JPH0389197A - Neutron flux monitor apparatus of nuclear of nuclear reactor - Google Patents

Abstract

PURPOSE:To achieve the enhancement of noise resistance and the reduction of the number of cables and to simultaneously measure high response and an average change by applying filtering processing to the output signal of each neutron detector and successively selecting the same to digitally converting the same. CONSTITUTION:The output of a nuclear reactor during operation is monitored upon the reception of the respective output signals from a plurality of the neutron detectors 1(1-1 - 1-n) arranged in a reactor core. At this time, the output signals of the detectors are respectively subjected to filtering processing by the first filter circuits 5 (5-1 - 5-n) to remove noise and successively selected by a signal selection means 6 to be digitally converted by an A/D converter 13. These signals are serially transmit ted by a transmission means 14 and reproduced at a speed same to or more than that of the means 6 by a high speed signal reproducing means 18 to be enhanced in response and the neutron flux in the reactor core is monitored by an operational monitor apparatus 22. At the same time, the signals are subjected to filtering processing by the second filter circuit 23 in an average value calculation means 19 and the average value of outputs is calculated by an operational monitor apparatus 24.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention provides a reactor neutron flux monitoring device that monitors the reactor output during power operation by receiving output signals from each neutron detector. Regarding.

(Prior Art) FIG. 5 is a block diagram of a nuclear reactor neutron flux monitoring device. Neutron detectors 1-1 to 1-n are arranged in the reactor core, and these neutron detectors 1-1 to 1-n are connected to analog signal processing devices 2-1 to 2-n and each cable 3-n, respectively. 1
3-n to an arithmetic and monitoring device 4 provided in the central control room. In addition, each analog signal processing device 2
-1 to 2-n may be arranged on the central control room side. As a result, the output signals of each of the neutron detectors 1-1 to 1-n are processed by the analog signal processing devices 2-1 to 2-n, respectively, and sent to the calculation and monitoring device 4. Determine and monitor the reactor output from the output signal.

However, in such a configuration, each cable 31 to 3-n
Since a minute analog current flows through the cables 3-1 to 3-n, it is necessary to use special cables with excellent noise resistance. For this reason, a method is adopted in which the output signals of each of the neutron detectors 1-1 to 1-n are transmitted to the arithmetic and monitoring device 4 using a single cable with excellent noise resistance.

By the way, in the measurement of neutrons in a nuclear reactor, high responsiveness is required to accurately reproduce each output signal of each neutron detector 1-1 to 1-n in the arithmetic and monitoring device 4, and at the same time, in order to obtain the reactor core performance. It is required to measure the average change in the output signal. However, in order to satisfy each of these requirements, the filter time constants in the arithmetic and monitoring device 4 must be set to contradictory values.
-n output signal is transmitted through an optical cable to the arithmetic monitoring device 4.
It is difficult to measure both high responsiveness and average change at the same time by processing only with .

(Problem to be Solved by the Invention) As described above, it is difficult to simultaneously measure high responsiveness and average changes that accurately reproduce each output signal of each neutron detector 1-1 to l-n. be.

Therefore, the present invention has developed a nuclear reactor neutron flux monitoring device that has excellent noise resistance, can reduce the number of cables, and can simultaneously measure average changes and high responsiveness that reproduces the output signal of a neutron detector with high accuracy. The purpose is to provide

[Structure of the Invention] (Means for Solving the Problems) The present invention provides an atomic system that monitors the output of a nuclear reactor during power operation by receiving output signals from a plurality of neutron detectors arranged in a nuclear reactor core. In the reactor neutron flux monitoring device, each first filter circuit performs filtering processing on the output signal of each neutron detector, signal selection means sequentially selects and digitally converts each output of these first filter circuits, and the signal selection means a transmission means for serially transmitting a digital signal from the means; and a high-speed regenerating means for regenerating the digital signal transmitted by the transmission means into each output signal of each neutron detector at a speed equal to or higher than the speed selected by the signal selection means. A reactor neutron flux monitoring device that attempts to achieve the above object by comprising a signal reproducing means and an average value calculation means for filtering the digital signal transmitted by the transmission means and calculating the average value of the reactor output, etc. be.

