What does hydraulic servo system mean?
The gas-liquid servo system is used for explosion-proof environments or for easy access to air pressure signals. The hydraulic servo system should have the necessary properties: job stability; Quick response to command signals; The steady state error is small; Not sensitive to interference. Hydraulic servo system is the most widely used in automatic control system. The hydraulic servo system can guarantee the machining error of less than 0.1 micron in the precision machined positioning system. There are many great astronomical expectations in the world
The hydraulic servo system is widely used in industrial control with its unique advantages such as fast response speed, high load stiffness and large power control. Electro-hydraulic servo system by using the electro-hydraulic servo valve, transforms the electrical signal of small power for high power hydraulic power, so as to realize the servo control of some heavy machinery equipment. The diagram shows an electro-hydraulic servo system that is continuously controlled for pipe flow. In the large-diameter fluid pipeline 1, the Angle theta change of valve plate 2 will be used to regulate the flow of qT. The disc rotation is actualized by the hydraulic cylinder driving gear and rack. The input quantity of this system is the given value xi of the potentiometer 5. Have certain voltage corresponding to the given value of xi, 7 loss to the amplifier, the amplifier converts voltage signal to the electromagnetic coil current signal to the servo valve, the valve core accordingly produce certain amount of opening xv. Valve opening xv allows hydraulic oil to move into the hydraulic cylinder and push the hydraulic cylinder down. The oil in the lower chamber of the hydraulic cylinder is returned to the tank by the servo valve. The downward movement of the hydraulic cylinder causes the gears and rack to drive the valve plates to deflect. At the same time, the hydraulic cylinder piston rod also drives the contact point of the potentiometer 6. When the voltage corresponding to x is the same as the voltage corresponding to xi, the difference between the two voltages is zero. At this point, the output current of the amplifier is zero, the servo valve is closed, and the hydraulic cylinder is positioned in the corresponding qT position.
Hydraulic servo system is to make the system output, such as displacement, velocity, or force, can automatically, quickly and accurately follow the change of the input and change, at the same time, the output power is greatly enlarged.
The hydraulic automatic control system with the action in the hydraulic drive. In this system, high-power hydraulic elements (including hydraulic servo and hydraulic actuator) follow the small power command signal element actions. The execution element is usually controlled by the position, speed, and so on. The instruction signal component is also called the reference signal component, which emits an instruction signal for position, velocity, or other quantity. Large power can be several million times smaller than small power. Is a feedback control system for hydraulic servo system, the feedback signals and instructions of the actual status of the representative comparison, get the error signal, if the error is not zero, then. In anti-aircraft gun automatic aiming system, for example, the radar tracking planes, and send signals to the director, the director to calculate the anti-aircraft gun tube should be located, the actual location of the barrel with the director to calculate the instruction location constant comparison and adjustment in the system, until the error is less than the permission value when shooting. The hydraulic servo system should include the actual measurement of the feedback component. The transmission component of the small power command signal and the high power hydraulic actuator; The comparison component of the expected state and the feedback state; Amplification of the difference signal. Hydraulic servo system is divided into mechanical hydraulic servo system, electro-hydraulic servo system and pneumatic hydraulic servo system.
