CN-121993268-A - Diagnosis method, device and storage medium of DO module for overspeed protection of steam turbine

CN121993268ACN 121993268 ACN121993268 ACN 121993268ACN-121993268-A

Abstract

The invention discloses a diagnosis method, a device and a storage medium of a DO module for overspeed protection of a steam turbine, belonging to the technical field of safety systems; the DO module comprises a plurality of controllable units connected in parallel, each controllable unit comprises a plurality of controllable switches connected in series, each controllable switch comprises a plurality of parallel switch paths, a main control unit sends diagnosis pulses to the corresponding controllable switches, at least one of the parallel switch paths keeps outputting, a diagnosis unit receives the on-off condition returned by the corresponding controllable switch, and the diagnosis unit receives the theoretical value of the diagnosis pulses sent by the main control unit and compares the theoretical value with the actual value of the on-off condition returned by the controllable switch, and if the theoretical value is consistent, diagnosis passes. Only one of the parallel switch paths is diagnosed at the same time, and the other one of the parallel switch paths keeps outputting, so that the undisturbed diagnosis can be realized in different operation modes.

Inventors

WEI LIANGYONG
LI XIANG
WANG FENG
ZHU CHANGYIN
XIAN GUANGQUAN
QU LIANG

Assignees

南京南瑞继保工程技术有限公司
南京南瑞继保电气有限公司
常州博瑞电力自动化设备有限公司

Dates

Publication Date: 20260508
Application Date: 20250924

Claims (10)

