JPS63175799A - Nuclear-reactor pressure relief safety valve blow-off operating device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Objective of the invention] (Industrial application field) The present invention provides a reactor pressure relief safety valve (
Hereinafter, it will be referred to as the S/R valve. ) Regarding the reactor pressure relief safety valve blowout operation IA which controls the operation of the nuclear reactor pressure relief safety valve.

(Prior art) Generally, in a nuclear power plant, when the reactor pressure rises transiently, the pressure rise inside the reactor is suppressed by releasing the steam inside the reactor from the main steam pipe into the suppression pool water. Multiple S/R valves are installed.

A conventional S/R valve blow-off actuating device will be described below with reference to the drawings.

As shown in FIG. 8, the nuclear reactor 1 is housed in a reactor containment vessel 2, and a plurality of main steam pipes 3A to 3A extend from the reactor 1.
S/R valves 4A to 4D#I are respectively placed on 3D. Here, for convenience of explanation, four S/R valves 4A to 4D are shown. Pipes 5A to 5D extend from these S/R valves 4A to 4D and reach the suppression pool 6 below the reactor containment vessel 2, and the steam release lower A into the suppression pool water 6a.
~7D is provided.

In addition, pressure detectors 8A to 8 that detect the pressure inside the reactor 1
The number of valves D corresponds to the number of S/R valves 4A to 4D. The detected values of these pressure detectors 8A to 8D1 are set in several stages, and the reactor pressure signals 9△ to 9D from these pressure detectors 8A to 8D are input to control the predetermined S/R valve. A reactor pressure logic circuit 10 is provided which operates 4A-4D. Here, it is assumed that the detected value of the pressure detector 38A is set to be the lowest, and then the detected value of the pressure detector 8B, the pressure detector 8C1, and the pressure detector 8D are set to be higher stepwise in this order.

In the event that the pressure inside the reactor 1 rises, the pressure detector 8A, which is set to the lowest value, detects this and outputs a reactor pressure signal 9A to the reactor pressure logic circuit 10. The reactor pressure logic circuit 10 to which this reactor pressure signal 9A is inputted has a predetermined S value based on the pressure logic circuit signal 11A.
Activate /R valve 4A. When this S/R valve 4A operates, steam in the reactor 1 is guided to the suppression pool 6 through the pipe 5'A, and the suppression pool water 6a
released into the body. The steam released into the suppression pool water 6a is condensed due to the cooling effect of the water, and is
The rise in pressure within is suppressed t11.

If the pressure inside the reactor 1 rises further, the pressure detector 8B, which is set to the next lowest value, detects this and outputs a reactor pressure signal 9B, which similarly increases the S/R valve 4B. Activate the 2g S/R valve 4A.

Blow out steam from 4B. Even when the pressure further increases, the S/R valves 4G and 40 are sequentially operated in the same manner.

(Problem to be Solved by the Invention) In the S/R valve blow-off actuating device described above, when a transient increase in reactor pressure continues for a long time, the pressure detector 8A set to the lowest pressure always Outputs a furnace pressure signal of 9A,
The corresponding S/R valve 4A will always operate.

Therefore, the steam released from this S/R valve 4A is always released from the same steam release lower A.

Therefore, it is conceivable that the suppression pool water 6a is exposed to a local temperature increase, and the blown-out steam is not sufficiently condensed due to a reduction in the cooling effect accompanying the increase in water temperature.

The present invention was made in consideration of the above circumstances, and it measures the temperature of the suppression pool water and sequentially blows out steam from the S/R valve with steam release [] to the area where the water temperature is lowest and the cooling effect is highest. The purpose of the present invention is to provide a reactor pressure relief safety valve blow-off actuating device that can perform the following functions.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides a solution to the problem by blowing out the steam inside the reactor into the suppression pool water through the reactor pressure relief safety valve when the reactor pressure rises transiently. In the reactor pressure relief safety valve blowout operating device that suppresses the pressure rise of the It comprises a selection circuit to be activated.

