Mechanical quick-operation type integrated electro-hydraulic actuator

Abstract

The invention provides a mechanical quick-operation type integrated electro-hydraulic actuator and aims to solve the problems that an electromagnetic valve of a conventional integrated electro-hydraulic actuator for driving a turbine valve is controlled by power, and the reliability is low. The mechanical quick-operation type integrated electro-hydraulic actuator is characterized in that a piston rod of a single-action type hydraulic cylinder is connected with an emergency button of the electromagnetic valve; a reset spring is arranged in a cavity of the single-action type hydraulic cylinder, and low-pressure security protection oil of which the hydraulic pressure is smaller than or equal to 0.3MPa is filled in the other cavity of the single-action type hydraulic cylinder; the connection direction is limited in a way that the electromagnetic valve is in a stop state during shrinkage of the piston rod of the single-action type hydraulic cylinder and compression of the reset spring. The mechanical quick-operation type integrated electro-hydraulic actuator has the positive effects that the motion of the electromagnetic valve is controlled in a hydraulic manner instead of an electric manner, so that the reliability is greatly improved; particularly, the existing electromagnetic valve is controlled on a certain integrated electro-hydraulic actuator by using the low-pressure security protection oil, so that the transformation cost is remarkably reduced.

Description

technical field [0001] The invention relates to an integrated electro-hydraulic actuator for driving the operation of a steam valve of a steam turbine, specifically an integrated electro-hydraulic actuator that uses low-pressure safety oil (less than or equal to 0.3 MPa) to control an electromagnetic valve to realize quick action. Background technique [0002] The integrated electro-hydraulic actuator for driving the valve opening of the steam turbine includes a double-rod cylinder for driving the valve, a quick action circuit controlled by a solenoid valve, and a normal operation circuit controlled by a hydraulic power unit. When the integrated electro-hydraulic actuator is in a normal state, the solenoid valve is closed, the fast action circuit is disconnected, and the double-rod cylinder adjusts the opening of the valve under the control of the normal operation circuit to realize the control of the load or speed of the steam turbine. At this time The load spring on one of...

AI Technical Summary

Problems solved by technology

When the integrated electro-hydraulic actuator is in a normal state, the solenoid valve is closed, the fast action circuit is disconnected, and the double-rod cylinder adjusts the opening of the valve under the control of the normal operation circuit to realize the control of the load or speed of the steam turbine. At this time The load spring on one of the piston rods is always in a compressed state; when it is necessary to quickly close or open the steam valve of the steam turbine, the solenoid valve is charged, the solenoid valve is turned on, and the fast action circuit is connected, that is, the two chambers of the double rod cylinder Connected by the fast action circuit, the piston rod of the double rod cylinder runs quickly under the action of the load spring, driving the steam valve of the steam turbine to close or open quickly within 0.3 seconds, that is, it is controlled by an electric solenoid valve to realize the fast operation of the actuator. At this time, if the control circuit breaks down, the solenoid valve will not operate, and the quick action circuit will not work, so that the rapid closing or opening of the steam valve cannot be realized, and the safety oil of the steam turbine will not work, which will lead to a steam turbine accident.

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