JPH0933686A - Control rod position instrumentation device and system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent simultaneous malfunctioning state of functions due to circuit failure from occurring in a control rod position instrumentation device having functions of control-rod position-detection and relative position deviation monitoring. SOLUTION: A control-rod position instrumentation device 26 has an S/D conversion part 27 to convert a control-rod position signal output from an in-core control-rod position detector (synchronized oscillator) 25 to a digital signal, a control-rod position transmission controller 29 to transmit the digitized control-rod position signal to an external controller, and a relative position deviation monitoring device 30 to monitor the relative position deviation of the self control rod from other control-rod by inputting the control-rod position signal output from the S/D conversion part 27 and the control-rod position signal output from the S/D conversion circuit of the control-rod position instrumentation device. The relative position deviation monitoring device 30 and the control-rod position transmission controller 29 are provided independently with the separated power sources and hardware.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a control rod position instrumentation device and a control rod position instrumentation system applied to a nuclear power plant.

[0002]

2. Description of the Related Art Nuclear energy utilization technology has been developed as one of the pillars of energy saving and clean energy to cope with the increasing energy demand in Japan. It is expected that hydrogen energy will be used in the future, and as a process to mass-produce hydrogen inexpensively in large quantities, the development of a high-temperature gas reactor that can generate high-temperature steam by high-temperature gas at 700 to 950 ° C is under consideration. Has been done.

Although the BWR type reactor and the high temperature gas reactor are different from each other in the structure of the reactor, the control rod driving method and the position detecting method are the same. The case where a nuclear reactor is used will be described.

FIG. 7 is a diagram showing the structure of a conventional control rod position detection / drive system. The motor speed command a issued by the control rod operation controller 1 is sent to the motor drive unit 2, and the motor drive command b issued by the motor drive unit 2 is sent to the control rod drive motor 3 installed under the reactor 4. . As a result, the position of the control rod 5 is changed. The position of the control rod 5 is detected by a control rod position detector 6 (hereinafter referred to as a synchro oscillator 6) installed in the lower portion of the nuclear reactor 4, and is detected as a voltage signal C1 in the control rod position instrumentation device 10. S / D
It is sent to the conversion unit 7. The synchro oscillator 6 and the control rod position instrumentation device 10 are provided for each individual control rod.

The S / D conversion unit 7 converts the voltage signal C1 sent from the synchro oscillator 6 into a digital signal, and outputs the S / D signal.
The data D1 (D1 = {d1, d2, ... dn}) is sent to the interface unit 8. Note that d1, d2, ..., Dn indicate that the S / D data D1 has an n-bit configuration. Interface section 8
Sends a PI / O bus output E (E = {e1, e2, ..., En}) to the controller 9 in response to a read request from the control rod position transmission controller 9. Control rod position transmission controller 9
The control rod position signal f1 processed therein is sent to the control rod operation controller 1. Note that e1, e2, ..., en are the above d1, d2,
.., dn indicates that the PI / O bus output E has an n-bit configuration. The control rod operation controller 1 to which the control rod position signal f1 is input outputs the deviation calculation processing result between the target control rod position and the control rod position signal f1 to the motor drive unit 2 as the motor speed command a.

FIG. 8 shows an S / D in the control rod position instrumentation device 10.
It is a figure which shows the structure of the conversion part 7. The voltage signal C1 sent from the synchro oscillator 6 is input to the S / D converter 7a in the S / D converter 7. The S / D converter 7a converts the voltage signal C1 into a digital signal at a constant cycle in accordance with the first clock signal in the S / D converter 7, and outputs the S / D data D1.
(D1 = {d1, d2, ... dn}) is sent to the interface unit 8.

FIG. 9 is a diagram showing the structure of the interface unit 8. S / D data D1 sent from the S / D converter 7
Is input to the buffer 11. At that time, the S / D converter 7
Is generating a signal BSY indicating that the S / D conversion is being performed, the buffer 11 is in a hold state in which data writing is prohibited. As a result, writing of unstable control rod position data into the buffer 11 during S / D conversion is prohibited. Further, in order to stabilize the data output to the control rod position transmission controller 9, the buffer 11 is in the hold state while the control rod position transmission controller 9 is generating the signal RD indicating that the controller is being read. The controller reading signal RD is
It is generated at a constant cycle according to the second clock in the controller 9 when a read request is made. The above-mentioned S / D converting signal BS
Y and the controller reading signal RD are OR
Data latch command h is sent to the buffer 11 via the gate 12.
Supplied as. The buffer 11 responds at the rising edge of the input of the data latch command h, and holds the data while the data latch command h is at the H level.

