KR101899892B1 - Nuclear power plant safety system - Google Patents

Abstract

The present invention relates to a control system for a nuclear power plant, comprising at least two channels, a first abnormality controller of a different type, and a second abnormality controller And a second abnormality determination controller for generating a switching control signal according to the reactor abnormality signal and transmitting the switching control signal to the switching module. According to the switching control signal, when the reactor is normal, And a switching module for stopping the reactor when the reactor is abnormal.

Description

[0001] Nuclear power plant safety system [0002]

The present invention relates to a control system for a nuclear power plant, comprising at least two channels, a first abnormality controller of a different type, and a second abnormality controller And a second abnormality determination controller for generating a switching control signal according to the reactor abnormality signal and transmitting the switching control signal to the switching module. According to the switching control signal, when the reactor is normal, And a switching module for stopping the reactor when the reactor is abnormal.

Nuclear power generation refers to the generation of electricity by turning the turbine generator with steam generated by boiling water generated by the energy generated through the fission chain reaction. In atomic nuclei composed of protons and neutrons, nuclear energy is generated by the release of the energy required to completely separate the nucleons and make them free particles. Therefore, these nuclear power generation is the most suitable power source , And most countries in the world produce electricity using nuclear power.

However, in the case of nuclear power generation, the use of nuclear power is accompanied by a great deal of risk, so many safety devices and highly trained specialist controls are necessary.

Nuclear safety system consists of reactor protection system, related process protection system and power plant control system. In particular, nuclear reactor protection system is equipped with process control facility, Engine safety signal generation and related instrument operation can be performed.

At this time, when the reactor is operated, a single point of failure (SPV) may appear in the reactor protection system itself. Single Point Vulnerability (SPV) means a single fault vulnerability and is a trigger element that can stop a power plant due to a fault in the components that make up the reactor.

In the case of the conventional safety system of nuclear power plants, it was possible to respond promptly to general SPVs. However, it can respond effectively to reactor shutdown inducing factors caused by a single failure including three types of Universal Logic Card, Safeguard Driver and Under- Voltage Coil Driver. There was a problem that could not be done. In particular, since 70 to 80 to 90 SPVs can be present among three types of SPVs, the conventional safety system of a nuclear power plant is very vulnerable to the protection design against generation of the three kinds of SPVs.

Referring to FIG. 1, failure of the safety system of a nuclear power plant must consider CCF (Common Caused Failure) as well as SPV. CCF is a potential fault common to all equipment. If CCF occurs, all sensors or all reactor safety systems fail or fail to operate properly. For example, in the case of the Y2K problem, when all of the equipment reaches the year 2000, it can cause rapid chaos and death of computing devices.

Conventional safety systems for nuclear power plants are protected against SPV, but CCF is not taken into consideration. Therefore, when the CCF occurs, the entire nuclear power plant can not operate properly. If a situation occurs in which the reactor must stop its operation due to excessive operation at the same time as the CCF occurs, the control rod falling down to stop the operation of the reactor can not be properly operated, and a large accident may necessarily occur.

As described above, in order to solve the problem of being vulnerable to a single failure type (SPV) and a common failure type (CCF) of a conventional safety system of a nuclear power plant, Channel and a train of the nuclear power plant.

The technical problem to be solved by the present invention is not limited to the above-mentioned technical problems, and various technical problems can be included within the scope of what is well known to a person skilled in the art from the following description.

According to an aspect of the present invention, there is provided a safety system for a nuclear power plant, the system including a first process protection controller and a second process protection controller which are independent from each other, At least two or more channels, mutually independent first and second abnormality controllers, and a second abnormality controller, and generating and transmitting to the switching module a switching control signal according to the reactor abnormality signal Two or more trains, and a switching module that, in response to the switching control signal, stop the reactor when the reactor is normal and the reactor is operating normally and the reactor is abnormal.

Also, the safety system of a nuclear power plant according to an embodiment of the present invention is characterized in that the channel includes a first channel, a second channel, a third channel, and a fourth channel.

