Application of the hottest PCC in the centralized

Application of PCC in the centralized control system of Tongling port belt conveyor

1 Introduction

the safety and reliability of the centralized monitoring and control system of port belt conveyor (hereinafter referred to as the centralized control system) will directly affect the economic benefits of the port. Therefore, it is very necessary to realize the comprehensive protection and centralized monitoring of the system

the centralized control system with PCC as the core of unqualified products, together with the dispatching system and industrial television system, forms a complete operation, dispatching and monitoring network to realize the telemetry, remote signaling and remote control of the whole system. The implementation of the system improves the production efficiency of port cargo transportation, reduces the equipment accident rate and shortens the fault handling time, simplifies the on-site operators, and improves the overall economic benefits of the port

2 composition and function of centralized control system and its data communication network

2.1 system composition

as a useful supplement to traditional PLC products, PCC (programmable computer controller) programmable computer controller was first introduced by Austrian b&r company in 1994. Compared with PLC (programmable controller) and IPC (industrial control computer), it not only has the high reliability, robustness, flexibility and easy expansibility of PLC, but also has the characteristics of strong computing ability, good real-time performance and convenient programming of IPC. In other words, it combines the advantages of PLC and IPC, especially in human-computer interaction, software programming, debugging environment and debugging monitoring

since the programmable computer controller (PCC) technology entered the automation field in China in the late 1990s, it has been more and more widely used in various industries and other industries in China. With the extensive application of some important domestic hydropower auxiliary equipment enterprises in governor and excitation control, its performance has also been favored and recognized by more and more users. PCC technology has gradually set off a trend of automation technology innovation

because it has many unique advantages, it has better solved the problems of reliability, safety, flexibility, convenience and economy that are widely concerned in the field of industrial control, and PCC is gradually becoming one of the optimal options in the field of industrial automation. Based on the consideration of communication and expansion capacity, the centralized control system of Tongling port belt conveyor selects the PCC 2005 series programmable computer controller (using high-performance Pentium CPU module) of baccalais company as the main control core of the system, and uses a number of 2003 series compact and high-speed PCCS (cp474 CPU module) as the control components and remote i/o of each field control substation, They cooperate with other on-site control/detection equipment, centralized monitoring system and power supply system to monitor and monitor the whole process of multiple belt conveyors in the system, forming a centralized monitoring and control system for port belt conveyors with excellent performance and convenient operation

pcc controller mainly includes CPU module, digital input/output module, analog input/output module, high-speed counter module, etc. as the main control element, it has the advantages of moisture-proof, strong anti-interference ability, easy field programming, easy expansion, supporting high-level language programming and basic maintenance free, and can realize software modularization, automatic detection of system faults, remote maintenance and diagnosis, etc. In addition, the data transmission network (Ethernet, fieldbus and free serial port) can also be formed by the communication interface of PCC to realize data communication in different ways

the centralized control system adopts a distributed control structure, which is composed of field control (mainly including multiple control stations and field control/detection equipment) and centralized control (mainly including servers, operator stations, engineer stations, monitoring centers and monitoring screens). The centralized control part is set in the central control room, and the data communication between it and the field control station adopts Ethernet (tcp/ip protocol). The data communication between the centralized control and the monitoring upper computer of the integrated console is also realized through Ethernet (tcp/ip); Industrial Ethernet is used between the main control station on site and each control substation to realize data communication; The field control station and the sensor are connected through the field bus (Modbus and free port communication protocol are adopted); The field control part is responsible for the control of field equipment and data acquisition. The communication network of the system mainly adopts industrial Ethernet. A repeater must be installed between two control stations with a communication distance longer than 1200 meters, and a field control station must be set at the end of the belt conveyor. Through the monitoring network, the equipment of the whole system can be monitored and centrally controlled. The system structure is shown in Figure 1

Figure 1 structure diagram of port belt conveyor control and monitoring system

2.2 system functions and characteristics

the system adopts real-time monitoring network structure and has perfect production monitoring and management functions. It can collect, transmit, process, display, record and print real-time data in the production process of the main links and related auxiliary links of belt transportation, and remotely monitor the belt transportation system, At the same time, cooperate with the industrial television system to realize safety image monitoring to ensure the safety of personnel and equipment

after the implementation of the monitoring system, the operator can monitor and control the production process of the belt conveyor on the operator station in the central control room, complete the "telemetry, remote signaling and remote control" of the belt conveyor production and related links, and realize the integrated automation of the bulk cargo belt transportation production system. The main functions and characteristics of the system are as follows:

(1) real time operation parameter monitoring. Each monitoring system collects production conditions and process parameters in real time, and displays the real-time working conditions, current output, storage, etc. of the system in the form of graphics and statements