FIG. 10 shows the operation timing of each circuit shown in FIG. In the figure, HD indicates a period during which the buffer 11 is holding data, and ST indicates a state during S / D conversion, that is, during conversion of the control rod position into a digital signal. The S / D converting signal BSY is at H level during S / D conversion, and the controller reading signal RD is also at H level during controller reading. Data is held in the buffer 11 while either the S / D converting signal BSY or the controller reading signal RD is at the H level. Then, the S held in the buffer 11
The / D data D1 is ANDed with the controller reading signal RD by the AND gate 13, and the result is PI / O.
It is output to the control rod position transmission controller 9 as a bus output E.

[0009]

By the way, the high temperature gas furnace has a monitoring function of monitoring the relative position deviation of each control rod and scramming the furnace as the worst case when the relative position deviation becomes large. . When this monitoring function is also provided in the control rod position instrumentation device of the BWR type reactor, the control rod position data obtained by the control rod position instrumentation device of another control rod is taken into the control rod position transmission controller 9. A possible method is to obtain the relative position deviation from the control rod position obtained by the self control rod position instrumentation device. However, in this case, not only the control rod position detection function but also the relative position deviation monitoring function of each control rod is disabled due to a failure of the control rod position transmission controller 9.

In the conventional control rod position instrumentation device, the following points are also a concern. The S / D conversion unit 7 and the control rod position transmission controller 9 operate using different clocks. Therefore, as shown in part A of FIG.
If the controller read RD rises immediately after the conversion-in-progress signal BSY falls, the width from the falling edge to the rising edge of the data latch command h becomes smaller than the pulse width of the latch response of the buffer 11, and as a result, as shown in FIG. As shown in part B of the above, the buffer 11 is not brought into the hold state at the timing when the data latch command h rises next time, and the control rod position transmission controller 9 cannot read the control rod position data correctly.

The present invention has been made to solve the above-mentioned problems. Even if the control rod position transmission circuit fails, the control rod position deviation monitoring circuit can continue to monitor the relative position deviation of each control rod. The purpose is to provide an instrumentation device.

Further, according to the present invention, even if the S / D conversion circuit and the control rod position transmission circuit are configured to operate according to different clocks, the buffer circuit can be put in the hold state at the correct timing, and the control can be performed. It is possible to prevent defective reading of data from the buffer circuit by the rod position transmission circuit.

Further, according to the present invention, the control rod position instrumentation device is multiply provided for each control rod, so that the position of the control rod position can be continuously detected even when some of the control rod position instrumentation devices are out of order. It is also an object of the present invention to provide a control rod position instrumentation system capable of monitoring relative position deviation.

[0014]

In order to achieve the above-mentioned object, the control rod position instrumentation device of the present invention converts a control rod position signal output from a control rod position detector in a furnace into a digital signal. Provided as an S / D conversion circuit, a control rod position transmission circuit that transmits a control rod position signal digitized by the S / D conversion circuit to an external controller, and a circuit that operates independently of the control rod position transmission circuit. , The control rod position signal output from the S / D conversion circuit and the control rod position signal output from the S / D conversion circuit of another control rod position instrumentation device And a relative position deviation monitoring circuit for obtaining a relative position deviation.

In the present invention, since the relative position deviation monitoring circuit is provided as a circuit that operates independently of the control rod position transmission circuit, even if the control rod position transmission circuit fails, the control rod position deviation monitoring circuit will not operate. The relative position deviation of each control rod can be continuously monitored. Further, the present invention is configured by providing optical transmission means for optically transmitting the control rod position signal output from the S / D conversion circuit to the relative position deviation monitoring circuit. In this way, the control rod position signal output from the S / D conversion circuit is optically transmitted to the relative position deviation monitoring circuit, so that the relative position deviation monitoring circuit can prevent the influence of the failure of the control rod position transmission circuit. You no longer have to worry.