In addition, the safety system of a nuclear power plant according to an embodiment of the present invention is characterized in that the train includes a first train and a second train.

In addition, the safety system of a nuclear power plant according to an embodiment of the present invention is characterized in that the channel includes an FPGA-based first process protection controller and a PLC-based second process protection controller.

In addition, in the safety system of a nuclear power plant according to an embodiment of the present invention, the process protection controller transmits the reactor abnormality signal to all abnormality judgment controllers of the same type.

In the safety system of a nuclear power plant according to an embodiment of the present invention, a reactor abnormality signal is generated based on the reactor state information collected by the process protection controller and is transmitted to an abnormality determination controller.

At this time, in the safety system system of a nuclear power plant according to an embodiment of the present invention, the reactor state information includes reactor coolant high temperature pipe temperature information, reactor coolant low temperature pipe temperature information, pressurizer pressure information, neutron flux information, And at least one of them is included.

In addition, the safety system of a nuclear power plant according to an embodiment of the present invention determines whether or not the reactor is abnormal according to the number of normal signals and abnormal signals included in the signal of abnormality of the reactor received by the abnormality determination controller, To the switching module.

At this time, in the safety system of a nuclear power plant according to an embodiment of the present invention, when the abnormality determination controller includes two or more abnormality signals, the abnormality determination controller determines that the abnormality is abnormal.

In the safety system of a nuclear power plant according to an embodiment of the present invention, even if a single failure element (SPV) or a common failure element (CCF) occurs in the process protection controller or the abnormality determination controller, It is possible to stop the reactor.

In addition, in the safety system of a nuclear power plant according to an embodiment of the present invention, the switching module includes a power source, a control rod control unit, a first NO contact point connected between the power source and a central node, 1 NC contact, a second NC contact connected between the central node and the control rod control unit, and a second NO contact connected between the center node and the control rod control unit.

In the safety system of a nuclear power plant according to an embodiment of the present invention, at least one of the first NO contact or the first NC contact is in a closed state, and at least one of the second NC contact or the second NO contact And the power is supplied to the control rod control unit when any one of the first and second control units is in a closed state.

In the safety system of a nuclear power plant according to an embodiment of the present invention, when the power is not applied, the control rod control unit drops the control rod to stop the reactor, and when the power is applied, It is characterized by normal operation of the reactor.

In the safety system of a nuclear power plant according to an embodiment of the present invention, the switching control signal includes a serial circuit control signal and a parallel circuit control signal, and the first abnormality determination controller or the second abnormality determination controller, And generates the serial circuit control signal and the parallel circuit control signal.

In this case, the safety system of the nuclear power plant according to an embodiment of the present invention may further include a first series circuit for controlling the closing / opening of the first NO contact according to the switching control signal, A first parallel circuit for controlling the closing / opening of the first NC contact, a second parallel circuit for controlling the closing / opening of the second NC contact in accordance with the switching control signal, And a second series circuit for controlling the closing / opening of the NO contact.

In the safety system of a nuclear power plant according to an embodiment of the present invention, the first series circuit, the first parallel circuit, the second parallel circuit, and the second series circuit are connected to each other by an anomaly judgment controller And receives a switching control signal from the switching control unit.

The safety system of a nuclear power plant according to an embodiment of the present invention includes two switches connected in series to the first series circuit or the second series circuit, Closes the first NO contact or the second NO contact when the switch is turned on and at least one of the switches is turned off when the first NO contact or the second NO contact is turned off, And the NO contact is opened.

According to another aspect of the present invention, there is provided a safety system of a nuclear power plant including two switches connected in parallel to the first parallel circuit or the second parallel circuit, wherein the switch is turned on / Closing the first NC contact or the second NC contact when the switches are all turned off and when at least one of the switches is on, the first NC contact or the second contact And the NC contact is opened.

