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The analysis of electric energy quality with a required by modern standards accuracy demands applying of digital signals processing. At measurement, one of the main operations is finding signals correlation. Operations performance over digital representations of the signals containing a large points number requires many of computing resources that results in importance of a fast correlation calculation problem. The well-known methods of correlation calculation is applying a range of algorithms: transformation correlation to cyclic convolution, calculation cyclic convolution through FFT and others. These algorithms are well-studied, however their combination make possible additional optimization of algorithms. In paper we offer the method of computing procedure optimization for signals correlation calculation based on operations reduction when performing a sequence two Fourier transformations. Using another way of placing the calculations results we can reduce a data rearranging operations number. Depending on computing architecture, the offered method allows to accelerate calculations to 20 - 25%.

Using the example of operating gas fields in the Western Siberia, the issue of the correct choice of voltage class, considering all the periods of gas fields life cycle, appears. Wrong choice of the voltage class leads to braking development of a gas field. Gas field technological scheme during the each period of the life cycle is considered, the dynamics of the electrical load is estimated. The analysis of existing methods of choosing the voltage class is carried out and their flaws are revealed. Mathematical models of the optimal voltage class calculation and discounted costs calculation are developed using the theory of experiment planning. An algorithm of choosing the optimal voltage is developed and the distribution and supply networks of the external power supply system of the existing gas fields in Western Siberia are investigated. Progressive voltage class for power supply and distribution network is proposed. Conclusions are made.

In article the algorithm of operation of the existing regime automatic equipment of transforming aggregates is considered. Earlier it was read that use of automatic equipment of switching on switch-off of reserve transforming aggregates is an effective remedy of lowering of losses in case of regulation of power of substation depending on tractive loading. Defining factors of assessment of efficiency of automatic equipment are the current and temporal settings, and also restriction of number of switchings in days. The analysis of diagrams of tractive loading showed that there is rather large number of temporal intervals where operation of automatic equipment is ineffective. On the one hand it is connected to the fact that loading is above a point of equality of losses in case of one and two transforming aggregates quite short time, and automatic equipment connects the reserve transforming aggregate already in the course of lowering of loading and disconnects it after a temporal setting. On the other hand - operating restriction of number of switchings of the reserve transforming aggregate in days doesn't allow to gain the considerable economic effect. The decision on use of regime automatic equipment with the existing settings can be the positive if at the same time the estimated effect in the form of abbreviation of losses of the electric power is above cumulative damage from switching of the reserve transforming aggregate. Regime automatic equipment in most cases, it is necessary to consider not as means of obtaining economic effect, and as means of reliability augmentation of operation of semiconductor rectifiers at the peak moments of loading what in turn influences reliability of electrical power supply of pull of trains in general.

The paper discusses the design enterprises for repair in dvizhnogo of railway vehicles, analyzes contemporary experience, are reproduced the main criteria for assessing the quality of design solutions and provides a methodology to optimize them with the use of mathematical modeling.

We consider the ways of increasing the effectiveness of the information-measuring complex of an automated system for monitoring and metering electricity. The possibility of reducing the volume of telemetry traffic in information transmission channels and increasing the energy efficiency of information-measuring equipment is investigated.

Currently, according to regulatory documents, the resistivity of power line wires is assumed to be the same for any permissible load current and the heating temperature of the wires is equal to 20 degrees. This account of resistivity causes significant errors that significantly affect the operating modes of power transmission lines. This article analyzes the influence of outdoor air temperature, load current, solar radiation intensity, wind speed and direction on the heating temperature of overhead power lines, and as a result, on the value of the resistivity of the wires and power and electricity losses in them. The example of the BAM highway shows that even in the conditions of one region, the outdoor air temperature varies, depending on the time of year, within a very wide range. This in turn requires careful consideration of the dependence of the resistivity value of the line wires on the external air temperature. At the same time, it is shown that it is permissible to ignore the intensity of solar radiation, wind speed and direction on the heating temperature of overhead power lines due to the lack of comprehensive information about these factors and their opposite direction. However, this assumption will only be valid for operating currents in the range from zero to double the current value corresponding to the economic density. When calculating power losses, especially in heavily loaded lines, it is necessary to take into account all external temperature influences. Due to the appearance of sensor temperature sensors, it is proposed to use them directly to measure the heating temperature of line wires and then calculate their resistivity.

