JPH0712991A - Stopping apparatus for emergency electrically-driven valve of safety system for reactor - Google Patents

Abstract

PURPOSE:To fulfill both a function of a nuclear reactor safety system and protection of properties, by selecting a function priority or a protection priority depending on the operating condition of an electric motor for an emergency electrically-driven valve. CONSTITUTION:There are arranged two stopping conditions in the controlling direction of an electric motor 5 for an emergency electrically-driven valve. More specifically, when a nuclear reactor is turned abnormal, a parallel circuit of a torque switch 6ab and a limit switch 7ab, and a parallel circuit of a torque switch 6bb and a limit switch 7bb are used and, the operation is stopped if both switches hold an AND condition. At a test driving, the operation is stopped by a series circuit of a torque switch 6aa and a limit switch 7aa or a series circuit of a torque switch 6ba and a limit switch 7ba if either of the switches satisfies an OR condition. The operating condition of the electric motor 5 is decided from the combination of relay contacts 9a, 10a and that of relay contacts 9b, 10b switched between when the nuclear reactor is abnormal and at the time of the test driving, whereby the stopping condition of the electric motor 5 is controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an emergency electric valve stop device for a nuclear reactor safety system, and particularly to a nuclear reactor safety system suitable for mechanically protecting an emergency electric valve motor from its overload. The present invention relates to an emergency electric valve stop device.

[0002]

2. Description of the Related Art As conventional techniques for overload protection of this type of electric motor, there are techniques described in, for example, JP-A-60-162415 and JP-A-2-299404.

In the prior art described in Japanese Patent Laid-Open No. 60-162415, the signal contact during the simulated signal input is assembled in the control circuit for overload protection at the same time as the simulated input of the accident signal during the system maintenance test. The signal contact enables the overload protection circuit to operate during the system maintenance test.

Further, in the prior art disclosed in Japanese Patent Laid-Open No. 2-299404, the wiring breaker and the auxiliary contact of the overload relay are connected in series as a b contact, and a delay circuit is provided in parallel with the coil of the auxiliary relay. The auxiliary relay's a contact is connected in series with the operation circuit of the control circuit to prevent the circuit from malfunctioning due to vibration.

[0005]

By the way, in the conventional stop device for the emergency motor-operated valve of the reactor safety system, the overload protection of the motor for the emergency motor-operated valve is performed during the test operation, and the overload is protected when the reactor malfunction occurs. I try not to protect
At the same time, the property of the motor for the emergency electric valve during the test operation is protected and the function of the safety of the reactor in the event of a reactor abnormality is achieved.

On the other hand, in the case of an emergency electric valve, since it operates by generating the torque required for opening and closing for a very short time required for opening and closing, a torque switch for detecting overtorque and an opening and closing position are provided. By the limit switch to detect,
A stop command is issued mechanically.

However, in the prior art, the safety function of the reactor is prioritized for the emergency motor-operated valve required when a reactor abnormality occurs, and the stop condition is detected by detecting the open / closed position of the emergency motor-operated valve by the limit switch. In addition, the emergency electric valve is stopped when both of the stop conditions due to overtorque by the torque switch are satisfied, and by any chance during test operation,
If the emergency motor-operated valve stops at the intermediate position, the mechanical stop condition will not be satisfied, and it will be forced to operate until the electrical protection device operates, causing damage to the emergency motor-operated valve. There was a fear.

An object of the present invention is to protect the function and property of the reactor safety system by selectively using the function priority and the property priority for the motor for the emergency electric valve that is driven at the time of occurrence of a reactor abnormality and at the time of test operation. An object of the present invention is to provide an emergency motor-operated valve stop device for a reactor safety system that can achieve both of the above.

[0009]

Means for Solving the Problems The above-mentioned object is to provide a torque switch connected in series with a relay contact that is closed when a reactor abnormality occurs, and a limit switch connected in parallel with the torque switch, in the event of a reactor abnormality. When the AND condition of the opening operation of the torque switch that detects overtorque of the emergency electric valve and the opening operation of the limit switch that detects full opening and full closing of the emergency electric valve is met, the electric motor for the emergency electric valve is activated. The torque switch connected in series to the relay contact that configures the start-stop circuit to stop and closes during test operation, and the limit switch connected in series to this torque switch make the over-torque of the emergency electric valve during test operation. An OR condition is established between the opening operation of the torque switch for detecting the open state and the opening operation of the limit switch for detecting the fully open or fully closed state of the emergency electric valve. By configuring the start-stop circuit for stopping the motor for emergency electric valve when the is achieved.

