# THEORETICAL ASPECTS AND METHODS OF PARAMETERS IDENTIFICATION OF ELECTRIC TRACTION SYSTEM DEVICES. METHOD OF WEIGHT FUNCTION

## DOI:

https://doi.org/10.15802/stp2014/30763## Keywords:

identification, weight function, electric traction, correlation function, electric locomotive, random process, voltage, current## Abstract

**Purpose.** Development and substantiation of a new method of structural identification of electrical devices of electric traction systems for both DC and AC current. **Methodology.** To solve this problem the following methods are used: the methods and techniques of the linear electrical engineering, in particular, the Laplace operator method; the numerical method for solving the integral equation, which is based on the representation of the Wiener-Hopf linear equations system (this allows forming the solutions of the problem in a mathematical form of the correlation and weight functions); the factorization method, which provides certain partition of the correlation functions of the stochastic processes. **Findings.** It was developed the method of weight function of the electrical devices identification, which can be fully used in the systems of electric traction. As the use example of the developed method it was considered a feeder section of DC electric traction with the single power supply. On this section move two electric locomotives of the type DE 1, they have been identified by the weighting functions. The required currents and voltages of electric locomotives are also formulated in the electric traction network in probabilistic and statistical form, that is, the functions of mathematical expectation and the correlation functions are determined. At this, it is taken into account that the correlation function of the sum of random functions is equal to the sum of the correlation functions of additives, and the correlation function of the integral of a random function is defined as the double integral of the correlation function of the output of a random function. **Originality.** Firstly, originality consists of the adaption of the developed method of structural identification for the devices of electric traction system. Secondly, it lies in the proper development of the new method of weight function. And finally, it lies in the solution of the Wiener-Hopf equation using the correlation method of factorization. **Practical value.** The developed method and the technique that is based on it, allow predicting electric traction loadings of the traction network, as well as the other devices of the traction energy systems and the electric motive power in the different modes of operation and, in particular, during the high-speed train traffic. The method takes into account the load influence (and its mode of operation) of the adjacent feeder zones on the electromagnetic processes in the studied intersubstation area. Thus, it is important that the required voltages and currents are considered as the random functions.

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*Science and Transport Progress*, (5(53), 74–82. https://doi.org/10.15802/stp2014/30763

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