We propose the concept of the new system for monitoring and electricity metering on the feeders of the D.C. contact network. The system is based on previously designed prototype that has been put into operation, and differs from it in new solutions that allow to achieve greater mobility and simple scalability. We describe the basic technical solutions, the system functions as well as its potential.

Resistive heating of the pantograph head due to the flow of traction current through the conductive elements of the upper node, has an uneven distribution along the frame structure and depends on the location of the contact wire on the insert. The aim of the work is to develop a mathematical model for calculating power losses in the pantograph panhead, allowing to estimate its value, taking into account the zigzag of the contact wire during the movement of electric rolling stock. The subject of the study is the pantograph panhead. The paper gives an example of calculating the frame skid of a pantograph equipped with carbon strips. Experimental studies of the current distribution over the shunts of the panhead depending on the position of the contact wire were carried out in February 2021 in the laboratory "Designs of contact networks, power lines and current collection devices" using a complex for testing current collection devices. The calculation of the heating power of the panhead is determined by the Joule-Lenz law. The results of the calculation showed that the maximum heating power is observed when the contact wire is in the middle of the panhead, while the places of the greatest losses located along its edges are above the places where the shunts are attached. The model makes it possible to obtain a functional dependence of the heating value along the panhead. The obtained results of the skid heating power distribution make it possible to supplement the complex model of the thermal state of the pantograph developed at the Omsk State Transport University with the participation of the authors of the article. The versatility of the developed model makes it possible to investigate various zigzags of the contact wire and evaluate the effect on the distribution of traction current along the panhead, depending on the location of the shunts and their number.

This article is devoted to the investigation of the internal parameters of transformers used for power supply of railway automatic and telemechanic devices. In this paper, the change in the nomogram of the impedance area of a power transformer is considered when changing the parameters of the replacement circuit of this transformer. The possibility of visualizing the change in the parameters of a transformer using the mathematical apparatus of conformal mappings is shown. The nomograms of the input resistance of the single-phase oil transformer are constructed with a change in the value of the insulation resistance and the transient resistance at the junction points. Based on the constructed nomograms, conclusions were drawn on the behavior of the input impedance region of the transformer in various situations.

We consider the concept and architectural aspects of the development of the corporate information sys-tem for monitoring and resources accounting. The relevance of improving automated systems is due to the intensification of the use of modern information technologies in industry. The aim of the work is to select the architecture of the distributed information system for monitoring and resources accounting (hereinafter - the system), which ensures prompt decision-making in the management of technological objects. We consider the current trends in the development of information systems and concepts that provide the requirements established for systems of this class and purpose. The system is based on previously designed prototype that has been put into operation, and differs from it in new solutions that allow to increase mobility and fault tolerance. We describe the basic implemented architectures and the system functionality.

The use of new self-supporting insulated wires and high-temperature wires in the operation of power lines allows increasing the capacity of lines and, as a rule, reducing operational costs. An optimal utilization of the power line load capacity depends on the precise determination of the permissible current loads. The values of permissible currents and steady-state temperature are the main parameters of the line operating mode, affecting the strength and sag of the conductor. The temperature of the wire depends on weather conditions and current load. There are methods for determining the temperature and permissible currents for widely used traditional wires such as AC. They are partially outlined in the EIS (Electrical Installation Standard) and the standard of PJSC FGC UES (Federal Grid Company of Unified Energy System) of 2013. However, there is lack of studies in new types of wires. The paper considers the effect of weather conditions and load on the temperature and real-power losses in insulated and high-temperature wire, and solar radiation is under special consideration. For comparison, we present the results of calculations on traditional AC wires. The research shows that solar radiation, being taken into account, provides an increase of real-power losses of about 2 % with the given values of load and weather conditions. Calculations of permissible current values according to the developed technique for classical AC wires reveal a high coincidence with the values from PJSC FGC UES standard. The relative error is within two percent, and the proposed method is more generalized. It allows simultaneous analysis of both uninsulated and insulated wires. Due to the widespread use of self-supporting insulated wires, power industry experts can use the developed software in the design and operation of modern power lines to optimize capacity.