The hottest technological innovation changes indus

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Technological innovation changes industrial process control editor's note: in recent decades, DCS and PLC companies with a long history have turned to the field commonly known as "hybrid control system (HCS)" and tried to combine the powerful function and complexity of DCS system with the flexibility, openness and low price of PLC system

from PLC and DCS to hybrid control

the third generation control system represented by PLC and DCs has achieved rapid development in metallurgical, electric power, petroleum, chemical, light industry and other industrial process control since its application in the 1970s. At that time, plant managers had two basic choices: distributed control system (DCS) or programmable logic controller (PLC). Although the functions of the two systems are similar, they are actually very different. Each has its own advantages and disadvantages. No matter which control system users choose, they often sacrifice another function. In recent decades, DCS and PLC companies with a long history have turned to the field commonly known as "hybrid control system (HCS)" and tried to combine the powerful function and complexity of DCS system with the flexibility, openness and low price of PLC system. For this reason, DCS company reduced the space occupied by its system, while PLC company began to integrate its components to manufacture a more perfect system

zhangweimin, a professor level senior engineer of Tianjin Cement Design Institute, said that as far as the cement industry is concerned, the cement industry is characterized by a large number of switching values, a small number of analog quantities and a small number of loop controls. It is most appropriate to use a hybrid control system. The FC800, PCS7 and Logix introduced by ABB, Siemens and Rockwell mostly belong to the category of hybrid control systems. At the same time, the suppliers of control systems in the cement industry have also applied advanced control algorithms to DCS, PLC and other controllers. ABB's optimize it optimization experts have integrated a large number of industry it proven advanced control technologies and a wide range of expert knowledge bases, such as fuzzy logic, control model, neuron and fuzzy control, to control the cement production process and implement optimal decision management

however, the current market users do not consider the hybrid control system as a revolutionary new product, nor do they regard them as a completely different product. Moreover, in the current domestic market, there are not only the hybrid control system described above, but also the PLC which can realize more process control functions by equipping the loop control board. However, the concept of hybrid control system is in line with the production practice and is the development trend of control system. Theoretically speaking, both DCS and PLC are hybrid control systems, but as a product, hybrid control system undoubtedly provides users with a new choice

modular and discrete design becomes a new trend

the development trend of automation system is from dedicated and centralized control structure to decentralized and independent automation modules. For today's engineering services, although the concept of modularity and availability has been successfully applied to machinery and components close to the hardware level, it still has some limitations in control technology. At present, most of the solutions provided by manufacturers for users are to separate the functions from the various control systems connected by the network. Ideally, the boundaries of mechanical, hardware, and software are consistent

what attracts attention in the automation field is that the control system is developing from centralized to decentralized. Honeywell's Experion PKS platform contains a large number of new technologies, one of which is the distributed system architecture DSA, which embodies the concept of discrete design

the distribution concept of traditional DCS generally stays within one production unit. A set of independent control system is used for a production device. Different operation stations, controllers and i/o are used in different sections to operate and control each section. With the development of modern process industry to super large scale, the relationship between upstream and downstream of each production device is closer, which puts forward new requirements for distributed control system (DCS). It is not only required that each production unit in the whole process should be relatively independent, so as to facilitate the dispersion of hazards, the startup and shutdown of independent units, and the independent installation and maintenance. Moreover, it is required to realize the centralized management and sharing of information of each production device, which is a higher-level distributed control concept. DSA (distributed system architecture) controls each production device with a family called Experion PKS. Each family has an independent real-time process database (erdb) to ensure the independence of each family. Multiple Experion PKS families can be easily integrated into a single system through DSA, without repeated configuration, and seamlessly integrate all DCS data. So as to realize the centralized management and sharing of the information of each production device, form a super large-scale system, and easy to expand

dsa can use various general networks, including local area and wide area. Support microwave, satellite, leased line network, etc., breaking through the dispersion of geographical location. So to speak, Experion? PKS distributed system architecture DSA is a very important trend in the development of control system DCS