Further, the present invention further comprises an S / D conversion circuit for converting the control rod position signal output from the control rod position detector in the furnace into a digital signal according to the first clock, and an S / D conversion circuit.
A buffer circuit that holds the control rod position data output from the conversion circuit, a control rod position transmission circuit that reads the control rod position data from the buffer circuit according to a second clock and transmits it to an external controller, and a third clock are generated. A clock generator for controlling and a first signal output from the S / D conversion circuit indicating that conversion is currently being performed and the control rod position data output from the control rod position transmission circuit are currently being read. The timing of each signal is input using the third clock so that the minimum value of the period in which the second signal is input and these signals are both invalid is approximately ½ of the cycle of the third clock. A signal processing means for shifting and a means for holding the buffer circuit in a hold state during a period in which at least one of the first signal and the second signal is effective are configured.

As described above, in the present invention, the signal processing means outputs the first signal output from the S / D conversion circuit and indicating that the conversion is currently being performed, and the current control rod output from the control rod position transmission circuit. By inputting the second signal indicating that the position data is being read, the minimum value of the period in which these signals are both invalid is approximately 1/2 of the third clock cycle.
Since the timing of each signal is shifted using the third clock so that
Suppose that 2 is the width that allows the buffer circuit to respond to latching
Even if the D conversion circuit and the control rod position transmission circuit are configured to operate using different clocks, the buffer circuit can be set to the hold state at an appropriate timing, and the data from the buffer circuit by the control rod position transmission circuit can be set. Read failure can be prevented.

The control rod position instrumentation system of the present invention further includes an S / D conversion circuit for converting a control rod position signal output from a control rod position detector in the furnace into a digital signal, and an S / D conversion circuit.
It is provided as a control rod position transmission circuit that transmits the control rod position signal digitized by the / D conversion circuit to an external controller and a circuit that operates independently of the control rod position transmission circuit, and is output from the S / D conversion circuit. Relative position deviation that determines the relative position deviation between the own control rod and another control rod by inputting the generated control rod position signal and the control rod position signal output from the S / D conversion circuit of another control rod position instrumentation device. It is characterized in that a control rod position instrumentation device having a monitoring circuit is multiply provided for each control rod together with a control rod position detector in the furnace.

By providing multiple control rod position instrumentation devices for each control rod in this way, even if some of the control rod position instrumentation devices are out of order, control rod position detection and relative control can be continued. Position deviation monitoring can be performed.

[0020]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a diagram showing a configuration of a control rod position detection / drive system in a nuclear reactor which is a first embodiment, and FIG. 2 is a diagram showing a configuration of a control rod position instrumentation device therein.

As shown in FIG. 1, the reactor 20 includes a motor drive unit 22 and a motor 2 corresponding to each control rod 21.
3, a clutch 24, a control rod position detector 25 (hereinafter referred to as a synchro oscillator 25), and a control rod position instrumentation device 26 are provided.

As shown in FIG. 2, the control rod position instrumentation device 26 comprises an S / D conversion unit 27, an interface unit 28, a control rod position transmission controller 29, and a control rod position deviation monitoring device 30. . Here, the control rod position deviation monitoring device 30 and the control rod position transmission controller 29 are independently provided by separate power sources and separate hardware.

The operation of the control rod position detection / drive system corresponding to one control rod will be described below. The motor speed command a issued by the control rod operation controller 31 is the motor drive unit 22.
Drive command b sent to the motor drive unit 22 by the motor drive unit 22
Is sent to a motor 23 for driving the control rod. The power of the motor 23 causes the wire 32 and the pulley 3 to pass through the clutch 24.
The position of the control rod 21 suspended by 3 is changed. The clutch 24 is disengaged in response to the scrum request signal, and the control rod 21 is dropped. The position of the control rod 21 is detected by the synchro oscillator 25, and the voltage signal C1 is sent to the control rod position instrumentation device 26.

