Power supply circuit of nuclear measurement instrument

Abstract

The invention relates to the technical field of high-temperature gas cooled reactor power supply, and discloses a power supply circuit of a nuclear measurement instrument, which is characterized in that under the condition of daily operation, during maintenance, a power distribution branch is disconnected, each normal power distribution branch is closed, and each normal power distribution branch supplies power to the corresponding nuclear measurement instrument after taking power from a corresponding reactor power supply sequence; during the maintenance period, each normal power distribution branch is closed, the power distribution branches take power from the reactor in the maintenance state after being conducted during the maintenance period, and the power distribution branches only supply power to the nuclear measurement instrument of the reactor in the maintenance state during the maintenance period. A standby power supply is added by adding a power supply loop, and can be used for power supply in daily and overhaul periods under the condition that an upstream power supply loses power, the condition that a nuclear measurement monitoring instrument is unavailable is avoided, the power supply reliability is improved, meanwhile, resource waste caused by laying of a temporary power supply loop in the overhaul period is reduced, and the maintenance cost is reduced. And the method is implemented in a high-temperature reactor, and the effect is good.

Description

Technical Field

[0001] The invention relates to the technical field of high temperature gas-cooled reactor power supply, and in particular to a power supply circuit for a nuclear measuring instrument. Background Art

[0002] A high-temperature gas-cooled reactor consists of two nuclear steam supply systems connected to a steam turbine to form a nuclear power unit. Each reactor is equipped with an independent nuclear measurement system. The functions, structures and configurations of the two nuclear measurement systems are exactly the same and are implemented using the same equipment.

[0003] The neutron fluence rate level and its change rate monitoring of high temperature gas-cooled reactors adopts a "three-stage" measurement scheme. The nuclear measurement system includes three neutron systems: source range subsystem, intermediate range subsystem and power range subsystem. In order to meet different neutron fluence rate monitoring ranges and corresponding pulse count rate ranges, different detectors are used in the three neutron systems.

[0004] According to the design requirements, the nuclear measurement system should provide the protection system, DCS system and main control room with information such as nuclear power value, multiple period, voltage detection value, device bypass and device failure. All connection signals outside the nuclear measurement instrument cabinet should be isolated in this cabinet to ensure the electrical independence of the nuclear measurement instrument cabinet. Because the measurement cabinets of the nuclear measurement system are distributed in multiple locations on the 7 floors above and below the reactor, for the convenience of maintenance, they are powered by the instrument distribution box near the cabinet installation location. The safety bus uses the 0m instrument distribution box to centrally supply power to all instrument distribution boxes above and below the reactor in a branched manner.

[0005] The nuclear measurement system monitors the neutron injection rate of the reactor from shutdown to rated power, and all system functions are safety functions. Therefore, even during shutdown, the nuclear measurement system is required to be put into normal operation to monitor the reactor status, and the longest power outage time cannot exceed 2 hours. However, during overhaul, the upstream power distribution section is shut down in batches for pre-maintenance, which will cause the nuclear measurement system instruments to lose power and shut down. In general, temporary power is connected to power such equipment, but temporary cables need to be laid, which requires a large amount of on-site work. In addition, the relevant equipment must be dismantled after each overhaul, which also leads to waste of materials. Summary of the invention

[0006] In view of this, the present invention provides a power supply circuit for a nuclear testing instrument to solve the problem of temporary power supply when the normal power supply of the nuclear testing monitoring instrument fails during overhaul.

[0007] The present invention provides a power supply circuit for a nuclear measuring instrument. A high temperature gas-cooled reactor comprises a plurality of sets of nuclear measuring instruments, a plurality of reactor power supply sequences and a plurality of reactors. A set of nuclear measuring instruments is used to measure the state of a reactor. A reactor power supply sequence supplies power to a reactor. The power supply circuit comprises: a plurality of normal power distribution branches and power distribution branches during maintenance. The input end of each normal power distribution branch is connected to a first safety busbar of a reactor power supply sequence of a high temperature gas-cooled reactor, and the output end of each normal power distribution branch is connected to a set of nuclear measuring instruments of the high temperature gas-cooled reactor; the power distribution branch during maintenance The input end is connected to the second safety busbar of each reactor power supply sequence, and the output end of the distribution branch is connected to each set of nuclear measurement instruments during maintenance; in daily operation, the distribution branch is disconnected during maintenance and each normal distribution branch is closed, and each normal distribution branch draws power from the corresponding reactor power supply sequence to supply power to the corresponding nuclear measurement instrument; during maintenance, each normal distribution branch is closed, and the distribution branch is turned on during maintenance and draws power from the reactor that is under maintenance, and during maintenance, the distribution branch only supplies power to the nuclear measurement instruments of the reactor that is under maintenance.