(Function) When the pressure of the reactor rises transiently, the selection circuit of the present invention selects one of the S/R valves that has a steam release port in a location where the water temperature of the suppression pool is low. Operates sequentially. Steam is blown out from the steam opening,
When the water temperature in that area rises, S/R valves with steam release ports located in other locations with lower water temperatures operate preferentially. In this way, since the S/R valves that have steam release ports are always operated in sequence where the water temperature of the suppression pool is low, local increases in the water temperature of the suppression pool are prevented.
The steam condensation effect is improved.

(Example) A practical example of the reactor pressure relief safety valve blow-off operating device according to the present invention will be described with reference to the drawings.

As shown in FIG. 1, S/R valves 4A to 4D are provided on a plurality of main steam pipes 3A to 3D extending from the nuclear reactor 1. Here, four S/R valves 4A to 4D are shown for convenience of explanation. Pipes 5A to 5 extending from these S/R valves 4A to 4D
D reaches the suppression pool 6 as in the conventional case, and has steam opening lowers A to 7D in the suppression pool water 6a.

On the other hand, the reactor 1 includes pressure detectors 8A to 8D that detect the pressure inside the reactor 1 and output reactor pressure signals 9A to 9D.
is provided. This reactor pressure signal 9A is outside the reactor.
A reactor pressure logic circuit 10 is provided which inputs .about.9D.

This reactor pressure logic circuit 1o is a pressure logic circuit signal 11A.
~11D is output to the S/R valve blowout selection circuit 15. Furthermore, this S/R valve blowout selection circuit 15 inputs temperature signals 17A to 17D from temperature detectors 16A to 16D provided near each of the steam release lowers A to 7D in the suppression pool 6, respectively. These temperature detectors 16A
~16D are each steam release lower A~7D and each S/R valve 4
One-to-one correspondence with A to 4D.

These temperature signals 17A to 170 and the pressure logic circuit signal 1
The S/R valve blowout selection circuit 15 to which S/R valves 1A to 11D are input operates sequentially from S/R valves 4A to 4D having steam release ports '7A to 7D in locations where the water temperature of the suppression pool 6 is low. Outputs R valve actuation signals 18A to 18D.

The S/R valve blowout selection circuit 15 receives temperature signals 17A-1 from temperature detectors 16A-16D, as shown in FIG.
7D and pressure logic circuit signals 11A to 11G from the reactor pressure logic circuit 10, temperature ranking signals 19A to 11G are input.
A temperature comparison circuit 20 that outputs 19D and the temperature signal 1
7A to 17D and the temperature ranking signals 19A to 19D from the temperature comparison circuit 20 are input to generate the identification signal 1" 21 A.
A recognition circuit 22 that outputs ~21D and this recognition circuit 22
and the pressure logic circuit signals 11A to 11D from the reactor pressure logic circuit 10 and output the S/R valve actuation signals 18A to 18D.
It consists of an R valve operation logic circuit 24.

Hereinafter, each of these circuits 20, 22, and 24 will be explained in sequence.

First, the temperature comparison circuit 20 is a circuit that determines the order of suppression pool water temperatures, and as shown in FIG. 3, it is composed of a comparison circuit 25 and timer circuits 298 to 29D. The comparison circuit 25 is a combination of a low value selection circuit 26 and a Hatake value selection circuit 27 shown in FIGS. 4 and 5.
The temperatures are ranked from the lowest to the highest, and temperature ranking signals 19A to 19D are output. At this time, the temperature ranking signal 19A having the lowest temperature is output as is, but the other temperature ranking signals 198 to 190 are reserved by providing timer circuits 29B to 29D in the middle, and the reactor pressure logic circuit 10 Pressure logic circuit signal 11 from
Output when receiving A to 11C.

Next, the recognition circuit 22 identifies the temperature around which steam release lowers A to 7D are measured by the temperature ranking signals 19A to 19D ranked by the temperature comparison circuit 20,
It converts into a contact signal (ON-OFF signal) and outputs it, and as shown in FIG.
5.

The above identification is performed by the following calculation. First, each temperature signal 17A, 17B is inputted to the adders 30A to 30D, and the bias circuit 31 applies an arbitrary bias to each of the adders 32A to 30D.
Add 2D.

For example, the amount of bias to be applied is changed, such as adding a bias called rWJ to the temperature signal 17A and adding a bias called rXJ to the temperature signal 17B.