Further, the above-mentioned object is to provide an overtorque during a test operation in a start / stop circuit for stopping the emergency electric valve motor when the overtorque of the emergency electric valve or the OR condition of full opening and full closing is satisfied during the test operation. This is achieved by connecting a new limit switch in parallel to the torque switch that opens when the torque is detected and configuring an overload protection device that prevents erroneous stoppage of the emergency electric valve due to overtorque detection during test operation.

Further, the above-mentioned object is to provide the emergency electric valve motor with an overload detector, and to connect an output contact to the overload protection device so that the emergency electric valve motor can operate during a test operation. When the overload operation is performed, the emergency electric valve motor is stopped by the overload protection device, and further, before the emergency electric valve motor reaches the overload operation, the emergency electric valve is overtorqued or fully opened or fully closed. This is achieved by configuring a circuit that stops the emergency motor-operated valve motor when the OR condition is satisfied.

The object is to provide a start / stop circuit for stopping the electric motor for the emergency electric valve when the overtorque of the emergency electric valve and the AND condition of full opening and full closing are satisfied when the abnormal reactor occurs, and a test operation. Sometimes, one relay contact that is opened during test operation is added to the start-stop circuit that stops the electric motor for the emergency electric valve when the over torque of the emergency electric valve or the OR condition of full opening and full closing is satisfied. This is achieved by combining the two start / stop circuits into a single circuit.

[0013]

According to the present invention, when a reactor abnormality occurs, an emergency electric motor is provided by the start / stop circuit composed of the torque switch connected in series to the relay contact opened during the test operation and the limit switch connected in parallel with the torque switch. When the AND condition of the opening operation of the torque switch that detects overtorque of the valve and the opening operation of the limit switch that detects full opening and full closing of the emergency electric valve is satisfied, the emergency electric valve motor is stopped, Prioritize the functions of the reactor safety system. Also, during the test operation, the start / stop circuit composed of the torque switch connected in series with the relay contact that is closed during the test operation and the limit switch connected in series with this switch detects overtorque of the emergency electric valve. When the OR condition of either the opening operation of the torque switch or the opening operation of the limit switch that detects whether the emergency motor-operated valve is fully opened or fully closed, the emergency motor-operated valve motor is stopped and the emergency motor-operated valve is stopped. And prevent damage to the motor for emergency electric valves and prioritize property protection.

As described above, according to the present invention,
By selectively using function priority and property protection priority,
It is possible to achieve both functions of the reactor safety system and property protection.

Further, according to the present invention, the overload protection device
It is possible to prevent erroneous stoppage of the emergency electric valve due to overtorque detection during starting and stopping of the emergency electric valve during test operation.

Further, according to the present invention, the emergency electric valve motor is overloaded during the test operation by the overload detector provided in the emergency electric valve motor and the output contact connected to the overload protection device. Even before reaching, the emergency electric valve motor can be stopped when the overtorque of the emergency electric valve or the OR condition of full opening and full closing is satisfied.

Further, in the present invention, by adding one relay contact which is opened during the test operation, the two start / stop circuits can be integrated into a single circuit, so that the entire apparatus can be made compact.

[0018]

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

FIG. 1 is a circuit diagram showing a first embodiment of the present invention, and FIG. 5 is an explanatory diagram showing valve opening conditions of an emergency electric valve.

The first embodiment shown in FIG. 1 is 480V.
It is applied to an AC motor-driven valve driven by a three-phase power supply, and an emergency motor-operated valve motor control panel 1, an emergency motor-operated valve 4 to be controlled, and an emergency motor-operated valve 4 for operating the emergency motor-operated valve 4 are operated. The electric motor 5 for electric valves, the operation panel 13, and the control center 14 are provided.