(2) real time process control. Analyze the collected parameters, and each system automatically completes the process control, or manually operated and controlled by the operator

(3) historical data query. The above real-time production monitoring data can be stored in the production data historical database in the server, which can realize historical data re display, historical trend curve analysis, and comprehensive analysis through histograms, pie charts, etc

(4) equipment failure and analog quantity over limit alarm. When the equipment fails or the analog quantity exceeds the limit, the production monitoring and management network synchronously displays the name of the failed equipment, and can realize the functions of voice alarm and real-time fault printing. Store the fault information into the fault information database in the server for offline statistical analysis in the future

(5) optimize the production plan. A comprehensive historical database is established in the web server, and the production, operation and other data are regularly stored in the database. The trend analysis charts of the plan and production completion are made to provide reference for the future production plan; The production plan and equipment maintenance plan shall be reasonably arranged according to the delivery plan, the actual state of the equipment and the amount of stored coal, so as to minimize the impact on production

(6) using advanced controller, the system has good real-time performance, high reliability and fast data processing speed. With fully distributed control structure, the system has high reliability. When there is a control failure in the ground part, the underground part can still realize centralized control operation. Although the distance is far, the communication network speed is fast, the reliability is high, the man-machine interface is intuitive and friendly, the operation is simple, and the functions are complete

(7) reduce wiring costs. Due to the large number of long-distance communication networks, the cable consumption is greatly reduced, the wiring cost is reduced, and the cost is saved. The reliability of the controller and network is high, the maintenance workload is small, the operation cost is low, and the system expansion is also very convenient. Nodes can be added at any time, and the program can be modified in the central control room through the network

2.3 server

the system is equipped with a server to undertake the integrated tasks of application server and real-time and historical data server. Storing complex algorithms and programs in the server and processing complex computing programs; Establish real-time database, historical database and fault information database to store the collected real-time data, historical data and fault information, and call out the historical data when necessary for offline statistical analysis

2.4 operator workstation

according to the functions of the monitoring subsystem, set up the belt transportation system operator monitoring workstation in the monitoring center. Their functions mainly include:

(1) set different operation permissions according to different positions of operators and perform their respective duties; Provide an interactive operation platform with full Chinese interface to realize the visual and dynamic display of the operation status and process parameters of each subsystem equipment; Realize automatic/manual/local control of each subsystem according to the process flow and interlocking relationship

(2) set various operation and production process parameters in real time; Monitor the operating parameters and status of each subsystem equipment in real time, store the parameter data on 1. The positive deviation of the indication exceeds the tolerance hard disk, and upload the necessary data to the data server; Monitor the current status and measurement data of sensors of each subsystem in real time; The fault status of each equipment and important sensors will be alarmed in real time. The audible and visual alarm mode will be adopted, and the alarm information will be printed. At the same time, the alarm information will be stored in the data server for unified management and later analysis of the alarm information; Query and print real-time trend curves and historical trend curves in any specified time period at any time; Query and print historical data reports within any specified period at any time

2.5 engineer workstation

in addition to all the functions of the operator workstation (requiring authorization), the engineer workstation also has the following functions:

(1) modify the application program of the PCC controller according to the adjustment of the process to meet the needs of the new process except for a large number of standard courses

(2) convert the relevant data in the monitoring system and input it into the port information management system

(3) set up a color printer to print real-time color pictures and color trend charts

(4) when the operator workstation of a subsystem fails, the engineer station can be converted into the operator workstation of the subsystem immediately by setting the operator authority

3. Control and monitoring of belt conveyor

3.1 design principles and main technical requirements

the system is composed of belt conveyor, belt feeder and other basic process equipment, and uses control equipment, communication module and skid, stacking, overheating, smoke, longitudinal tearing, dust suppression, speed, deviation, material level and other protective devices to realize the requirements of centralized control and monitoring of belt conveyor. The design principles and main technical requirements are as follows:

(1) realize the centralized monitoring of the belt conveyor system, monitor the equipment status and operating parameters in real time, display the data curve, and record and save the important information

(2) there are three control modes: centralized control automatic/centralized control manual/local, which can be converted to each other. During normal production, the centralized automatic mode is used, and the equipment is automatically started and stopped by the central console according to the sequence and process required by the process; When using centralized control manual mode, all equipment can be operated at the central console, but there is no locking and linkage relationship; When selecting local type, directly operate relevant equipment on site. Before starting the equipment, the central control console sends a warning signal. After 30 seconds, if the on-site equipment meets the conditions for automatic starting of the central control, the equipment will start automatically in sequence. The on-site signal box is equipped with a start/stop button, which can be used to stop the above starting process. If the equipment is started by centralized control, the control system can