Programme Development And Exprimental Study Of The Single-chip Microcomputer For Automatic Gauge Control System Of Strip Mill

In the production of strip, it is necessary to accurately control the thickness of the plate and strip, which is usually used with automatic gauge control(AGC), to ensure the accuracy of gauge control in strip mill. To develop a set of perfect AGC control device is very important,to realize high precision strip gauge control is great significance. In this paper, based on the AGC control device developed by predecessors, the software design and development of the device is carried out mainly.This system selects PIC24 H series single-chip microcomputer PIC24HJ256GP610 as the core control chip, and design power supply, digital interface, analog interface, encoder interface, serial communication interface according to the actual needs in field. The problems of long time of digital conversion, Darlington tube damage in digital output part, and different types of encoder data acquisition and so on are solved through repeated experiments of durability and full load after inheriting the achievements of former researchers.The main program flow chart is supplemented and improved according to the field application. The main supplement are data recovery by flash simulate EEPROM and introduction of multi-level interrupt mode. Improve loopholes of digital signal, analog signal, encoder signal in acquisition procedures, to ensure the stability and accuracy of the signal. Secondly, combined with the process, complete the main program of the servo valve output control under different system operating conditions and zeroing, press regulation, communication between HMI and computer.Through field investigation and combining rolling theory, make flow chart of pressure closed-loop and position closed-loop mode module.Use incremental PID control algorithm, the closed loop program is implemented by 1ms periodic scanning to ensure the fast and stable control. Drawing flow chart based on requirements of predict control and monitor control.In the end, the experiment circuit is built with a single chip microcomputer controller as the core, the experiment was carried out on the 650 mm mill. The analog quantity, the encoder signal and the partial I/O sampling are completed and compared with the FM458 sampling effect of the original system. At different pressure and time to complete dynamic response experiment of the position closed-loop and pressure closed-loop. After several debugging, achieve the requirements of the user control requirements finally.