Controller: The main command device that can change the wiring of the main circuit or control circuit and the resistance value in the circuit in a predetermined order to control the start, speed regulation, braking and reverse rotation of the motor.
Controlled object: generally refers to the controlled equipment or process, such as the control of reactor and rectification equipment, or the control of heat transfer process and combustion process. From the point of view of quantitative analysis and design, the controlled object is only a part of the factors that affect the input and output parameters of the controlled equipment or process, not the whole equipment.
Actuator: liquid, gas, electricity or other energy sources are used and converted into driving action by motors, cylinders or other devices.
Transmitter: The function is to detect process parameters and transmit the measured values in the form of specific signals for display and adjustment. In the automatic detection and regulation system, the function is to convert various process parameters such as temperature, pressure, flow, liquid level, composition and other physical quantities into unified standard signals, and then transmit them to the regulator and indicator recorder for adjustment, indication and recording.
Extended data
system classification
Firstly, according to the different control principles, automatic control systems are divided into open-loop control systems and closed-loop control systems.
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 poor. In the open-loop control system, the logical control based on time sequence is called sequence control system; It consists of sequential control device, detection element, actuator and controlled industrial object. Mainly used in machinery, chemical industry, material handling and transportation, as well as the control of manipulator and production automatic line.
2. Closed-loop control system
Based on the feedback principle, the closed-loop control system uses the deviation between the output and the expected value to control the system, which can obtain better control performance. The closed-loop control system is also called feedback control system.
Second, according to the given signal classification, automatic control system can be divided into fixed value control system, follow-up control system and program control system.
1, fixed value control system
A system that requires the output of the system to approach the expected value with a certain accuracy under the condition that the given value is constant. For example, automatic control systems such as temperature, pressure, flow, liquid level height and motor speed in the production process belong to fixed value systems.
2. Servo control system
The given value changes as an unknown time function, and the output is required to follow the change of the given value. Such as a radar antenna system for tracking satellites.
3. Program control system
The given value varies as a function of time. Such as program-controlled machine tools.
References:
Baidu Encyclopedia-Automatic Control System