
EN
In this paper, a design of a simplified sliding mode controller (SMC) for Boost DC-DC converter in continuous conduction mode of operation is presented by defining a simplified formulation for sliding surface. The robustness and stability of the proposed controller are investigated to environment changes. Simulation results show that SMC provides good performance under the climatic changes in term of stability and robustness to irradiance and temperature variations. The proposed converter is a cascaded boost converters under Sliding Mode Control (SMC). The operation of the proposed control of dc–dc converter topology has been verified through simulation using Simulink and its performance has been shown to be satisfactory.
PL
W artykule przedstawiono projekt uproszczonego sterownika trybu ślizgowego (SMC) dla przekształtnika Boost DC-DC w trybie pracy ciągłej przewodzenia poprzez zdefiniowanie uproszczonego sformułowania dla powierzchni ślizgowej. Odporność i stabilność proponowanego kontrolera są badane pod kątem zmian środowiskowych. Wyniki symulacji pokazują, że SMC zapewnia dobrą wydajność przy zmianach klimatycznych pod względem stabilności i odporności na napromienienie i zmiany temperatury. Proponowany konwerter to kaskadowe przetwornice podwyższające w trybie sterowania przesuwnego (SMC). Działanie proponowanego sterowania topologią przekształtnika DC – DC zostało sprawdzone w drodze symulacji z wykorzystaniem Simulink i jego działanie okazało się zadowalające.
20
Content available remote Electric vehicle yaw moment control based on the body sideslip estimation
EN
The direct yaw moment control (DYC) presents an operative solution to improve the stability and road holding of vehicles, in particular electric vehicles equipped with independent motors. The torque control applied to each wheel can improve the handling performance of a vehicle making it safer and faster and in critical driving situations. In this article, a new method proposed for the control of the direct yaw moment based on the sliding mode control. This method uses a new design of switching function to simultaneously track the desired yaw rate and the side slip of the vehicle. The lateral sideslip angle of the vehicle is estimated by using a Kalman filter. The results of the comparative simulations show the effectiveness of the proposed method with the other conventional methods in terms of following the reference yaw rate, the vehicle trajectory and the vehicle skidding in various difficult driving scenarios.
PL
Bezpośrednie sterowanie momentem odchylenia (DYC) stanowi funkcjonalne rozwiązanie poprawiające stabilność i przyczepność pojazdów, w szczególności pojazdów elektrycznych wyposażonych w niezależne silniki. Kontrola momentu obrotowego zastosowana do każdego koła może poprawić właściwości jezdne pojazdu, czyniąc go bezpieczniejszym i szybszym w krytycznych sytuacjach na drodze. W niniejszym artykule zaproponowano nową metodę sterowania bezpośrednim momentem odchylającym w oparciu o sterowanie trybem ślizgowym. Metoda ta wykorzystuje nową konstrukcję funkcji przełączania do jednoczesnego śledzenia pożądanej wartości odchylenia i poślizgu bocznego pojazdu. Kąt bocznego znoszenia pojazdu jest szacowany za pomocą filtra Kalmana. Wyniki symulacji porównawczych pokazują skuteczność proponowanej metody z innymi metodami konwencjonalnymi w zakresie śledzenia referencyjnego kursu zbaczania, toru jazdy i poślizgu pojazdu w różnych trudnych scenariuszach jazdy.
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