JPH09304575A - Regular inspection work aiding device for nuclear power station - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a regular inspection work aiding device capable of operating a plurality of control rods safely, efficiently in working and in the subcritical state. SOLUTION: By a work aiding computer 2, whether a control rod where surrounding 4 fuel assemblies are all taken out, exists or not, is judged. If there is such a control rod, a control rod position monitoring device 4 outputs an operation enabling signal (e) for a plurality of control rods to permit the withdrawal of the control rods to a control rod manual operation device 6. By this, an operator withdraws the particular control rods with the control rod manual operation device 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regular inspection work support device for a nuclear power plant for supporting fuel assembly replacement work during a regular inspection of a nuclear power plant.

[0002]

2. Description of the Related Art The core work of a nuclear reactor at the time of periodic inspection (at the time of regular inspection) of a nuclear power plant is carried out by an operator based on a predetermined operation procedure manual, an operation accompanying a movement work of a fuel assembly,
The control rod is pulled out and inserted, and the control rod drive mechanism is inspected.

During the periodic inspection of a nuclear power plant, when the reactor operation mode switch is in the "refueling mode",
Only one control rod can be pulled out, and two or more control rods cannot be pulled out at the same time.
That is, an interlock that prevents selection of the second one is provided on the control rod manual operation device side.
The subcriticality of the core is secured during the periodic inspection of the plant.
For this reason, the core work at the time of the periodic inspection is to be advanced for each control rod, which greatly affects the inspection period.

Further, in order to shorten the work time of the core work at the time of periodic inspection, it is possible to work by bypassing the interlock of all control rod full insertion signals provided on the side of the control rod manual operation device. Conceivable. In other words, it is a work in which it is permitted to pull out two or more control rods at the same time. When performing this work, the operator operates according to a predetermined procedure manual, and it is checked whether different operators are operating according to the procedure manual. I try to ensure criticality. Therefore, the burden on the operator for core work and plant condition monitoring is extremely large.

[0005]

As described above, the core work in the periodical inspection of the nuclear power plant is performed in a state in which the subcritical state is secured, and therefore, in general, it is possible to operate each control rod one by one. Since the work proceeded according to the procedure, the work efficiency was poor and the inspection period was greatly affected.

Further, in order to enable operation of a plurality of control rods, when operating by bypassing all control rod full insertion signal interlocks provided in the control rod manual operation device,
Since it is performed by the operator's judgment and operation, the burden on the operator is heavy and lacks reliability, and there are some concerns from the viewpoint of safety and management.

An object of the present invention is to provide a work support device during a regular inspection of a nuclear power plant which can safely and efficiently operate a plurality of control rods in a state where a subcritical state is secured.

[0008]

SUMMARY OF THE INVENTION The invention of claim 1 is a fuel exchanger computer for managing fuel assembly replacement work at the time of regular inspection of a nuclear power plant, and work for supporting the fuel assembly replacement work. A support computer, a control rod position monitoring device for permitting the withdrawal of one control rod under the condition that all control rods all insertion signals are satisfied at the time of fuel assembly replacement work, and withdrawal of the permitted control rods is performed. A work support device for a regular inspection of a nuclear power plant equipped with a control rod manual operation device, wherein the work support computer includes four control units around one control rod based on fuel assembly replacement work information from the fuel exchange computer. The control rod position monitoring device determines whether all the fuel assemblies of the book have been taken out, and when the determination conditions in the work support computer are satisfied, the control rod position monitoring device issues a control rod full insertion signal, which is a condition for pulling out the control rods. Scan and is obtained so as to output the operational signals of a plurality of control rods to control rod manual operation apparatus.

According to the first aspect of the present invention, when the work support computer determines that there is a control rod from which all four surrounding fuel assemblies have been taken out, the control rod position monitoring device pulls out the control rod. The control enable signal of the plurality of control rods is output to the control rod manual operation device in order to permit the above. This allows
The operator pulls out the corresponding control rod by the control rod manual operation device.

The invention according to claim 2 is such that, in the invention according to claim 1, when the fuel exchange computer or the work support computer fails, the output of the determination result in the work support computer is blocked.

According to the invention of claim 2, in addition to the operation of the invention of claim 1, a failure signal is input to the work support device by the refueling computer or the work support computer, and the control rod position monitoring device erroneously detects all the control rods. The determination result output from the work support computer is automatically blocked so as to bypass all control rod insertion signals and not output operable signals for a plurality of control rods.

[0012] The invention of claim 3 is claim 1 or claim 2.
In the invention described above, the control rod position monitoring device is provided with all control rod full insertion dummy switches for generating operable signals for a plurality of control rods.

According to the invention of claim 3, in addition to the operation of the invention of claim 1 or claim 2, the all-control-rod all-insertion simulation switch is used to bypass all the all-control-rod insertion signals to operate a plurality of control rods. Generate an operable signal that enables Even if the judgment result output from the work support computer is not normal when the refueling computer or work support computer fails,
It is possible to operate multiple control rods.

