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Real interpolation method in Automatic Control Systems self-adjustment problem

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Abstract

Practice demonstrates that most of existing methods and techniques of adjustment of the automatic control systems cannot provide the appropriate quality of the systems performing. That is why nowadays main attention is paid to adaptive methods and algorithms. In this paper, the Real Interpolation Method is offered for creation of adaptive Automatic Control Systems. It is based on use of a special case of the Laplace transformation, when the complex variable p = δ + jω comes to real part 5. Due to this approach the number of operations is decreased more than twice in comparison with the frequency domain methods and it considerably simplifies algorithms of self-adjustment of Automatic Control Systems.

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... Based on the above analysis, this study proposes a solution to synthesize and calibrate the regulator using the real interpolation method. This method has a simple procedure and allows for a reduction in computational volume, while preserving the specific features and effects of conveyors on the system [33][34][35]. ...
... One of the methods developed by А.С. Коновалов and И.А.Орурк [33], determining the function has the form (12) with: -the steady-state value and the corresponding maximum of the step response determined based on the required overshoot σ R and the desired static mode of the system. When , the expression (12) takes the form: ...
... The essence of the synthesis method applying the real interpolation method is to convert the synthetic equation (15) to the form with real arguments [33][34][35], choose the distribution rule of interpolated nodes δ i , for example: (16) with η -the number of nodes or establishment the nodes {δ i } n to coincide with the zero points of a Chebyshev polynomial of the first order of degree η (T n (x)) to increase the total accuracy [36]: (17) with: a-The real parameter is used to correct the synthesis error, and {x i } nroots of equation: T n (x) =0, which is determined by the relation [36]: (18) Note that the feedback coefficients k d can be determined from the condition: (19) with, ΔH d -error in the settling mode. Solving equation (15) with two interpolated points (δ 1 , δ 2 ) in the interval δ ∈ [0.1,2], and the interpolation step: Δδ = 0.1, we get the results in Table 1. ...
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The possibility of the embedded automatic-control system construction for a self-adjusted regulator design on the basis of dynamic compensation principle is observed. The description of mathematical and algorithmic apparatus of Control Object identification in a digital form resulted in a design of the regulator. Results of natural experiments are given. An analysis of the regulator robustness properties is carried out.
... The problem body refers to definition of Control Object mathematical model. This part of a problem is solved by two waysanalytical and experimental [1]. In the first case the model is searched on the basis of those laws which present the processes in the Object. ...
... It is the fundamental feature which ensures appreciable reducing of computational burden during organization of numerical information processing procedures -more than 2 times in comparison with frequency method [1,9]. The basic advantages of such approaches are following: • numerical methods developed for the considered class of functions are applicable for action with real functions; • it is possible to find F( ) δ not only with the help of time functions, but also with help of Laplace images, replacing a complex variable s on real δ ; • the mathematical models have graphic representations: that considerably increase obviousness of them; ...
... Second way, which is more interesting and attractive, is based on usage of the information about time dynamic characteristic h(t) of control objects. Following expression defines components of Numerical Characteristic in consideration of (Eq.1) and (Eq.3) [1,9]: ...
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... However, they have complicated calculation procedures and large errors and are not a common technical standard. Therefore, this study will propose and investigate a solution to synthesize and calibrate the regulator using the real interpolation method [24,25]. This method has a simple procedure, allowing direct manipulation of the original model (1) in the real domain and thus reducing the amount of calculation while preserving the specific features and effects of the objects with distributed parameters. ...
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... Особенности двух первых методов в основном достаточно ясны, поэтому остановимся на возможностях ВИМ. Его привлекательность в том, что он позволяет перераспределять погрешность на участках малых и больших значений времени [10]. Условной границей между ними можно считать время, соответствующее величине запаздывания. ...
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