[0008] The present invention adds a backup power supply by adding a power supply circuit, which can be used for power supply in the event of power failure of the upstream power supply during daily and overhaul periods, avoiding the unavailability of nuclear measurement and monitoring instruments, increasing the power supply reliability, and reducing the waste of resources caused by laying temporary power supply circuits during overhauls, thereby improving work efficiency. The present invention has been implemented in high-temperature reactors with good results.

[0009] In an optional embodiment, a normal power distribution branch includes: a first switch module and a second switch module, wherein the input end of the first switch module is connected to the first safety bus of a reactor power supply sequence of a high-temperature gas-cooled reactor, and the output end of the first switch module is connected to the input end of the second switch module; the output end of the second switch module is connected to a set of nuclear measurement instruments of the high-temperature gas-cooled reactor; in daily operation, the first switch module and the second switch module are both closed; during maintenance, the first switch module and the second switch module are both disconnected.

[0010] In an optional implementation, the first switch module is a first circuit breaker.

[0011] In an optional implementation, the second switch module includes: an isolating switch.

[0012] In an optional embodiment, the power distribution branch during maintenance includes: multiple third switch modules and fourth switch modules, wherein the input end of each third switch module is connected to the second bus of a reactor power supply sequence, and the output end of each third switch module is connected to an input end of the fourth switch module; the output end of the fourth switch module is connected to each set of nuclear measurement instruments; under daily operation, each third switch module and fourth switch module are disconnected; during maintenance, the third switch module connected to the reactor under maintenance is closed, and the fourth switch module only connects the third switch module connected to the reactor under maintenance to the nuclear measurement instruments of the reactor under maintenance.

[0013] In an optional implementation, the third switch module includes: a second circuit breaker.

[0014] In an optional implementation, the second switch module is placed in a distribution box of the 0-meter nuclear measuring instrument.

[0015] In an optional embodiment, all the second circuit breakers are interlocked to ensure that only the nuclear measuring instruments of the reactor under maintenance are powered during maintenance.

[0016] In an optional embodiment, the fourth switch module includes: a power switching switch and a load selector, wherein each input end of the power switching switch is connected to an output end of a third switch module, and the output end of the power switching switch is connected to the input end of the load selector; each output end of the load selector is connected to a nuclear measurement instrument of a reactor.

[0017] In an optional embodiment, the high temperature gas-cooled reactor has only two reactors, and the power supply circuit has only two normal distribution branches and one distribution branch during maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a schematic diagram of the structure of a high temperature gas-cooled reactor;

[0020] Figure 2 is a structural schematic diagram of a power supply circuit of a nuclear testing instrument according to an embodiment of the present invention;

[0021] Figure 3 is a structural schematic diagram of a power supply circuit of another nuclear testing instrument according to an embodiment of the present invention;

[0022] Figure 4 is a structural schematic diagram of a power supply circuit of another nuclear testing instrument according to an embodiment of the present invention;

[0023] Figure 5 is a structural schematic diagram of a power supply circuit of another nuclear testing instrument according to an embodiment of the present invention;

[0024] Figure 6 Detailed description is a schematic structural diagram of an example of a power supply circuit of another nuclear testing instrument according to an embodiment of the present invention. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 those skilled in the art without creative work are within the scope of protection of the present invention.

[0026] In this embodiment, a power supply circuit of a nuclear test instrument is provided, such as Figure 1 As shown, the high temperature gas-cooled reactor includes multiple sets of nuclear measuring instruments, multiple reactor power supply sequences and multiple reactors. One set of nuclear measuring instruments is used to measure the status of a reactor, and one reactor power supply sequence supplies power to one reactor.

