What is the function of an actuator

2025-03-17 11:09:51 49

The actuator is an essential and important component in automatic control systems. Its function is to receive control signals from the controller, change the size of the controlled medium, and maintain the controlled variable at the required value or within a certain range. According to their energy form, actuators can be divided into three categories: pneumatic, hydraulic, and electric. Pneumatic actuators use compressed air as an energy source, characterized by simple structure, reliable and stable operation, high output thrust, easy maintenance, fire and explosion prevention, and low price. Therefore, they are widely used in production processes such as chemical, papermaking, and oil refining, and can be easily matched with passive instruments. Even when using electric instruments or computer control, pneumatic actuators can still be used as long as the electrical signal is converted into a standard pressure signal of 20-100kPa through an electric pneumatic converter or electric pneumatic valve positioner. Electric actuators have convenient energy access and rapid signal transmission, but their structure is complex and their explosion-proof performance is poor. Hydraulic actuators are basically not used in production processes such as chemical engineering and oil refining, and their characteristic is a large output thrust.