JPS6033085A - Controller for control rod of nuclear reactor - 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 The present invention relates to a nuclear reactor control rod control device, and in particular, to a control rod control device used for controlling thermal output of a nuclear reactor and shutting down a nuclear reactor.
The present invention relates to a control device for a control rod drive mechanism used for insertion into or withdrawal from a nuclear reactor.

FIG. 1 shows a simplified structure of a magnetic jack type drive mechanism for nuclear reactor control rods. In the figure, three coils are installed outside the reactor pressure vessel: a lift coil l, a movable gripper coil (hereinafter referred to as MG coil), and a stationary gripper coil (hereinafter referred to as SG coil). Operate the excitation armature that is set. That is, the mover pull gripper armature and the stationary gripper armature actuate latches 7 and g that engage with the troughs or grooves Xa of the control rod drive shaft t, respectively, when the MG coil λ and the SG coil 3 are energized. A stationary latch g is used to hold the control rod drive axle in a certain position. The movable latch 7 is raised and lowered by the lift armature 9 when the lift coil l is excited, and raises the control rod drive shaft 6 (moves in the withdrawal direction).
Used to lower (move in the insertion direction).

In addition, /a is a lift magnetic pole, 3a is a stationary gripper magnetic pole, 5 is a stationary gripper armature, ? f
i is a movable latch link, and A'a is a stationary latch link. Figure XX shows the operation sequence of the control rod drive mechanism. In Fig. 2, corresponding parts in Fig. 1 are represented by the same symbols, but are they movable latches? and the stationary latch g are shown in a simplified manner.

The control rod withdrawal sequence and insertion sequence will be described below with reference to FIGS. 1 and 2.

A: Withdrawal sequence (a) In the standby state, the SG coil J is energized and the stationary latch g is closed to hold the control rod drive shaft [states shown in Figures 2 (a) to (a)]. l Energize the MG coil coil and close the movable latch 7 [Fig. 2 (a)-f)] (/→ Demagnetize the SG coil A1.7 and release the stationary latch g [Fig. 2 ( a
) −r → state]) Excite the lift coil l to operate the lift armature and raise the movable gripper armature ada.This moves the control rod drive shaft t supported by the movable latch 7 into the groove 6a of the control rod drive shaft. 7
Raise the stationary latch g in the direction of the arrow by the same amount as shown in Fig. 2 (al-).
Close [Figure 2 (al-((e) state)] (to)
Demagnetize the MG coil λ and release the movable latch 7 [state shown in Fig. 2 (a)-(to)] ())! Jy) Demagnetize the coil l and lower the lint armadure 9 in the direction of the arrow [states shown in FIG. 2(a)-(g)] (g) Repeat the operations from (b) to (g).

B: Insertion sequence j a) In the standby state, the SG coil 3 is energized, the stationary latch g is closed, and the control rod drive mechanism is held [state shown in Fig. 2 (b) - + a)] ( (b) Excite the lift coil / to raise the lift armature t in the direction of the arrow (Fig. 2 (b) - i)] (c) Excite the MG coil A/2 to raise the lift armature t in the direction of the arrow. 7
Close the door 7 [to the state shown in Figure 2 (b)-(c)]
Demagnetize the SG coil 3 and release the stationary latch S. .Now, lower the control rod drive shaft 6 by seven grooves 6a in the direction of the arrow [Fig. 2(b) - (state 711)] (to) Excite the SG coil 3 and release the stationary latch g. Close with [Figure 2 (b)-(to) state] () IM
() Demagnetize coil 2 and moveable grip latch 7
[state of Figure 2 (b) - (g)] (Repeat the operations from (b) to (g).

