Intelligent, high-precision: Introduction to the development trend of industrial automation instruments

Advances in information technology have driven the advancement of industrial automation instrumentation and control systems. The following directions are briefly described below:

Intelligent 

From the development trend of industry and automation instrumentation, intelligence is the core part, and the so-called intelligent performance has many new functions. For example, in the past, when the flow meter needed to perform temperature and pressure compensation, three transmitters for measuring flow, temperature and pressure were needed, and an arithmetic unit was needed for calculation. Now an intelligent flow transmitter can take this. A task; another example is an intelligent actuator, which has a variety of self-diagnostic functions, making maintenance forecasting possible. For example, when the stroke of the valve stem of the actuator regulating valve exceeds a certain length, a signal is sent to the maintenance personnel to replace the sealing packing; and when the valve moves too frequently, the worker can be notified to intervene to avoid an accident; When used in corrosive media, if it exceeds a certain flow rate and working time, it can also send a signal for timely replacement, because there is no material that will never corrode. 

 In the aspect of industrial control, the algorithm of the past control can only be done by the regulator or DCS. Now an intelligent transmitter or actuator can be connected with the relevant field instrument as long as the PID module is implanted. Autonomous adjustment is realized in the field; thus, the control is completely dispersed, thereby reducing the burden on the DCS host, making the adjustment more timely, and improving the reliability of the entire system. 

High precision 

 Due to the increasing requirements for the quality of finished products in industrial production, national policies and laws have specific requirements and regulations for energy conservation and emission reduction. Therefore, the accuracy of measuring instruments and control systems has been put on the agenda. For example, the accuracy of the transmitter has generally increased from 0.77 percent to 0.04 percent. The accuracy of the Coriolis mass flowmeter for trade exchange measurement has reached 0.05%, and the accuracy of some gas ultrasonic flowmeters has reached 0.5%. At the same time, the new generation of DCS also serves as a Important indicators. 

 At present, some new large-scale projects have made clear requirements for the accuracy of the products at the time of bidding. This is both a threshold and a requirement for the resources of the manufacturer. 

 Wireless 

现场 Fieldbus is a very promising technology, which should be rapidly developed and promoted. However, due to the excessive number of international standards, it has affected the promotion. For example, the international standard of the first-generation bus-type fieldbus has reached more than 10 By the end of the year, coupled with the second generation of real-time industrial Ethernet, there may be more than 20 international standards, and the third generation of bus communication solutions are emerging, and major multinational companies and related organizations are developing. The respective standards, currently known as HART wireless, ISA SP100, IEC, as well as Emerson, Siemens and other large companies are developing their own wireless standards. Too many standards are not a good sign for users. Users hope to work hard to develop a single international standard. 

 Industrial production requires high yield, stability, quality, low consumption, safety and environmental protection. With the increasing scale of production, such as the thermal power unit has 1 million KW supercritical units; the refinery has reached 10 million tons, the ethylene plant has reached the scale of 1 million tons, and the points of measurement and control are increasing. Generally it has reached more than 10,000 points. If the field instrument can realize wireless communication, the number of cables and maintenance workers will be greatly reduced, and the construction design department and end users will be welcome. Therefore, research and development of close-range, low-power and reliable wireless communication is a bright spot.