Shanxi Coal Transportation and Marketing Group Shuimowan Coal Industry Co., Ltd. is located in Shuimowan Village, Madaotou Township, Zuoyun County, Datong City. Shanxi Coal Mine Transportation and Marketing Group Shuimowan Coal Industry Co., Ltd. was reorganized and integrated by the original Datong City Zuoyun County Madoutou Township Shuimowan Coal Industry Co., Ltd. and the original Datong City Zuoyun County Madaotou Township Longwan Coal Industry Co., Ltd. After the integration, it is called: Shanxi Coal Mine Transportation and Marketing Group Shuimowan Coal Industry Co., Ltd. After the integration, the No. 18, 19, 22 and 25 coal seams were approved for mining. The area of the mine field is 5.968km2 and the production capacity is 900,000 tons/year. The production period is 40 years.

The role of the ventilator is to continuously provide a sufficient amount of fresh air to various operating sites underground, to dilute and exhaust all kinds of harmful, toxic and radioactive substances containing gas and dust, to adjust the temperature and humidity of the underground air, and to create a good working environment.

The site ventilation equipment is shown below:

The company's "mine main fan automatic energy-saving control system" has a complete fault diagnosis function, which greatly improves the reliability of the equipment. At the same time, the downhole air volume can be adjusted very easily, which can not only effectively improve the downhole air quality, but also save electric energy, which can save more than 30%-50%.

System configuration and description

High and low voltage distribution system (providing the entire system power supply circuit), frequency conversion control system (stepless adjustment control of the fan), PLC control system, host computer monitoring system, sensor detection system (collecting system pressure, temperature, air volume, gas concentration) etc.). The system block diagram is shown below.

1.Distribution System

Realize power supply to various PLC cabinets, inverter cabinets and sensors.

2. PLC control system

The PLC control system uses the NA400 series PLC. The main fan is one of the four major items in the coal mine, and it is absolutely not allowed to stop. The PLC system uses a hard redundant system, and the core CPU uses two sets, one for each and one for backup. When the current working CPU fails and stops, the standby CPU will automatically take over the control task without human intervention. After the previous faulty CPU is recovered, it continues to operate as a standby CPU, which greatly improves the reliability and stability of the main fan.

Profibus communication is used between the PLC control station and the frequency converter, mainly to complete the frequency converter control and frequency converter running status monitoring tasks.

3.Host computer monitoring system

In the "centralized control" state, users can realize real-time online monitoring of the main fan related machinery and electrical equipment through the monitoring system. Users can directly perform related operations in the graphics window of the host computer to achieve related control requirements. In the "manual" state, the user can only monitor the system status, and the control requirements must be realized by manually operating the keys. The block diagram of the online monitoring system is shown in the figure below.

The host computer uses configuration software to configure the system. The main screens include:

① Overall view of the ventilation system

② System diagram of high and low voltage power supply

③ Dynamic curve of pressure and air volume

Control function

① Switch the fan on and off. Automatic interlock control of dampers and other auxiliary equipment. It realizes the choice of single and double motor operation, with unattended function.

② It has three working methods: local control/local centralized control/remote control. In the local control mode (overhaul mode), each device is operated by the control button of the device itself, which facilitates the overhaul of the device. In the local centralized control mode (manual/automatic, automatically including one-button start of the fan, one-button reverse fan, one-button reverse wind operation, and one-key stop operation), the PLC cabinet completes the coordinated control of the fan and auxiliary equipment. In the remote control mode, the start and stop control of the fan is completed by the upper centralized control computer.

Since the system was put into operation, the equipment has been running well, and the entire system has not had any failures. Received unanimous praise from coal mine leaders and operators.