[0027] like Figure 2 As shown, the power supply circuit of the nuclear test instrument includes: multiple normal distribution branches and distribution branches during maintenance, Figure 2 Taking the high temperature gas-cooled reactor including two reactors as an example, each reactor has a corresponding reactor power supply sequence and nuclear measurement instrument. The power supply circuit of the nuclear measurement instrument includes two normal distribution branches and one distribution branch during maintenance.

[0028] like Figure 2 As shown, the input end of each normal distribution branch is connected to the first safety busbar of a reactor power supply sequence of the high-temperature gas-cooled reactor, and the output end of each normal distribution branch is connected to a set of nuclear measurement instruments of the high-temperature gas-cooled reactor; the input end of the distribution branch during maintenance is connected to the second safety busbar of each reactor power supply sequence, and the output end of the distribution branch during maintenance is connected to each set of nuclear measurement instruments.

[0029] Specifically, a power distribution branch during maintenance is added on the basis of the normal power supply of the nuclear measurement system detection instruments, which is used for temporary power supply when the normal power supply of the nuclear measurement monitoring instruments is lost during overhaul. Among them, circuit breaker electrical interlocks, isolating switches, transfer switches, load selectors and other equipment are set in the relevant circuits to ensure the power supply independence of the nuclear measurement systems of the two reactors and the personal safety of maintenance personnel under normal circumstances.

[0030] Specifically, for different situations during daily operation and maintenance, the operation of the power supply circuit is as follows:

[0031] (1) During routine operation, the distribution branch is disconnected during maintenance and each normal distribution branch is closed. Each normal distribution branch draws power from the corresponding reactor power supply sequence to supply power to the corresponding nuclear measurement instruments.

[0032] (2) During the maintenance period, each normal distribution branch is closed. After the distribution branch is turned on during the maintenance period, it draws power from the reactor that is under maintenance. During the maintenance period, the distribution branch only supplies power to the nuclear measurement instruments of the reactor that is under maintenance.

[0033] For example, Figure 2 For example, there are two reactors, namely reactor #1 and reactor #2. Reactor power supply sequence #1 supplies power to reactor #1 and nuclear measurement instrument #1, and reactor power supply sequence #2 supplies power to reactor #2 and nuclear measurement instrument #2. Reactor power supply sequence #1 has the first safety bus #1 and the second safety bus #1, and reactor power supply sequence #2 has the first safety bus #2 and the second safety bus #2.

[0034] Exemplarily, during daily operation, the normal distribution branch #1 draws power from the first safety bus #1, and the normal distribution branch #2 draws power from the first safety bus #2, and the normal distribution branch #1 and the normal distribution branch #2 are closed, and the distribution branch is disconnected during maintenance. At this time, the conduction of the normal distribution branch #1 establishes the connection between the first safety bus #1 and the nuclear measuring instrument #1, and the conduction of the normal distribution branch #2 establishes the connection between the first safety bus #2 and the nuclear measuring instrument #2. The first safety bus #1 supplies power to the nuclear measuring instrument #1, and the first safety bus #2 supplies power to the nuclear measuring instrument #2.

[0035] For example, during maintenance, when reactor #1 is under maintenance, the normal distribution branch #1 is disconnected. During maintenance, the distribution branch draws power from the second safety bus #1 to supply power to the nuclear measuring instrument #1, while the normal distribution branch #2 draws power from the first safety bus #2 to supply power to the nuclear measuring instrument #2.

[0036] Optionally, the first safety busbar and the second safety busbar can also serve as backup for each other. For example, when the first safety busbar is normal, the first safety busbar supplies power to the nuclear measuring instruments through the normal distribution branch. When the first safety busbar fails, the second safety busbar supplies power to the nuclear measuring instruments through the distribution branch during maintenance.

[0037] In some optional embodiments, Figure 2 For example, Figure 3 As shown, the normal power distribution branch includes: a first switch module and a second switch module. The input end of the first switch module is connected to the first safety busbar of a reactor power supply sequence of the high temperature gas-cooled reactor, and the output end of the first switch module is connected to the input end of the second switch module; the output end of the second switch module is connected to a set of nuclear measurement instruments of the high temperature gas-cooled reactor; in the case of daily operation, the first switch module and the second switch module are both closed; during maintenance, the first switch module and the second switch module are both disconnected.

