JPH0333697A - Monitoring device for reactor core - Google Patents

Abstract

PURPOSE:To detect a human error in advance and to enable its protection by converting an analogue signal transmitted from a TV camera into a digital one and by conducting an image processing of the converted signal by a computer. CONSTITUTION:An analogue signal being output from a freely movable TV camera 1 arranged right above a reactor core 2, is fed to an image processing computer 4 through an A/D converter 3. A fuel information obtained by the computer 4, and a loading schedule information of a co-ordinates by which a next fuel is to be loaded into the reactor core by an automatic refuelling machine system 6, are compared by a comparator 8. Then, when a fuel is al ready loaded at co-ordinates where the next fuel is to be loaded, a signal to halt the automatic refuelling machine forcedly is sent to the refuelling machine system 6, and concurrently the reason to halt the machine is displayed on a CRT 5. In case that even one fuel remains around a control rod to be operated, a signal to intercept a control rod operation is sent to a control rod controlling system 7. At the same time, the reason to intercept the operation is displayed on the CRT 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a reactor core monitoring device used during periodic inspections of nuclear power plants.

(Conventional technology) Fuel replacement work during periodic inspections involves moving the fuel arrangement or replacing it with new fuel by controlling burnup, etc., but in conjunction with this, control rod replacement work is also required. included. In order to carry out these operations safely and efficiently, humans must consider the work steps in advance, such as automatic fuel exchange machines and automatic control rod exchange machines.
There are systems in which tasks are automatically executed by programming a computer.

(Problem to be solved by the invention) Although the above-mentioned system is very convenient, if there is even one mistake in loading the computer, fuel may be loaded in the wrong place or the wrong control rod may be pulled out. Unfavorable for core management. Therefore, it is an object of the present invention to detect human errors in advance and take preventative measures.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, in the present invention, a movable television camera is installed above the reactor core, and analog signals transmitted from the television camera are converted from analog to digital. This converted signal is image-processed by a computer to calculate fuel loading information for all core coordinates.
Next, a comparator compares the fuel loading information on the core coordinates to be loaded with the loading schedule information in the refueling machine computer, and if they are different, the comparator sends a stop signal to forcibly stop the refueling machine, and at the same time the operator To provide a reactor core monitoring device characterized in that it transmits an alarm and an alarm signal indicating the status on a CRT.

(Function) In advance, three cases are registered in the activation processing computer: fuel loaded state, unloaded state, and double blade guide loaded state that is loaded in place of fuel to prevent control rods from collapsing after fuel is removed from the reactor core. Then, the status of all coordinates inside the furnace is grasped using pattern recognition method. This information is compared with the information on which coordinates in the reactor core should be loaded next to the automatic fuel exchange machine's calculator, and if there is a discrepancy, the automatic fuel exchange machine is forced to stop 3- At the same time, an alarm and information on the discrepancy is sent to the operator. Provided by CRT. In addition, when an operator attempts to withdraw a control rod, if the information on the fuel insertion state around the control rod coordinates indicates that at least one rod is loaded, a signal is sent to the control rod to prevent the control rod from being withdrawn. Provides a function to send to the circuit.

(Example) An example of the present invention will be described below with reference to the drawings.

In FIGS. 1 and 2, an analog signal output from a television camera 1 movably disposed directly above a reactor core 2 is input as a digital signal to an image processing computer 4 via an analog-to-digital converter 3. be done. By this input signal, the state of each coordinate of the core 2 is confirmed as shown in FIG. From this confirmation information, from (a) in Figure 4 (
As in g), (a) only double blade guide, (b) 1 fuel, (C) 2 fuels, (d) 2 fuels,
(e) 3 fuels, (f) 4 fuels, and (g) recognized as fuel heat.

In addition, in FIGS. 3 and 4, the reference numeral 10 indicates the fuel 4. , numeral 11 indicates a double blade guide.

Then, the comparator 8 compares the fuel information obtained by the image processing computer 4 with the loading schedule information of the coordinates of the automatic fuel exchanger system 6 to be loaded (or moved) into the reactor core next.

If the fuel 10 is already loaded at the coordinates to be loaded (or moved) next, a signal is sent to the automatic fuel exchange system 6 to forcibly stop the automatic fuel exchange machine. At the same time, CRT
5 displays the reason for the stop. Furthermore, when an operator attempts to operate a control rod using the control rod drive control system 7, the comparator 8 compares the signal of the control rod coordinates with the signal of the loaded or unloaded state of the fuel 10 around the control rod. If there is even one fuel 10 around the control rod to be operated, a signal is sent to the control rod drive control system 7 to stop the control rod operation. At the same time, the reason for cancellation is displayed on the CRT 5.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to prevent erroneous fuel loading, erroneous movement, or erroneous operation of control rods due to human error during periodic inspections, thereby further improving core safety management.

[Brief explanation of drawings]

Fig. 3 is a block diagram of a core monitoring device according to an embodiment of the present invention, Fig. 2 is an explanatory diagram showing the arrangement of the television cameras shown in Fig. 1, and Fig. 3 is an image of the arrangement shown in Fig. 1. An explanatory diagram showing the state of the reactor core confirmed by the processing computer, and FIGS. 4(a) to 4(g) are explanatory diagrams showing each fuel loading authorization side. 1...TV camera 2...Reactor core 3...Analog-to-digital converter 4...Image processing computer 5...CRT6...Automatic fuel exchanger system 7...Control rod drive control system 8... Comparator 10...Fuel 11...Double blade guide

Claims (1)

[Claims] A movable television camera is installed above the reactor core, and the analog signal sent from this television camera is converted into digital data via an analog-to-digital converter, and this converted signal is image-processed by a computer to determine the fuel in all core coordinates. Loading information is calculated, and then a comparator compares the fuel loading information on the core coordinates to be loaded with the loading schedule information in the fuel exchanger computer, and if they are different, a stop signal is sent from this comparator to forcibly stop the fuel exchanger. A reactor core monitoring system characterized in that it simultaneously transmits an alarm to an operator and an alarm signal indicating the status on a CRT.