Reactor diversified signal protection system and control method

Abstract

The invention relates to the technical field of nuclear power plant reactor diversified protection signals, in particular to a reactor diversified signal protection system and a control method. The system comprises a measurement unit, processing transmission channels, a control unit and a delay link, the measurement unit continuously measures measurement parameters, and the processing transmission channels comprise a main protection processing transmission channel and a diversified protection processing transmission channel. The measurement unit transmits measurement parameters to the main protection processing transmission channel and the diversified protection processing transmission channel, the processing transmission channel processes the measurement parameters and transmits the measurement parameters to the main protection control unit and the diversified protection control unit, and a delay link is arranged in the diversified protection processing transmission channel. According to the invention, the diversified protection signal of the reactor can be prevented from being triggered prior to the main protection signal, and the protection signal related to the diversified protection system is not triggered or is triggered after the protection signal of the main protection system is triggered when the main protection system can work normally.

Description

Technical Field

[0001] The present invention relates to the technical field of diversified protection signals for reactors in nuclear power plants, and in particular to a reactor diversified signal protection system and a control method. Background Art

[0002] The reactor protection system of Hualong One and subsequent nuclear power plants is equipped with a diversified protection system to deal with the loss of protection function of the main protection system due to software common cause failure (SWCCF). In the event of SWCCF in the main protection system, the diversified protection system provides necessary protection for the reactor to ensure reactor safety.

[0003] As a backup for the main protection system, the diversified protection system should ensure that the main protection system will act first when the reactor protection system is required to provide protection in an accident, and the diversified protection system will act later or not act at all when the main protection system can work normally. To achieve this goal, it is necessary to set reasonable diversified protection signal setting values ​​and delay times. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a reactor diversified signal protection system and a control method. By setting a reasonable diversified protection system protection signal setting value and delay time, it is possible to avoid the reactor diversified protection signal being triggered before the main protection signal, thereby ensuring that when the main protection system can work normally, the protection signal related to the diversified protection system is not triggered or is triggered only after the main protection system protection signal is triggered.

[0005] The technical solution adopted by the present invention is:

[0006] A reactor diversified signal protection system comprises a measuring unit, a processing transmission channel, a control unit and a delay link, wherein the measuring unit continuously measures measurement parameters, the processing transmission channel comprises a main protection processing transmission channel and a diversified protection processing transmission channel, the measuring unit transmits the measurement parameters to the main protection processing transmission channel and the diversified protection processing transmission channel respectively, the processing transmission channel processes the measurement parameters and transmits them to the main protection control unit and the diversified protection control unit respectively, and a delay link is arranged in the diversified protection processing transmission channel.

[0007] The measurement parameters include reactor neutron injection rate, pressurizer pressure, coolant flow rate, steam flow rate, and steam pressure.

[0008] The main protection control unit and the diversified protection control unit are provided with trigger logic to trigger the emergency shutdown or a dedicated drive, and by setting different trigger setting values, the diversified protection action is made later than the main protection trigger.

[0009] A control method for a reactor diversified signal protection system sets an appropriate offset between a protection signal setting value of the diversified protection system and a protection signal setting value of a main protection system, and sets an appropriate delay link for the T2 response time of the protection signal of the diversified protection system, thereby ensuring that the protection signal of the diversified protection system is issued later than that of the main protection system.

[0010] The specific steps include:

[0011] Step 1: setting an appropriate offset between the protection signal setting value of the reactor main protection system and the protection signal setting value of the diversified protection system, and calculating the signal setting value of the diversified protection system;

[0012] Step 2: On the basis of setting an offset between the setting value of the protection signal of the main protection system and the setting value of the diversified protection signal, a certain delay link is set for the protection signal of the diversified protection system.

[0013] The calculation method of the offset is as follows: define the main protection system channel error as CS1, the diversified protection system channel error as CS2, and the minimum offset CS' between the diversified protection system protection signal setting value and the main protection system protection signal setting value is:

[0014]

[0015] In the above formula, R is the range of the signal, and the unit is the physical unit of the measured variable;

[0016] The offset σ between the protection signal setting value of the diversified protection system and the protection signal setting value of the main protection system can be expressed as:

[0017] σ=CS'+M (2)

[0018] In the above formula, M is the margin used in safety analysis, and its unit is the physical unit of the measured variable.

[0019] After determining the offset, the signal setting value of the diversified protection system is expressed as follows:

[0020] S DAS =S RPS / ESFAS ±σ (3)

[0021] In the above formula, S DAS It is the signal setting value of the diversified protection system. “±” means adding (or subtracting) the deviation according to the situation. RPS / ESFAS Signal setting value for the main protection system.

[0022] The sensor portion is not taken into account when calculating the offset.