The emergency motor-operated valve motor control panel 1 is provided with an AC power supply 3φ and a contact switch 12 which is closed by an automatic start signal issued when an abnormality occurs in the motor-operated valve opening side reactor.
a, a motor-operated valve-opening contactor coil 2a, a motor-operated valve-opening contactor 3a, a contact switch 12b that is closed by an automatic start signal generated when a reactor abnormality in the motor-operated valve closing side, and a motor-operated valve closing operation Hour contactor coil 2
b and a contactor 3b at the time of electric valve closing operation.

The control center 14 has a relay operation contact 9a during motor valve opening operation and a test operation, and a relay operation contact 10a during motor valve opening operation and a test operation, and during motor valve closing operation and test operation. It has a closing operation relay contact 9b and an opening operation relay contact 10b during a motor drive valve closing operation and during a test operation.

The emergency electric valve 4 includes, in addition to the electric motor 5 for the emergency electric valve, a torque switch 6aa which is opened when an excessive torque is detected during a test operation during the electric valve opening operation.
A limit switch 7aa that opens when the motor-operated valve fully open position is detected during the motor-operated valve opening operation during test operation, and a torque switch 6ab that opens when the over-torque is detected when a reactor abnormality occurs during the motor-operated valve opening operation. A limit switch 7ab that opens when the motor-operated valve fully open position is detected when a reactor abnormality occurs during the opening operation, and a torque switch 6b that opens when an overtorque is detected during the test operation during the motor-operated valve closing operation.
a, a limit switch 7ba that opens when the motor-operated valve fully closed position is detected during the test operation during the motor-operated valve closing, and a torque switch 6bb that opens when overtorque is detected during the reactor abnormal operation during the motor-operated valve closing operation. And during the motor valve closing operation,
It has a limit switch 7bb that opens when the fully closed position of the motor-operated valve is detected when a reactor abnormality occurs.

The operation panel 13 has a manual operation switch 11a for the electric valve opening operation direction during the test operation and a manual operation switch 11b for the electric valve closing operation direction during the test operation.

Of the devices that operate during the motor-operated valve opening operation, the contactor 3a during the motor-operated valve opening operation is a contactor for opening and closing the power source, and is inserted between the emergency motor-operated valve motor 5 and the AC power source 3φ and connected. Has been done. The test operation close operation relay contact 9a and the test operation open operation relay contact 10
a is a relay contact that switches depending on the operating conditions of the emergency electric valve motor 5, the closing contact relay contact 9a during the test operation is an a contact that closes during the test operation, and the opening operation relay contact 10a during the test operation is during the test operation. This is the b contact that opens. The test operation closing operation relay contact 9a and the test operation opening operation relay contact 10a constitute a parallel circuit and are connected in series with the motor-operated valve opening operation contactor coil 2a.
At the test operation closing operation relay contact 9a, a torque switch 6aa that opens when an overtorque of the emergency electric valve 4 is detected, and as shown in FIG.
% Limit switch 7a that opens when it detects the open position
and a are connected in series. A torque switch 6ab that opens when an overtorque of the emergency motor-operated valve 4 is detected at the open-operation relay contact 10a during the test operation, and a 100% open position of the emergency motor-operated valve 4 is detected as shown in FIG. Then, the parallel circuit of the limit switch 7ab which is opened is connected. Further, the manual operation switch 11a of the emergency electric valve 4 used during the test operation in the operation panel 13 and the contact switch 12a which is closed by an automatic start signal issued when a reactor abnormality occurs are both valve operation opening side switches. is there.

In the above construction, when a reactor abnormality occurs, the open-operation relay contact 10a during test operation, that is, the relay contact that operates when a reactor abnormality occurs, is closed, and the close-operation relay contact 9a during test operation is open. Therefore, the contactor coil 2a during the motor-operated valve opening operation is excited through the parallel circuit of the torque switch 6ab and the limit switch 7ab, whereby the contactor 3a during the motor-operated valve opening operation is closed,
The emergency electric valve motor 5 operates. At this time, the emergency electric valve motor 5 is stopped by the torque switch 6a that forms an AND condition with the test operation open operation relay contact 10a.
AND of the opening operation of b and the opening operation of the limit switch 7ab
It is when the conditions are met.

