Zhuhai Lingang Industrial Zone Raw Water Supply System Phase 1 of Shamei Pumping Station, with a water supply scale of 300,000 cubic meters/day, covering the supply, installation, programming, commissioning and test operation of high and low voltage distribution and automation control system equipment. acceptance.
First, the network structure 1.1 layered distributed PLC control system, central control room monitoring computer (server) and on-site PLC station, touch screen man-machine interface using fiber optic Ethernet connection, TCP / IP protocol. The on-site PLC station is connected to the controlled equipment and instruments via a fieldbus or hard-wired I/O system. Key equipments such as high-voltage power distribution system, low-voltage power distribution system's main circuit breakers and frequency converters are all equipped with fieldbus interfaces and constitute a fieldbus control system with the PLC master station. Bus communication adopts the international standard MODBUS agreement.
1.2 The control network has one NT server and two ordinary PC workstations (clients) on the control network. The NT server runs industrial control configuration software based on WEB. It also serves as a WEB server. It can integrate various control protocols and generate ODBC support. Real-time database.
1.3 Control Network As a network segment of a company's wide area network, it accesses the company's intranet (based on internet technology).
1.4 Servers and Workstations In addition to pre-installed operating systems and office 2000 office systems, we also provide genuine web-based configuration monitoring software and related programming software and tool software.
Second, automatic control system functions The whole plant process equipment control through three ways: manual mode control, remote control mode and automatic mode control, in the local control box installed "manual - stop - automatic" transfer switch, control conversion.
Control method description:
Manual mode: When the “Manual-Stop-Automatic†switch on the control panel or control cabinet of the equipment is selected at the scene, the local control panel or the button on the control cabinet can be used to start/stop/open the equipment locally. / Off operation.
Remote control mode: When the “manual-stop-automatic†switch on the control panel or control cabinet of the equipment is selected in the field, the “automatic†mode is selected, and “manual†mode or central monitoring room operation is selected on the operation panel of the field device PLC control station. When the “manual†mode is selected in the interface, the control right is in the PLC control station or the central monitoring room. The operator can start/stop and open/close the control of the field device with the mouse or keyboard through the touch screen human-machine operation interface or the monitoring screen of the workstation. Control the equipment under its jurisdiction.
Automatic mode: when the “manual-stop-automatic†switch on the control panel or control cabinet of the equipment is selected in the field to select the “automatic†mode, and the equipment is completely operated when “automatic†mode is selected on the operation panel of the field equipment PLC control station Each PLC automatically completes the operation or on/off control of the equipment according to operating conditions and production requirements.
Central control system data collection and display: Through data communication with each PLC control station, the process parameters, equipment operation status, and high-voltage microcomputer protection device electrical equipment parameters of the whole plant production process are collected and dynamically displayed.
Alarm: set the upper alarm value of each process parameter (such as water level alarm), equipment failure alarm, etc., and have sound and light display.
Parameter setting and equipment control: setting process parameters, upper limit alarm value, and controlling electrical equipment.
Process flow display: Dynamic display of process flow charts, state diagrams of high-voltage power supply systems, process parameters, necessary curve diagrams, and equipment operation status on a color monitor (CRT).
Report Printing: Prints year, month, day, and class run reports, alarm reports, fault reports and process flow charts, and real-time alarm printing and fault printing according to production management requirements.
An uninterrupted power supply is provided to ensure that the system can still operate safely and reliably in the event of a power outage.
The central control room monitors the computer and the on-site touch screen can operate and monitor any networked equipment in the pump station.
Third, hardware technology function
3.1 PLC uses the famous Schneider modular PLC Premium, touch screen is Schneider True Color 10.4 inches.
3.2 On-site PLC adopts the module to make the structure and photoelectrically isolate the I/O module. The module provides insulation protection between the terminals and the terminals and between the terminals and the ground.
3.3 The main power module has a current limiting device and overvoltage protection device.
3.4 PLC has test and fault diagnosis functions.
Fourth, software technology function
4.1 The task of the operator station of the field control station is to set, collect and display the relevant operation information on the standard screen and the user configuration screen so that the operating personnel can monitor and control the operating conditions of the equipment.
4.2 The monitoring system software uses Siemens WinCC V6.0 configuration software and modular design. Chinese interface.
4.3 Each operator station has the following functions:
a. Data is obtained from the server database and is run as a client.
b. Alarm processing: animation sound and light alarm. Alarm queuing, alarm level setting, alarm recovery display, alarm archiving and other functions.
c. Historical data display call
d. Event processing: provide event registration, storage, retrieval and other functions
e. Online production report, fault report generation and random call.
f. Secure login and password protection
g. Operation control function
V. Description of Automatic Control Function According to the process, it is divided into a reservoir pump group control station, a booster pump group control station and a variable frequency pump group control station.
1) Reservoir pump station (1#PLC cabinet)
Monitoring object:
High-voltage power distribution system (without pressure pump high-voltage cabinet and transformer cabinet)
Two water pump groups and its supporting electric control valve, cooling water electric valve 4
10kV high voltage motor
PLC1 field control station is used to collect the process parameters, electrical parameters, and equipment status of the reservoir pump group, and to control the above-mentioned equipment such as the water pump through the fieldbus network or direct I/O.
The PLC1 field control station includes a constant water level control system. When water is discharged from the reservoir to the front pool of the water pumping station, the water level in the discharge pipe of 1.2 m diameter reservoir is controlled to keep the water level in the front pool constant, avoiding the overflow or pumping of the front pool. dry. The selected PLC must have enough control algorithms to support this control function. One touch screen is configured to provide a man-machine interface for monitoring all networked devices in the pump station.
2) Pressure pump station station (2#PLC cabinet)
Monitoring equipment for the pump start / stop control of two sets of booster pump and its supporting electric control valve 4, cooling water electric valve 4. The motor is 10kV direct start.
Beyond tube electric valve control.
The PLC2 field control station is used to collect the process parameters, electrical parameters, and equipment status of the booster pump set, and to control the above-mentioned equipment such as the water pump via a fieldbus network or direct I/O. One touch screen is configured to provide a man-machine interface for monitoring all networked devices in the pump station.
3) Variable frequency pump station (3#PLC cabinet)
The monitoring equipment is a 10kV side circuit breaker for two low voltage transformers (bus control and I/O direct control)
Low-voltage power distribution system: The power distribution system enters two 10/0.38kV transformers and operates in a single busbar section.
Two sets of pumping units and their supporting electric control valves and four cooling water valves.
Two 315kW inverters (bus and I/O direct control)
The PLC3 field control station is used to collect the process parameters, electrical parameters, and equipment status of the variable frequency pump set, and to control the above devices through the fieldbus network or direct I/O.
PLC3 field control station contains a constant water pressure control system. The system detects the water pressure at the end of the pipe network (remote wireless telemetry), adjusts the speed of the inverter, and ensures the water pressure at the end of the pipe network. The PLC station is also the main station of the water pressure telemetry station at the end of the pipeline network and the telemetry station of the reservoir water level. One touch screen is configured to provide a man-machine interface for monitoring all networked devices in the pump station.