A hydraulic actuator

Abstract

The invention provides a hydraulic actuator. The hydraulic actuator comprises an oil cylinder, a main oil pump, a motor for driving the main oil pump, a high-pressure energy accumulator, an oil-return energy accumulator and a controller, wherein a piston rod of the oil cylinder is connected with an actuation component, and the oil cylinder comprises an oil control cavity and an oil return cavity; an oil outlet of the main oil pump is connected with a liquid inlet of a check valve, a liquid outlet of the check valve is connected with a liquid inlet of a first two-position three-way valve through an oil inlet pipeline, a liquid outlet of the first two-position three-way valve is connected with the oil control cavity, and a liquid return port of the first two-position three-way valve is connected with the oil return cavity; an oil inlet of the main oil pump is connected with the oil return cavity through an oil return pipeline, and an oil suction port and a stop valve are sequentially arranged on the oil return pipeline from the main oil pump to the oil return cavity; a fast valve is connected between the oil control cavity and the oil return cavity; the high-pressure energy accumulator is connected with the oil inlet pipeline, and the oil-return energy accumulator is connected with the oil return pipeline between the stop valve and the oil return cavity; and the motor is connected with the controller. According to the hydraulic actuator, an oil tank is not required to be configured, complicated equipment configurations of hydraulic actuators in the prior art are reduced, and the hydraulic actuator is low in investment and convenient to operate and manage.

Description

technical field [0001] The invention relates to a steam turbine control system, in particular to a hydraulic actuator. Background technique [0002] In the prior art, the steam turbine control system is generally composed of man-machine interface, measuring element, control device, actuator and other parts. The man-machine interface is a variety of operation display devices, such as CRT, various indicator lights / meters, mouse, operation buttons / switches, etc. The measuring elements are various sensors, such as speed measuring heads, thermocouples, transmitters, travel switches, etc., which convert various process variables into different forms of electronic signals and send them to the control device. The control device is the core of the entire control system, and realizes various control functions of the system. The commonly used control devices are all digital control systems based on microprocessor and network technology. Since steam turbines are large-scale high-speed...

AI Technical Summary

Problems solved by technology

The seemingly simple idea expands the scale of the EH system, and the oil supply capacity and oil storage capacity of the EH oil supply device need to be recalculated, which objectively increases the burden on the EH system, and the reliability of the EH system decreases with the expansion of the scale

For extraction valves located farther away, this mode is even more unreasonable

If electric or pneumatic actuators are used, the control accuracy and response speed are difficult to meet the requirements of steam turbine control

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