Development Of Terminal Controller For Hydraulic Support In Automated Working Face

This article is an important part of national special international scientific and technological cooperation "development of unattended working face hydraulic support electro-hydraulic control system"(NO.2013DFA70750)and key projects of Shanxi province's major special project "unattended working face hydraulic support automatic tracking machine operation control system.”(NO.2015081013).This subject is proposed for the defects of the domestic electro-hydraulic control system,such as slow information processing,single stent control strategy,fixed communication mode,low automation,and poor environmental adaptability.The hydraulic support is the key equipment in the coal mining automation work surface.Not only provides a safe working space for coal mining operations,but also controls the coordinated operation of relevant equipment and advances the work surface finish coal mining process according to the position of the shearer and the status of the scraper conveyor.At present,the most effective technical way to realize the comprehensive automation control of hydraulic support is the hydraulic support electro-hydraulic control system.However,the domestic electro-hydraulic control system develops later and slower than foreign,basically rely on imports.Foreign products have the disadvantages of high prices and long maintenance intervals,which is detrimental to the development of China's coal industry.In order to narrow the gap between domestic and foreign countries,this paper aims to develop a centralized control system for high-end hydraulic support terminal controller with independent property rights.A terminal controller based on the resource-richhigh-performance single-chip MC9S12XDP512 was designed which together with the explosion-proof computer and the bracket controller,compose a three-level monitoring network for the down hole hydraulic support.In addition to meeting the basic requirements of the mine,the terminal controller integrates four coal cutting process hydraulic support centralized control modes and supports RS485 and CAN bus communication which realizes the full mechanized face hydraulic support automatic follow-up control,remote jogging control,rapid real-time monitoring of support state information,automatic pressure adjustment of hydraulic support,automatic program of support program control,system parameter modification,system online Upgrade,system fault diagnosis,bus communication management,and bus backup switching functions.The main research content of this article is as follows:1?Through the review of documents,participation in international coal mine equipment exhibitions,on-site investigations,the current status of the development of electro-hydraulic control systems at home and abroad has been recognized.Over-the-spot field visits and in-depth communication with technical personnel to understand the automation process of domestic coal production and the technical difficulties existing in the development of fully automated and intelligent coal production at the current stage.In view of the gap between domestic and foreign countries and the current technical difficulties in the domestic electro-hydraulic control system,the functional requirements and technical indicators of the high-end terminal controller were determined and a system model was established.2?Designed the hardware structure of the terminal controller according to the coal mine safety requirements and system technical specifications.Taking the MC9S12XDP512 16-bit microcomputer as the core processor,the intrinsically safe power supply circuit,keyboard circuit,screen display circuit,external memory circuit and reset circuit are designed.Based on the above,two communication modules,RS485 and CAN,have been designed to enhance the communication compatibility of the terminal controller and designed communication management and communication filter circuits.Finally,according to the schematic diagram,the PCB circuit board was drawn and printed into samples.The circuit board was tested through performance test and spark test.The test results show that the terminal controller hardware circuit is reliable and the parameters meet the requirements of intrinsic safety,which can adapt to the harsh environment under the mine.3?Designing a terminal controller software based on CodeWarrior ID E software development platform for the functional requirements of coal mine automation production.The screen display,keyboard scanning,commu nication configuration,communication management,control logic,data anal ysis,FLASH storage management,external RAM storage and management software has been programmed.Achieved a high-end terminal controller th at integrates operation,display,control,monitoring,data storage,logic jud gment,and fault diagnosis.Specifically,it can realize the functions of the bracket jogging control,the bracket group control,the bracket program au tomatic control function,the automatic follow-up control function of a v ariety of coal-cutting methods,the stand column pressure automatic adjus tment function,the system parameter modification function,and the syste m status online monitoring,system fault diagnosis function,system comm unication bus selection and switching function,online upgrade function of bracket controller and terminal controller.Finally,the test of the terminal controller was completed on the test stand of the unattended fully mechanized face hydraulic support electro-hydraulic control system.The test results show that the terminal controller developed in this paper satisfies the design requirements of the high-end support centralized control system.The communication performance is stable and the control strategy is reliable which has reached the domestic advanced technical level.