2-11The article is devoted to assessing the influence of diagnostic parameters for assessing the technical condition of the collector profile of rolling stock traction motors on the value of the mechanical force in the «brush-collector» contact. The results of the experimental studies of the parameters of the collector profile for traction motors EK810Ch of mainline electric locomotives 2ES6 are presented. Four-stage numerical experimental studies were carried out for the following conditions: the first stage - the height differences of the lamellas and harmonics were taken into account; the second stage - the height differences of the lamellas are taken into account without the influence of harmonics (with reduced beating); the third stage - harmonics are taken into account without the influence of differences in the heights of the lamellas (with reduced beating); the fourth stage - harmonics are taken into account without the influence of differences in the heights of the lamellas (with a multiplying factor up to a given beat). Using a mathematical model of brush movement along the collector, a degree of relationship was established between the diagnostic parameters that characterize the state of the traction motor collector profile, with the value of the mechanical force in the «brush - collector» contact. A diagnostic parameter is proposed that characterizes the spread of mechanical force values in the «brush - collector» contact of a traction motor, determined from the ratio of the force of elastic interaction of the brush with the collector and the average value of this force. An analysis of the results of the numerical experiment showed that the contact instability coefficient is largely determined by the value of the standard deviation of the lamella drops and, to a small extent, depends on the values of the harmonic amplitudes. The harmonic composition of the collector profile has practically no effect on the value of the contact instability coefficient at small values of the lamella drops. It is concluded that it is possible to use diagnostic parameters for assessing the state of the traction motor commutator surface to determine possible poor contact between the brush and the commutator. It is proposed to evaluate the quality of repair of collectors of traction motors taking into account the standard deviation of the differences of the lamella.
2-11At this time, an urgent area of development in the field of railway transport is the reduction of operating costs for maintenance and repair of collector traction motors . The analysis of data from the monitoring of new rolling stock shows that one of the elements affecting the reliability during the operation of traction motors is the collector-brush unit. Failures associated with unsatisfactory operation of the collector-brush unit elements reach 30% of the total number for traction motors. At work of traction electric motors there is a continuous process of mechanical, electric and chemical interaction of electric brushes with a collector, leading to deterioration of electric brushes. During the research, the authors proposed a mathematical model to determine the intensity of wear of electric brushes. The paper provides information about developing an approach that allows using the operating data recorded by locomotive on-board parameter monitoring system to determine the service life of traction motor brushes. For elimination of the problem connected with processing of big arrays of parameter values for calculation, in mathematical model of intensity of wear of electric brushes it is offered to divide the received data into intervals with definition of average values and probability of approach for each of them, and also the technique on realization of the offered decision is resulted. The developed approach allows us to eliminate the need for long-term wear tests on traction motors in operation and reduce not only time, but also financial costs. The reliability of the developed method was assessed by comparing the wear values of different types of electric brushes installed on locomotive traction motors in operation with the calculated values.
28-36The article analyzes the test schemes of induction traction motors by the mutual load method using DC generators as load machines and powered by a three-phase AC network with a frequency of 50 Hz. Features of functioning of each of the given schemes of mutual loading are considered. The disadvantages of these schemes are noted, due to the presence of excess equipment or the lack of short-circuit protection in the anchor circuit of the load generator and the complexity of its connection to the DC link. The scheme developed by the authors is proposed, devoid of the noted disadvantages of the known schemes and combining all their advantages, which is the simplest both in the power part and in controlling the process of connecting the armature winding to the DC link of a frequency Converter. A mathematical model of a test system consisting of an induction traction motor, a DC load generator and a two-link static frequency Converter is presented. The mathematical model of this test system is made up of parts corresponding to its individual elements. The presented mathematical model makes it possible to calculate the static and dynamic operating modes of the proposed scheme at the stage of development of an electrical complex for testing induction traction motors. Recommendations on the implementation of developments in the operation of induction traction motors in locomotive repair depots are given. The expediency of implementing the results of work in organizations-developers of test stations for induction traction motors is also noted.
