The analysis and design of a cascade proportional-integral (PI) sliding-mode control for a dc-dc boost converter using the locus of a perturbed relay system (LPRS) is presented in this article. The ...implemented system uses a sliding-mode controller for the inner loop and a PI controller for the outer loop to regulate the output voltage. An LPRS representation of the overall system is developed in this article. The latter is used to analyze the frequency and the amplitude of the chattering/ripple (self-excited oscillations) and relates them to the specifications. Besides, the LPRS-method-based analysis and design allows one to find the exact value of the equivalent gain, which is necessary for the analysis of disturbances propagation. Another important contribution is the detailed stability analysis of the two-loop controller through the LPRS method. System stability is analyzed for the two aspects, i.e., the chattering stability of the inner loop and the stability of the full-order two-loop averaged dynamics, through the concept of the equivalent gain. Furthermore, the LPRS is used to operate the converter at a specified switching frequency through defining the controller hysteresis value. Simulations and experimental results are provided to validate the theoretical analysis.
This paper presents a simple and systematic approach to the design of a practical sliding mode voltage controller for buck converters operating in continuous conduction mode. Various aspects of the ...design, including the associated practical problems and the proposed solutions, are detailed. A simple and easy-to-follow design procedure is also described. Experimental results are presented to illustrate the design procedure.
An exact analysis of sliding mode boost converter dynamics based on the locus of a perturbed relay system (LPRS) method is presented in this article. An LPRS representation of the dc-dc boost ...converter based on a full nonlinear model is developed. This is a first known attempt to apply the LPRS concept to an industrial process having a nonlinear model. The frequency and amplitude of the self-excited oscillations (chattering/ripple) are analyzed through the LPRS method. The LPRS is also used to analyze the effect of the propagation of an external disturbance (fluctuations in the source voltage). It is found that the effect of source voltage fluctuations on the system dynamics can be attributed to a combination of the effects of amplitude modulation and input signal propagation. Further, LPRS is used in the design problem of the dc-dc boost converter prototype to determine the required controller hysteresis value which ensures the desired operating switching frequency. Simulation and experimental results are presented to validate and illustrate the theoretical analysis.
In this paper, a fault-tolerant control of a symmetrical six-phase induction generator based on a variable structure strategy is experimentally tested and compared with a classical ...proportional-integral controller. For this, we use a linear feedback sliding mode controller with switched feedback gains in such a way to control the inner current loops of this machine. One main drawback of the classical three-phase induction generator is that it is no longer possible to generate electrical power if only one phase is lost on the stator side. To overcome this issue, we will use a squirrel cage six-phase induction machine that can still operate when at least three phases remain on the stator side. This article proposes to use a variable structure control in order to cope with unbalanced currents and also maintain the generation of power when a loss of the stator's phases occurs. The proposed controller shows its robustness and good regulation performance in healthy and faulty modes. The simulation and experimental tests were carried out with a 24 kW induction machine that represents 1/100 of the electrical power of a real wind turbine.
To improve the control performance and energy efficiency of the hydrostatic transmission (HST) system of wheel loaders, this study proposes a novel variable structure dual-motor hydrostatic ...transmission system, accompanied by a multivariable control strategy based on fuzzy sliding mode control. By constructing a simulation model of the transmission system, the performance of the novel transmission system is verified, and the control effects of common control strategies are compared. The simulation results show that the proposed control strategy and system have good matching and can adapt to disturbances actively. Field experiment results show that the proposed solution can achieve smooth automatic shifting of wheel loaders, while effectively adjusting system pressure, flow, and power. Compared with the traditional hydrodynamic torque converter loader transmission system, its transmission efficiency is effectively increased by 30%, and the efficiency is increased by 8% compared with the traditional hydrostatic transmission system This achievement is of great significance for improving the working efficiency of wheel loaders and reducing energy consumption. The future research focus is to further improve the multivariable control strategy, achieve intelligent operation, and improve the efficiency and reliability of the transmission system.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
DC/DC converters require a controller that ensures high performance under the variations of load and source voltage, ensuring stability and a fast transient response at all operating points. This ...paper provides a detailed analysis of the dynamics of sliding mode boost converter using the locus of a perturbed relay system (LPRS) method. LPRS allows for an exact determination of the amplitude and the frequency of the output voltage oscillations as well as the equivalent gain. Furthermore, it describes the external signal propagation through the system. Analysis of the effect of the source voltage fluctuations on the output voltage waveform is presented in the paper as analysis of exogenous disturbance propagation. The mathematical analysis is verified through simulations and hardware experiments.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
7.
An adaptive VSS control for remotely operated vehicles Dyda, Alexander A.; Oskin, Dmitry A.; Longhi, Sauro ...
International journal of adaptive control and signal processing,
April 2017, 2017-04-00, 20170401, Volume:
31, Issue:
4
Journal Article
We propose a linear matrix inequality (LMI)-based sliding surface design method for integral sliding-mode control of mismatched uncertain systems. The uncertain system under consideration may have ...mismatched norm bounded uncertainties in the state matrix as well as the input matrix. We give a sufficient condition for the existence of a sliding surface guaranteeing asymptotic stability of the full order sliding mode dynamics. We also give an LMI characterization of the sliding surface, together with an integral sliding mode control law guaranteeing the existence of a sliding mode from the initial time. Additionally, we give an LMI condition of sliding surfaces guaranteeing the alpha-stability constraint. Finally, we give a simulation result to show the effectiveness of our method
This study presents variable structure system theory based robust integral controllers for class-D power amplifiers. These amplifiers are highly efficient switching type power amplifiers with ...negligible losses. Sensorless and current feedback based integral controllers with sliding modes are designed to provide robust tracking performance with negligible phase delays and distortions. The methods are capable of providing high-quality outputs by maximising gain and minimising the tracking error and phase shifts. The validity, feasibility and robustness performance of the controllers are investigated through circuit realisations.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
•This paper has presented sliding mode based tracking error minimizing controller for shunt active power filter.•Even though PI controller provides required THD the dc link ripple and size of ...capacitor is higher than the sliding mode controller.•Feedback linearization based sliding mode control ensures desire THD with reduced values of capacitor and it is observe that THD is higher without feedback linearization based sliding mode control for greater chattering.
An improved tracking technique of the reference current waveform in a shunt type active power filter is proposed in this paper using sliding mode control and feedback linearization. Feedback linearization approach helps to reduce the complexity of the controller. Excellent tracking is achieved in both for steady state and dynamic performance. A three-phase four-wire system is considered. The proposed algorithm is simulated first in MATLAB/SIMULINK. An experimental prototype using a dspace1104 based controller is also produced in the laboratory. Results from simulation match well with the corresponding results from experimental prototype confirming the usefulness of the proposed technique.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