The safety system of a nuclear power plant according to the present invention eliminates a reactor shutdown inducing element (SPV) caused by a single failure of an existing facility and prevents a nuclear power plant from stopping even in the event of a single failure. By applying diversity to the safety system itself, Even when the fault occurs (CCF), safe operation is possible without losing the function of the protection system.

In addition, the safety system of the nuclear power plant of the present invention considers the diversity and independence of the protection system as a consideration of the common type failure. By including different kinds of process protection controllers and anomaly judgment controllers, All can be effectively prepared.

In addition, the safety system of a nuclear power plant of the present invention can perform a reactor protection function even in the case of a common type failure, thereby enhancing safety and reliability.

In addition, the safety system of a nuclear power plant of the present invention can operate a power plant and improve maintainability in a zero (Zero) situation.

Figure 1 relates to Common Caused Failure (CCF) that can occur in prior art reactor protection system structures.
FIG. 2 is a comparative view of a conventional safety system of a nuclear power plant according to the embodiment of the safety system of a nuclear power plant of the present invention.
3 is a block diagram of a safety system of a nuclear power plant according to the present invention.
FIG. 4 is a diagram showing the configuration of a channel and a train included in the safety system of a nuclear power plant according to the present invention.
FIG. 5 is a representative view of the present invention, and relates to a detailed embodiment of a switching module of a safety system system of a nuclear power plant.
FIGS. 6A, 6B, 7A, 7B, 8A, and 8B relate to various embodiments in which the nuclear safety system of the present invention controls reactor normal operation or reactor shutdown according to various failure types.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a 'safety system for a nuclear power plant' according to the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the above-described embodiments, and various changes and modifications may be made without departing from the scope of the present invention. In addition, the matters described in the attached drawings may be different from those actually implemented by the schematic drawings to easily describe the embodiments of the present invention.

In the meantime, each constituent unit described below is only an example for implementing the present invention. Thus, in other implementations of the present invention, other components may be used without departing from the spirit and scope of the present invention.

Also, the expression " comprising " is intended to merely denote that such elements are present as an expression of " open ", and should not be understood to exclude additional elements.

Also, the expressions such as 'first, second', etc. are used only to distinguish between plural configurations, and do not limit the order or other features among the configurations.

In the description of the embodiments, it is to be understood that each layer (film), area, pattern or structure may be referred to as being "on" or "under / under" Quot; includes all that is formed directly or through another layer. The criteria for top / bottom or bottom / bottom of each layer are described with reference to the drawings.

 When a part is "connected" to another part, it includes not only "directly connected" but also "indirectly connected" with another part in between. Also, when an element is referred to as "comprising ", it means that it can include other elements, not excluding other elements unless specifically stated otherwise.

FIG. 2 is a comparative view of a conventional safety system of a nuclear power plant according to the embodiment of the safety system of a nuclear power plant of the present invention.

Referring to FIG. 2, in the conventional safety system of a nuclear power plant, the multiplexed channel is hard-wired with various cabinets, circuits, and lines, so that the size and volume occupied by the safety system system of the power plant becomes very large .

However, in the case of the safety system of the nuclear power plant according to the present invention, a plurality of channels can be implemented in the form of a chip, and signals used in a safety system such as a reactor abnormality signal, a switching control signal, So that all operations can be performed in a small controller.

In order to prevent the occurrence of CCF, the safety system of the nuclear power plant of the present invention duplicates the controllers into different types and implements the conventional analog safety system as a digital safety system to facilitate the maintenance of the nuclear power plant .

FIG. 3 is a block diagram of a safety system of a nuclear power plant according to the present invention, and FIG. 4 is a block diagram of a channel and a train of a nuclear power plant safety system of the present invention.

3 and 4, the safety system of a nuclear power plant of the present invention may include channels 221, 222, 223, and 224, trains 231 and 232, and a switching module 240.

The channels 221, 222, 223 and 224 include different types of first process protection controllers 221-1 and 222-1 and second process protection controllers 221-2 and 222-2, And transmit a signal to the trains 231 and 232, respectively. In this case, the channel may include a first channel, a second channel, a third channel, and a fourth channel, and may be implemented by two, three, or four channels.