(Function) By providing such a means, the output signals of each neutron detector are filtered by the first filter circuit, and sequentially selected and converted into digital data by the signal selection means. This digital signal is serially transmitted by the transmission means, and the transmitted digital signal is regenerated into each output signal of each neutron detector by the high-speed signal regeneration means at a speed equal to or higher than the selection speed of the signal selection means. , and the simultaneously transmitted digital signals are filtered by the average value calculating means to calculate the average value of the reactor output, etc.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a reactor neutron flux monitoring device. Each of the neutron detectors 1-1 to 1-n is arranged in the reactor core, and each of these neutron detectors 1-1 to 1-n receives a signal via a first filter circuit etc.-1 to 5-n. Selection means 6
It is connected to the.

Here, to explain the configuration of each of the first filter circuits 5-1 to 5-n, these first filter circuits 5-1 to 5-n have the same configuration, and as shown in FIG. 1-
A current limiting circuit 7 is provided that protects the subsequent stage circuit when an abnormally excessive signal flows from 1 to 1-n, and this current limiting circuit 7 includes an analog filter circuit 8 that removes noise components. An analog amplifier 9 and a voltage isolator 10 are connected in series. In addition, the current limiting circuit 7 includes each neutron detector 1-1 to
A power supply device 11 is connected to supply power to 1-n. Note that the voltage isolating device 10 prevents power from the power supply device 11 from being supplied to the signal selection means 6 side.

The signal selection means 6 includes each first filter circuit 51 to 5-n.
It has a function of sequentially selecting and digitally converting each output of The configuration is such that an A/D converter 13 is connected to the output terminal.

An optical transmission means 14 is connected to this A/D converter 13. This optical transmission means 14 serially transmits the digital signal from the A/D converter 13, and its configuration is such that an electric signal is provided on the detector side and converts the digital signal from the A/D converter 13 into an optical signal. - Connecting the optical converter 15, the optical-to-electrical converter 16 provided in the central control room and converting the optical signal into a digital signal, and the electric-to-optical converter 15 and the optical-to-electrical converter 16. It consists of an optical fiber 17.

The central control room is equipped with high-speed signal reproducing means 18 and average value calculating means 19. The high-speed signal reproducing means 18 reproduces the digital signal transmitted by the optical transmission means 14 into each output signal of each of the neutron detectors 1-1 to 1-n at a speed equal to or higher than the speed selected by the signal selection means 6. It has the function of decoding the digital signal from the optical-to-electrical converter 16 at a high conversion speed, for example, at a speed higher than the selection speed at the analog multiplexer 12, and decoding it to each neutron detector 1.
-1 to 1-n is provided, and D/A converters 21-1 to 21-n are connected to each output terminal of this decoder 20, and these D/A
An arithmetic monitoring device 22 is connected to the converters 21-1 to 21-n.

However, for example, the D/A output of the D/A converter 21-1 reproduces the output signal of the neutron detector 1-1, and the D/A output of the D/A converter 21-2 reproduces the output signal of the neutron detector 1-2. This results in the reproduction of the output signal. The arithmetic and monitoring device 22 has a function of receiving each output signal from each of the D/A converters 21-1 to 21-n and monitoring the neutron flux within the reactor core.

On the other hand, the average value calculation means 19 has a function of filtering the digital signal from the optical-electrical converter 16 to calculate the average value of the reactor output, etc., and calculates the average value of the reactor output, etc. A second filter circuit 23 that filters each digital signal from -1 to 1-n, and an arithmetic monitoring device 24 that receives the filter output of this second filter circuit 23 and calculates the average value of the reactor output, etc. It is configured.

Next, the operation of the apparatus configured as described above will be explained.

Each of the neutron detectors 1-1 to 1-n detects neutrons in the reactor core and outputs a signal corresponding to the amount of neutrons. The output signals of these neutron detectors 1-1 to 1-n are noise-removed by respective first filter circuits 5-1 to 5-n, and only effective signal components are amplified by an analog amplifier 9, and then sent to an analog multiplexer 12. sent to. This analog multiplexer 12 includes each first filter circuit 5.
-1 to 5-n each neutron detector 1-1 to 1-
Sequentially select n output signals, e.g. neutron detector 1-1~
Select in the order of 1-n. Each selected signal is A/D
digitized by a converter 13 to an electro-optical converter 1
Sent to 5.

This electro-optical converter 15 converts the sequentially sent digital signals into optical signals and sends them to the optical fiber 17. In this case, the optical signals are optical transmission data D1 of the neutron detector 1-1, optical transmission data D2 of the neutron detector 1-2, and so on, as shown in FIG. ..., and these optical transmission data D1
D2... is each neutron detector 1-1.1-2. ...
, 1-n numbers N, , N2 . . . and corresponding respective neutron detectors 1-1° 1-2. ..., 1-0 output data S
It is formed from +S2... The optical signal is then transmitted through the optical fiber 17 to the central control room side.
The light is received by an electrical converter 16 and converted into an electrical digital signal.

