Industrial automation control system refers to the use of some automatic control devices, the production of some key parameters for automatic control, so that they are affected by external interference (disturbance) and deviate from the normal state, can be automatically adjusted to return to the process required by the value of the range.
Industrial automation control system consists of controller and controlled object. But to realize the complex control tasks, a typical automatic control system should also include: fixed value elements, actuating elements, measurement and transmission elements and comparison elements. So, the industrial automation control system has that a few components?
Industrial automation control system according to the different control principles, automatic control system is divided into open-loop control system and closed-loop control system.
1. Open-loop control system In the open-loop control system, the output of the system is only controlled by the input, and the control accuracy and interference suppression characteristics are relatively poor. Open-loop control system, based on the logic control in chronological order is called sequential control system; composed of sequential control devices, detection elements, actuators and controlled industrial objects. Mainly used in machinery, chemical industry, material handling and transportation process control, as well as robots and production lines.
2. Closed-loop control system Closed-loop control system is based on the principle of feedback, the use of the output deviation from the desired value of the system for control, you can get a better control performance. Closed-loop control system is also known as feedback control system.
According to the classification of the given signal, the automatic control system can be divided into constant value control system, follower control system and program control system.
1. Constant value control system The given value is unchanged, and the output of the system is required to be close to the given desired value with a certain accuracy. Such as the production process of temperature, pressure, flow, level height, motor speed and other automatic control systems belong to the constant value system.
2. Follow the control system: the given value changes as a function of unknown time, the output is required to follow the changes in the given value. Such as following the satellite radar antenna system.
3. Program control system: the given value changes according to a certain time function. Such as program-controlled machine tools.