More specifically, the channel may generate a reactor anomaly signal based on the reactor state information collected by the sensing device installed in the reactor, and transmit the signal to the anomaly determination controller or the train including the anomaly determination controller. The process protection controller can receive the same on-site sensor signals and perform the anomaly detection algorithms independently of each other.

For example, the channel detects temperature information, which is state information detected by a reactor, and determines whether or not there is an abnormality (1) or not (0) To the controller. In the safety system of a nuclear power plant according to the present invention, since a sensing device is multiplexed, an abnormality may occur in one or more of the plurality of sensing devices.

At this time, the reactor state information includes at least one of reactor coolant high temperature pipe temperature information, reactor coolant low temperature pipe temperature information, pressurizer pressure information, neutron flux information, and reactor coolant flow rate information.

At this time, each channel is physically / electrically separated, and each channel can independently derive its result signal. If two or more channels are judged to be abnormal, it is finally decided as an abnormal condition of the nuclear power generation apparatus .

For example, when the channel is composed of 3 or 4 channels, if the 2/3 or 2/4 channel judges an abnormal signal, it can be decided as an abnormal situation. In addition, the number of channels determined to be abnormal can be changed according to the total number of channels such as one, three, four, etc. as well as two. For example, if the total number of channels is increased or decreased such as 1/2, 1/3, 3/5, 3/4, 4/6, 4/7, etc., the number of channels to be determined as abnormal situations may be adjusted.

In addition, the channel of the present invention may include a process protection controller. Each channel may include a first process protection controller and a second process protection controller. At this time, the process protection controller included in the channel may be referred to as a comparative logic controller (bistable processor), and may perform the function of the comparison logic control.

Also, the first process protection controller and the second process protection controller may be configured as mutually independent different types. For example, the first process protection controller can be configured on an FPGA basis, the second process protection controller can be configured on a PLC basis, and the two process protection controllers can be controlled independently of each other. This makes it possible to effectively operate both the SPV and the CCF because the reactor safety protection system can be operated only by the devices constituted by the rest of the PLC even if the CCF occurs in the device constituted by the FPGA.

At this time, the process protection controller can transmit the reactor abnormality signal to all the abnormality judgment controllers of the same kind, respectively. Since the two process protection controllers configured in the channel are of different types, the control is independent of the same kind of device, from the reactor-channel (process protection controller) to the train (fault decision controller) -to the switching module- . For example, an FPGA-based device operates independently of a PLC-based device without being influenced by each other, so that a safety protection system can be operated even when a CCF occurs.

The trains 231 and 232 may include first and second abnormality controllers of different types and may generate a switching control signal according to the reactor abnormality signal and transmit the switching control signal to the switching module.

At this time, the train may include a first train 231 and a second train 232. The first train 231 may include a first abnormal decision controller 231-1 and a second abnormal decision controller 231-2 and the second train 232 may include a first abnormal decision controller 232-1 And a second abnormality determination controller 232-2.

At this time, the abnormality determination controller may be referred to as a reactor protection system controller or a co-incidence processor, and may perform a function of simultaneous logic control.

The abnormality judgment controller included in the train and the train receives the abnormality signal of the reactor received by the channel. At this time, a signal indicating whether or not the reactor abnormality is received from all multiplexed channels is received.

More specifically, the abnormality determination controller determines whether or not the reactor abnormality is abnormal according to the number of normal signals and abnormality signals included in the received abnormality signal of the reactor, and transmits a switching control signal according to the reactor abnormality to the switching module .

For example, the number of channels is three or four, and the abnormality determination controller can determine that the reactor abnormality is abnormal when the abnormality determination signal includes two or more abnormality signals. Therefore, if two or more channels among four channels detect abnormality in the reactor, the safety system of the nuclear power plant will take measures such as dropping the control rod after judging it as abnormal condition of the reactor.