[0023] In step 2, the sensor response time T1 of the main protection system and the diversified protection system is the same, and a certain delay link is considered for T2 of the diversified protection system: the protection action triggering time of the main protection system is T RT(RPS) / action(ESFAS) =T1+T 2(RPS / ESFAS) , the protection action triggering time of the diversified protection system is T RT / action(DAS) =T1+T 2(DAS) +T 2delay(DAS) ;

[0024] In the above formula, T RT(RPS) / action(ESFAS) The main protection system action response time, T RT / action(DAS) is the action response time of the diversified protection system; T1 is the sensor response time; T 2(RPS / ESFAS) The response time from the output of the main protection system sensor to the input of the trip circuit breaker or the response time from the output of the measuring sensor to the issuance of a dedicated trigger signal, T 2(DAS) The corresponding response time of the diversified protection system; T 2delay(DAS) Delay time set for the diversified protection system.

[0025] When T 2(DAS) Less than T 2(RPS / ESFAS) In this case, the diversified protection signal is issued earlier than the main protection signal.

[0026] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0027] (1) The present invention provides a reactor diversified signal protection system and control method, which sets an appropriate offset between the set value of the protection signal of the diversified protection system and the set value of the protection signal of the main protection system, and sets an appropriate delay time for the processing link of the protection signal of the diversified protection system, thereby ensuring that the protection signal of the diversified protection system is issued later than that of the main protection system.

[0028] (2) The reactor diversified signal protection system and control method provided by the present invention can be applied to the design of advanced pressurized water reactor nuclear power plants (stations), and has a broad application prospect. The present invention has an internationally leading technical level. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0030] Figure 1 A schematic diagram of the structure of a reactor diversified signal protection system provided by the present invention;

[0031] Figure 2 A schematic diagram of the design of reactor diversified signal setting values ​​and delay times provided by the present invention. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0034] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] like Figure 1 As shown, a reactor diversified signal protection system provided by the present invention includes a measuring unit, a processing transmission channel, a control unit and a delay link. The measuring unit continuously measures reactor protection parameters such as reactor neutron injection rate, stabilizer pressure, coolant flow, steam flow, steam pressure, etc. The processing transmission channel includes a main protection processing transmission channel and a diversified protection processing transmission channel. The measuring unit transmits the measurement parameters to the main protection processing transmission channel and the diversified protection processing transmission channel respectively. The processing transmission channel processes the measurement parameters and transmits them to the main protection control unit and the diversified protection control unit respectively. In order to avoid the diversified protection unit being triggered earlier than the main protection unit, a delay link is set in the diversified protection processing transmission channel.

[0036] The trigger logic is set in the main protection control unit and the diversified protection control unit to trigger the emergency shutdown or dedicated drive. By setting different trigger setting values, the diversified protection action is made later than the main protection trigger.

[0037] like Figure 2 As shown, a control method for a reactor diversified signal protection system sets an appropriate offset between the protection signal setting value of the diversified protection system and the protection signal setting value of the main protection system, and sets an appropriate delay link for the T2 response time of the protection signal of the diversified protection system, which can ensure that the protection signal of the diversified protection system is issued later than that of the main protection system. Specifically, the following steps are included:

[0038] Step 1: setting an appropriate offset between the protection signal setting value of the reactor main protection system and the protection signal setting value of the diversified protection system, and calculating the signal setting value of the diversified protection system;

[0039] The calculation method of the offset is as follows: define the main protection system channel error as CS1, the diversified protection system channel error as CS2, and the minimum offset CS' between the diversified protection system protection signal setting value and the main protection system protection signal setting value is:

[0040]

[0041] In the above formula, R is the measuring range of the signal, and the unit is the physical unit of the measured variable.

[0042] Since the sensor is shared by the main protection system and the diversified protection system, the sensor part is not considered when calculating the offset.

[0043] The offset σ between the protection signal setting value of the diversified protection system and the protection signal setting value of the main protection system can be expressed as:

[0044] σ=CS'+M (2)

[0045] In the above formula, M is the margin used in safety analysis, and its unit is the physical unit of the measured variable.

[0046] After determining the offset, the signal setting value of the diversified protection system can be expressed as follows:

[0047] S DAS =S RPS / ESFAS ±σ (3)

[0048] In the above formula, S DAS It is the signal setting value of the diversified protection system. “±” means adding (or subtracting) the deviation according to the situation. RPS / ESFAS Signal setting value for the main protection system.

[0049] Step 2: On the basis of setting an offset between the setting value of the protection signal of the main protection system and the setting value of the diversified protection signal, a certain delay link is set for the protection signal of the diversified protection system:

[0050] The sensor response time T1 of the main protection system and the diversified protection system is the same. A certain delay link is considered for T2 of the diversified protection system: the protection action trigger time of the main protection system is T RT(RPS) / action(ESFAS) =T1+T 2(RPS / ESFAS) , the protection action triggering time of the diversified protection system is T RT / action(DAS) =T1+T 2(DAS) +T 2delay(DAS) .