As mentioned above, the operation of inserting or withdrawing the control rods into the reactor is performed by sequentially supplying DC current to the three types of coils of the control rod drive mechanism: the SG coil, the MO coil, and the lift coil. A sharpener that does not drive the rod is
It is held in a fixed position by continuing to excite the SG coil. Here, when the control rod is not driven [Fig. 2 (a)
l and (b) - (a)] excite the SG coil;
It is important to note that the control rods would fall into the reactor if the

The control rod controller supplies direct current to the three types of coils in the control rod drive mechanism. Conventionally, there has been a device of this type as shown in FIG. In the figure, loads lθ, 20 and 30 respectively correspond to the three coils of the control rod drive mechanism described above. That is, the load 10 corresponds to the SG coil of a plurality of control rod drive mechanisms, the load 30 corresponds to the MG coil of a plurality of control rod drive mechanisms (Rrl), and the load 30 corresponds to the MG coil of a plurality of control rod drive mechanisms. Corresponds to a lift coil. Each load consists of three groups of loads. That is, the first set of loads IO consists of the SG coils of the first group 12, the second group / 4' and the third group / 6. The 3rd group /2゜/ri and /6 loads all require a DC sequence at the same level (when the SG coil is energized to hold the control rods), and the control rods are driven sequentially by group, but the control rods In order to hold the control rods in a fixed position even during periods when the control rods are not driven, it is necessary to energize the SG coils of all control rod drive mechanisms, so the switching operation is as follows for the second and third sets of loads. Not done.

Similarly, for the second group of loads -〇, the first group here, the second group 2Q,
and the third group consists of two MG coils.

The loads in each of these three groups all still require the same level of DC sequence, but with different excitation periods.

That is, all three groups of control rods are driven, but their driving times are different. Accordingly, the first group of control rods is driven by a first group of control rod drive mechanisms comprising a first group of SG coils, a first group of MG coils, and a first group of lift coils.

The first group of control rods is driven by a second group of control rod drive mechanisms including a second group of SG coils, MG coils, and lift coils. Similarly, the third group control rods are driven by a third group control rod drive mechanism.

The drive sequence for each group of control rods is performed as described above (2) by sequentially energizing the three types of coils of each control rod drive mechanism.

Three-phase power is supplied by three-phase power supply llo to multiple power units) #, 2. 6. It is supplied to θ, tacho, and sda. This electric kaninit supplies DC output at predetermined multi-level (usually three levels) values based on a reference current signal from a reference current source, which will be described later. The first 'Ei crab unit l12 is a single line ++ and a three-phase power supply line θ through the line shown in the figure.
Receives three-phase power from. The first electric crab unit 4t is an electric crab unit for providing a DC sequence to the lift coils of a plurality of control rod drive mechanisms. The output of the λth λ of the three-phase power supply lθ is connected to the line 11. It is supplied to the second electric crab unit lI6 through g. The third power unit A is an electric unit for providing direct current to the MG coils of the plurality of control rod drive mechanisms. Three-phase power is supplied from a third output signal 9 from the three-phase power supply q6 to three separate units 30, 32 and 30 through lines st, sg and 6θ, respectively.

The turtle crab units 5θ15.2 and 3'l are turtle crab units for providing direct current to the SO coils of the plurality of control rod drive mechanisms in a predetermined sequence, respectively.

Separate hO) for each load lU, /41' and lO)
'llJ.

The reason why crab units Sθ, 52 and sy are provided is that when a group of control rods is inserted or withdrawn during operation of the control rod drive device, the SG of the control rod drive mechanism of the remaining control rod group
This is because it is necessary to energize the coils to hold these control rods in a fixed position. For example, if the first group control rod drive mechanism is to be energized, i.e., the first group load (SG coil) 12 of the first group lθ, the first group load of the λ-th group −〇 (MC) coil) 22 and the load (lift coil) 32 of the first group of the third group 3θ is energized sequentially according to a predetermined DC sequence, the load of the second group and the third group of the first group lθ/4 This is because it is necessary to energize the control rods and/or B to prevent the control rods driven by these control rod drive mechanisms from falling into the reactor.

6.2 is typically divided into three levels: zero current value (the current value that demagnetizes the coil), low current value (the current value required to hold the control rod), and full current value (the current value that is required to keep the control rod in place). This is a well-known reference current source that generates in a predetermined sequence a reference current signal having a current value (current value required only when Direct current is supplied. Reference current 6
9. The first reference current signal is transmitted through the line A4' to the first electronic unit 41-. Supply to 2. The first reference current signal is used to regulate the DC output from the first power unit octopus, ie, the electric crab unit for the lift coil of the control rod drive mechanism. The DC output from the 7th power unit is the load 3.2 of the 1st, 1st, 1st, and 3rd groups.
, ,? Any of ll and 36/-':)
The output from the first electric capacitor II2 is selected by a first switching circuit A6 (e.g., controlled by an external bank selection circuit) such that it is not transmitted to the first electric circuit A6 via lines qg, go and g,2, respectively.

