Conveyor - the main vehicle in the bottom of a coal mine wastewater treatment. He may have one or two actuator 1 on one or both ends of the lattice composition 2 (Fig. 1). Each of his drive can contain from one to two drive units 3. The composition of each drive unit includes kinematic connected asynchronous motor with squirrel cage rotor 4, 5 and the fluid coupling gear 6. The main purpose of coupling is to ensure the smooth start of electric pipeline, the protection of drag chain 7 from the wind when jamming. However, practice has shown that these functions gidromufta does not effectively enough.

Fig. 1: Mine scraper chaine.

Operation of the scraper conveyor differs significantly intensity acceleration traction body, the presence of significant moments of resistance, which vary in a wide range and significantly increased at the beginning of the range of motion drag chain, frequent locking of the chain. During the operation may disable the drive belt in the presence of cargo reshtachnom becoming that leads to a significant increase in the moment of resistance during the subsequent start-up and in some cases - are impeding the implementation start-up drive motors.

Analysis of the structures of promising models of drag conveyors, including the possible use of electromagnetic clutches slide shows indicates the absence of technical solutions that automatically identify the failed launch of the pipeline and eliminate it zashtybovku. Analysis of the methods and devices control high-speed asynchronous motor mode shows that the widely used frequency control method allows us to develop electromagnetic torque not higher than the critical value, it's not enough to automatically loading-outs of gumming reshtachnogo composition pipeline. However, satisfactory performance is different principle of quasi-frequency power induction motor.

Thus, the relevance of the study due to the high probability clogging by cuttings downhole scraper conveyor, launches the fully loaded conveyor, which can lead to a stop the engine and its subsequent failure. Loading-out of gumming conveyor by hand is fraught with considerable complexity.

The purpose and objectives of the study. The purpose of this master's work is to reduce the complexity of manual mine downhole scraper conveyor and an increase in its share at the expense of scientific substantiation of parameters and development of the automatic loading-outs of gummings pipeline through the use of quasi-mode frequency electrical power driving induction motors.

To achieve this goal it is necessary to accomplish the following tasks:

- To analyze the device characteristics and operating coal mine downhole scraper conveyor;

- Review the technical capabilities of known methods for controlling induction motor speeds, including the regime of quasi frequency control;

- To investigate the electromechanical properties of the system "thyristor switch - induction motor" mode quasi frequency control;

- Justify the algorithm controlling the electric conveyor carrying out his automatic loading-outs of gummings;

- To develop structural and basic schemes of a control mean automatic loading-out of gumming the scraper conveyor;

Object of research are electromechanical properties of the asynchronous engine as a part of the electric drive of the scraper conveyor at management in a mode of quasi-frequency power supplies.

Object of research is processes in system "thyristor the switchboard - the asynchronous engine" at quasi frequency management of a high-speed mode of the engine. Methods of researches. Theoretical researches are based on the theory of electric cars, the electric drive, the theory of transients, a method of a spatial vector, the theory of mathematical statistics.[1]

THE BASIC MAINTENANCE OF WORK:

In introduction the theme urgency master works is proved, substantive provisions which define scientific and practical value of results of researches are resulted.

In the first section the mine scraper conveyor as object of research is considered. Thanks to considerable extent and presence of an elastic link a scraper chain, the conveyor is object with the distributed parameters that defines a configuration of its block diagram (fig. 2). Considering that start-up of the asynchronous electric drive differs considerable accelerations, and latchings of a scraper chain high intensity of growth of stretching efforts, driving blocks of the scraper conveyor are equipped fluid coupling, intended for increase of smoothness of start-up of the conveyor and protection of its scraper chain against an impulse at jamming.

Fig. 2: Tendency to application of two-high-speed asynchronous.

Operation practice shows not sufficient functionality of hydromuffs because of not to ability to transfer the high rotating moment on small speeds and high own lag effect. The analysis of the newest workings out in the field of conveyor transport testifies to a steady tendency to application of two-high-speed asynchronous engines. However, the technical decisions, allowing to reveal a stop of the conveyor because of technological overloads and automatically to execute it loading-out of gumming are absent.

In section various ways of management by a high-speed mode of asynchronous engines, including frequency, rheostatic and cascade management are analysed. Basic possibility of the decision of a problem automatic loading-out of gumming the conveyor by use of quasifrequency management by the asynchronous engine is established. [2]

CONCLUSIONS:

Thus, the mode of quasi-frequency power supplies provides the steady lowered frequency of rotation of a rotor and can be used for realization of a step of the lowered speed of a drive at start-up that will allow to raise safety of works in a face. Besides, quasifrequency power supplies provide start-up of the asynchronous engine at the raised moment.

Hence, one of directions of perfection of a drive is refusal of use of hydromuffs applied now and their replacement by semi-conductor switchboards as converters of pressure of a food of the engine.

Remark

When writing this abstract of master's work is not yet completed. Final completion: December 2011. The full text of work and materials on the topic can be obtained from the author or his head after the specified date.

REFERENCES:

1. Маренич К.Н. Асинхронный электропривод горных машин с тиристорными коммутаторами.- Донецк: ДонГТУ, 1997. – С. 22-24 28-29

2. А.с. 1288856 СССР, МКИ Н02М7/00. Устройство для управления трехфазным полупроводниковым коммутатором квазисинусоидального напряжения / И.Т. Сидоренко, К.Н. Маренич, В.В. Люсый (СССР) - №3814792/24-07. Заявл. 22.11.1984. Опубл. 07.02. 1987. Бюл. №5

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