Functional application of unattended bucket wheel stacker reclaimer system

1.Application Background

With the progress of technology, coal mines, terminals, thermal power plants, thermal power plants and other places where coal needs to be stored and turned around are becoming more and more automated, and the manual operation method can no longer meet the needs of the growing socio-economic development. Influenced by factors such as globalization of international trade, large fluctuations in raw material prices, and rising labor costs, reducing production costs to improve social and economic benefits has become an important factor in the development and growth of enterprises. The bucket wheel stacker reclaimer is a continuous and efficient working production machine. In order to adapt to highly automated production, reduce labor intensity and cost, and stabilize work efficiency, the automatic control of the bucket wheel stacker reclaimer has been spawned, while establishing the basis for an intelligent fuel control system.

2.Control mode analysis

(1)Manual mode: All the operating mechanisms of the bucket wheel machine need to be operated manually, which requires frequent operation, long equipment running time, high loss, long time concentration of personnel, long time, high labor intensity, difficulty in controlling the stability of coal flow, and leads to lower work efficiency.

(2)Automatic mode: constant-flow pickup improves pickup efficiency, reduces equipment maintenance costs, allows remote centralized control of multiple bucket wheel machines, and increases various safety protection functions.

3.System Introduction

Through the automatic transformation of the bucket wheel machine, the data collection modules of coal pile modeling, material height detection, coal flow detection, anti-collision detection, precise positioning and visualization monitoring are added, and after data calculation, analysis and judgment, the fully automatic control of the bucket wheel pile picker on coal pile picking, tracing, flow and operation mode is realized, and the unmanned and intelligent automatic control of the bucket wheel machine is realized. It greatly improves the operation efficiency of bucket wheel machine, significantly reduces the energy consumption of material delivery unit, reduces the labor intensity of driver and improves the operation environment, significantly reduces the number of staffing, with significant economic and social benefits, and also lays the foundation for the construction of intelligent fuel and intelligent power plant.

4.System Diagram

5.System Functions

(1)Remote Monitoring Center：

The bucket wheel fully automatic system centralized control platform performs intelligent analysis and calculation of information such as stack position, instantaneous flow, bucket wheel position and status, realizing remote one-touch positioning and operation start-stop control of the bucket wheel, with no intervention in the whole process. It realizes precise and accurate control of constant flow and supports mixing and matching of multiple bucket wheelers according to the set ratio.

Remote network heartbeat detection mechanism is established in the form of server background software service, so that once the communication signal is interrupted, the bucket wheel stacker feeder will be automatically shut down; the monitoring screen is centrally displayed inside the coal conveying control to facilitate the control personnel to centrally display the video monitoring screen of each system in the coal conveying control room. There is an emergency stop button on the centralized control console, in case of emergency, the coal control remote can control the power supply of the bucket wheel stack feeder to power off.

The control of the bucket wheel stacker and reclaimer supports three modes: remote fully automatic operation mode, remote manual operation mode, and centralized operation in the driver's room.

The 3D model of the stockpile is dynamically updated to meet the requirements of automated operations. The operator can look up the coordinate data (height and position data) of the position at any point on the 3D graphic. When the bucket wheel stacker reclaimer is working, the current operating status can be observed through multiple angles. The operator can pan, rotate and zoom the 3D model in the system at will with the mouse

(2)PLC control system：

The bucket wheel stacker and extractor is added to the bucket wheel fully automatic control cabinet, which contains PLC module, communication module, network switch, low-voltage electrical components, etc.

Electrical and control should meet the requirements of coordination, normal and safe operation of each institution, and provide all kinds of necessary protection to complete the safe control of each load of the whole machine.

(3)Acquisition sensing device：

Accurate positioning: According to different industrial sites, industrial-grade satellite positioning technology, high-precision coding positioning, non-contact slew/pitch angle detection devices, etc. can be used, and can be supplemented with address code position calibration devices based on RFID technology to achieve redundant configuration of the positioning system, real-time detection of bucket wheel loader and cantilever pitch/slew angle, and the accuracy can reach centimeter level.

Instantaneous coal flow and material height detection: add laser scanning device on the cantilever belt of bucket wheel stacker reclaimer to realize real-time coal flow flow detection during the process of reclaiming material, as a constant flow control adjustment parameter for coal reclaiming. Add laser scanning device on the tail belt of bucket wheel stacker reclaimer to realize real-time coal flow detection during stacking/shunting process, as the automatic shunting control adjustment parameter. Installation of a radar level detection device on the head of the cantilever of the bucket wheel stacker and reclaimer to detect the height of the coal pallets and to participate in the height control during fully automatic stacking

Laser scanner: The laser scanning device installed on the left and right sides of the cantilever head or the laser scanning device installed on the upper part of the closed coal yard scans the working surface of the pallets in real time, and the real-time measurement server completes the 3D real-time modeling of the pallets to obtain a high-precision 3D model of the pallets, which is used as the basic data for fully automatic control.

Anti-collision monitoring: Ultrasonic sensors are installed on both sides of the front and rear of the bucket wheel stacker reclaimer walking track, which are used to achieve the measurement of the distance between the front and rear of the stacker reclaimer walking process to prevent the collision of personnel or equipment, and the ultrasonic sensor signal is connected to the PLC control system to achieve the overall chain protection of the stacker reclaimer. In the bucket wheel stacker reclaimer cantilever on both sides are installed ultrasonic obstacle detection device, while following the real-time establishment of the coal pallets model and bucket wheel stacker reclaimer cantilever real-time spatial location, the system real-time calculation of their relative position relationship, when the position reaches a certain set value, the host computer for early warning, when the limit value automatically stop rotation and provide alarm, manual confirmation of the exclusion of automatic recovery of rotation, to achieve the cantilever soft and hard Double protection.

Video monitoring: Multi-point industrial-grade high-definition digital network cameras are used to monitor the operation status of the bucket wheel and the environmental conditions of the material yard in all aspects. Video alarm linkage function to improve system security.