According to the switching control signal transmitted from the abnormality judging controller included in the train or train, the switching module 240 can stop the reactor when the reactor is normal and the reactor is in normal operation and the reactor is abnormal.

At this time, the switching module of the present invention can be implemented as a reactor stop switchgear system (RTSS) in a safety system of a nuclear power plant.

At this time, the switching module can stop the reactor in the event of a reactor failure even if a single failure element (SPV) or a common failure element (CCF) occurs in the process protection controller or the abnormality determination controller. At this time, the reactor abnormality may include various situations in which a reactor shutdown is required, internal / external damage occurs in the reactor, or when the reactor design is abnormal.

Since the two trains controlling the switching module are composed of different kinds of anomaly judgment controllers, even if one of the anomaly judgment controllers generates the CCF, the other one of the abnormality judgment controllers sets the control signal path .

5 is a detailed block diagram of a switching module of a safety system of a nuclear power plant according to the present invention. In this case, FIG. 5 shows only the devices of the same kind or group by channel, so that the path of the control signal can be clearly identified.

The switching module 240 includes a power source 241, a control rod control portion 242, a first NO contact 243, a first NC contact 244, a second NC contact 245 and a second NO contact 246 can do.

The power supply 241 supplies the driving power for operating the control rod control unit. At this time, the power source 241 of the present invention may use commercial power or supply the driving power to the motor-generator set (MG-set).

In the switching module of the present invention, the NO contact point and the NC contact point are located between the power source and the control rod control section, so that the power source may supply the driving power control section to the control rod control section or not have.

More specifically, when at least one of the first NO contact or the first NC contact is in a closed state and at least one of the second NC contact or the second NO contact is in a closed state, And a power source is applied. This is because the first NO contact and the first NC contact are connected in parallel to each other and the second NC contact and the second NO contact are connected in parallel to each other, And can be supplied to the control rod control unit.

The control rod control unit 242 adjusts the control rod to control the reactor nuclear reaction degree so as to control the normal operation of the reactor or the shutdown of the reactor. At this time, the control rod control unit can control the stoppage and operation of the reactor by generating or stopping the control rod drop signal. Further, the control rod control unit is implemented as the control rod driving unit and directly grips the control rod. Release the control rod by gravity.

More specifically, the control rod control unit stops the reactor by dropping the control rod when the power source is not applied, and maintains the control rod position when the power source is applied, thereby operating the reactor normally. As the control rod drops and the reactor stops immediately, it becomes possible to take quick action in case of abnormal reactor conditions.

The switching module of the present invention is composed of an NO contact (or a contact) and an NC contact (or a contact b), so that the safety system can be stably operated even when a common fault element occurs in conjunction with the series circuit and the parallel circuit.

In the case of the NO contact (or the contact a), the fixed contact and the movable contact are separated from each other in the initial state, and when the force is applied from the outside, the fixed contact and the movable contact come into contact with each other. In other words, in the normally open state, when the force (ex: electromagnetic force) occurs from the outside, the contact state is changed to the closed state. In the case of Fig. 5, the NO contact point can be changed from an open state to a closed state by an electromagnetic force generated in the coil when a current flows in the series circuit.

In the case of the NC contact (or b contact), the fixed contact and the movable contact are attached in the initial state, and when the external force is applied, the contact is broken down and the current can not flow. In other words, when a force (ex: electromagnetic force) occurs from the outside in the state of being normally closed (normally closed), the state is changed to an open state by disassociating the contact. In the case of Fig. 5, when an electric current flows in the parallel circuit, the NC contact can change from the closed state to the open state due to the electromagnetic force generated in the coil.

The first NO contact 243 is connected between the power supply 241 and the central node 247.

The first NC contact 244 is connected between the power supply 241 and the central node 247.

A second NC contact 245 is connected between the central node 247 and the control rod control 242.

A second NO contact 246 is connected between the central node 247 and the control rod control 242.