This digital signal is sent to one decoder and the second filter circuit 23 simultaneously. Among these, the decoder 19 selects the detector numbers N and N2 recorded in the digital signal at a speed faster than the selection speed of the analog multiplexer 12.
... is decoded and each neutron detector 1 is decoded as shown in Figure 4.
-1.1-2゜...1-n different digital data D
, , D2... As a result, for example, data D
1 is sent to the D/A converter 21-1, and data D2 is sent to the D/A converter 21-1.
The signals are sent to the A converter 21-2, converted into analog signals, and sent to the arithmetic monitoring device 22. In this way, the arithmetic and monitoring device 22 receives each output signal from each D/A converter 21-1 to 21-n and monitors the neutron flux within the reactor core.

On the other hand, at the same time, the second filter circuit 23 filters each digital signal and sends it to the arithmetic monitoring device 24.
The average value of the reactor output is calculated based on the output of the filter.

In this way, in the above embodiment, each neutron detector 1
-1 to 1-n output signals are filtered and sequentially selected by the signal selection means 6 and converted into digital signals, and the digital signals are converted into optical signals and serially transmitted.
This transmitted optical signal is regenerated into each output signal of each neutron detector 1-1 to 1-n by the high-speed signal reproducing means 18 at a speed higher than the selection speed of the signal selection means 6, and at the same time, the transmitted optical signal is Since the signal is filtered by the average value calculating means 19 to calculate the average value of the reactor output, etc., it is possible to improve noise resistance and reduce the number of cables. Furthermore, each output signal of each of the neutron detectors 1-1 to 1-n can be reproduced with high precision and at high speed, improving responsiveness, and at the same time, the ψ ion flux in the reactor core can be monitored. In this case, the specific number of second filter circuits 23 can be changed to any value, and various signal changes can be obtained by changing the sampling period. Therefore, malfunctions of the nuclear reactor during operation can be detected at an early stage from the results of these monitoring.

Note that the present invention is not limited to the above-mentioned embodiment, and may be modified without departing from the spirit thereof. For example, A
/D converter 13 connects each first filter circuit 5-1, 5-2.
... 5-n and the analog multiplexer 12; in this case, the analog multiplexer 12
It is possible to eliminate switching noise caused by

[Effects of the Invention] As detailed above, the present invention has excellent noise resistance, reduces the number of cables, and has high responsiveness that reproduces the output signal of the neutral T@ output with high accuracy. It is possible to provide a nuclear reactor neutron flux monitoring device that can simultaneously measure average chemotaxis.

[Brief explanation of drawings]

1 to 4 are diagrams for explaining one embodiment of a nuclear reactor neutron flux monitoring device according to the present invention, in which FIG. 1 is a configuration diagram and FIG. 2 is a concrete diagram of the first filter circuit. A configuration diagram,
FIG. 3 is a schematic diagram of a transmitted optical signal, FIG. 4 is a schematic diagram for explaining the operation of the signal reproducing means, and FIG. 5 is a configuration diagram of a conventional device. 1-1 to 1-n...neutron detector, 5-1 to 5-n.
...first filter circuit, 6...signal selection means, 12.
...Analog multiplexer, 13...A/D converter, 14...Transmission means, 15...Electro-optical converter, 1
6... Optical-electrical converter, 17... Optical fiber, 18
. . . high-speed signal reproducing means, 19 . . . average value calculation means,
20-...Decoder, 21-1 to 21-nD/
A converter, 22... Arithmetic monitoring device, 23... Second filter circuit, 24... Arithmetic monitoring device.

Claims (1)

[Claims] In a reactor neutron flux monitoring device that receives each output signal from a plurality of neutron detectors arranged in a reactor core and monitors the reactor output during power operation, the output signal of each of the neutron detectors is Filter each first
A filter circuit, a signal selection means for sequentially selecting and digitally converting each output of the first filter circuit, a transmission means for serially transmitting the digital signal from the signal selection means, and a digital signal transmitted by the transmission means. high-speed signal regeneration means for regenerating each output signal of each of the neutron detectors at a speed equal to or higher than the selection speed of the signal selection means; 1. A nuclear reactor neutron flux monitoring device, comprising: average value calculation means for calculating an average value of reactor output, etc.