Addition No. 1 33A to 330e, Fiiis 34A to 3 from adders 30A to 30D to which these biases are added
40 is input, and the following calculation is performed between the temperature ranking signals 19A to 19D from the temperature comparison circuit 20. for example,
In the case of the temperature ranking signal 19A having the lowest temperature, the addition signal 33A - temperature ranking signal 19A - addition signal 338
1 temperature ranking signal 19A - addition signal 33C 1 temperature ranking signal 19A - addition signal 33D 1 temperature ranking signal 19A - If the result of this calculation is addition signal 33A 1 temperature ranking signal 19A-W, then the suppression pool water has the lowest temperature. It is determined that the temperature detector 16A has detected the temperature of the temperature sensor 6a. In this way, the addition signals 33A to 330 and the temperature ranking signals 19A to
Temperature ranking signals 19A to 19D are obtained by calculation with 19D,
The correspondence with the temperature detectors 16A to 16D that measured the temperature is identified.

Further, each of the arithmetic units 34A to 34D has a gate. That is, in the arithmetic unit 34A, the result of the above-mentioned performance, the adder 3
When the bias molecule WJ added at 0A comes out, the gate is activated by the contact 36A of the contact circuit 35 as an operating condition of the S/R valve 4A having the steam release lower A near the temperature detector 16A which is the output light of the temperature signal @17A. A determination signal 37A is output to the terminal. However, when the bias molecule WJ does not appear, it is not output. This gate is the same for the other calculation units 348 to 34D, and if the calculation result of each PAti unit 348 to 34D matches the added bias, for example rXJ, the contact 3
6B, if it matches rYJ, it goes to contact 36C, and if it matches rZJ, it goes to contact 36D, and so on.

The contact circuit 35 to which each determination signal 37A to 37D is input is
Each judgment signal 37A to 370 is converted into a contact signal (ON-OFF signal) and S/R is converted into an identification signal 21A to 210.
Output to valve actuation logic circuit 24. This identification signal 21A~
At the time when 210 is output, it is already known which S/R valves 4A to 4D have steam release lowers A to 7D in the area with the lowest water temperature.

Next, the S/R valve operation logic circuit 24 controls each S/R valve 4A to
Adding the pressure condition of reactor 1 to the 4D temperature condition (which S/R valve has the steam release port in the area with the lowest water temperature),
It emits an activation signal for the S/R valves 4A to 4D.

This S/R valve operation logic circuit 24, as shown in FIG.
Input to ND circuits 40A to 40D. On the other hand, the pressure logic circuit signals 11A to 11D from the reactor pressure logic circuit 10 are input to the permission circuit 41 serving as an OR circuit, and the pressure in the reactor 1 rises transiently, causing one of the input points to rise. ON
When the state is reached, the permission signal @43 is connected to the AND circuit 40A.
Output to ~400.

Here, each AND circuit 40A to 40D will input the permission signal 43, but as explained in FIG.
Only the identification signal 21A with the lowest water temperature reaches A. Therefore, if the steam release lower A is located in the area with the lowest water temperature, and this steam release lower A corresponds to the S/R valve 4A, the pressure logic set to the lowest pressure initially When the circuit signal 11A is input, the identification signal 21A is sent to the area with the lowest water temperature in the steam release lower A.
S/R valve actuation signal 18 that actuates the S/R valve 4A with
It will be output as A.

In the above case, the pressure logic circuit signal set to the lowest pressure @
11A is also output to the timer circuit 29B of the temperature comparison circuit 20 at the same time, so at that time, the timer circuit 29B outputs the temperature ranking signal 19B having the second lowest water temperature. In other words, the pressure logic circuit signals 11A to 11D are arbitrarily fixed conditions, and the set pressures have stages, so the pressure logic circuit signal 1 is set to the lowest value.
It is output in order starting from 1A. Therefore, when the pressure logic circuit signal 11A with the lowest (pressure set) is input to the timer circuit 29B, the second lowest temperature ranking signal 19B is output, and similarly the second lowest (pressure is set) When the pressure logic circuit signal 11B is input to the timer circuit 29G, the third lowest 4th grade signal 19G is outputted.

