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Guigao Le - One of the best experts on this subject based on the ideXlab platform.
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adaptive integral robust control of Hydraulic Systems with asymptotic tracking
Mechatronics, 2016Co-Authors: Guichao Yang, Guigao LeAbstract:Abstract In this paper, an adaptive integral robust controller is developed for high accuracy motion tracking control of a double-rod Hydraulic actuator. We take unknown constant parameters including the load and Hydraulic parameters, and lumped unmodeled disturbances in inertia load dynamics and pressure dynamics into consideration. A discontinuous projection-based adaptive control law is constructed to handle parametric uncertainties, and an integral of the sign of the extended error based robust feedback term to attenuate unmodeled disturbances. Moreover, the present controller does not require a priori knowledge on the bounds of the lumped disturbances and the gain of the designed robust control law can be tuned itself. The major feature of the proposed full state controller is that it can theoretically guarantee global asymptotic tracking performance with a continuous control input, in the presence of various parametric uncertainties and unmodeled disturbances such as unmodeled dynamics as well as external disturbances via Lyapunov analysis. Comparative experimental results are obtained for motion control of a double-rod Hydraulic actuator and verify the high-performance nature of the proposed control strategy.
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asymptotic output tracking control of electro Hydraulic Systems with unmatched disturbances
Iet Control Theory and Applications, 2016Co-Authors: Guichao Yang, Guigao LeAbstract:In this study, an introduced auxiliary error signal-based robust control method and an adaptive control strategy are synthesised through backstepping method for high precise motion tracking control of double-rod Hydraulic servo Systems. The controller takes the non-linear behaviour in flow, unmatched disturbances in inertia load dynamics, and matched uncertainties in pressure dynamics into consideration. In addition, the developed controller does not require a priori knowledge on the bounds of the lumped disturbances and the gain of the devised robust control law can be tuned itself. As a result, the obtained control strategy can achieve an exact tracking performance for the whole closed-loop Hydraulic system in the presence of matched and unmatched uncertainties simultaneously. Extensive experiments are carried out for the trajectory tracking control of a double-rod Hydraulic servo system and the results reveal the high-performance of the presented controller.
A.h.m. Santos - One of the best experts on this subject based on the ideXlab platform.
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Study of Hydraulic transients in hydropower plants through simulation of nonlinear model of penstock and Hydraulic turbine model
IEEE Transactions on Power Systems, 1999Co-Authors: O.h. Souza, N. Barbieri, A.h.m. SantosAbstract:Study of Hydraulic transients in hydropower plants specifically in Hydraulic turbine units, with penstock, spiral case and draft tube-is necessary due to power and frequency oscillations which normally occur in generator units, mainly during load rejections. In turn, this causes large pressure and subpressure oscillations in turbine Hydraulic Systems and must be evaluated to avoid mechanical failures. In this context, this work analyses discrete Hydraulic Systems with emphasis on Hydraulic parameter analysis. The simulation used was developed based on analog mathematical models of transient phenomenon equations and on a hydro turbine model. The results were obtained by using a nonlinear analog-digital simulation method. Comparisons between results of a theoretical simulation of a literature example using the characteristics method and the results obtained with the present method are presented. Theoretical simulation results obtained from a 360 MW turbine and experimental results are also confronted.
Wojciech Okularczyk - One of the best experts on this subject based on the ideXlab platform.
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Experimental investigations of guide rings made of UHMWPE and PTFE composite in water Hydraulic Systems
Archives of Civil and Mechanical Engineering, 2012Co-Authors: Wojciech OkularczykAbstract:In the present work two materials of guiding elements were tested in water Hydraulic. During investigations of hardness conducted for stuffing box packings in water Hydraulic Systems an analysis of proper selection of piston rod guiding elements has also been carried out (o45f7, Ra = 0.07–0.20 μm, Rm
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Experimental investigations of guide rings made of UHMWPE and PTFE composite in water Hydraulic Systems
