Commonly used automation control systems and 3 development directions of automatic control system
The automatic control system is mainly composed of four links
- controlled object
- Controller: The main command device that can change the wiring of the main circuit or the control circuit and change the resistance value in the circuit according to a predetermined order to control the starting, speed regulation, braking and reverse direction of the motor.
- Controlled object: generally, refers to the controlled equipment or process as the object, such as the control of reactor, rectification equipment, or the control of heat transfer process, combustion process, etc. From the perspective of quantitative analysis and design, the control object is only a part of the factors affecting the input and output parameters of the object in the controlled equipment or process, not the whole of the equipment.
- Actuator: Use liquid, gas, electricity or other energy and convert it into driving action through motor , cylinder or other device.
- Transmitter: The function is to detect process parameters and transmit the measured value in the form of a specific signal for display and adjustment. The function in the automatic detection and adjustment system is to convert various process parameters such as temperature, pressure, flow rate, liquid level, composition and other physical quantities into unified standard signals, and then transmit them to the regulator and indicating recorder for adjustment, indication and Record.
Three development directions of automatic control system
- Fieldbus control system
Fieldbus Control System (FCS) is a two-way serial, digital, multi-node communication network connecting field intelligent equipment and automation control equipment. It is also known as Field Bottom Device Control Network.
At present, FCS based on field bus develops very fast, but there is still a lot of work to be done in the development of FCS, such as unified standards and intelligent instruments . It is certain that FCS combined with new technologies such as DCS , industrial Ethernet , and advanced control will have strong vitality.
- Industrial PC control system
Due to the openness of PCs, abundant hardware resources, software resources and human resources, and the characteristics of low cost, industrial control systems based on PCs (including embedded PCs) are growing at a rate of more than 20% per year. The industrial control technology of PC has become one of the mainstream technologies at the beginning of this century.
- Intelligent management and control integration system integration
With the development of computer technology, communication technology and control technology, the traditional control field is experiencing an unprecedented change and begins to develop in the direction of networking. The requirements for large data volume and high-speed transmission such as images and voice signals have spawned the combination of Ethernet and control networks that are currently popular in the commercial field.
This wave of industrial control system networking integrates a variety of today’s popular technologies such as embedded technology, multi-standard industrial control network interconnection, and wireless technology, thereby expanding the development space in the field of industrial control and bringing new development opportunities.