| Coal mine substation is the transmission hub between the safety monitoring module under the mine and the safety monitoring Centre above the mine. It takes charge of data collection and communication between the safety monitoring module and the safety monitoring Centre. It's determined by data collection substation that weather the coal mine safety monitoring can work efficiently. And the substation plays an important role in the coal mine safety monitoring.This thesis originates from the project "The coal mine safety monitoring and management system". The system will not only develop and perfect some key equipment, such as the explosion-proof industrial Ethernet Switch, underground intelligent control substation, and so on, but also perfect the integrated information management system. So as to lead the system to realize the function of intelligent aided decision-making and automation control.In this paper, we design a Flameproof and Intrinsic safety power supply, its output voltage is 18V and it has a total of six output channels for the use of substation and all kinds of transducer.As an important part of the coal mine safety supervision and management system, a network substation based on ARM microprocessor is designed in thesis which can be used underground. This substation regards the real-time operating systemμC/OS-Ⅱas operating platform, realizes the communication with ground computer via embedded UDP protocol. This substation removes the disaccords among different underground substations.In the hardware, according to the "General technical requirements of coal mine safety supervision", the thesis completes software and hardware designs of the substation. And the Ethernet connecting is realized by RTL8019AS in hardware. ARM microprocessor LPC2214 which has 16KB on-chip Static RAM, 256KB on-chip high speed Flash Program Memory is used as the master control chip in the substation. In addition, the LPC2214 microcontroller has 8-channel 10-bit A/D converter with conversion time as low as 2.44μs, multiple serial interfaces and up to 76 general purpose I/O pins (with external memory). It goes without saying that it is particularly suitable for industrial control. With a wide range of serial communications interfaces, it is also very well suited for communication gateways as well as other general-purpose applications. The substation has the man-machine conversation interface of LED Displaying and infrared remote Key-press. It can communicate with the ground computer via UDP protocol. A more complex algorithm is realized by the ground computer.In the software, the embedded operating systemμC/OS-Ⅱis transplanted to the LPC2214 base on which the TCP/IP protocol stack is realized. Data format of exchange is established. And UDP protocol is used to communication between the underground substation and ground computer. At last the thesis introduces the thinking in program of several program modules in tail, such as the module of LED displaying, the pulse signal with a defined frequency counting and data storing, etc. At the same time, the solution of some problems in the practical programming and method of debugging are put forward.The substation has eight A/D data collecting, eight digital inputs, eight digital outputs, man-machine conversation interface, RS485 interface, and internet communication interface. The noticeable point is that all parameters collected can be protected well when they are in the state of power breakdown. The substation has not only realized the functions of data collecting, key-press processing, LED displaying, but also realized bidirectional communicate with ground computer.
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