In production, various process conditions are never static, especially in chemical production, most of which is continuous production with interconnected equipment. When the process conditions of one piece of equipment change, it can cause fluctuations in certain parameters of other equipment, deviating from the normal process conditions. Of course, automatic adjustment means that no direct human intervention is required.
Automatic control system composition
An automatic control system consists of a controller and a controlled object. However, to achieve complex control tasks, a typical automatic control system should also include: setpoint elements, actuators, measuring and transmitting elements, and comparator elements.
Automatic control system classification
According to different control principles, automatic control systems are divided into open-loop control systems and closed-loop control systems.
1. Open-loop control system: In an open-loop control system, the system output is only controlled by the input, resulting in relatively poor control accuracy and interference suppression characteristics. Among open-loop control systems, those based on time-sequential logic control are called sequential control systems; they consist of sequential control devices, detection elements, actuators, and the controlled industrial object. They are mainly used for controlling processes in machinery, chemical engineering, material handling and transportation, as well as for robotic arms and automated production lines.
2. Closed-loop control system: A closed-loop control system is based on the feedback principle. It uses the deviation between the output and the desired value to control the system, thus achieving better control performance. A closed-loop control system is also known as a feedback control system.
II. According to the given signal, automatic control systems can be classified into constant value control systems, servo control systems, and program control systems.
1. Constant Value Control System: A system where the setpoint remains constant and the system output is required to approach the desired value with a certain precision. Examples of constant value systems include automatic control systems for temperature, pressure, flow rate, liquid level, and motor speed in production processes.
2. Follow-up control system: The given value changes according to an unknown time function, and the output is required to follow the change of the given value. Such as a radar antenna system that follows a satellite.
3. Programmable control system: The given value changes according to a certain time function. Such as a programmable machine tool.
As competition intensifies in the industrial automatic control system device manufacturing industry, mergers and acquisitions and capital operations among large industrial automatic control system device manufacturers are becoming increasingly frequent. Leading domestic industrial automatic control system device manufacturers are paying more and more attention to research on the industry market, especially in-depth research on the industrial development environment and product buyers.