This temperature ranking signal @19B passes through the recognition circuit 22, becomes an identification signal 21B, and reaches the AND circuit 40B. Regarding this identification signal 21B, the permission circuit 41 inputs the pressure logic circuit signal 11B set to the second lowest pressure,
When the permission signal 43 is output, the AND circuit 40B outputs the S/R valve actuation signal 18B with the steam release lower B in the area with the second lowest water temperature.

The self-holding circuit 45A inputs the S/R valve operation signal 18A, and outputs the S/R valve operation signal 18A to the S/R valve 4A, as well as to the disallowance condition output circuit 46.

This disallowing condition output circuit 46 outputs a disallowing condition signal 47 to the permitting circuit 41, and the permitting circuit 41 which has input this disallowing condition signal 47 stops outputting the permitting signal 43.

This permission circuit 41 outputs a permission signal 43 when the pressure logic circuit signal 11B is inputted again.

In this way, once the permission circuit 41 outputs the permission signal 43, it does not output the permission signal 43 until the next pressure logic circuit signal 11B is input.
When A occurs, it is held by the self-holding circuit 45A. The above description applies to other self-holding circuits 458 to 45D, A
The same applies to ND circuits 40B to 40D.

This S/R valve operation wJ logic circuit 24 is the S/R valve operation signal 1.
8A to 18D, and S/R valves 4A to 4D with steam release lowers A to 7D in the respective temperature order areas depending on the situation.
Output to. The S/R valves 4A to 4D, which receive the S/R valve actuation signals 18A to 18D, open the valves and release the steam in the reactor 1 from the steam release lowers A to 7D.

In the S/R valve blow-off actuating device configured in this way, when a transient pressure rise in the reactor occurs, this pressure rise is detected by the pressure detector 8A set to the lowest value, and the atomic A furnace pressure signal 9A is output. The reactor pressure 4f, number 9A is input to the reactor pressure logic circuit 10, and the reactor pressure logic circuit 10 outputs a pressure logic circuit signal 11A. This pressure logic circuit signal 11A is S
/R valve blowout selection circuit 15.

On the other hand, the water temperature at various locations within the suppression pool 6 is detected by each of the temperature detectors 16A to 160, and temperature signals 17A to 17D are output from each of the temperature detectors 16A to 16D to the S/R valve blowout selection circuit 15.

Here, the steam release lower A opens to the area with the lowest water temperature, followed by the steam release lower B and the steam release lower C1.
Assuming that the water temperature increases in the order of steam release lower D, the temperature signals 17A to 17D and the pressure logic circuit signal 11A are sent to the temperature comparison circuit 20 and the recognition circuit in the S/R valve blowout selection circuit 15. 22 and S/R valve actuation logic circuit 24 to output an S/R valve actuation signal @18A.

This S/R valve actuation signal 18A is a signal to actuate the S/R valve 4A, which has the steam release lower A in the area where the temperature is lowest. The S/R valve 4A receiving this S/R valve actuation signal 18A releases the steam in the reactor 1 from the steam release lower A into the suppression pool water 6a of the suppression pool 6 through the piping 5A.

When the transient pressure increase inside reactor 1 continues for a long time,
The heat of the steam released from the steam opening lower A increases the temperature of the suppression pool water 6a around the steam opening lower A. Assuming that this rise in water temperature causes the water temperature in other areas, for example, around steam open lower D, to become relatively lowest, temperature signals 17A to 17D from temperature detectors 168 to 16D
The S/R valve blowout selection circuit 15 receives the input and outputs an S/R valve operation signal 18D that operates the S/R valve 4D having the steam release lower D in the area where the water temperature is lowest.

On the other hand, the S/R valve actuation signal 18A to the S/R valve 4A having the steam release lower A in the area where the water temperature has become high is stopped.

Furthermore, when the pressure inside the reactor 1 cannot be covered by the operation of one S/R valve 7D and rises further, the pressure detector 8B set to the second lowest value detects the pressure. It is detected and a reactor pressure signal 99B is output. This reactor pressure signal 9B is input to the reactor pressure logic circuit 10, and from this reactor pressure logic circuit 10 the pressure logic circuit signal 1
1B is output.