44-54The article is devoted to the problem of improving the DC motor winding armature insulation technical condition diagnosing quality with regard to its frequency properties by forming the equivalent circuit of the electric motor rolling stock armature winding, which allows to determine the frequency numerical values of the parameters,the results of experimental studies of the armature winding oscillatory characteristics as a single-terminal pair are given; and the dependences of the impedance, reactance and active impedance are established. The dependences between equivalent circuits elements numerical values and turn-to-turn location for further formation diagnostic model based on the results.
45-53The article presents the results of experimental researches of process of commutation in traction DC motors. In order to generalize the results of tests of low power engines for electric locomotive’s traction motors, belonging to high power engines, by using the theory of similarity and dimensions we defined the ranges of varying parameters of the operation mode in the experiments. In result of the conducted researches proved the effectiveness of the parameters of laws of distribution of intensity sparking to improve the reliability of the test as low power engines and high power engines.
47-56In this article the generalized results of researches of change of intensity of wear of electrical brushes in the traction motors of electric locomotives. On the basis of the conducted research the author proposes an algorithm to predict the operating life of the brushes, given the parameters of the operation. In order to increase the reliability of the calculation has been developed algorithms, which allow additionally taking into account the effect of the collector’s surface.
52-64The article presents the main requirements for the development of traction motors commutation control digital device and the results of the development and testing of this device on the test bench. Justified the expediency of application of the input highpass filter when the power of the testing traction engine from the thyristor converter. Presented the technique of processing the diagnostic signal from bipolar brushes to filter out noise of different physical nature.
58-66The article presents a universal energy-efficient stand for load testing of asynchronous traction motors, and DC motors. It is proposed to use two options of schemes for testing of traction DC motors with serial excitation and asynchronous motors, and traction motors DC parallel (independent) excitation and asynchronous motors, each of which allows you to implement energy-efficient test method - the method of mutual loading. Given the advantages of the use of the proposed stand. The calculation of the main parameters recorded during the test: currents, voltages and power are invited to perform with the help of mathematical models. Each of the mathematical models takes into account the work of the subjects of the asynchronous traction motors and traction motors DC series or parallel (independent) excitation) by the method of mutual loading: electrical and mechanical link. In conclusion, the article sets out the intended results from the implementation of energy-efficient universal stand for load testing of asynchronous traction motors, and DC motors.
79-85This article describes developed «Collector-brush heat» pc-application », which is aimed to automatically process thermal images, received during thermos-vision of DC machine collector-brush unit. This application allows to calculate the thermal rate and to build collector-brush heating curve. The application is developed in order to apply it in the traction drive diagnostics hardware-software complex.
81-90The article deals with the problem of diagnosing the technical condition of the collector-brush unit of DC motors. The topicality of this problem in the engines operating on the railway transport, which are in the most severe operating conditions, is particularly noted. These studies are aimed at improving the reliability of diagnosing the technical condition of the collector-brush unit through the use of a new method of diagnosing the condition of collector DC motors’ commutation. The proposed method of diagnosis is based on a new principle of processing diagnostic information about the spark pulses under the brushes. The article presents the histograms of the distribution of the pulses' intensity of different sections of the armature winding. The research conducted an experiment using a digital control device that allows to identify and digitize a useful diagnostic signal from multipolar brushes with a high sampling rate and transfer it to a computer. Analysis of the experiment’s results showed that the average value of the pulse’s area increases with increasing the spark’s intensity. Nevertheless, severe sparking at the collector leads to the law of distribution becomes double-modal, and as a result, dramatically increases the standard deviation of the values of the pulses’ areas. Described effect makes misinformation in the diagnosis procedure using the parameters of the laws of distribution of the spark’s intensity. The proposed method of diagnosis allows to eliminate this effect. The copyright for a new method of diagnosing is protected by a patent.