Thermal power plant ETS system shutdown button design method

Abstract

The invention relates to a thermal power plant ETS system shutdown button design method. The method comprises the steps that a shutdown button A and a shutdown button B are divided into three normallyopen nodes to enter an ETS system, three independent cables are independently laid and connected into three I/O clamping pieces of the ETS system respectively, whole-course independent design of protection signals is achieved, and two-out-of-three post-phase and output are conducted in the ETS system respectively. When any contact or signal of the shutdown button A and the shutdown button B breaks down, a two-out-of-three algorithm is executed through logical operation, so that protection signals are normally output, and the protection refusal condition is avoided. The shutdown buttons A andB are independent of the ETS system, and an electromagnetic valve is directly driven to act through a hard loop. The reliability of shutdown button A/B protection can be effectively improved, and protection maloperation and refusal are avoided.

Description

Technical field [0001] The invention belongs to the technical field of thermal power generation, and in particular relates to a method for designing a shutdown button of an ETS system in a thermal power plant. Background technique [0002] In the steam turbine unit of thermal power plant, ETS system is very important. If the system does not operate effectively, it may cause malfunction or refusal to operate, which may cause damage to the steam turbine components. Therefore, whether the ETS system protection design is perfect and whether it meets the standard requirements is particularly important. [0003] The protection design schemes of the ETS system of steam turbine units in the prior art mainly include the following two types: [0004] 1) Stop the hard hand-operated button to drive the logic action of the ETS system by connecting a normally open node to the switch input channel of the ETS system, and output the protection action command after the logic "AND" operation in the E...

AI Technical Summary

Problems solved by technology

[0009] The purpose of the present invention is to provide a design method for the stop button of the ETS system in a thermal power plant, which can solve the design defect of the hard manual button to access the ETS system signal, avoid the risk of protection refusal due to a point of wiring failure or a button contact failure, and solve the problem of hard The manual button is directly independent of the ETS system to drive the AST solenoid valve tripping circuit design defect, avoiding the risk of protection misoperation due to a point of wiring failure or button contact failure

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