introduce

With the development of high technology, automation system is gradually applied to industrial production. The application of PLC technology not only solves the problems of complex internal structure, low reliability and high energy consumption of traditional electrical control system, but also saves a lot of manpower and material resources and ensures the working quality of the control system. It has promoted the industrial transformation and healthy development of China, and attracted the attention and attention of more and more professionals.

1, PLC overview

The concept of (1)PLC. In the standard of International Electrotechnical Commission (IEC), ProgrammableLogicController (PLC) is defined as: Programmable logic controller is an electronic system used for digital operation, specially designed for application in industrial environment. In the process of system operation, according to the actual needs of users, with the support of system software, the normal function of the system is ensured. Its working principle is to scan the data of each input point according to the "serial" working mode and send the corresponding signals and data to the output point. The CPU will directly display the executing program commands until the whole program is finished. This process will be repeated after the end. The hardware structure of PLC is generally divided into box type and module type. But their ingredients are the same. For box PLC, there are CPU board, I/O board, display panel, memory block, power supply and so on. Of course, it is divided into several models according to CPU performance and several specifications according to I/O points. For modular PLC, there are CPU module, I/O module, memory, power module, backplane or rack. No matter what type of structure PLC is, it belongs to the open structure of bus, and its I/O ability can be expanded and combined according to the needs of users. Power supply is of great significance to the system operation of PLC. Once there is a problem with the power supply, the PLC will not run normally. Therefore, PLC manufacturers attach great importance to the quality of power supply. The characteristics of the power supply itself determine that the voltage provided can only fluctuate in a small range, so it is necessary to pay attention to the coordination between the power supply and the AC power grid during operation to ensure continuous power supply [1]. CPU is also very important in the operation of PLC system. If PLC is a person, then CPU is the brain of this person. Without a brain, it can't process information and store data, and it can't work. In the operation of the system, its biggest function is to judge the state of the PLC control system, and then send the stored data to the corresponding output devices, so as to ensure that the PLC is always in a good running state. (2) 2) The characteristics of PLC. First of all, the cost performance of PLC is high, mainly reflected in the function. Some functions can only be realized by PLC system, because there are many programming elements in the system, which have very powerful control functions, and can effectively adjust and control the whole electrical automation system, carry out centralized processing and improve work efficiency. Secondly, the most striking feature of PLC is that it is easy to operate, does not need very professional computer knowledge, and the program is simple and easy to operate. As long as you know the programming language, you don't need a long system development cycle, which reduces the amount of calculation and improves the work efficiency and quality. Finally, it has strong adaptability to hardware conditions. PLC has perfect self-checking function and low failure rate. Even if there is a fault, the maintenance is very simple, and it can be handled in a short time, ensuring the stability of the system [2].

2. The practical application of 2.PLC in electrical automation control.

With the update and perfection of PLC technology, this technology has been widely used in electrification control practice. There are three aspects: sequential control, on-off control and closed-loop control. (1) sequence control. With the aggravation of environmental pollution, the country pays more and more attention to energy conservation and emission reduction and sustainable industrial development, and reducing consumption and increasing efficiency in industrial production is our goal. The application of PLC technology realizes the coordination and control of single process flow and full-length production work. For example, in the coal system, a good coal automatic control system design can make the production more stable, and at the same time significantly improve the production efficiency in the use process. The coal control system adopts hierarchical network structure, which can effectively monitor related equipment. Now the coal conveying system basically realizes PLC control, which improves the stability of production, reduces the workload of staff and reduces the waste of manpower and material resources [3]. (2) Switch control. In the process of applying PLC system, virtual relay is regarded as mechanical relay, so the reaction time and return quantity are not considered in the operation process. In this case, the switch control is done well in the process of system operation. Because PLC does not need a lot of physical components and soft relays, its stability is improved. No interference from redundant components, simpler maintenance and more comprehensive functions. In electrical automation, this technology is applied to automatic switching system, which significantly improves the running speed. At the same time, PLC technology can make the standby power supply of the system automatically put into the device, which enhances the reliability of the system in thermal power generation system and is widely used in the production of electric power bureau. The PLC control system can not only reduce the number of auxiliary switches, but also centrally display and control the signals of multiple circuit breakers, which makes the system have the ability of logical judgment, improves the anti-interference ability of the system and realizes the efficient and reliable operation of the system. (3) closed-loop control. There are many ways to start the motor in the electrical automation system, such as manual starting by field control, automatic starting, manual starting by the machine side screen, etc. Compared with other control methods, closed-loop control maintains the relative independence of system equipment, and can ensure the normal operation of system society without other control sources. Closed-loop control is realized by man-machine interaction based on the system. Taking the manual control of the machine-side screen as an example, during the operation of the system equipment, various parameters of the system will appear on the machine-side screen in the form of data, and the operator can know the running state of the system equipment in time through these data, and according to the needs of the system operation,

3. Conclusion

The PLC system can show powerful functions in the application process, which not only overcomes the shortcomings of the traditional system, but also improves the work efficiency. With the further development of science and technology, PLC system will be more optimized and improved, and its application scope will be more extensive and in-depth.