This pressure logic circuit signal 11B and each temperature signal 17A to 17
D is input to the S/R valve blowout selection circuit 15, and the S/R valve 4C has the steam release lower C in the area with the second lowest water temperature.
An S/R valve actuation signal 18C is output to actuate the S/R valve. In this way, an actuation signal 18C is sent from the S/R valve blowout selection circuit 15 to actuate the two S/R valves 4C and 4D having steam release lowers G and 7D in the areas with the first and second lowest water temperatures.
218D is output. These two S/R valves 4C.

The operation of 4D causes the steam in the reactor 1 to be released into the suppression pool water 6a.

In addition, if the pressure increase in the reactor 1 cannot be suppressed even by the operation of the two S/R valves 4C and 4D, and by the operation of these two S/R valves 4G and 4D, the steam release lower C,
Even if the water temperature around 7D rises higher than the surroundings of other steam open lowers A and 7B, the S/
- The R valve blowout selection circuit 15 selects an appropriate S for the situation.
/R outputs valve actuation signals 18A to 18D.

In this way, according to this embodiment, the S/R has a steam release port in an area where the temperature of the suppression pool water 6a is always low.
Since the valves can be activated sequentially, the cooling effect of the suppression pool water 6a can be maximized, and the steam from inside the reactor 1 can be effectively condensed, so that the pressure rise inside the reactor 1 can be appropriately suppressed. is possible.

(Effects of the Invention) As explained above, the reactor pressure relief safety valve blow-out actuating device according to the present invention has the advantage of the reactor pressure relief safety valve blowing actuation device of the present invention, which has a steam release port located at a location where the water temperature of the suppression pool is low, among a plurality of reactor pressure relief safety valves. It has a selection circuit that operates sequentially starting with the reactor pressure relief safety valve, so when the pressure inside the reactor rises transiently, the cooling effect of the suppression pool water is maximized and the steam from inside the reactor is effectively used. This has the effect of condensing and appropriately suppressing the rise in pressure within the reactor.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing an embodiment of the reactor pressure relief safety valve blow-off operating device according to the present invention, and FIG. 2 is a block diagram showing the internal configuration of the S/R valve blow-off selection circuit provided in the above embodiment. , FIG. 3 is a block diagram showing the internal configuration of the temperature comparison circuit shown in FIG. 2, FIGS. 4 and 5 are block diagrams showing the internal configuration of the comparison circuit shown in FIG. Block diagram showing the internal configuration of the recognition circuit shown in the figure, No. 7
This figure is a block diagram showing the internal configuration of the S/R valve operating logic circuit shown in FIG. 2, and FIG. 8 is an overall configuration diagram showing a conventional S/R valve blow-off operating device. 1... Nuclear reactor, 2... Reactor containment vessel, 3A to 3D
...Main steam pipe, 4A-4D...S/R valve, 5A-5
D... Piping, 6... Suppression pool, 6a.
...Suppression pool water, 78-7D...Steam release port, 8A-8D...Pressure detector, 9A-9D...
Reactor pressure signal, 10...Reactor pressure logic circuit, II
A to 11D...pressure logic circuit signal, 15...S/R
Valve blowout selection circuit, 16A to 16D...temperature detector,
17A-17D...Temperature signal, 18A-180...
S/R valve operation signal, 19A to 19D...Temperature ranking signal, 20...Temperature comparison circuit, 21A to 21D...Identification signal, 22...Recognition circuit, 23A to 23D...S/
R valve operation signal, 24...S/R valve operation logic circuit. Applicant's agent Hisashi Hatano, 20 Figure 3 Figure 4

Claims (1)

[Claims] 1. When the reactor pressure rises transiently, the pressure rise inside the reactor is suppressed by blowing out the steam inside the reactor through the reactor pressure relief safety valve into the suppression pool water. In the reactor pressure relief safety valve blowout actuation device,
A reactor pressure relief safety valve comprising a selection circuit that sequentially operates a reactor pressure relief safety valve having a steam release port in a location where the water temperature of a suppression pool is low, out of a plurality of reactor pressure relief safety valves. Blowout actuator. 2. The above selection circuit includes a temperature comparison circuit that determines whether the detected water temperature is higher or lower, a certification circuit that determines the correspondence between the water temperature and the steam release port, and a reactor pressure control circuit that outputs an activation signal for the reactor pressure relief safety valve. A reactor pressure relief safety valve blow-off actuating device according to claim 1, comprising a relief safety valve logic circuit.