Characteristics and types of electro-hydraulic servo systems

What are the characteristics and types of electro-hydraulic servo systems? Due to its outstanding advantages of fast response speed, large output power and high control accuracy, electro-hydraulic servo systems are widely used in aerospace, military, metallurgy, transportation, engineering machinery and other fields. The electro-hydraulic position servo control system uses liquid as the power transmission and control medium, and uses electrical signals for control input and feedback. As long as a regular input signal is input, the actuator can be started and the change pattern of input quantity can be reproduced quickly and accurately.

Basic requirements for servo system performance

1) High accuracy. The accuracy of a servo system refers to the accuracy of the output being able to reproduce the input.

2) Good stability. Stability means that the system can reach a new or restore to its original equilibrium state after a brief adjustment process under the action of a given input or external interference.

3) Response quickly. Response speed is an important indicator of the dynamic quality of the servo system and reflects the tracking accuracy of the system.

4) Wide speed regulation range. Speed ​​regulation range refers to the ratio between relatively high speed and relatively low speed required by the production machinery.

5) Low speed and high torque. In servo control systems, constant torque control is usually required at low speed, and the motor can provide a large output torque; high-speed constant power control has sufficient output power.

6) It can frequently start, brake, and switch forward and reverse.

Types of servo systems

Depending on the servo drive, servo systems can be divided into three types: electric, hydraulic and pneumatic. According to different functions, it can be divided into metering servo and power servo systems, simulated servo and power servo systems, position servo, speed servo and acceleration servo systems, etc.

According to the electrical signal, the electrical servo system can be divided into DC servo system and AC servo system. There are two types of AC servo systems: induction motor servo system and permanent magnet synchronous motor servo system.