Research On Variable Frequency Speed Regulation System Of Local Ventilator Based On PLC Control

As the key component of coal mine safety,mine ventilation system plays an important role in coal mine safety.It is one of the main equipments in the system.So research and design of its variable frequency speed regulation system with PLC control have good economic benefits.It not only improves the mechanical and automatic level of coal production,but also saves large electrical energy.Taking a laboratory counter-rotating axial fan as control member,this paper researched and designed its frequency control system combining PLC control technology,frequency control technology and configuration monitoring technology. Firstly,the paper choosed rational system control scheme based on experimental performance curves and control requirements of mine local ventilator.Then control circuit was designed on the scheme.At the same time,hardware like PLC,converters, sensors and so on was distributed and connected.Based on the research of air and methane control algorithm,the PLC control program of system was designed with STEP7-Micro/WIN4.0.After that,according to functional requirements of system,the monitoring system of mine local ventilator was designed with PLC and Kingview.And then the quick-debugging parameters of MM430 converter were set up in system. Some methods of fault diagnosis and exclusion for MM430 converter were generalized. At last,simulation debugging experiments of nmning system were finished.It contained air-control simulation debugging experiment,methane-control simulation debugging experiment and simulation debugging experiment of monitoring system.It was proved that the control system can adjust fan speed to meet wind pressure and rate in heading laneway through simulation debugging experiments in laboratory according to the change of pipe network drag and methane density.Besides,the designed monitoring system can control on-line running of local ventilator.It can also monitor the wind pressure,methane density,fan speed and so on.Meanwhile,the control system had good function of fault warning and treating.