On the other hand, during the test operation, the closing operation relay contact 9a during the test operation is closed, and the opening operation relay contact 10 during the test operation is performed.
Since a is open, the contactor coil 2a during the motor-operated valve opening operation is excited via the series circuit of the torque switch 6aa and the limit switch 7aa, whereby the contactor 3a during the motor-operated valve opening operation is closed, and the emergency motor-operated motor for valve motor. 5 works. At this time, the stop of the emergency electric valve electric motor 5
It stops even if either of the OR conditions of the opening operation of the torque switch 6aa and the opening operation of the limit switch 7aa forming the AND condition with the relay contact 9a is satisfied.

As described above, according to the first embodiment, the two stop conditions at the time of the abnormal operation of the motor operated valve and the occurrence of the abnormality of the reactor and the test operation are set as follows. By switching using the opening operation relay contact 10a, it is possible to switch between the test operation and the stop condition at the time of the occurrence of a reactor abnormality. Therefore, during the test operation, the torque switch 6aa which opens when the overtorque of the emergency electric valve 4 is detected. When the 100% open position of the emergency motor-operated valve 4 is detected, either of the limit switches 7aa, which operates to open, is established, so that the emergency motor-operated valve motor 5 is disconnected from the power source. The valve 4 can be protected from burning.

On the other hand, when a reactor abnormality occurs, the emergency electric valve motor 5 required for plant safety is forcibly operated, and the torque switch 6ab that opens when an overtorque of the emergency electric valve 4 is detected, and the emergency switch When the 100% open position of the motor-operated valve 4 is detected, the conditions of both switches of the limit switch 7ab that are opened are satisfied, so that the emergency motor-operated valve electric motor 5 is disconnected from the power source. Can be protected.

Further, during the motor-operated valve closing operation, the motor-operated valve closing operation contactor 3b is a contactor for opening and closing the power source, and, like the motor-operated valve opening operation contactor 3a, is connected between the emergency motor-operated valve motor 5 and the AC power supply 3φ. Is inserted and connected to. The test operation close operation relay contact 9b and the test operation open operation relay contact 10b are relay contacts that are switched depending on the operation conditions of the emergency electric valve motor 5, and the test operation close operation relay contact 9b is closed during the test operation. The open a contact and the open operation relay contact 10b during the test operation are open contacts during the test operation. The test operation closing operation relay contact 9b and the test operation opening operation relay contact 10b constitute a parallel circuit, and the motor-operated valve closing operation contactor coil 2b.
Are connected in series. At the test operation closing operation relay contact 9b, a torque switch 6ba that opens when an excessive torque of the emergency electric valve 4 is detected, and a 100% closed position of the emergency electric valve 4 are detected as shown in FIG. Then, the limit switch 7ba that opens is connected in series. At the test operation open operation relay contact 10b, there are a torque switch 6bb that opens when an over torque of the emergency electric valve 4 is detected and a limit switch 7bb that opens when a 100% closed position of the emergency electric valve is detected. Parallel circuits are connected. In addition, a manual operation switch 11b for the electric valve closing operation direction of the emergency electric valve 4 used during the test operation in the operation panel 13, and a contact point that is closed by an automatic start signal issued when an abnormality occurs in the electric valve closing operation side reactor. The switches 12b are both motor-operated valve operation closing direction side switches.

In the above construction, when a reactor abnormality occurs, the test operation open operation relay contact 10b, that is, the relay contact that operates when the reactor abnormality occurs, is closed, and the test operation close operation relay contact 9b is open. Therefore, the contactor carp 2b is excited during the electric valve closing operation via the parallel circuit of the torque switch 6bb and the limit switch 7bb,
As a result, the contactor 3b is closed during the electric valve closing operation, and the emergency electric valve electric motor 5 operates. At this time, the emergency electric valve motor 5 is stopped by opening the relay contact 1 during the test operation.
This is when the AND condition of the opening operation of the torque switch 6bb and the opening operation of the limit switch 7bb that form an AND condition with 0b is satisfied.

