With the progress of the times, China's society and economy have seen a new scene of rapid development, and science and technology are constantly improving and updating, which has brought reliable support for the development of industrialization. With the advent of the information age, especially the continuous development of science and technology, it provides better conditions and environment for industrialization.
PLC technology refers to programmable logic controller, which is a control technology to realize digital operation and electronic operating system in industrial environment. It can record, run and control the instructions stored in the memory in a programmable sequence, and at the same time, it can control the output and input of the stored contents by digital and analog means in practical industrial work. The application of PLC programmable logic controller in electrical automation control is the combination of PLC system, computer technology and relay contact control technology, which provides support and reliable guarantee for electrical control automation, not only improves the automation level of electrical control system, but also solves the problems of complex internal wiring, high energy consumption and low reliability of traditional electrical control system, laying a foundation for industrial development.
Analysis of the characteristics of 1 and PLC technology
(1) has strong anti-interference ability and high reliability.
In the previous control system, the use of relays is very common, and the extensive use of relays greatly improves the possibility of failure. Compared with PLC technology, the fault caused by electric shock has been effectively solved. PLC completes the good operation of the system while using less import and export related hardware, which greatly reduces the probability of failure of the operating system. This is because PLC controller, from hardware to software, has strong anti-interference ability, which greatly improves the reliability of system operation.
(2) Simple programming and easy to use.
PLC system can be used only with a certain understanding of programming language, without professional computer-related knowledge. In addition, another advantage of PLC system is to reduce the workload. The development cycle of PLC system is short, and debugging, installation and operation are very simple. Moreover, as long as the online program is modified, the whole system can be changed without disassembling and improving the hardware.
(3) The hardware supporting facilities are perfect and adaptable.
In terms of hardware configuration, PLC controller is equipped with standardized and modular hardware equipment. Through different hardware configurations, the PLC system can be more practical and realize different functions. All these can be operated in the user program, so that various process conditions can be met. Therefore, it can be said that PLC has strong adaptability.
(4) High cost performance and comprehensive functions.
PLC controller can provide users with various programming elements and has powerful control functions. PLC system can realize communication networking, decentralized control and complete centralized management.
(5) simple maintenance.
PLC itself has a certain diagnostic function and display function, so the possibility of failure is extremely low. When there is a problem, the system will display its fault information. At the same time, the diagnostic function starts to find the fault, and then, the fault can be eliminated simply by replacing the module.
2. The application of 2.PLC in electrical automation control.
At first, PLC technology only appeared in the control and application of its switching value. Due to the limitation of scientific and technological level, the data processing and monitoring ability at that time was at a low level, and the service efficiency needed to be continuously improved and improved. Now, with the deepening of industrial reform and the development of science and technology, PLC technology has realized its own transformation and completed its own progress and development. The specific application of PLC technology has the following aspects:
(1) sequence control.
Switch control and sequence control are the main technical control methods in electrical automation auxiliary system. With the requirements of energy saving and emission reduction in power industry production, increasing efficiency and reducing consumption is the content that should be paid attention to, so the requirements for automation control level are also constantly improving. Instead of relay controller, PLC technology plays an important role in electrical automation control. It not only controls a single process flow, but also coordinates and controls all production work under the coordination of information module and communication bus connection. The electric power automation system realizes the automatic control from manual control to computer technical support. The power automation system using PLC mainly includes remote IO station and network structure with field sensors. The remote IO station is connected with the main station layer through the communication bus, and the sensor is connected with the secondary cable through the remote IO station. Through the PLC system at the main station level, the monitoring system can only be operated through the indoor display screen.
(2) The control application of switch quantity.
Electromagnetic relay is a widely used component in the past. Therefore, a large number of contact accidents greatly reduce the reliability of the system. In addition, its own control system also has some problems. After applying PLC technology to electrical automation control, it can be completed only by canceling the relays of some components, which improves the reliability of the system. In addition, it has a complete system and is easy to maintain. On the premise of simplifying the secondary wiring, it is also forbidden to configure the flash power supply.
(3) closed-loop control.
The pump motor can be started automatically by PLC, and its sequence control module can choose the running time of the pump independently, and the staff only need to adjust the field switch. At the same time, when working in the field, the switch must be set to manual gear. At present, the combination of conventional control and PLC control is a common control mode. Electro-hydraulic execution unit, speed measuring unit and electronic adjusting unit constitute the control system of PLC technology, and control other systems respectively.
3 matters needing attention in the application of 3PLC
In actual operation, it is necessary to control the ventilation, temperature and other factors during work. As far as temperature is concerned, PLC should be used in an environment with little temperature change and should be as far away from large mining areas as possible. There are other interference factors that have a negative impact on PLC. If PLC is used in the range of interference sources, the possibility of failure will increase, which will bring unnecessary economic losses and have a certain impact on the work process. Finally, PLC needs to have an independent power supply and keep the grounding wire in a good connection state to prevent great danger in case of accidents.
4. Concluding remarks
To sum up, PLC programmable logic controller has been widely used in the field of industrial control because of its characteristics and advantages. Through closed-loop control, switch quality control and sequence control, the electrical automation control is improved, and its automation level is greatly improved, which provides powerful and reliable help for improving industrial production efficiency and quality. Nowadays, with the rapid development of science and technology in China, the reform of industrial production is also developing towards its own goal, and PLC control system should constantly update and improve itself under this background, and play more roles in the development of electrical automation control.
References:
[1] Wang Shuang, Xu Jian. Application of PLC technology in electrical automation [J]. Electric Power Development, 20 15(0 1):63-65.
[2] Zhang Dongyang. Research on the application of PLC technology in electrical engineering automation control [J]. Scientific and technological progress, 20 14(09):3 1-32.
[3] Chen. On the application and development of PLC in electrical automation control [J]. Science and Technology Herald, 2013 (06):13-15.