The S / D conversion unit 27 in the control rod position instrumentation device 26 uses a voltage signal C1 sent from the synchro oscillator 25.
Is received and converted into a digital signal. The output is S /
D data D1 (D1 = {d1, d2, ..., D13}) is sent to the interface unit 28 and the control rod position deviation monitoring device 30. The interface unit 28 responds to the reading request from the control rod position transmission controller 29,
To PI / O bus output E (E = {e1, e2, ..., E13}). The control rod position signal f1 processed by the control rod position transmission controller 29 is sent to the control rod operation controller 31. The control rod operation controller 31 obtains the deviation between the target control rod position and the control rod position signal f1 and outputs the calculation result to the motor drive unit 22 as a motor speed command a.

Further, the control rod position deviation monitoring device 30 includes the S / D data D2 from the S / D converter 27 in its own control rod position instrumentation device 26 and all other control rod position instrumentation devices 26.
The S / D data D2 is received and the relative position deviation of each control rod is calculated. When the calculated relative position deviation exceeds the set value, the control rod position deviation large signal g1 is output as a scrum request signal.

The feature of the control rod position instrumentation device 26 of this embodiment is that the control rod position deviation monitoring device 30 and the control rod position transmission controller 29 therein are provided independently of the power source and the hardware. There is a point. This allows
It is possible to prevent the functions of both circuits from being disabled at the same time due to the failure of one circuit, and it is possible to reduce the probability that these functions will be disabled for each individual function.

FIG. 3 is a diagram showing the internal structure of the S / D converter 27. As shown in the figure, the S / D converter 27 uses the S / D converter 27a for converting the voltage signal C1 sent from the synchro oscillator 25 into a digital signal and the output of the S / D converter 27a. An insulating unit 3 that outputs certain S / D data D1 to the interface unit 10 while electrically insulating the same.
5 and the S / D data D output from the S / D converter 27a
1 is converted into an optical signal D2 to control rod position deviation monitoring device 30
And an optical module 36 for transmitting to the optical fiber. An optical signal D2 derived from the optical module 36 is converted into an electrical signal by an optical module 37 provided in the control rod position deviation monitoring device 30, and is input as S / D data D1.
The insulating unit 35 may be anything as long as it can transmit the output data D1 of the S / D converter 27a to the interface unit 10 while electrically insulating the data. With such a configuration, the control rod position detection system including the interface unit 28 and the control rod position transmission controller 29,
Alternatively, even if the control rod position deviation monitoring device 30 fails,
The effect will not affect the other system, and damage due to failure can be minimized.

FIG. 4 is a diagram showing the internal structure of the interface unit 28. As shown in FIG.
Reference numeral 8 denotes a clock oscillator 41, a first flip-flop circuit 42 for controlling the output of the controller reading signal RD from the control rod position transmission controller 29 based on a clock CL issued by the clock oscillator 41, and a clock oscillator. NOT gate 43 for inverting clock CL generated by 41
A second flip-flop circuit 44 for controlling the output of the S / D converting signal BSY from the S / D converter 27 based on the inverted clock which is the output of the NOT gate 43, and each flip-flop circuit 42, An OR gate 45 for taking the logical sum of the outputs of 44 and outputting it as a data latch command h;
A buffer 46 that holds the S / D data D1 output from the S / D converter 27 based on the data latch command h.
And an AND gate 47 which reads out the S / D data D1 in the buffer 46 based on the controller reading signal RD and outputs it as the PI / O bus output E to the control rod position transmission controller 29.

Next, the operation of the interface section 28 will be described with reference to the timing chart of FIG. Here, the pulse width of the clock CL generated by the clock oscillator 41 is set to a width in which the buffer 46 can make a latch response.

The first flip-flop circuit 42 inputs the controller reading signal RD from the D terminal and outputs it from the Q terminal at the rising edge of the clock CL. RD1 is an output signal of the first flip-flop circuit 42.
For example, the rising position 51 of the controller reading signal RD is shifted to the rising position of 52 of the clock CL. On the other hand, the second flip-flop circuit 44
Input D / D converting signal BSY from Q terminal
Output from the D terminal at the falling edge of L. B
SY1 is an output signal of the second flip-flop circuit 44. For example, the falling position 53 of the S / D converting signal BSY is shifted to the rising position of the clock CL 54. The outputs RD1 and BSY1 of the flip-flop circuits 42 and 44 are supplied to the buffer 46 as the data latch command h through the OR gate 45, and the buffer 46 outputs the output of the S / D converter 27 according to the data latch command h. The S / D data D1 is held.