On the other hand, during the test operation, the closing contact relay contact 9b during the test operation is closed, and the opening operation relay contact 10 during the test operation is performed.
Since b is open, the contactor coil 2b during the motor-operated valve closing operation is excited via the series circuit of the torque switch 6ba and the limit switch 7ba, whereby the contactor 3b during the motor-operated valve closing operation is closed, and the motor for the emergency motor-operated valve is driven. 5 works. At this time, the stop of the emergency electric valve electric motor 5
It stops even if either of the OR conditions of the opening operation of the torque switch 6ab and the opening operation of the limit switch 7ab that form an AND condition with the relay contact 9b is satisfied.

As described above, according to the first embodiment, the two stop conditions at the time of the abnormal operation of the motor-operated valve and the abnormal operation of the reactor and the test operation are set as follows. By switching using the opening operation relay contact 10b, it is possible to switch the stop condition during the test operation and when the reactor abnormality occurs. 6ba and the limit switch 7ba that opens when the 100% closed position of the emergency electric valve 4 is detected, the emergency electric valve electric motor 5 is disconnected from the power source. The electric valve 4 can be protected from burning.

On the other hand, when an abnormal reactor occurs, the emergency electric valve motor 5 required for plant safety can be forcibly operated, and the torque switch 6bb that opens when an overtorque of the emergency electric valve 4 is detected, and the emergency When the 100% closed position of the motor-operated valve 4 is detected, the conditions of both switches of the limit switch 7bb that are opened are satisfied, so that the emergency motor-operated valve electric motor 5 is disconnected from the power source. Can be protected.

Next, FIG. 2 is a circuit diagram showing a second embodiment of the present invention.

In the second embodiment shown in this figure, the emergency electric valve 4 is provided with limit switches 8a and 8b.

The limit switch 8a constitutes a parallel circuit with the torque switch 6aa which opens when an overtorque is detected during the test operation during the motor-operated valve opening operation. The start and stop due to the excessive torque of 5 is prevented.

The limit switch 8b constitutes a parallel circuit with the torque switch 6ba which is opened when an excessive torque is detected during the test operation during the motor-operated valve closing operation. The start and stop due to the excessive torque of 5 is prevented.

Generally, when a motor-operated valve is opened / closed, the
As shown in, over torque is applied at the time of valve start and valve end. Due to this overtorque, the limit switches 6aa, 6b
When a operates, the emergency electric valve electric motor 5 is stopped.

The function of the limit switch 8a is such that even if the torque switch 6aa operates due to overtorque at the time of valve start and the emergency electric valve motor 5 is put into a start / stop state, the contact of the limit switch 8a is brought about. The circuit bypasses the torque switch 6aa so that the emergency electric valve motor 5 can be started.

On the other hand, the function of the limit switch 8b is that the torque switch 6b is operated by over torque during the motor-operated valve closing operation.
Even if ba operates and the emergency motor-operated valve electric motor 5 is in a start / stop state, the contact circuit of the limit switch 8b bypasses the torque switch 6ba, so that the emergency motor-operated valve motor 5 can be started. I am able to do it.

As described above, according to the second embodiment, the torque switch 6aa that opens when an overtorque is detected during the motor-operated valve opening operation and the test operation, and the emergency motor-operated valve motor 5 at this time. Parallel circuit with the limit switch 8a for preventing starting and stopping due to over torque, a torque switch 6ba that opens when an over torque is detected during the test operation during the motor valve closing operation, and the emergency motor valve motor 5 at this time. The parallel circuit with the limit switch 8b that prevents the start / stop of the emergency electric valve 4 due to overtorque can protect the start / stop of the emergency electric valve motor 5 due to the overtorque of the emergency electric valve 4 during the test operation.

The other structure and operation of the second embodiment are the same as those of the first embodiment.

Next, FIG. 3 is a circuit diagram showing a third embodiment of the present invention.

In the third embodiment shown in this figure, the second
This embodiment is constructed by combining the overload detector 16 of the overload protection device for the emergency electric valve electric motor 5 and the output contacts 15a and 15b thereof.

The output contact 15a is connected during the motor-operated valve opening operation,
Closing operation relay contact 9a during test operation and torque switch 7
A series circuit is configured via aa, 6aa and the limit switch 8a, and a parallel circuit is configured with the test operation open operation relay contact 10a.

