Ovsyannikov Mikhail

Faculty electrical engineers

Chair of an electrical supply of the enterprises of cities

Theme of final work:

Specification of calculation burdens imitating method

The supervisor of studies: Pogrebnyak N.N.

    The overall performance of system of electro supply of the industrial enterprise influences its economic parameters, competitiveness of production, an expense of electric energy, etc. Designing of an electric network is based on results of definition of electric loadings of its sites as increase of accuracy of methods of calculation of loadings is pressing question in power. The task of definition of settlement loading has no analytical decision as at the known law of distribution of electric loading it is impossible to determine the law of distribution of temperature of an overheat of a conductor and settlement electric loading. In practice of definition of settlement loadings it is carried out by the engineering modified statistical method. Carried out researches have shown, that the error of operating indications for calculation of electric loadings can exceed admissible value of 10 %. The error is connected with an incorrectness of one of basic formulas of the modified statistical method : if the effective amount of electro receivers is equaled to unit, the factor of settlement loading comes nearer to infinity. For problems which have no the analytical decision, the method of imitating modeling is usually applied. In work the algorithm of an imitating method of definition of settlement loadings is resulted. Lack of this algorithm is that is carried out modeling of ensemble of realizations of the group schedule of active loading on which settlement active loading is determined. Definition of jet loading is conducted according to the engineering method. Such simplification does not answer ideas of an imitating method, leads to decrease in accuracy of calculations.
   It is offered improvements of an imitating method by parallel modeling realizations of group schedules of active and jet loadings of a site of an electric network. The algorithm of the advanced imitating method consists from such steps:
   -imitation of realizations of group schedules of active and jet loadings of a site of an electric network (for each group schedule imitation of individual schedules of active and jet loadings of electro receivers which sum gives group schedules is carried out). Duration of the production schedule is equaled durations of transient of heating of a conductor;
    - calculation of realizations of the group schedule of full loading and temperatures of an overheat of a conductor;
    - definitions of the law of distribution of temperature of an overheat of a conductor and a settlement maximum of temperature of an overheat of a conductor and full settlement loading.
For application of the offered method the made program which allows to define configuration. In addition this program carries out calculations by the engineering modified statistical method and a method of heating dozes. Except for definition of settlement loadings, the imitating method can be used for an estimation of accuracy of engineering methods, modeling of schedules of loadings, an estimation of electromagnetic compatibility of electro receivers. La ck of an imitating method is significant expenses of time which are connected with necessity of imitation of a plenty of realizations of production schedules which make group.