The second paper: the application of PLC in electrical automation control.

1, the main advantages of PLC practical application

In the application practice of PLC system, we have made a technical analysis of its main technical application contents, and found that this technology has the following advantages in practical application. First of all, the automatic control process responds quickly. In the application practice of PLC system, we found that technicians used a new type of automatic management auxiliary relay to complete the control work. Compared with the traditional mechanical relay, this relay control technology uses the internal logic relationship to control in application. So in the actual control process, the node displacement time controlled by it is almost zero, which greatly improves the reaction speed of automatic control. Second, the reliability of the control process is high. In the application practice of PLC system control technology, we found that the control system has good anti-interference ability in practical technical application. Especially in complex industrial production environment, compared with traditional control system, PLC system has high anti-interference characteristics, which ensures the improvement of control reliability of production system. Thirdly, the control operation method is simple. In the actual process of PLC system control, control instructions are completed through a relatively simple control process. These intuitive operating methods can be quickly mastered even by novices. This kind of operation is simple and has great practical effect on the development of control management.

2. Analysis of the main application of PLC system control.

2. 1 Complete the overall control of the electrical system in sequence.

In the actual electrical system control process, it is an important content of the control system to complete the system work sequence control by using control technology. This technical control system can improve the working quality and efficiency of the control system in the actual control process. In the practical application of PLC control system, we find that this control system has a good working mode in sequential control management, so it can replace the traditional relay control system to complete the electrical control of industrial production in practical application. In practical application, we have studied the sequential switching mode of PLC control system and found that its main functions include the following contents. 1. In the practical application of the current PLC control system, sequence control system can not only complete the separate control process, but also connect the information module through the communication bus to realize the overall control of the whole system and even the production workshop. Secondly, in the PLC control system, the main control process is completed through the management of the centralized control room. This independent centralized control management mode can ensure the improvement of automation management efficiency. It is precisely because PLC control system has the above advantages in the process of electrical sequence control that its role in automatic control research has been greatly improved.

2.2 Complete the stable control of the electrical control system.

In the traditional control process of electrical system, the control process of electrical system is mainly completed by electromagnetic relay control system. In practical work, the system is mainly controlled by electromagnetic elements. However, in the actual control process, the reliability of this control system is low, and there are many problems such as complicated wiring and difficult maintenance, which affect its use quality. In the practical application of PLC control system, soft relay is used to control the operation in actual operation, which improves the reliability of its control. At the same time, in the process of operation, the staff can complete the control work with simple operation flow. It is precisely because the PLC control system has the above advantages that it ensures its on-off control in the electrical control system and can play a very good role. In particular, it has the characteristics of strong stability and can play the following roles in the actual electrical control process. First, it has strong stability, which can ensure the improvement of the quality and efficiency of the electrical control process and the improvement of production output. Second, the stable control process can avoid the occurrence of safety accidents. In the actual electrical control process, good switch control can ensure the stable operation of the system, which is a necessary technical support means for safe production. In practice, we found that the good stability of PLC system ensures the stability of system switching control, and it is an important technical support means of automatic control system.

2.3 Complete the automatic management and control of the electrical control system.

In the actual electrical control management, the automatic management control state of PLC system plays an important role in the system control operation. In practice, we found that the PLC automatic control system includes the following work in the actual control process. The first is the automatic control processing of rapid response. Compared with the traditional relay system, in practice, the response time of PLC control system is almost zero, which makes the overall response speed in the control process higher than the traditional control method. This high-speed reaction control process is an important guarantee to realize automatic control. The second is a stable chain control process. In the process of electrical control, it is very important to control the time difference in automatic machining interlocking control. In the PLC control system, because of its high control stability, the smooth completion of chain control is ensured.

3. Research on the future development trend of technology application.

In the technical development of PLC control system, combined with the actual production situation, we carried out the research on the future technology application trend. In the research, we found that the future development trend of PLC control system technology mainly includes the following contents.

3. 1 improves the anti-interference of the whole system.

In the practical application of PLC control system, its good anti-interference characteristics provide a guarantee for the completion of automatic control. Therefore, in the research of PLC control technology, it is necessary to strengthen the technical research on the overall anti-interference of the system, especially in the harsh production environment such as high temperature and high humidity, and in the production environment where electromagnetic interference is serious in the production process. It is of great significance to improve the overall anti-interference of the system for the further application of technology.

3.2 Network and digital trend of system control management

With the popularization of PLC control system, how to better improve its automation process has become an important content of our research. In this process, the application of networking and digitalization of control system has become an important content of our research. In the actual research process, digital and intelligent control technology has been widely used in the application of PLC control technology.