The output contact 15b is connected during the motor-operated valve closing operation,
Trial operation closing contact relay contact 9b and torque switch 7
A series circuit is configured via ba, 6ba and the limit switch 8b, and a parallel circuit is configured with the test operation open operation relay contact 10b.

When the emergency motor-operated valve motor 5 is overloaded during a reactor abnormality, the overload detector 16 operates, the output contact 15a opens, and the test operation open operation relay contact 10a opens. Other than the time, that is, when the reactor is abnormal, it is closed, so the motor-operated valve contactor 2a continues to be excited during the test operation, and the emergency motor-operated valve motor 5 continues to be forcibly operated, but the torque switch 6ab and the limit When the AND condition of the switch 7ab is satisfied, the emergency electric valve motor 5 is stopped.

When the emergency motor-operated valve motor 5 is overloaded during the test operation, the overload detector 16 operates and the output contact 15a opens as in the case of a reactor abnormality, but the open operation during the test operation occurs. Since the relay contact 10a is also opened during the test operation, the contactor coil 2a is not excited during the motor-operated valve opening operation, and the emergency motor-operated valve motor 5 is stopped. Also,
Before the emergency electric valve electric motor 5 reaches the overload operation, the emergency electric valve electric motor 5 stops even if any of the OR conditions of the torque switch 6aa and the limit switch 7aa is satisfied.

Further, when the emergency electric motor 5 for the electric motor valve is overloaded during the operation of the motor-operated valve closing when the reactor malfunctions, the overload detector 16 operates to open the output contact 15b and open during the test operation. Since the operation relay contact 10b is closed when a reactor abnormality occurs, the cotteractor coil 2b continues to be excited during the test operation during the motor-operated valve closing operation, and the emergency motor-operated valve electric motor 5 continues to be forcedly operated, but the torque is reduced. Switch 6bb
When the AND condition of the limit switch 7bb is satisfied, the emergency electric valve motor 5 is stopped.

In addition, during the test operation, the overload detector 16 operates and the output contact 15b opens, but the closing operation relay contact 10b also opens during the test operation, as in the case of the reactor abnormality. During the closing operation, the octactor coil 2b is not excited, and the emergency electric valve motor 5 stops. Furthermore, before the emergency electric valve electric motor 5 reaches the overload operation, the emergency electric valve electric motor 5 is stopped even if either OR condition of the torque switch 6ba and the limit switch 7ba is satisfied.

As described above, according to the third embodiment, the emergency electric valve electric motor 5 is overloaded during the test operation by using the emergency electric valve electric motor 5 overload protection device. When the overload detector 16 operates and the output contact 15a of the overload detector 16 opens during the motor valve opening operation, and the OR condition of the torque switch 6aa and the limit switch 7aa is satisfied, the motor valve closing operation also starts. The output contact 15b of the overload detector 16 is opened, and the torque switch 6ba and the limit switch 7ba are turned off.
When the R condition is satisfied, the emergency motor-operated valve 4 can be double protected mechanically and electrically.

The other structure and operation of the third embodiment are the same as those of the second embodiment.

Further, FIG. 4 is a circuit diagram showing a fourth embodiment of the present invention.

In the fourth embodiment shown in this figure, the first
In the third embodiment, the test operation open operation relay contact 10a during the electric valve opening operation and the test operation open operation relay contact 10b during the electric valve closing operation are each 1
Only by adding one by one, the function of the emergency motor-operated valve stop device is not changed, and it is configured as one circuit. As a result, one torque switch and one limit switch can be reduced.

As described above, according to the fourth embodiment, in the above-described first to third embodiments, the two systems for the reactor abnormality occurrence and the test operation are configured by respective circuits. , Open operation during test operation Only by adding one relay contact 10a, 10b without changing the function of the emergency electric valve stop device 1
By using the circuit, it is possible to reduce one torque switch and one limit switch, and it is possible to control the stop condition of the emergency electric valve 4 at the time of the occurrence of a reactor abnormality and at the time of test operation.

