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The amount of electro receiver is increased in our time, which has nonlinear voltampernaja characteristic. It results in worsening of electromagnetic compatibility (EMS), that leads the way the unjustified increase of losses of electric power, death electrical equipment, false working of control system. Therefore considerable money facilities are annually lost in Ukraine. Charges on overcoming of these problems are considerably higher, than charges on their prevention.
Providing of EMS is one of the basic requirements, which is produced to the system of power supply. Understating of estimations of EMS leads harm from the additional losses of electric power, decline of term of service of electrical equipment, deterioration of quality of products, and overstating - to the unjustified increase of capital investments on a power supply.
Practical actuality of this master's degree work is a task of receipt of objective estimation of EMS both on the stage of planning and during exploitation of electric networks.
Practice of application GOST 13109-97 on the norms of quality of electric power in the systems of power supply exposed basic scientific contradiction: the existent indexes of quality of tension are oriented to invariable in time electric, periodically changing violations of EMS, while in the operating electric networks of hindrance have casual character. Therefore becomes incomprehensible, with what ordinate of hindrance to compare the normative value of index of quality of tension and how to use those descriptions of periodic hindrance, which lose sense for a periodic hindrance. This is explaining the necessity of application of probabilistic methods for the analysis of processes in the systems of power supply. The static design of processes of x(t) in the systems of power supply allows to decide nonlinear tasks which do not have an analytical decision. In our case for determination of parameters of EMS it is necessary with high exactness to imitate descriptions of entrance hindrance in which beforehand a normal function of distributing and model correlation function are known.
Scientific actuality of work is conditioned absence of analytical decision of tasks of estimation of EMS for casual hindrances. In this work for a decision the method of elementary processes is used.
Purpose of work – research of authenticity of generation of pseudo-random numbers and casual functions of time by the method of elementary processes. Basic idea of work – use of imitation of casual process, which replaces the real experiment.
The executed researches showed that this in theory correct method did not give high exactness during computer realization. It is explained that sequence casual ordinates differs from white noise which can not be reproduced. The method of elementary processes is offered in this connection.
For this purpose it is necessary to decide the followings tasks:
- random numbers are imitated with the exponential distributing, and the rightness of imitation is checked up;
- exactness of reproducing of elementary process is checked up with an exponential correlation function;
- imitated sums of elementary processes, a correlation function and normal distribution is checked up;
- quadratic cumulative averaging of sum of processes is carried out at different times of correlation.
In engineering practice the simplest estimation was used on a size and duration controlled parameter, which was formulated as principle of a maximum of the middle loading. For example, as settlement of the electric loading on heating half-hourly a maximum of the middle loading is used. Afterwards this principle was widespread on the indexes of quality of tension. In this case in place of inertia a cumulative link is used, which in the rate of the real time executes averaging of reaction on an interval . Cumulative process:
has a that dimension, what hindrance. Transformation approximately estimates energy of reaction in times of kumulyacii only at small distinctions in the effective and middle values of reaction.
A cumulative link, executing transformation, has transitional and powerful functions, and also ACHF and phase-frequency functions.
We will use the resulted cumulative process:
the dimension of ordinates of which it is coincided with the dimension of ordinates of reaction.
Construction of dependence of cumulative maxima and minima from parameter of correlation function will be a work end result. At a positive end verification of possibility of imitation of eksponencial'no-kosinusoidal'noy of correlation function will be executed:
Practical value - it is possible to define the index of EMS from GOST on the certain stage of planning.