wireless technology changes process control system

as the leader of new technologies in the field of process control, Emerson Process Control Co., Ltd. has always regarded wireless technology as one of its key technologies. Linyongchun, marketing director of Emerson Emerson Process control company, pointed out that as wireless technology is further accepted by the public, its application scope is also expanding day by day. Especially in the industrial process field, wireless technology has a huge impact on the industrial process field accustomed to wired technology. So far, most wireless projects are used for open-loop loop loop monitoring. It should be said that the green, safe and edible technology of today's wireless technology polyglutamic acid is a strong supplement to wired technology. Due to the application of wireless technology, the functions that cannot be realized by wired technology due to investment cost and environmental constraints are solved, the process control accuracy is improved, and great benefits are brought to plant management. It should be recognized that the wireless process control is a quiet revolution and a gradual infiltration process. With the improvement of people's awareness and the more reliable, continuous and compatible operation mode of wireless technology, capital participation will bring a stimulating effect to the new material industry and give the entire industry confidence in use. More and more wireless devices will be used in factories. However, safe and effective plant operation always comes first. At present, the application of control functions is still completed through wired cables. At the end of September this year, Emerson launched the redundancy function of the wireless scheme in Orlando, enabling users to have enough confidence to expand the flexible and easy-to-use intelligent wireless platform to the application field of key point monitoring and control

jiangyachun, marketing strategy manager of Honeywell process control department, introduced that the latest version of Honeywell's control system Experion PKS has integrated the wireless network into the control layer, so that wireless devices can participate in the control. Manager jiangyachun said, "we believe that wireless technology will be the development direction of automation control. At the same time, the development of wireless technology will change the structure of process control system."

field bus is upgraded to industrial real-time Ethernet

the development, popularization and application of field bus and industrial Ethernet technology have laid a communication foundation for the formation and development of fully integrated automation architecture. In addition, the formulation, popularization and application of various international automation standards, such as industrial programming language, fieldbus and industrial Ethernet, have also laid a standardized foundation for the development of industrial Ethernet technology

in today's automation field, from the process site level to the plant (Group) management level, the smooth and seamless flow of information can be basically realized through Ethernet. Through the seamless integration of information, process optimization and resource optimization, the integration of logistics, information flow and value flow can be realized, so as to shorten the development cycle of new products, improve quality, reduce costs, improve services and improve the environment, So as to enhance the market adaptability and competitiveness of enterprises. In the field of industrial automation, there are two recognized ones. One is p-net, which is developed based on the poor activity of PROFIBUS system. The other is CIP (industrial network of general industrial protocol), which is mainly developed by Rockwell. It includes DeviceNet, ethernet/ip and controlnet The use and implementation of Ethernet requires the selection and design of different fixture technologies according to different experimental forces and the shape and size of samples. In the past, two wires were used to connect to two-wire instruments at each point. Now, as long as one cable is used, it can directly come down. Not only the cables are greatly reduced, but also the i/0 equipment is greatly reduced

innovation of process instruments can not be ignored

lisurong, product marketing manager of baomeng process instruments, pointed out that no matter how developed the process system is and how powerful the function is, the role of process instruments can not be ignored. She further pointed out that instruments are the basis for detecting, displaying, recording or controlling process parameters in the process of industrial production. With the development of industry, higher requirements are put forward for instrument control system. Electric instruments are gradually developing towards digitalization and intelligence, and computer systems are developing towards networking and openness. The main characteristics of the new generation of instruments are intelligence and digitalization

the production of the factory largely depends on the status of process instruments. These instruments include not only sensors and transmitters for flow, liquid level, pressure, temperature and other parameters, but also analyzers and control valves. Baum sensors and measuring equipment used in process technology are extremely precise and stable, and can fully meet the application requirements. Especially under extreme environmental conditions, they can also make accurate measurements. Good product quality not only extends the service life, but also reduces the maintenance cycle and improves the safety and efficiency of process production

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