In this interface section 28, at least the clock CL is set during the L level period of the data latch command h.
Of the pulse width, and the buffer 46 does not become smaller than the latch response width. Therefore, due to the S / D converter 27 and the control rod position transmission controller 29 operating using different clocks, the S / D
Even if the controller reading signal RD rises immediately after the conversion signal BSY falls, the buffer 46
Responds to the latch normally and can hold the S / D data D1.

By the way, each flip-flop circuit 42,
Although 44 operates with a common clock CL, there is a slight time difference in clock reception between the flip-flop circuits. Therefore, if the flip-flop circuits 42 and 44 are both set / reset at the rising (or falling) timing of the clock CL, the flip-flop circuits 42 and 44 are placed between the controller reading signal RD1 and the S / D converting signal BSY1. A slight time difference occurs, and the L level width of the data latch command h becomes smaller than the latch response width of the buffer 46.

On the other hand, in this embodiment, the controller reading signal RD is controlled at the rising edge of the clock CL, and the S / D conversion signal BSY is controlled at the falling edge of the clock CL. The above-mentioned adverse effect due to the subtle time difference of clock reception between the clock circuits is eliminated, and the L level period of the data latch command h can be secured at least approximately 1/2 of the cycle of the clock CL (approximately the pulse width).

The AND gate 47 may be configured to receive the controller read signal RD1 which is the output of the first flip-flop circuit 42 instead of the controller read signal RD. It is also possible to adopt a configuration without the AND gate 47.

Next, a control rod position instrumentation device according to a second embodiment of the present invention will be described with reference to FIG.

As shown in the same figure, this control rod position instrumentation system has 6 control rods for one control rod 61 in the reactor 60.
The control rod position instrumentation device of 2, 63, 64 is provided in triplicate. Similarly, three synchro oscillators 65, 66, 67 are provided in the reactor 60, and the control rod position data C1, C2, C3 which are the outputs of the individual synchro oscillators respectively correspond to the respective control rod position instrumentation devices. It is configured to output to 62, 63 and 64. Each control rod position instrumentation device 62, 6
The control rod position signals f1, f2, f3, which are the outputs of the control rod position transmission controllers in 3, 64, are input to the control rod operation controller 68, and the control rod operation controller 68 targets these control rod position signals. The deviation from the position is obtained, and the calculation result is output to the motor drive unit 69 as the motor speed command a.

When a failure occurs in the synchro oscillator or the control rod position instrumentation device of any system, the control rod operation controller 68 invalidates the input from the failed control rod position instrumentation device, and the remaining two systems. The control rod operation is executed for the input from. In this embodiment, since the control rod position instrumentation devices are provided in triple layers, even if two systems fail, control rod operation can be continued with the remaining one system, and control rod position deviation monitoring of the remaining systems is possible. The control rod position deviation large signals g1 to g3 output from the apparatus can cause the reactor to scram. It is needless to say that the control rod position instrumentation device corresponding to each control rod may be provided in double or quadruple or more.

[0039]

As described above, according to the present invention, the relative position deviation monitoring circuit is provided as an independent hardware by separating the control rod position transmission circuit and the power source, so that the control rod position transmission circuit fails. Even so, the control rod position deviation monitoring circuit can continue to monitor the relative position deviation of each control rod.

Further, according to the present invention, the control rod position signal output from the S / D conversion circuit is optically transmitted to the relative position deviation monitoring circuit, so that the influence of the failure of the control rod position transmission circuit can be prevented. There is no need to worry about the relative position deviation monitoring circuit.

Further, according to the present invention, the first signal output from the S / D conversion circuit indicating that the conversion is currently being performed and the current control rod position data output from the control rod position transmission circuit are being read. The minimum value of the period in which the second signal indicating that there is both is invalid is approximately 1 of the period of the third clock.
Even if the S / D conversion circuit and the control rod position transmission circuit are configured to operate using different clocks by shifting the timing of each signal using the third clock so that it becomes / 2, The buffer circuit can be set to the hold state at an appropriate timing, and the data reading failure from the buffer circuit by the control rod position transmission circuit can be prevented.