Similarly, the second reference 'tlC current signal from the reference current signal 2 is the T15 for the M and G coils of the plurality of control rod drive mechanisms.
゜The second electric crab knit that is a crab knit? Track 74 to A
'Supplied via. The DC output from the second unit is supplied to the first group switching circuit 76, and the first group, second group, etc.
Group and third group loads 22. ．． 2'l and 26, each line 6g.

DC is supplied via 70 and t2.

The reference current source 62 is connected to the third electric current source 62 by the lines gil, gt, and gg, each of which is a constant S() coil phase. ; Three male third reference current signal groups are supplied to the 0, 32, and 5 groups (however, reference current signals of the same DC level are supplied to all groups in the holding state). The reason why a separate third reference current signal group is supplied to these three electric control units is that when one group of control rods is inserted or withdrawn, the control rods of the remaining control rod groups This is because it is necessary to energize the SG coil of the drive mechanism to hold these control rods in a fixed position. In addition, the first and second
The electric controller may be configured as a thyristor type switch, and the first and second switching circuits may also be configured as a thyristor type switch device.

The conventional device is configured as described above (because it is SC in the control rod standby state), and if the excitation function of the coil ζ is lost, the control rod drive shaft cannot be held, and the control rod falls. The drawback was that in some cases, it could lead to reactor shutdown.

This invention was made to eliminate the drawbacks of the conventional ones as described above, and when the excitation function of the 8G coil is lost by the main electric bus unit, the failure detection section, the auxiliary countermeasure crab unit, and the first and first coil #ili auxiliary switching circuit allows
The purpose of this invention is to provide a device that can simultaneously selectively excite the SG coil and MG coil and hold the control rod. Elj, the excitation function of the SG coil and MG coil is doubled, making it a highly reliable device.

In order to achieve such an object, the lit child reactor control rod control device according to the present invention includes: a plurality of predetermined groups of lift coils; a first switching circuit that sequentially selects the lift coils of the plurality of predetermined groups at a predetermined cycle; a three-phase A reference current source that sequentially generates a plurality of reference levels/a DC current of a level based on the reference current signal is connected to the electric current source, and these are connected to a group of reference current sources through the first switching circuit. a first electric coil for supplying electricity to one-knot coils in the same number of groups as the predetermined plurality of groups; , 29J switching circuit; a first converting the Sanwa power supply into a direct current having a level based on the second reference current signal of the reference current source, and supplying this to a group of movable gripper coils via the first switching circuit; 2-electric crab knit: Stationary gripper coils of the same number of groups as the predetermined plurality of groups; and provided corresponding to the stationary gripper coils of the predetermined plurality of groups, respectively, to connect the three-phase power source to the predetermined current source from the reference current source. a third electrical circuit that converts each of the third reference current signal groups having a sequence into a DC current of a level based on a separate third reference current signal group and supplies the DC current to each of the predetermined plurality of groups of stationary lymph coils; λ and a third reference current signal, a group of control rods is inserted/extracted through each of the above-mentioned type crab units, and the third reference current signal group outside the insertion/extraction operation is applied to the third reference current signal group outside the insertion/extraction operation. In a nuclear reactor control rod control device that energizes the stationary gripper coil via a three-ton crab unit: an auxiliary electric cap unit connected to the three-phase power supply: a first auxiliary switch connected between the stationary gripper coil and the stationary gripper coil; A circuit; a second auxiliary switching circuit connected between the output terminal of the auxiliary vehicle crab knit and the movable gripper coil of either group; and an output terminal of each of the third electric crab knits, and an input of the auxiliary vehicle crab knit. a fault detection section connected to the terminal and each input terminal of the first and first sleeve switching circuits; When a failure occurs, this is detected and the first Sode assistant LJJ replacement circuit is selectively controlled so that the stationary gripper coil of the group corresponding to the failed plane crab unit is energized, and at the same time, the first Sode assistant LJJ replacement circuit is controlled to respond to the failure 'turtle crab unit'. The second auxiliary switching circuit is selectively controlled so that the movable gripper coil of the group is also excited, and at the same time, the auxiliary one hooker unit is supplied with a direct current necessary for holding the control rod. It cures a composition characterized by being something that does.