[0051] In the above formula, T RT(RPS) / action(ESFAS) The main protection system action response time, T RT / action(DAS) is the action response time of the diversified protection system; T1 is the sensor response time; T 2(RPS / ESFAS) The response time from the output of the main protection system sensor to the input of the trip circuit breaker (trip unit de-energized) (emergency trip signal) or the response time from the output of the measuring sensor to the issuance of a dedicated trigger signal (dedicated signal), T 2(DAS) The corresponding response time of the diversified protection system; T 2delay(DAS) Delay time set for the diversified protection system.

[0052] This design can avoid the small difference in the arrival time of the protection signal setting values ​​of the main protection and diversified protection systems in the transient state of rapid change of protection parameters, and T 2(DAS) Less than T 2(RPS / ESFAS) In this case, the diversified protection signal is issued earlier than the main protection signal.

[0053] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0054] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A reactor diversified signal protection system, characterized in that: It includes a measuring unit, a processing transmission channel, a control unit and a delay link. The measuring unit continuously measures the measurement parameters. The processing transmission channel includes a main protection processing transmission channel and a diversified protection processing transmission channel. The measuring unit transmits the measurement parameters to the main protection processing transmission channel and the diversified protection processing transmission channel respectively. The processing transmission channel processes the measurement parameters and transmits them to the main protection control unit and the diversified protection control unit respectively. A delay link is set in the diversified protection processing transmission channel.

2. The reactor diversified signal protection system according to claim 1, characterized in that: The measurement parameters include reactor neutron injection rate, pressurizer pressure, coolant flow rate, steam flow rate, and steam pressure.

3. The reactor diversified signal protection system according to claim 1, characterized in that: The main protection control unit and the diversified protection control unit are provided with trigger logic to trigger the emergency shutdown or a dedicated drive, and by setting different trigger setting values, the diversified protection action is made later than the main protection trigger.

4. A control method for a reactor diversified signal protection system, characterized in that: By setting an appropriate offset between the setting value of the protection signal of the diversified protection system and the setting value of the protection signal of the main protection system, and setting an appropriate delay link for the T2 response time of the protection signal of the diversified protection system, it can be ensured that the protection signal of the diversified protection system is issued later than that of the main protection system.

5. The control method of the reactor diversified signal protection system according to claim 4, characterized in that: The specific steps include: Step 1: setting an appropriate offset between the protection signal setting value of the reactor main protection system and the protection signal setting value of the diversified protection system, and calculating the signal setting value of the diversified protection system; Step 2: On the basis of setting an offset between the setting value of the protection signal of the main protection system and the setting value of the diversified protection signal, a certain delay link is set for the protection signal of the diversified protection system.

6. The control method of the reactor diversified signal protection system according to claim 5, characterized in that: The calculation method of the offset is as follows: define the main protection system channel error as CS1, the diversified protection system channel error as CS2, and the minimum offset CS' between the diversified protection system protection signal setting value and the main protection system protection signal setting value is: In the above formula, R is the range of the signal, and the unit is the physical unit of the measured variable; The offset σ between the protection signal setting value of the diversified protection system and the protection signal setting value of the main protection system can be expressed as: σ=CS'+M (2) In the above formula, M is the margin used in safety analysis, and its unit is the physical unit of the measured variable.

7. The control method of the reactor diversified signal protection system according to claim 6, characterized in that: After determining the offset, the signal setting value of the diversified protection system is expressed as follows: S DAS =S RPS / ESFAS ±σ (3) In the above formula, S DAS It is the signal setting value of the diversified protection system. "±" means adding (or subtracting) the deviation according to the situation. S RPS / ESFAS Signal setting value for the main protection system.

8. The control method of the reactor diversified signal protection system according to claim 6, characterized in that: The sensor portion is not taken into account when calculating the offset.

9. The control method of the reactor diversified signal protection system according to claim 5, characterized in that: In step 2, the sensor response time T1 of the main protection system and the diversified protection system is the same, and a certain delay link is considered for T2 of the diversified protection system: the protection action triggering time of the main protection system is T RT(RPS) / action(ESFAS) =T1+T 2(RPS / ESFAS) , the protection action triggering time of the diversified protection system is T RT / action(DAS) =T1+T 2(DAS) +T 2delay(DAS) ; In the above formula, T RT(RPS) / action(ESFAS) The main protection system action response time, T RT / action(DAS) Action response time for diversified protection systems; T1 is the sensor response time; T 2(RPS / ESFAS) The response time from the output of the main protection system sensor to the input of the trip circuit breaker or the response time from the output of the measuring sensor to the issuance of a dedicated trigger signal, T 2(DAS) Corresponding response times for diverse protection systems; T 2delay(DAS) Delay time set for the diversified protection system.

10. The control method of the reactor diversified signal protection system according to claim 9, characterized in that: When T 2(DAS) Less than T 2(RPS / ESFAS) In this case, the diversified protection signal is issued earlier than the main protection signal.

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