[0038] For example, Figure 2 In the routine operation, the first switch module #1, the second switch module #1, the first switch module #2, and the second switch module #2 are all closed, the first safety bus #1 supplies power to the nuclear instrument #1, and the first safety bus #2 supplies power to the nuclear instrument #2. When the reactor #1 is repaired and the reactor 2 is operating normally, the first switch module #1 and the second switch module #1 are disconnected, and during the maintenance period, the distribution branch draws power from the second safety bus #1 to supply power to the nuclear instrument #1, while the first switch module #2 and the second switch module #2 are closed, and the first safety bus #2 supplies power to the nuclear instrument #2.

[0039] In some optional embodiments, the first switch module is a first circuit breaker.

[0040] In some optional implementations, the second switch module includes: an isolating switch. The isolating switch can achieve electrical isolation between the safety bus and the nuclear test instrument.

[0041] In some optional embodiments, the second switch module is placed in the distribution box of the 0-meter nuclear measurement instrument.

[0042] In some optional embodiments, Figure 2 For example, Figure 3 As shown, the power distribution branch during maintenance includes: a plurality of third switch modules and a fourth switch module.

[0043] like Figure 3As shown, the input end of each third switch module is connected to the second bus of a reactor power supply sequence, and the output end of each third switch module is connected to an input end of the fourth switch module; the output end of the fourth switch module is connected to each set of nuclear measurement instruments; in daily operation, each third switch module and the fourth switch module are disconnected.

[0044] Specifically, during maintenance, the third switch module connected to the reactor under maintenance is closed, and the fourth switch module only connects the third switch module connected to the reactor under maintenance to the nuclear measuring instruments of the reactor under maintenance.

[0045] For example, Figure 4 When reactor #1 is under maintenance and reactor #2 is operating normally, the first switch module #1, the second switch module #1 and the third switch module #2 are disconnected, and the third switch module #1, the first switch module #2 and the second switch module #2 are closed. The second safety bus #1 supplies power to the nuclear measuring instrument #1, and the first safety bus #2 supplies power to the nuclear measuring instrument #2.

[0046] In some optional embodiments, the third switch module includes: a second circuit breaker.

[0047] In some optional embodiments, all second circuit breakers are interlocked to ensure that only the nuclear instrumentation of the reactor under maintenance is powered during maintenance. An electrical interlock is set between the two circuit breakers to ensure that only one circuit breaker can be closed at the same time.

[0048] In some optional embodiments, such as Figure 5 As shown, the fourth switch module includes: a power switching switch and a load selector, wherein each input end of the power switching switch is connected to an output end of the third switch module, and the output end of the power switching switch is connected to the input end of the load selector; each output end of the load selector is connected to a nuclear measurement instrument of a reactor.

[0049] Specifically, after the third switch module is closed, the power switching switch is used to connect the closed third switch module to the load selector, and the load selector is used to transmit the voltage of the second safety bus to the corresponding nuclear measurement instrument.

[0050] In some optional embodiments, the high temperature gas-cooled reactor has only two reactors, and the power supply circuit has only two normal distribution branches and one distribution branch during maintenance.

[0051] Figure 6The structural diagram is an example of the power supply circuit of the nuclear measuring instrument. Two distribution sections with higher safety levels and their circuit breakers are selected from the distribution section that is different from the normal power supply as the power supply circuit breakers during the instrument overhaul; an electrical interlock is set between the two circuit breakers to ensure that only one circuit breaker can be closed at the same time; a nuclear measurement system monitoring instrument overhaul power supply switching box is set in the public area between the two reactors, and a power supply switching switch and a load selector are installed inside; the output cables of the power supply circuit breakers during the overhaul of the two instruments are connected to the power supply switching switch, and the common end of the power supply switching switch is connected to the common end of the load selector through a cable. The load selector has four positions, and the two positions near the two sides are connected to the 0m instrument distribution boxes of the two reactors respectively to provide them with backup power supply; 5. A normal power supply isolation switch is added between the lower port of the normal power supply circuit breaker of the instrument and the instrument distribution box, and is placed in the 0m instrument distribution box of the two reactors.