[0057]

【The invention's effect】

(Claim 1) The torque switch connected in series to the relay contact that closes when a reactor abnormality occurs, and the limit switch connected in parallel to this torque switch prevent overtorque of the emergency electric valve when a reactor abnormality occurs. A start-stop circuit is configured to stop the motor for emergency electric valve when the AND condition of the opening operation of the torque switch for detection and the opening operation of the limit switch for detecting full opening and full closing of the emergency electric valve is satisfied. The opening operation of the torque switch that detects the over-torque of the emergency electric valve during the test operation by the torque switch that is connected in series with the relay contact that is closed during the test operation and the limit switch that is connected in series with the torque switch When the OR condition between the open operation of the limit switch that detects full open and full close of the emergency electric valve is satisfied, The constitutes a start-stop circuit for stopping, by selectively using function priority and property protection preferences by the operating conditions, the effect of obtaining achieving the function of the reactor safety system, the compatibility of the property protection.

(Claim 2) Over torque during the test operation in the start / stop circuit for stopping the emergency electric valve motor when the over torque of the emergency electric valve or the OR condition of full opening and full closing is satisfied during the test operation. The new limit switch is connected in parallel to the torque switch that opens when
An overload protection device is configured to prevent erroneous stoppage of the emergency motorized valve due to overtorque detection during test operation. This has the effect of preventing accidental stoppage.

(Claim 3) The emergency electric valve motor is provided with an overload detector for the emergency electric valve motor, and an output contact is connected to the overload protection device. When the overload operation is performed, the emergency electric valve motor is stopped by the overload protection device, and further, before the emergency electric valve motor reaches the overload operation, the emergency electric valve is overtorqued or fully opened or fully closed. A circuit is configured to stop the emergency motor-operated valve motor when the OR condition is satisfied. Even before the emergency motor-operated valve motor is overloaded during the test operation, the emergency motor valve overtorque or There is an effect that the emergency motor-operated valve motor can be stopped when the OR condition of fully open and fully closed is satisfied.

(Claim 4) A start / stop circuit for stopping the electric motor for the emergency electric valve when the overtorque of the emergency electric valve and the AND condition of full opening and full closing are satisfied when the abnormal reactor occurs, and a test operation. Sometimes, one relay contact that is opened during test operation is added to the start-stop circuit that stops the electric motor for the emergency electric valve when the over torque of the emergency electric valve or the OR condition of full opening and full closing is satisfied. Since the two start-stop circuits are combined into a single circuit, the two start-stop circuits are combined into a single circuit, which has the effect of making the entire apparatus compact.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a first embodiment of the present invention.

FIG. 2 is a circuit diagram showing a second embodiment of the present invention.

FIG. 3 is a circuit diagram showing a third embodiment of the present invention.

FIG. 4 is a circuit diagram showing a fourth embodiment of the present invention.

FIG. 5 is an explanatory diagram showing valve opening conditions of the emergency electric valve in the first to fourth embodiments.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electric motor control panel for emergency electric valve 2a ... Contactor coil during electric valve opening operation 2b ... Contactor coil during electric valve closing operation 3a ... Contactor during electric valve opening operation 3b ... Contactor during electric valve closing operation 4 ... emergency motor-operated valve, 5 ... emergency motor-operated valve motor, 6aa ... motor-operated valve opening operation, torque switch that opens when overtorque is detected during test operation, 6
ab ... torque switch that opens when an overtorque is detected when a reactor abnormality occurs during the motor-operated valve opening, 6ba ... torque switch that opens when an overtorque is detected during a test operation during motor-operated valve closing, 6bb ... a motor-operated valve Torque switch that opens when overtorque is detected when a reactor abnormality occurs during closing operation, 7aa ... Limit switch that opens when the motor-operated valve fully open position is detected during motor-operated valve opening operation, test operation, 7a
b ... Limit switch that opens when the motor-operated valve fully-open position is detected when a reactor abnormality occurs during the motor-operated valve opening operation, 7ba ...
Limit switch that opens when the motor-operated valve fully-closed position is detected during test operation during motor-operated valve closing, 7bb ... Limit switch that opens when the motor-operated valve fully-closed position is detected when a reactor abnormality occurs during motor-operated valve closing operation, 8a ... during motor operated valve opening operation,
Limit switch for preventing start / stop of the emergency electric valve motor due to overtorque, 8b ... Limit switch for preventing start / stop of the emergency electric valve motor due to overtorque, 9a ... Electric valve opening operation Medium, test operation closing operation relay contact, 9b ... motor valve closing operation, test operation closing operation relay contact, 10a ... motor valve opening operation, test operation opening operation relay contact, 10b ... motor valve closing operation, Open operation relay contact during test operation, 11a ... Manual operation switch for electric valve opening operation direction during test operation, 11b ... Manual operation switch for electric valve closing operation direction during test operation, 12a ... Electric valve opening operation side, reactor abnormality occurs A contact switch that is closed by an automatic start signal sometimes issued, 12b ... A motor-operated valve closing side, a contact switch that is closed by an automatic start signal issued when a reactor abnormality occurs, 3 ... operation panel, 14 ... control center, 15a ... electric valve opening operation side, the output contacts of the motor overload detector for emergency electric valves, 15b ... electric valve closing operation side,
Output contact of motor overload detector for emergency electric valve, 16 ...
Electric motor overload detector for emergency electric valves.