Archives of Civil and Mechanical Engineering, 2007Co-Authors: Wojciech OkularczykAbstract:Podczas wykonywania badań trwałościowych uszczelnień dławnicowych w układzie hydrauliki wodnej dobrano skojarzenie, w którym uszczelnienie tłoczyskowe wykonano z UHMWPE, natomiast pierścienie prowadzące z kompozytu PTFE (Kefloy 22). Do badań zastosowano tłoczysko robocze o średnicy ø 45f7 wykonane ze stali chromowo-niklowej AISI 431 ( Cr = 16.7%, Ni = 2.08%), pokrytej płytkami twardego chromu o gr. ≥ 20 µm (elipsoidalność ≤ ¼ f7, liczba mikropęknięć ≥ 5 000/mm^2, Ra = 0.07–0.20 µm, Rm ≤ 2.5 µm). Niektóre z elementów prowadzących, po prawidłowym doborze materiału mogły być używane nadal, mimo zniszczenia uszczelek. Badania prowadzono, utrzymując ciśnienie wody obciążające uszczelki na poziomie p = 8±1 MPa oraz prędkość średnią tłoczyska v ≈ 0,35 m/sek. Temperatura wody, a tym samym temperatura tłoczyska, podczas badań była regulowana w zakresie T _min = 291 K, T_max = 305 K. Otrzymano zmienną wartość współczynnika tarcia pierścieni prowadzących wykonanych z kompozytu PTFE wraz ze zmianą prędkości ruchu tłoczyska. Przy trwałości uszczelnień dochodzącej do 200 km drogi tarcia, pierścienie prowadzące mogły być stosowane kilkakrotnie. Kefloy 22 może być z powodzeniem stosowany na pierścienie prowadzące w Hydraulice wodnej. Oceniono negatywnie stosowanie pierścieni prowadzących wykonanych z PE-UHMW. Zaproponowano kompozyty o składzie pozwalającym na uzyskanie wyników zgodnych z założeniami dotyczącymi ich trwałości. In the present work two materials of guiding elements were tested in water Hydraulic. During investigations of hardness conducted for stuffing box packings in water Hydraulic Systems an analysis of proper selection of piston rod guiding elements has also been carried out (ø45f 7, Ra = 0.07–0.20 µm, Rm ≤ 2.5 µm). Working piston rod has been used for investigations made of chromium-nickel steel AISI 431 ( Cr = 16.7%, Ni = 2.08%). Some of the guiding elements, after proper selection of the material, could be still used, despite damaged seal. The tests have been performed maintaining water pressure on the sealing at a level of p = 8±1 MPa and the average velocity of the piston rod of v ≈ 0.35 m/sec. Water temperature during investigations was regulated within the range of T _min = 291 K and T _max = 305 K. Variable value of friction coefficient has been obtained for the guide rings made of PTFE composite with the change in piston rod velocity. Application of guide rings made of UHMWPE has been estimated negatively.
Guichao Yang - One of the best experts on this subject based on the ideXlab platform.
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adaptive integral robust control of Hydraulic Systems with asymptotic tracking
Mechatronics, 2016Co-Authors: Guichao Yang, Guigao LeAbstract:Abstract In this paper, an adaptive integral robust controller is developed for high accuracy motion tracking control of a double-rod Hydraulic actuator. We take unknown constant parameters including the load and Hydraulic parameters, and lumped unmodeled disturbances in inertia load dynamics and pressure dynamics into consideration. A discontinuous projection-based adaptive control law is constructed to handle parametric uncertainties, and an integral of the sign of the extended error based robust feedback term to attenuate unmodeled disturbances. Moreover, the present controller does not require a priori knowledge on the bounds of the lumped disturbances and the gain of the designed robust control law can be tuned itself. The major feature of the proposed full state controller is that it can theoretically guarantee global asymptotic tracking performance with a continuous control input, in the presence of various parametric uncertainties and unmodeled disturbances such as unmodeled dynamics as well as external disturbances via Lyapunov analysis. Comparative experimental results are obtained for motion control of a double-rod Hydraulic actuator and verify the high-performance nature of the proposed control strategy.
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asymptotic output tracking control of electro Hydraulic Systems with unmatched disturbances
Iet Control Theory and Applications, 2016Co-Authors: Guichao Yang, Guigao LeAbstract:In this study, an introduced auxiliary error signal-based robust control method and an adaptive control strategy are synthesised through backstepping method for high precise motion tracking control of double-rod Hydraulic servo Systems. The controller takes the non-linear behaviour in flow, unmatched disturbances in inertia load dynamics, and matched uncertainties in pressure dynamics into consideration. In addition, the developed controller does not require a priori knowledge on the bounds of the lumped disturbances and the gain of the devised robust control law can be tuned itself. As a result, the obtained control strategy can achieve an exact tracking performance for the whole closed-loop Hydraulic system in the presence of matched and unmatched uncertainties simultaneously. Extensive experiments are carried out for the trajectory tracking control of a double-rod Hydraulic servo system and the results reveal the high-performance of the presented controller.
George T C Chiu - One of the best experts on this subject based on the ideXlab platform.
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non linear adaptive robust control of electro Hydraulic Systems driven by double rod actuators
International Journal of Control, 2001Co-Authors: Bin Yao, George T C ChiuAbstract:This paper studies the high performance robust motion control of electro-Hydraulic servo-Systems driven by double-rod Hydraulic actuators. The dynamics of Hydraulic Systems are highly non-linear and the system may be subjected to non-smooth and discontinuous non-linearities due to directional change of valve opening, friction and valve overlap. Aside from the non-linear nature of Hydraulic dynamics, Hydraulic servoSystems also have large extent of model uncertainties. To address these challenging issues, the recently proposed adaptive robust control (ARC) is applied and a discontinuous projection based ARC controller is constructed. The resulting controller is able to take into account the effect of the parameter variations of the inertia load and the cylinder Hydraulic parameters as well as the uncertain non-linearities such as the uncompensated friction forces and external disturbances. Non-differentiability of the inherent non-linearities associated with Hydraulic dynamics is carefully examined and add...
