Industrial automation control system refers to the use of some automatic control devices to automatically control certain key parameters in production, so that they can be automatically adjusted to return to the required numerical range of the process when they deviate from the normal state due to external interference (disturbance).
The industrial automation control system consists of a controller and a controlled object. But to achieve complex control tasks, a typical automatic control system should typically also include: fixed value elements, execution elements, measurement and transmission elements, and comparison elements. So, what are the components of an industrial automation control system?
Industrial automation control systems are divided into open-loop control systems and closed-loop control systems based on different control principles.
Open-loop control system
In open-loop control systems, the system output is only controlled by the input, and the control accuracy and interference suppression characteristics are relatively poor. In open-loop control systems, logic control based on time sequence is called sequential control systems; Composed of sequential control devices, detection elements, actuators, and controlled industrial objects. Mainly used for controlling processes such as machinery, chemical engineering, material loading and unloading transportation, as well as robotic arms and production automation lines.
Closed-loop control system
A closed-loop control system is based on the feedback principle, which uses the deviation between the output and the expected value to control the system and achieve good control performance. Closed loop control system, also known as feedback control system.
According to the given signal classification, automatic control systems can be divided into constant value control systems, follow-up control systems, and program control systems.
1. Constant value control system：A system that requires the output of the system to approach the desired value with a certain degree of accuracy while keeping the given value constant. The automatic control system for temperature, pressure, flow rate, liquid level height, and motor speed during the production process belongs to a constant value system.
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. Like a radar antenna system following a satellite.
3. Program control system: The given value changes as a function of time. Such as programmable machine tools.