1. A diagnosis method of a DO module for overspeed protection of a steam turbine is characterized in that the DO module comprises a plurality of controllable units connected in parallel, each controllable unit comprises a plurality of controllable switches connected in series, each controllable switch comprises a plurality of switch paths connected in parallel, the input ends of the controllable switches in an operation state are connected with the output ends of a corresponding control module and a diagnosis module according to an operation mode, and the control module and the diagnosis module which are connected with different controllable switches in each controllable unit are different; The diagnostic method is applied to a diagnostic unit and comprises the following steps: Receiving a diagnosis pulse theoretical value sent by a main control unit to a diagnosis controllable switch, wherein at least one of parallel switch paths in the diagnosis controllable switch is kept to be output; Receiving an actual value of the on-off condition returned by the controllable switch in diagnosis; the actual value of the on-off condition is compared with the theoretical value of the diagnosis pulse, if so, the diagnosis is passed.
2. The method for diagnosing a DO module for overspeed protection of a steam turbine of claim 1, wherein said control module comprises a CPU_A master unit, a CPU_B master unit and a CPU_C master unit; The DO module comprises a first controllable unit, a second controllable unit and a third controllable unit which are connected in parallel; The first controllable unit comprises a first controllable switch A1 and a fifth controllable switch B2 which are connected in series, the second controllable unit comprises a second controllable switch B1 and a sixth controllable switch C2 which are connected in series, and the third controllable unit comprises a third controllable switch C1 and a fourth controllable switch A2 which are connected in series; The diagnostic module includes an F_A diagnostic unit, an F_B diagnostic unit, and an F_C diagnostic unit.
3. The method of diagnosing a DO module for overspeed protection of a steam turbine according to claim 2, wherein the method of accessing the DO module to the corresponding control module according to the operation mode includes: when the DO module is in 2OO3 mode of operation: The output end of the CPU_A main control unit is connected with the input ends of the first controllable switch A1 and the fourth controllable switch A2, the output end of the CPU_B main control unit is connected with the input ends of the second controllable switch B1 and the fifth controllable switch B2, and the output end of the CPU_C main control unit is connected with the input ends of the third controllable switch C1 and the sixth controllable switch C2; When the DO module is in the 1OO2 mode of operation: the output end of the CPU_A main control unit is connected with the input end of the first controllable switch A1, and the output end of the CPU_B main control unit is connected with the input end of the fifth controllable switch B2; Or, the output end of the CPU_B main control unit is connected with the input end of the second controllable switch B1, and the output end of the CPU_C main control unit is connected with the input end of the sixth controllable switch C2; Or, the output end of the CPU_C main control unit is connected with the input end of the third controllable switch C1, and the output end of the CPU_A main control unit is connected with the input end of the fourth controllable switch A2.
4. The method of diagnosing a DO module for overspeed protection of a steam turbine according to claim 2, wherein the method of accessing the DO module to the corresponding diagnostic module according to the operation mode comprises: when the DO module is in 2OO3 mode of operation: The output end of the F_A diagnosis unit is connected with the input ends of the first controllable switch A1 and the fourth controllable switch A2, the output end of the F_B diagnosis unit is connected with the input ends of the second controllable switch B1 and the fifth controllable switch B2, and the output end of the F_C diagnosis unit is connected with the input ends of the third controllable switch C1 and the sixth controllable switch C2; When the DO module is in the 1OO2 mode of operation: The output end of the F_A diagnosis unit is connected with the input end of the first controllable switch A1, and the output end of the F_B diagnosis unit is connected with the input end of the fifth controllable switch B2; Or, the output end of the F_B diagnosis unit is connected with the input end of the second controllable switch B1, and the output end of the F_C diagnosis unit is connected with the input end of the sixth controllable switch C2; Or, the output end of the F_C diagnosis unit is connected with the input end of the third controllable switch C1, and the output end of the F_A diagnosis unit is connected with the input end of the fourth controllable switch A2.
5. The method of diagnosing a DO module for overspeed protection of a steam turbine of claim 2, wherein each controllable unit is connected in parallel between a 24VDC power supply and a load; the output end of each controllable switch forms an output node of an output voting circuit and is used for providing a digital output result of the DO module, wherein the digital output result of the DO module is as follows: , Wherein, the Representing the logical output of the DO module, Representing the logical output of the first controllable element, Representing the logical output of the second controllable element, Representing the logical output of the third controllable element.
6. The method of claim 5, wherein the logic of the first controllable element is: , the logic of the second controllable unit is as follows: , the logic of the third controllable unit is as follows: 。
7. The method of claim 2, wherein the first controllable switch A1, the second controllable switch B1, the third controllable switch C1, the fourth controllable switch A2, the fifth controllable switch B2 and the sixth controllable switch C2 each comprise two relay contacts connected in parallel.
8. The method of claim 7, wherein the sending, by the main control unit, the diagnostic pulse to the switch path in the corresponding controllable switch, comprises: According to the connection relation between the controllable switch and the main control unit in the current operation mode, the main control unit controls one relay contact in the corresponding controllable switch to be switched on and switched off; the controlled relay contact sends on-off conditions to the diagnosis unit, and the other relay contact keeps an output state; After the controlled relay contact is diagnosed, the main control unit controls the other relay contact to be switched on and switched off, and the diagnosed relay contact keeps an output state.
9. A diagnostic device of a turbine overspeed protection circuit is characterized in that a DO module comprises a plurality of controllable units connected in parallel, each controllable unit comprises a plurality of controllable switches connected in series, each controllable switch comprises a plurality of switch paths connected in parallel, and the input ends of the controllable switches in an operation state are connected with the output ends of a corresponding control module and a diagnostic module according to an operation mode, wherein the control module and the diagnostic module which are connected with different controllable switches in each controllable unit are different; The diagnostic device includes: The diagnosis pulse theoretical value receiving module is used for receiving diagnosis pulse theoretical values sent by the main control unit to the diagnosis controllable switch, wherein at least one parallel switch passage in the diagnosis controllable switch keeps outputting; The on-off condition actual value receiving module is used for receiving the on-off condition actual value returned by the controllable switch in diagnosis; and a contrast diagnosis module: is used for comparing the actual value of the on-off condition with the theoretical value of the diagnosis pulse, if so, the diagnosis is passed.
10. A computer storage medium having stored thereon a computer program which, when executed by a processor, implements a method of diagnosing a DO module for overspeed protection of a steam turbine according to any one of claims 1 to 8.

