Fault diagnosis method and system for valve opening process of quick closing valve of feed pump steam turbine

Abstract

The invention discloses a fault diagnosis method for the valve opening process of a quick closing valve of a feed pump steam turbine. The fault diagnosis method comprises the steps that a start instruction is sent to a quick closing oil control valve and a starting oil control valve; the output oil pressure of the quick closing oil control valve and the starting oil control valve is monitored in real time; whether the output oil pressure reaches the rated quick closing oil pressure within the time frame of 0-t1 or not is judged, and if no, faults happen to the quick closing oil control valve;if yes, whether the output oil pressure is kept within the allowable quick closing oil pressure range within the time frame of t1-t2 or not is judged, and if no, the action of an electric control signal circuit of the quick closing oil control valve is normal, and faults happen to a mechanical valve or an oil way; whether the output oil pressure reaches the rated starting oil pressure within the time frame of 0-t1 or not is judged, and if no, faults happen to the starting oil control valve; and if yes, whether the output oil pressure is kept within the allowable starting oil pressure range within the time frame of t1-t2 or not is judged, and if no, the action of an electric control signal circuit of the starting oil control valve is normal, and faults happen to the mechanical valve or theoil way. The invention further discloses a fault diagnosis system for the valve opening process of the quick closing valve of the feed pump steam turbine. The beneficial effects of the system are as mentioned.

Description

technical field [0001] The invention relates to the technical field of thermal power generation, in particular to a method for diagnosing a fault in the valve opening process of a feed water pump steam turbine quick closing valve. The invention also relates to a fault diagnosis system for the valve opening process of the quick closing valve of the steam turbine of the feed water pump. Background technique [0002] With the development of thermal power generation technology, more and more power equipment has been widely used. [0003] The feedwater pump turbine is an important auxiliary equipment in a thermal power plant. It is responsible for providing high-pressure accumulated water to the boiler. Its safe operation is of great significance to the power plant. For the feedwater pump turbine that adopts quick-closing components and quick-closing valves, whether the quick-closing valve can be opened normally is the main condition for the success of the feedwater pump turbine...

AI Technical Summary

Problems solved by technology

However, due to the different force conditions, the feed pump turbine with the quick-closing valve can be opened normally under static conditions. When there is steam in front of the quick-closing valve or the steam pressure in front of the quick-closing valve is high, the quick-closing valve may start during the opening process. Changes in oil pressure and quick shut-off oil pressure, and failure of the feedwater pump and steam turbine to hang brakes will affect the reliable operation of the power plant and have a negative impact on the normal load of the power plant

[0004] At present, when there is steam in front of the quick-closing valve of the feed pump steam turbine or the steam pressure is high, the problem of low quick-closing oil pressure and failure to hang the gate is prone to occur during the gate-hanging process. The original system is only designed with a local pressure gauge, which needs to be operated when starting On-site monitoring by personnel, the oil pressure situation is inconvenient to monitor and cannot be reproduced, and it is inconvenient to analyze accidents

At the same time, the quick-closing valve is affected by two oils at the same time during the opening process, that is, the starting oil and the quick-closing oil. Affected, for example, the oil pressure will fluctuate, which will cause the solenoid valve controlling the starting oil and the solenoid valve controlling the quick closing oil to malfunction

However, since the steam pressure in front of the quick-closing valve will affect both the starting oil circuit and the quick-closing oil circuit at the same time, in the prior art, technicians cannot accurately judge whether the operating failure occurred in the starting oil circuit or the quick-closing oil circuit. It is easy to cause the maintenance schedule to be delayed, the maintenance time to be wasted, and the maintenance cost to be too high

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