4. Concluding remarks

With the continuous development of automation control technology in modern industrial production, the traditional relay control system has affected the development of automation control technology because of its technical defects. Because of this, we have widely applied PLC control system technology in the research of automation control technology. In practical application, this technology has been widely used because of its good stability and simple control. We do a good job in the technical development and research of the control system, which can provide better theoretical support for the development of industrial production technology.

The third paper: the application of PLC in electrical automation control.

With the development of the times, industry has gradually realized electrical automation, and the application of this technology has greatly promoted the development of industry. In recent years, as a high-tech means, PLC has been widely used in industrial electrical automation to further improve the efficiency of industrial production and promote the development of the whole industry.

1, industrial electrical automation

Industrial electrical automation refers to electrical automation in industrial enterprises, which mainly involves technologies such as electronics, electrical appliances, information, network and electromechanical integration. With the rapid rise of the Internet and computers, electrical automation has been improved widely in time [1]. At present, electrical automation has gradually completed informationization and openness, which has promoted the development of industry to a great extent, and also promoted the development of the whole social economy.

2. Overview, working principle and characteristics of 2.PLC.

PLC, programmable controller, is an automatic control device specially designed for industrial control, which is used to control electrical equipment in industrial production. The reason why the programmable controller can make the operation simple is that it combines many technologies such as electrical control technology, communication technology and computer technology. The working principle of PLC is mainly analyzed according to the working stage, and the working principle of different stages is different. In the input sampling stage, PLC mainly samples data, usually by scanning, and then reads, stores and inputs the collected data into cells [2]. At this stage, it should be noted that the change of input data state will not affect the processing of unit data, so the signal form of reading data should be selected to ensure that data information can be read in any case; In the program execution stage, PLC mainly scans the user program from top to bottom, and obtains the results according to a certain order and video operation; In the output stage of the system, PLC will refresh the user program being executed, and latch the data of the previous stage according to the corresponding state during the refresh process, so as to better drive other peripheral devices. The characteristics of PLC have certain influence on the whole work. In order to ensure that PLC can play its role, this paper will briefly analyze its characteristics. The characteristics of PLC include its reliability, strong anti-interference ability, strong self-diagnosis ability, strong communication ability, fault detection and corresponding information protection and recovery. Its self-checking ability can filter errors in work in time and protect hardware; Its versatility makes PLC easy to operate. In addition, PLC can control production machinery and production lines, and even control the whole production process. Its operation is simple and easy to master, so the training time for relevant personnel is also short, and it can be quickly put into work. The above characteristics of PLC make it widely used in electrical automation.

3. The application of 3.PLC in industrial electrical automation.

3. The application of1PLC in traditional machine tool system

The traditional machine tool system has obvious shortcomings, such as high energy consumption and low efficiency. It is easy to have faults in the industrial production process, which will affect the quality and progress. Once these faults appear, it is very difficult to maintain. In addition, traditional machine tools have always used relay control system, which often leads to various problems such as aging wiring and poor contact, which seriously affects the development of the industry. After PLC is applied to the traditional machine tool system, according to the characteristics of PLC, the software and hardware used in the traditional machine tool are reformed and improved reasonably, and the use state of the machine tool can be known in time through programming, so as to improve the stability of the machine tool operation, enhance the safety of the traditional machine tool and further promote the development of the enterprise. The application of PLC in traditional machine tools is mainly to solve faults and improve efficiency.

3.2 the application of PLC in thermal system

Thermal power system involves many aspects, such as water treatment, coal conveying system, slag discharge system and ash removal system. , are auxiliary systems of thermal power system. PLC can reasonably control these systems according to its own working principle, and at the same time, the communication module in PLC can realize the informationization and openness of data, and promote the mutual coordination of various systems. Among them, the sequential control function of PLC is mainly used for coal conveying system and ash handling system. The coal conveying system is mainly in a hierarchical network structure, which is vertically divided into three layers: main station layer, remote 10 station and field sensor. Programmable controller and man-machine interface equipment constitute the main station layer, and the CPU of OLC is usually equipped with two computers. The control mode of program-controlled copper for coal conveying is centralized control in the control room, and the emergency stop switch and the start-stop button for maintenance are set locally. In the ash removal system, there are mainly conveying fans, gasification fans, ash collection fans and pipeline pressures to be controlled. It usually consists of three parts: the sensor of PLC, the main control cabinet and the secondary instrument. Sometimes, according to the network structure, the operator station and the lower computer controller can go crazy [3]. The switch control function of PLC is needed for the control of circuit breakers and the automatic switching of the system. By reasonably selecting PLC model and compiling feasible control program, the control and signal display of multiple circuit breakers in substation are realized.

4. Concluding remarks

With the continuous development of industrial electrical automation, its technical requirements are getting higher and higher, which makes the production and application of PLC system develop accordingly. The application of PLC in industrial electrical automation not only gives full play to its many functions, but also effectively solves many problems and deficiencies in industrial development. The control system of PLC has strong environmental adaptability, and becomes simple, easy to use and low in energy consumption. It has been widely used in industrial electrical automation, and is gradually called the symbol of industrial electrical automation.