[0052] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A power supply circuit for a nuclear testing instrument, characterized in that: The high temperature gas-cooled reactor comprises a plurality of sets of the nuclear measuring instruments, a plurality of reactor power supply sequences and a plurality of reactors, wherein a set of the nuclear measuring instruments is used to measure the state of a reactor, a reactor power supply sequence supplies power to a reactor, and the power supply circuit comprises: a plurality of normal power distribution branches and power distribution branches during maintenance, wherein: The input end of each of the normal power distribution branches is connected to the first safety busbar of a reactor power supply sequence of the high temperature gas-cooled reactor, and the output end of each of the normal power distribution branches is connected to a set of nuclear measurement instruments of the high temperature gas-cooled reactor; The input end of the power distribution branch during maintenance is connected to the second safety busbar of each reactor power supply sequence, and the output end of the power distribution branch during maintenance is connected to each set of nuclear measurement instruments; In the case of daily operation, the power distribution branch is disconnected during the maintenance period, and each of the normal power distribution branches is closed. Each of the normal power distribution branches takes power from the corresponding reactor power supply sequence to supply power to the corresponding nuclear measurement instrument; During maintenance, each of the normal power distribution branches is closed, and the power distribution branches during maintenance are turned on to draw power from the reactor that is under maintenance, and the power distribution branches during maintenance only supply power to the nuclear measurement instruments of the reactor that is under maintenance.

2. The power supply circuit of the nuclear test instrument according to claim 1, characterized in that: The normal power distribution branch includes: a first switch module and a second switch module, wherein: The input end of the first switch module is connected to a first safety busbar of a reactor power supply sequence of a high temperature gas-cooled reactor, and the output end of the first switch module is connected to the input end of the second switch module; The output end of the second switch module is connected to a set of nuclear measurement instruments of the high temperature gas-cooled reactor; In the case of daily operation, the first switch module and the second switch module are both closed; During maintenance, the first switch module and the second switch module are both disconnected.

3. The power supply circuit of the nuclear test instrument according to claim 2, characterized in that: The first switch module is a first circuit breaker.

4. The power supply circuit of the nuclear test instrument according to claim 2, characterized in that: The second switch module includes: an isolating switch.

5. The power supply circuit of the nuclear test instrument according to claim 5, characterized in that: The second switch module is placed in the distribution box of the 0-meter nuclear measuring instrument.

6. The power supply circuit of the nuclear test instrument according to claim 1, characterized in that: The power distribution branch during maintenance includes: a plurality of third switch modules and a fourth switch module, wherein: The input end of each of the third switch modules is connected to a second busbar of a reactor power supply sequence, and the output end of each of the third switch modules is connected to an input end of the fourth switch module; The output end of the fourth switch module is connected to each set of nuclear testing instruments; In the case of daily operation, each of the third switch module and the fourth switch module is disconnected; During maintenance, the third switch module connected to the reactor under maintenance is closed, and the fourth switch module only connects the third switch module connected to the reactor under maintenance to the nuclear measurement instruments of the reactor under maintenance.

7. The power supply circuit of the nuclear test instrument according to claim 6, characterized in that: The third switch module includes: a second circuit breaker.

8. The power supply circuit of the nuclear test instrument according to claim 7, characterized in that: Also includes: All second circuit breakers are interlocked to ensure that only the nuclear measuring instruments of the reactor under maintenance are powered during maintenance.

9. The power supply circuit of the nuclear test instrument according to claim 6, characterized in that: The fourth switch module includes: a power switch and a load selector, wherein: Each input end of the power switch is connected to an output end of the third switch module, and the output end of the power switch is connected to the input end of the load selector; Each output end of the load selector is connected to a nuclear measuring instrument of a reactor.

10. The power supply circuit of the nuclear test instrument according to any one of claims 1 to 9, characterized in that: The high temperature gas-cooled reactor has only two reactors, and the power supply circuit has only two normal distribution branches and one distribution branch during maintenance.

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