The invention according to claim 4 is the invention according to claims 1 to 3.
In the invention described above, the permission switch for permitting the determination result from the work support computer to be taken into the control rod position monitoring device is provided.

According to the invention of claim 4, in addition to the effects of the inventions of claims 1 to 3, only when the permission switch is ON, the determination result from the work support computer is fetched into the control rod position monitoring device, Bypass all control rod insertion signals except when necessary to prevent unnecessary generation of control rod operable signals.

According to a fifth aspect of the invention, in the invention of the fourth aspect, an alarm is issued when the permission switch is in the ON state and the reactor operation mode is other than the refueling mode. .

According to the fifth aspect of the present invention, when the reactor operation mode switch is set to a mode other than the refueling mode, that is, when the reactor start is started, an alarm is generated if the permission switch remains ON. And prevent forgetting to release the permission switch.

[0018]

Embodiments of the present invention will be described below. FIG. 1 is a configuration diagram showing an embodiment of the present invention. The fuel exchange computer 1 manages the fuel assembly replacement work at the time of regular inspection of the nuclear power plant, and manages the movement information of the fuel assembly of the reactor core as the fuel assembly replacement work information. The movement information a of the fuel assembly (hereinafter referred to as fuel movement information) a is input to the work support computer 2. Further, the failure signal b of the fuel exchange computer 1 is also input to the work support computer 2.

The work support computer 2 has a predetermined control rod and fuel assembly position information as a fuel map 3. The fuel transfer information a of the core is input from the fuel exchanger computer, and fuel assembly is always performed. It monitors the loading status of the body. Then, the fuel movement information a from the fuel exchange computer 1 and the information on the fuel map 3 are compared to determine whether or not all the fuel assemblies around one control rod have been taken out.

This is because the cell (combination of one control rod and four surrounding fuel assemblies) in a state where all four fuel assemblies around one control rod are taken out is controlled. This is because there is no effect due to the position of the rod, and it can be treated as a cell that is not considered to be the core. From this, from the fuel movement information a which is the fuel assembly replacement work information from the fuel exchange computer 1, the cells that are not regarded as the core are automatically determined.

When there is a control rod from which all the surrounding fuel assemblies have been taken out, the work support computer 2 judges that the control rod can be pulled out, and determines the control rod position monitor 4.
The result of the navel judgment is output. That is, a masking command signal c for masking the pull-out prohibition condition of the control rod.
Is output.

The control rod monitoring control device 4 is provided with an interlock circuit 5 corresponding to each of a plurality of control rods. Each interlock circuit 5 receives all the control rods by the masking command signal c. The output of the interlock circuit 5 is forcibly established regardless of whether or not the insertion signal d is established. As a result, an operation permission signal for enabling the pulling operation of the control rod is output. That is, the withdrawal prohibition condition is bypassed, and a withdrawal permission signal is output to the control rod manual operation device 6 to enable a plurality of control rod operations at the time of regular inspection.

That is, the control rod position monitoring device 4 has the interlock circuit 5 for permitting the pulling out of the control rods in units of control rods, and during normal regular inspection, only one control rod can be operated. The condition is satisfied. First, in the state before the pull-out operation of the control rods, all the control rods are fully inserted, so that the all-control-rods all-insertion signal d is established. Therefore, the output signal of each interlock circuit 5 is established and A
The output of the ND circuit 7 is established. From this, the control rod manual operation device 6 outputs a control rod operation enable signal (all control rods all insertion signal) e which enables the control rods to be operated,
The control rod can be pulled out.

When one control rod is pulled out, all the control rods are not in the fully inserted state, so that all the control rods all insertion signals d are not established, and the interlock circuit 5 provided for each control rod is All are unsuccessful. This prohibits pulling out one or more control rods.

On the other hand, when the above-mentioned masking signal c is output and the permission switch 8 to be described later is in the ON state, the interlock circuit 5 bypasses all control rod all insertion signals d. The control rod manual operation device 6 outputs a control rod operable signal (all control rod all insertion signals) e. Therefore, it is possible to pull out a plurality of control rods. In this way, the work support computer 2 makes it possible to perform the pull-out operation of the control rods for all the control rods for which the cells that are not considered to be the core are determined.

Next, the fuel exchange computer 1 outputs a failure signal b of the fuel exchange computer 1 to the work support computer 2. When this failure signal b occurs, the work support is considered in consideration of the safety of the work. The computer 2 determines that the core is not considered to be the core, and resets all the masking signals c output to the control rod position monitoring device 4. Further, when the work support computer 2 fails, an interlock is made so that the masking signal c is not output in advance, so that safety measures can be taken as with the fuel exchange computer 1.