Description

Diagnosis method, device and storage medium of DO module for overspeed protection of steam turbine Technical Field The invention belongs to the technical field of safety systems, and particularly relates to a diagnosis method, a diagnosis device and a storage medium of a DO module for overspeed protection of a steam turbine. Background The safety architecture design of 2OO3 is mostly adopted in the overspeed protection product of the steam turbine, and at present, aiming at the design architecture, a common diagnosis method is respectively time-sharing diagnosis, as shown in fig. 1, a CPU_A main control unit respectively controls A1 and A2 controllable switches to be turned on and off, and a diagnosis unit reads back the states of the controllable switches to realize diagnosis of the A1 and A2 controllable switches. However, the diagnosis method has the following defects that when the controllable switches A1 and A2 are diagnosed, if any one of the switches B1, B2, C1 and C2 is abnormal, the DO channel can be tripped by mistake, and the factory is stopped in an unplanned way, so that great economic loss is brought to users. The second disadvantage is that when the 2OO3 mode of operation is degraded to the 1OO2 mode of operation, the controllable switch can no longer diagnose, reducing the diagnostic coverage, and reducing the safety of the system. In view of this, how to provide a DO channel and a diagnostic method thereof that solve the above technical problems are the problems that those skilled in the art need to solve. Disclosure of Invention The invention aims to overcome the defects in the prior art and provide a diagnosis method, a diagnosis device and a diagnosis storage medium for a DO module for overspeed protection of a steam turbine, wherein in the diagnosis process, the fault tripping of a DO channel caused by any abnormal controllable switch is avoided, the probability of the fault tripping of a system is reduced, and thus, the economic loss caused by unplanned shutdown of a factory is avoided to a great extent. In order to achieve the above purpose, the invention is realized by adopting the following technical scheme: In a first aspect, the present invention provides a method for diagnosing a DO module for overspeed protection of a steam turbine, comprising: The DO module comprises a plurality of controllable units connected in parallel; the input ends of the controllable switches in the running state are connected with the output ends of the corresponding control module and the diagnosis module according to the running mode, wherein the control module and the diagnosis module which are connected with different controllable switches in each controllable unit are different; The diagnostic method is applied to a diagnostic unit and comprises the following steps: Receiving a diagnosis pulse theoretical value sent by a main control unit to a diagnosis controllable switch, wherein at least one of parallel switch paths in the diagnosis controllable switch is kept to be output; Receiving an actual value of the on-off condition returned by the controllable switch in diagnosis; the actual value of the on-off condition is compared with the theoretical value of the diagnosis pulse, if so, the diagnosis is passed. Optionally, the control module includes a cpu_a master control unit, a cpu_b master control unit, and a cpu_c master control unit; The DO module comprises a first controllable unit, a second controllable unit and a third controllable unit which are connected in parallel; The first controllable unit comprises a first controllable switch A1 and a fifth controllable switch B2 which are connected in series, the second controllable unit comprises a second controllable switch B1 and a sixth controllable switch C2 which are connected in series, and the third controllable unit comprises a third controllable switch C1 and a fourth controllable switch A2 which are connected in series; The diagnostic module includes an F_A diagnostic unit, an F_B diagnostic unit, and an F_C diagnostic unit. Optionally, the method for accessing the DO module to the corresponding control module according to the operation mode includes: when the DO module is in 2OO3 mode of operation: The output end of the CPU_A main control unit is connected with the input ends of the first controllable switch A1 and the fourth controllable switch A2, the output end of the CPU_B main control unit is connected with the input ends of the second controllable switch B1 and the fifth controllable switch B2, and the output end of the CPU_C main control unit is connected with the input ends of the third controllable switch C1 and the sixth controllable switch C2; When the DO module is in the 1OO2 mode of operation: the output end of the CPU_A main control unit is connected with the input end of the first controllable switch A1, and the output end of the CPU_B main control unit is connected with the input end of the fifth controllable switch B2; Or