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The content of this paper is the national scientific and technological support projects of coal mine safe and efficient mining of coal intelligent combination of the electrical critical technologies \control dispersion. With the high yield efficient face mechanized mining equipment power is increasing, and continuously improve operating voltage 3.3kV working voltage level has been widely used, and put a higher demand on the reliability and safety of electrical equipment. Currently, domestic production of PLC the control core 3.3kV combination switch high reliability, and played a positive role in promoting the 3.3kV electrical control equipment localization aspects, but it can only DC sampling, making the system complex structure, volume large sampling accuracy and real-time poor. Abroad has developed a the combination switch MCU-based monitoring and control system, and greatly improve the performance of the combination switch, but the expensive imported equipment, long lead times, the situation restricting accessories is not easy to buy of 3.3kV high yield efficient face further popularization. Therefore, the study based on the primary structure of 3.3kV combination switch has important practical significance. With the development of computer control technology, there have been many new microcontrollers, computational speed, high reliability, with the PLC incomparable advantages. This article MCU applications to 3.3kV combination switch, designed based on the multi-CPU, the structural the 3.3kV combination switch monitoring and control system. On this system, the lower-level subsystems run in parallel, a clear division of labor. Superiors subsystem microcontroller CPU, complete keyboard input tuning the interactive features of the system status parameter display and communication. Subordinate subsystem DSP CPU, the completion of the data acquisition, data processing, fault discrimination and protection functions. Developed experimental prototype, conduct performance tests on the prototype system, the indicators have reached the design requirements to meet the fully mechanized coal face safe, reliable, efficient production requirements. The main contents are as follows: research status and trends, combined with the combination switch developed fully mechanized coal mining face load control requirements combination switch meet the overall program, determine system technical indicators, and select the appropriate main CPU AC sampling chip analysis of the downhole load and grid leakage failure, the failure of current-and voltage-type fault causes and its electrical characteristics, and the method of protection, provided the basis for the realization of system protection functions. Load since the start based on the pilot of the latching relay circuit, completely overcome; designed as the core of the high-resolution sampling chip CS5463 AC sampling system to improve the real-time measurement and accuracy; selected the XTR105 temperature - Current The temperature detecting circuit of the converter chip design can effectively overcome the platinum resistance error and the error introduced by the line resistance. 4x4 matrix keyboard color LCD screen plus man-machine-channel mode, the design of a friendly human-machine interface, enhanced operability and shorten the discovery and troubleshooting time and improve production efficiency. According to the system requirements, develop the communication parameters in the reliable transmission of real-time monitoring and control system within the upper and lower levels between subsystems and between the superior subsystem with LCD. Modular design method, the preparation of the upper and lower level subsystem applications to facilitate system debugging and development, effectively shortening the program scan cycle, improve the efficiency of the system is running. The 3.3kV combination switch measurement and control system built in the laboratory experiment platform, and software and hardware FBI. Experimental results show that: the measurement and control system is able to accurately, quickly and reliably detect the failure load and grid, protection of sensitive action, reliable, good human-computer interaction, to meet the requirements of coal mine production safety.
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