Conditions of coal extractions at Ukrainian mines are the most dangerous comparing to all countries with developed mineral resource industry. Currently at coal mines there is no system for composite condition estimation of material mining equipment, environment and technological processes from the viewpoint of their safety and protection from different types of accidents and their prevention. There should be a single general coal mining computer system for the creation of such prognostic systems. It should gather and analyze all information about coal mine and give recommendations or directive decisions in order to prevent the development of accidents. That’s why I can make a conclusion that this computer network is topical and necessary for Ukrainian coal mines.
Aim of work: the development of single coal mining telecommunication network and research of its characteristics on the base of contemporary electronic equipment with use of modern methods for the development of automated systems, functionally completed intellectual serial component parts that correspond to high modern request of reliability, interference protection, maintainability and interchangeability indicators for exploitation in especially dangerous surroundings.
Object of research: – single coal mining telecommunication network for controlling and coal mine direction which is intended for uninterrupted automatic collection of information about the condition of technological objects ( mining equipment, aerological encirclement, mining massif and other technological links of coal mining manufacture) and also for accumulation, processing and representation of this data.
This computer network is developing on the basis of Abakumov’s coal mine, but this system is modular and it is possible to exploit it for other coal mines.
Main idea of work: is in ensuring of continuous monitoring and analysis of different types of danger, that occur in the process of mining works, with maximal usage of modern technical means, informational technology and microprocessor equipment which are working on the base of created algorithms and special software with indication of the information at the terminal device through the safety server.
For the valuation of advantages of created system I made a comparison of this telecommunication system with similar foreign products. I made a conclusion that foreign systems show only condition of equipment and surrounding at the coal mine. They are not oriented to forecast the state of working safety conditions and equipment safety. They also don’t exercise functions of anti-damage protection of all technological processes at the coal mine.
Formerly transmission and signal processing exercised by inclusion of certain evaluator into automated process, but today intellectual components of automated process need specially developed types of association that operate in the network their own functionality. The appearance of digital interface brought up practically unavoidable transition to local networks. This kind of network which is functioning on the low level of automation system ingenuously next to technological process got the name “fіeldbus” ( industrial network).
Fieldbus is a completely digital bidirectional multipoint communication system which is exploited for connection of the equipment at the objects with systems in attendant position. One of the advantages of Fieldbus system is the ability to support bidirectional connection with a multitude of variable magnitudes. Fieldbus system can exploit three types of interconnection topology: double-pointed, tree-like and multipointed topology. Each system should support general Fieldbus Message Service (FMS) in order to provide realization of user's requests. Currently from 50 types of Fieldbus systems which are represented at the market we can mark out three main types:
Controller Area Network (CAN), Process Fieldbus (PROFIBUS) and Field Instrumentation Protocol (FIP).[1]
Analysis and comparison of switch-control systems’ data in my article “Peculiarity of telecommunication systems at the industrial enterprises” published in the collection “Problems of telecommunications” shows that PROFIBUS and FIP are strong competitors in the industry of equipping technological processes. FIP system realizes new conceptions, for example, division of throughput of a bus by apportionment of time lag with the usage of synchronized clock oscillators. PROFIBUS is based on the ordinary transmission of marker with cyclical informational service for the gratification in real time. Examination of expenditure for adoption shows the possibility of Profibus realization with insignificant additional equipment, because basic data transmission is anisochronous and characterized with symbol-by-symbol conducting. CAN system fits into systems where insignificant waiting time ( to 5 milliseconds) is needed and where large number should be connected to low expenses .
On the basis of analysis of the Fieldbus systems and technologies that exist we can make a conclusion that best technology for construction of general coal mining telecommunication network is Profibus technology. It has high speed of data exchange 500 kbps at a distance 1500 m between units which exceed depth of coal mines’ functioning. Twin-core cable is used as a physical environment for data transmission. One of the important advantages of this technology is Profibus’s orientation on usage in highly explosive conditions. This criteria stands at the first place in the process of control systems’ building of coal mines. In the coal mining conditions this Profibus technology is used like a method that join together sensors, executive settings and machine-specific interface, and gives unlimited quantity of virtual connections through one physical channel. Each virtual channel is a unidirectional logical junction of network output variable with network input variable which is created as series of network batches. Network batches are sent by junction of network output variable to junction of network input variable. Each batch has an update of network output variable value which is decoded and recorded by junction receiver from the address of network input variable.
Examined questions of devices’ interaction and data exchange in the Profibus system, that are invested in my article “Peculiarities of industrial telecommunication systems in the conditions of coal mines”, allow to develop network model and execute modeling of exchange processes for revelation of system’s time delay. This article will be published in the collection “Problems of telecommunications”.
On the basis of my article “Peculiarities of industrial network projecting on the basis of Profibus switch-control system” which was tested at the Ukrainian scientific-technical conference “Computer monitoring and information technologies” organized by Donetsk National Technical University I can make a conclusion that PROFIBUS system realizes all requests to industrial networks and its configuration can be changed due to assigned task. During the period of studying at magistracy I plan to model a coal mining telecommunication network and to analyze the results of this modeling: to define time delay of such network and minimize it, reveal advantages/imperfections of this system and reveal the extent of its effectiveness.