The present invention will be described below with reference to the embodiment shown in FIG. 7 of the accompanying drawings.

In FIG. 7, the difference from FIG. 3 is that the failure detection unit qo
, an auxiliary power unit q/, a first auxiliary switching circuit q/, and a second auxiliary switching circuit /θO1. The failure detection unit 90 is the third electric crab unit 30,! ;2 and sQ- output line 2. It is connected to input the current value signals from Tada and 9O. The failure detection unit 90 further includes a first auxiliary vehicle connected to the three-phase power source llo, and a first auxiliary vehicle connected between this and the SG coil load of any group.
It is connected to the auxiliary switching circuit 9 and the auxiliary switching circuit 9 is connected to the auxiliary switching circuit 9.
) is also connected to a second auxiliary switching circuit /θθ connected between the crab unit I// and the MG coil load of either group. The failure detection unit 90 includes a third power unit) 5θ,
5. When an abnormality is detected in the output current value of either 2 or 1+, for example, a failure in which no current flows is detected, the auxiliary 'torque unit' is activated, and at the same time, the first sode auxiliary switch circuit 9/ and the first sode auxiliary switch are activated. times km / /) tl V meeting f1?7
11τ notifies which output current of the unit S4t is abnormal, and thereby the first auxiliary switching circuit 9/ switches the output point 9g of the auxiliary power unit) to the faulty type crab unit go, s,;t, or sG coil load of the group corresponding to sda/2. The λth auxiliary switching circuit /θθ connects the output point 9g of the auxiliary vehicle Kaninit +/ to the faulty turtle Kaninit 5θ.

S2. Alternatively, it is switched and connected to the MG coil loads 22, 24' or rollers of the same group as the group corresponding to 1+. As the auxiliary power unit/unit, a Zyristor-type one provided as a backup for the third electric unit can be used, and although it is functionally almost the same as the third electric unit, it has a constant current control circuit configuration. It has a simpler constant voltage control circuit configuration, and the reference current signal from the reference current source 6 is not used. In addition, the first and second λ auxiliary switching circuits 9/
Similarly to the first and second switching circuits, the switching circuits 100 and 100 may also be configured as a switch device of the 3-wire type.

In this system, the control rod insertion/extraction function is no different from the conventional system, but if the excitation function of the SG coil holding the control rod is lost, this is detected and the supplementary measure Kannit 4 (/ It has a unique function of preventing the control rod from falling by exciting the SG coil and MG coil belonging to the same group.

For example, if the third electric crab unit SO fails and the current necessary to hold the control rods is no longer supplied to the SG coil load 12 of the first group of the first set IO, an abnormality in this current, that is, the absence of this current, is detected. The failure detection unit 10 detects from the output line 9.2, and the failure detection unit θ is connected to the Sanwa power supply terminal O via the line q5.
The three-phase power supply is rectified by the auxiliary power unit) +/ so that the SG coil load /, 2 and MG coil load 2- of the first group corresponding to the faulty unit are excited by the power supplied from the auxiliary power unit). And the first and the first auxiliary switching circuits respectively? / and 100 command to switch and connect the output line 9g of the auxiliary basket unit / to the output line 92 and the output 16ff. Therefore, even if the third electric power unit go fails and the stationary latch S (Fig. 1) attempts to open, the auxiliary power unit 5θ will be replaced by the first set θ and the second set 20. In order to supply the current necessary to hold the control rods to the SO coils/2 and MG coils 22, which are the loads of the first group, the control rods do not fall and are held at a certain position.