Further, according to the control rod position instrumentation system of the present invention, the control rod position instrumentation device is multiply provided for each control rod, so that when some control rod position instrumentation device fails. Also in the above, the control rod position detection and relative position deviation monitoring can be continuously performed.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a control rod position detection / drive system in a nuclear reactor including a control rod position instrumentation device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a control rod position instrumentation device in FIG.

FIG. 3 is a diagram showing a configuration of an S / D conversion unit in the control rod position instrumentation device of FIG.

4 is a diagram showing a configuration of an interface unit in the control rod position instrumentation device of FIG.

5 is a timing chart for explaining the operation of the interface unit of FIG.

FIG. 6 is a diagram showing a configuration of a control rod position instrumentation device which is a second embodiment of the present invention.

FIG. 7 is a diagram showing a configuration of a conventional control rod position detection / drive system.

8 is a diagram showing a configuration of an S / D conversion unit in the control rod position instrumentation device of FIG.

9 is a diagram showing the configuration of an interface unit in the control rod position instrumentation device of FIG.

FIG. 10 is a timing chart for explaining the operation of the interface unit of FIG.

[Explanation of symbols]

 21 ... Control rod 25 ... Control rod position detector (synchro transmitter) 26 ... Control rod position instrumentation device 27 ... S / D conversion unit 28 ... Interface unit 29 ... Control rod position transmission controller 30 ... Control rod position deviation monitoring device 35 Insulators 36, 37 Optical module 41 Clock generator 42 First flip-flop circuit 43 NOT gate 44 Second flip-flop circuit 45 … OR gate 46 …… Buffer 47 …… AND gate

Claims (4)

[Claims] 1. A control rod position instrumentation device provided for each individual control rod, wherein a control rod position signal output from a control rod position detector in a furnace for detecting the position of the control rod is converted into a digital signal. S / D conversion circuit for conversion, control rod position transmission circuit for transmitting control rod position signal digitized by this S / D conversion circuit to an external controller, and independent operation for this control rod position transmission circuit The control rod position signal output from the S / D conversion circuit and the control rod position signal output from the S / D conversion circuit of another control rod position instrumentation device are input as a control rod provided as a circuit. A control rod position instrumentation device, comprising: a relative position deviation monitoring circuit for obtaining a relative position deviation from another control rod. 2. The control rod position instrumentation device according to claim 1, further comprising optical transmission means for optically transmitting a control rod position signal output from the S / D conversion circuit to the relative position deviation monitoring circuit. A characteristic control rod position instrumentation device. 3. A control rod position instrumentation device provided for each individual control rod, wherein a control rod position signal output from a control rod position detector in the furnace for detecting the position of the control rod is used as a first control rod position signal. An S / D conversion circuit for converting into a digital signal according to the clock, a buffer circuit for holding the control rod position data output from this S / D conversion circuit, and reading of the control rod position data from this buffer circuit according to the second clock. A control rod position transmission circuit for transmitting to an external controller, a clock generator for generating a third clock, a first signal output from the S / D conversion circuit indicating that conversion is currently being performed, and the control Input the second signal output from the rod position transmission circuit, which indicates that the control rod position data is currently being read, and set the minimum value of the period during which both of these signals are invalid. A signal processing unit that shifts each timing of the first signal and the second signal using the third clock so that the timing of the third clock is approximately ½ of the cycle of the third clock. Means for putting the buffer circuit in a hold state during a period in which at least one of the signal of 1) or the second signal is valid. 4. An S / D conversion circuit for converting a control rod position signal output from a control rod position detector in a furnace for detecting the position of the control rod into a digital signal, and digitized by this S / D conversion circuit. It is provided as a control rod position transmission circuit that transmits the control rod position signal to an external controller, and a circuit that operates independently with respect to this control rod position transmission circuit,
The control rod position signal output from the S / D conversion circuit and the control rod position signal output from the S / D conversion circuit of another control rod position instrumentation device are input to connect the self control rod and the other control rod. A control rod position instrumentation device having a relative position deviation monitoring circuit for obtaining a relative position deviation, and the control rod position detector in the furnace are multiply provided for each control rod. Position instrumentation system.