外文翻譯---基于plc和組態(tài)軟件的原油儲(chǔ)罐區(qū)監(jiān)督與控制系統(tǒng)

1、翻譯部分2009 3rd International Conference on Power Electronics Systems and Applications PLC and Configuration Software Based Supervisory and Control System for Oil Tanks Area Xi CHEN1 Yanbo CHE1 K.W.E CHENG2 1School of Elect

2、rical Engineering & Automation, Tianjin University, Tianjin China. E-mail: ybche@tju.edu.cn 2Department of Electrical Engineering, The Hong Kong Polytechnic University, Hong Kong, E-mail: eeecheng@polyu.edu.HK Abstra

3、ct - A supervisory and control system for oil tanks area based on PLC S7-300 and configuration software Force Control is introduced in this paper. The hardware structure of the system and the software design are both des

4、cribed in detail. In this system, Superior computers communicate with PLC through Industrial Ethernet. The superior computers system adopts duplex redundancy and the PLC adopts software redundancy .This monitoring syste

5、m integrates the merit of PLC and computer and improves the reliability. Keywords - PLC, configuration software, supervisory and control system, software redundancy I. I NTRODUCTIONWith the increasing competition of

6、the oil marketoil depots are playing a more and more important role, and it has become a long-term important job to supervise and control the operation state of oil depots. This paper designs a supervisory and control sy

7、stem for a oil depot in Shandong Province. This oil depot collected tank information and controlled valves manually before. There were some shortcomings in it such as slow supervisory, great error and low reliability. So

8、 it is necessary to establish a better supervisory and control system that is timely, accurate and reliable. Programmable logic controllers PLC have been widely used in the industrial control fields because of its merits

9、 such as simple structure, flexible functions, high reliability and strong ability in communication. Computers have advantages in the data display and storage, as well as in human-computer communications. This paper desi

10、gns a supervisory and control system for oil tanks area based on PLC and computer. PLC is the control centre and it completes all the details of the control task. It connects with digital and analog signals of field devi

11、ces through general I/O interfaces, collects and process field data accurately and quickly, and completes the logic, timing, counting and mathe maticalo peration seasily. Computers provide human-machine interface, displa

12、y the feild working staste dynamicly, and makes the operation easy. The system combines the advantages of PLC and computer, provides a remote real-time monitoring for the tanks area, ensure safety and reliability and imp

13、roves the work efficiency. Considering oil depot’s high requirements on reliability and continuity, redundancy scheme is designed to improve the reliability further. II. H ARDWARE O F T HE S YSTEMA. the Overall str

14、ucture and functions中國礦業(yè)大學(xué) 2012 屆本科生畢業(yè)設(shè)計(jì) 第 3 頁between the two CPUs. Fig. 2 Hardware structure of PLC CPU315-2DP provides DP master interface and IM153-2 of ET200M provides two DP slave int

15、erfaces ,one is connected to the master station and the other to the reserve station through PROFIBUS-DP networks. PROFIBUS-DP could be Shielded Twisted Pair(RS485) network physically. Normal ET200M consist of a rail, a

16、interface module and some general modules .The modules except power supply are connected through bus connectors. This structure doesn’t support redundantcy functions. There is another configuration that is suitable for r

17、edundantcy. It uses a special rail that can take active bus modules and two interface modules. The modules except power supply are mounted on the active bus modules and it is possible to change modules during running. C.

18、 Connections of the Electrically Operated Valve Henchun CKD series electric operators are used and Fig. 3 shows its connection method. The feedback of electrically operated valve includes four digital signals and one ana

19、log signal. Digital signals are remote mode indicating contact, full open indicating contact, full off indicating contact and common alarm contact. The analog feedback, a 4-20mA current, shows the valve’s opening value .

20、When the valve is in the remote control mode, digital outputs of PLC drive the relays and then control the valves. Four output control signals include open-valve signal, close-valve signal, stop signal and emergency prot

21、ection signal esd. Fig. 3 Valve connection diagram III. SOFTWARE OS THE SYSTEMSoftware in the system includes two major parts, PLC programming software STEP7 V5.4 and superior computer configuration software Force

22、 Control V6.0. A. Communication between Superior Computer and PLC Force Control develops a special driver for the S7-300 PLC, 2009 3rd International Conference on Power Electronics Systems and Applications Digital Refere

23、nce: K210509077 therefore it is not necessary for the users to be familiar with the communication protocol between them, and neither necessary to program or configure network in the PLC, the communication between PC and

24、PLC can be achieved easily. The main problem in this system is that due to PLC's soft redundant structure, when the control task switches to resereve CPU from the master one, Force Control should switch to the correc

25、t communication object to exchange datas. For this purpose, when device PLC is created in Force Control ,it should be configured properly and a data point should be defined in the real-time database as a redundancy switc

26、hing flag. First configure I /O device for Force Control, create PLC whose equipment address is set to 2, if set to 1, Force Control will not be able to connect to the PLC. The standby channel is enabled and the device I

27、P address and standby IP address should correspond with PLC’s two Ethernet communication modules CP343-1. After I/O device PLC is created , define a data point in real-time database whose data type is selected as “ redun