Claims (4)

[Claims] 1. An electric motor for an emergency electric valve that is driven when a reactor abnormality occurs and during a test operation, a contactor for opening and closing a power supply to the electric motor for an emergency electric valve, and the emergency electric valve. Torque switch that opens by detecting overtorque of the electric motor, limit switch that opens at the fully opened position of the emergency electric valve, contact switch that closes by an automatic start signal issued when a reactor abnormality occurs, emergency electric valve during test operation A torque switch connected in series with a manual operation switch for opening and closing, a relay contact that opens during a test operation and closes when a reactor abnormality occurs, and a relay contact that closes during a test operation, and that closes when a reactor abnormality occurs And a limit switch connected in parallel with this torque switch to detect the torque of the emergency electric valve when a reactor abnormality occurs. A. Opening operation of the switch and opening operation of the limit switch that detects full opening and closing of the emergency motorized valve A
A torque switch connected in series to the relay contact, which constitutes a start / stop circuit for stopping the emergency electric valve motor when the ND condition is satisfied, and which is closed during test operation, and a limit connected in series to this torque switch. When the OR condition of the opening operation of the torque switch that detects the over-torque of the emergency electric valve during the test operation and the opening operation of the limit switch that detects full opening and full closing of the emergency electric valve is satisfied by the switch An emergency motor-operated valve stop device for a reactor safety system, comprising a start-stop circuit for stopping an electric motor for an emergency motor-operated valve. 2. Over torque is detected during a test operation in a start / stop circuit that stops the emergency electric valve motor when the over torque of the emergency electric valve or the OR condition of fully open and fully closed is satisfied during the test operation. The overload protection device configured to connect a new limit switch in parallel to the torque switch that is opened at this time to prevent erroneous stoppage of the emergency electric valve due to overtorque detection during test operation.
Emergency motorized valve stop device for the nuclear reactor safety system described. 3. The emergency electric valve motor is provided with an overload detector for the emergency electric valve motor, and an output contact is connected to the overload protection device so that the emergency electric valve motor is overloaded during a test operation. Then, the emergency motor-operated valve motor is stopped by the overload protection device, and before the emergency motor-operated valve motor reaches overload operation, an overtorque of the emergency motor-operated valve or an OR condition of full opening and full closing is set. The emergency motor-operated valve stop device for a nuclear reactor safety system according to claim 2, wherein a circuit for stopping the motor for the emergency motor-operated valve when it is established is configured. 4. A start-stop circuit for stopping the electric motor for the emergency electric valve when overtorque of the emergency electric valve and AND conditions of full opening and full closing are satisfied when the reactor abnormality occurs.
Add one relay contact that opens during the test operation to the start-stop circuit that stops the motor for the emergency electric valve when the over torque of the emergency electric valve or the OR condition of full opening and full closing is satisfied during the test operation. The emergency motor-operated valve stop device for a reactor safety system according to any one of claims 1 to 3, wherein the two start-stop circuits are combined into a single circuit.