3rd Den Kani Knit! Even if a failure occurs in R, 2 or 5 Hiroshi, the control rods of the 2nd and 3rd groups can be maintained in the states shown in Figure a, fa) and (b)-(a), respectively, in the same manner as above. Needless to say.

As described above, according to the present invention, the current supplied to the first set of S() coil loads 10 is ! 4) Monitor the status and call for assistance if there is any abnormality)+! / is the first set of guards lO
At the same time, since the excitation current is supplied to the second set of loads θ, it is possible to prevent the control 41 from falling unnecessarily and to prevent unplanned shutdown of the nuclear reactor.

[Brief explanation of the drawing]

Figure 1 is a schematic cross-sectional view of the control rod drive mechanism in a nuclear reactor;
Figures 2 (a) and (b) are diagrams showing the operation sequence of the control rod drive mechanism, Figure 3 is a block diagram of a conventional reactor control rod control device, and Figure 2 is an example of the control rod drive mechanism. FIG. 2 is a block diagram of a nuclear reactor control rod control device according to the present invention. In the figure, 10 is the first set of load (SG coil), -〇 is the second set of load (MG coil), 30 is the third set of load (lift coil), qo is the three-phase power line, and Dako is the first power line. ,
l/6 is the second electric cylinder, Sθ, 32. and 5 are third electric circuits, 6 are reference current sources, A6 is the first switching circuit, 76 is the λ-th switching circuit, /, 2, 2.2. and 32 are the first group loads, /l, 2hiro and 3g are the second group loads, /l
, , 26° and 36 are the third group loads, t/ is the auxiliary countermeasure crab unit, 90 is the failure detection section, 91 is the first auxiliary switching circuit, i
oo is a first auxiliary switching circuit. In the drawings, the same reference numerals indicate the same or corresponding parts. Agent Makoto Kuzuno - Homura 1 Zuko 2 (Q) (Sho 1) (He) (G)

Claims (1)

[Claims] a predetermined plurality of groups of lift coils; a first switching circuit that sequentially selects one group of lift coils from the predetermined plurality of groups in a predetermined sequence; a first reference of a reference current source that sequentially generates a plurality of reference levels from a three-phase power supply; a first electric crab unit that converts the current signal into a direct current (level) and supplies it to a group of lift coils via the first switching circuit; movable gripper coils in the same number of groups as the predetermined plurality of groups; a switching circuit that sequentially selects one group of movable gripper coils from the plurality of groups in the predetermined sequence; converts the three-phase electric current into a direct current at a level based on a second reference current signal of the reference current source; A second electric crab unit supplies this to a group of movable gripper coils via the first switching circuit; stationary gripper coils of the same number of groups as the predetermined plurality of groups; and stationary gripper coils of the predetermined plurality of groups. the three-phase power supply is converted into a DC current of the predetermined level based on a respective group of separate third reference current signals having the predetermined sequence from the reference current source; a third electric crab unit that respectively supplies a plurality of groups of stationary gripper coils, and inserts and inserts a group of control rods through each of the city crab units based on the first, second, and third reference current signals.
While performing the extraction operation, the third
In a nuclear reactor control rod control device in which a group of reference current signals energizes the stationary gripper coil via the 713th crab unit outside of insertion/extraction operations: an auxiliary turtle crab unit connected to the three-phase power supply; a first auxiliary switching circuit connected between the output terminal of the crab knit and the stationary gripper coil of any group; a first auxiliary switching circuit connected between the output terminal of the auxiliary vehicle crab knit and the movable gripper coil of any group; a second auxiliary switching circuit connected; and a failure detection unit connected to the output terminal of each of the third electric crab units, the input terminal of the auxiliary vehicle crab unit, and each input terminal of the first and second auxiliary switching circuits; : The failure detection unit detects the 31st failure in which a DC output signal is not generated from any of the crab units, and energizes the stationary gripper coil of the group corresponding to the failure type crab unit. The first
selectively controlling the auxiliary switching circuit, and selectively controlling the third auxiliary switching circuit so that the movable gripper coil of the group corresponding to the failed crab unit is also excited; and at the same time, controlling the control rod holding from the auxiliary crab unit; A nuclear reactor control rod control device, characterized in that it controls so that a necessary direct current is supplied.