If the refueling computer 1 or the work support computer 2 fails, the masking signal c output to the control position monitoring device 4 will be lost.
As a result, the interlock circuit 5 in the control rod position monitoring device 4 may fail. In that case, the control rod operation permission signal (all control rod all insertion signal) e, which is the control rod operation permission condition for the control rod manual operation device 6, is lost, and the control dedicated manual operation device 6 cannot operate at all. Become.

In the unlikely event that the refueling computer 1 or the work support computer 2 breaks down, the control rods can be operated (insertion operation in this case), so that all the control rods are inserted into the control position monitoring device 4. A simulated switch 9 is provided. By operating this control rod full insertion simulation switch 9, the control rod manual operation device 6 is controlled by forcibly bypassing all the control rod full insertion signals d of the interlock circuit 5 in the control rod position monitoring device 4. The rod operation permission signal (all control rod insertion signals) e is established, and the control rods can be operated.

An interlock circuit 5 by all control rod full insertion simulation switches 9 provided in the control rod position monitoring device 4.
The bypass of all the control rod all insertion signals d in (1) may be established by ANDing with the failure signal b of the fuel exchange computer 1 or the work support computer 2. In such a case, erroneous operation can be prevented.

Next, the permission switch 8 sets a permission condition for preventing the bypass by the masking signal c from the work support computer 2 from being bypassed other than necessary. When the permitting condition is satisfied by operating the permitting switch 8, the interlock circuit 5 in the control rod position monitoring device 4 causes the interlocking circuit 5 in the control rod position monitoring device 4 to insert all the control rods into all the signals when the permitting conditions are satisfied. The bypass condition of d is satisfied. The permission switch 8 is effectively a switch with a key in view of prevention of erroneous operation.

Further, the reactor operation mode switch 10 is
It is installed in the reactor control panel 11 that controls the reactor, and the operating mode of the reactor operation mode switch 10 causes the reactor to operate in any one of stop, refuel, start, and operation modes. It is in. When there is a fuel assembly replacement work during the periodic inspection of the nuclear power plant, the fuel replacement position is selected for the reactor operation mode switch 10.
When the periodic inspection is completed and the nuclear reactor is operated, the nuclear reactor operation mode switch 10 is selected in the order of the refueling position, the starting position, and the operating position.

In order to prevent forgetting to return the permission switch 8 during the operation of the reactor, the condition for establishing the permission switch 8 and the condition for starting or operating the reactor operation mode switch 10 are ANDed. Alarm device 1 depending on conditions
2 is configured to generate an alarm. With this alarm, even when the operator forgets to return the permission switch 8 when operating the nuclear reactor, clear information can be provided to the operator.

[0033]

As described above, according to the present invention, the work support computer determines the cells that are not considered to be the core by the movement information of the fuel assembly from the fuel exchange computer, and when the determination condition is satisfied. Outputs an operation permission signal to the control rod manual operation device so that a plurality of control rods can be operated at the same time, thus reducing the burden on the operator. Further, since the inspection accompanying the control rod operation can be performed in parallel, the inspection period can be shortened.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

[Explanation of symbols]

 1 Fuel exchange computer 2 Work support computer 3 Fuel map 4 Control rod position monitoring device 5 Interlock circuit 6 Control rod manual operation device 7 AND circuit 8 Permit switch 9 All control rod full insertion simulation switch 10 Reactor operation mode switch 11 Atom Furnace control panel 12 alarm

Claims (5)

[Claims] 1. A refueling computer for managing fuel assembly replacement work during a regular inspection of a nuclear power plant,
A work support computer for supporting the fuel assembly replacement work, and a control rod position monitoring for permitting the withdrawal of one control rod under the condition that all control rod all insertion signals are satisfied during the fuel assembly replacement work. In a regular inspection work support device for a nuclear power plant equipped with a device and a control rod manual operation device for performing a permitted control rod withdrawal operation, the work support computer is a fuel assembly replacement work from the fuel exchange computer. Based on the information, it is determined whether or not all four fuel assemblies around one control rod have been taken out, and the control rod position monitoring device performs control when the determination condition in the work support computer is satisfied. A constant of a nuclear power plant characterized in that all control rod insertion signals, which are rod withdrawing conditions, are bypassed and a plurality of control rod operable signals are output to the control rod manual operation device. When the work support apparatus. 2. The nuclear power plant according to claim 1, wherein when the refueling computer or the work support computer fails, the output of the determination result by the work support computer is blocked. Regular inspection work support device. 3. The control rod position monitoring device is provided with all control rod full insertion simulation switches for generating operable signals of the plurality of control rods. The work support device during regular inspection of the nuclear power plant described in. 4. The nuclear power plant according to claim 1, further comprising a permission switch for permitting the determination result from the work support computer to be taken into the control rod position monitoring device. Regular inspection work support device. 5. The nuclear power plant according to claim 4, wherein an alarm is generated when the permission switch is ON and the reactor operation mode is other than the refueling mode. Regular inspection work support device.