In addition, the switching module 240 of the present invention may include a first serial circuit 251, a first parallel circuit 252, a second parallel circuit 253, and a second serial circuit 254. The series circuit or the parallel circuit may control the power source to be applied to the control rod control unit by causing the NO contact or the NC contact to close / open. To this end, the switching control signal includes a serial circuit control signal and a parallel circuit control signal, and the first abnormal decision controller or the second abnormal decision controller generates the serial circuit control signal and the parallel circuit control signal .

In this case, the switch included in the series circuit or the parallel circuit of the present invention may be implemented as a separate circuit such that the series circuit and the parallel circuit are closed / opened as shown in FIG. 5, Or may be hard-wired and connected to a coil that closes / opens the contact.

For example, the switching control signal controls the ON / OFF state of the series circuit through switch control, and the NO contact connected to the series circuit repeats contact / contact release according to the ON / OFF of the series circuit.

The first series circuit 251 can control the closing / opening of the first NO contact 243 in accordance with the switching control signal.

The first parallel circuit 252 can control the closing / opening of the first NC contact 244 in accordance with the switching control signal.

The second parallel circuit 253 can control the closing / opening of the second NC contact 245 in accordance with the switching control signal.

The second series circuit 254 can control the closing / opening of the second NO contact 246 in accordance with the switching control signal.

In this case, the first serial circuit, the first parallel circuit, the second parallel circuit, and the second serial circuit receive switching control signals from different types of error determination controllers. The series circuit or the parallel circuit constituting the switching module of the present invention receives the switching control signal from the different kind of abnormality judging controller so that the safety of the reactor can be maintained even if any abnormality judging controller stops operating.

More specifically, the first serial circuit or the second serial circuit includes two switches connected in series, the switch being turned on / off by the switching control signal, and when the switches are all on, The first NO contact or the second NO contact is turned off when at least one of the switches is turned off and the first NO contact or the second NO contact is turned off.

The switches configured in the serial circuit receive switching control signals from different error judging controllers. For example, when receiving a switching control signal (switch-on) from an FPGA-based abnormality judgment controller and a switching control signal (switch-on) from a PLC-based abnormality judgment controller, the first serial circuit outputs both switches And accordingly, the first NO contact is closed.

On the contrary, when the switching control signal of at least one of the FPGA-based abnormality judgment controller or the PLC-based abnormality judgment controller is switched off, the series circuit is in the off state and the first NO contact is in the open state do.

More specifically, the first parallel circuit or the second parallel circuit includes two switches connected in parallel, the switch being turned on / off by the switching control signal, and when all the switches are off, Closing the first NC contact or the second NC contact and opening the first NC contact or the second NC contact when at least one of the switches is on.

The switches constituted in the parallel circuit receive switching control signals from different error judgment controllers. For example, when receiving a switching control signal (switch-off) from an FPGA-based abnormality judgment controller and a switching control signal (switch-off) from a PLC-based abnormality judgment controller, the first parallel circuit turns off both switches So that the first NC contact is opened.

In contrast, when the switching control signal of at least one of the FPGA-based abnormality-judgment controller or the PLC-based abnormality-judgment controller is switched on, the parallel circuit is in the closed state and the first NC contact is in the open state .

Accordingly, in the safety system of the nuclear power plant of the present invention, power is supplied in the order of the power source-contact-control rod control unit, and when no power is supplied according to the close / open state of the contact, the control rod control unit generates a control rod drop signal Let the reactor shut down.

FIGS. 6A, 6B, 7A, 7B, 8A, and 8B relate to various embodiments in which the nuclear safety system of the present invention controls reactor normal operation or reactor shutdown according to various failure types.

6A relates to the operation of the switching module of the present invention in the normal situation of the power plant / safety system. When the nuclear power plant is normal and the safety system is normal, all the contacts included in the switching module of the present invention remain closed and the power is applied to the control rod control unit. Therefore, the control rod control unit does not drop the control rod, and the reactor operates normally.

Figure 6b relates to the operation of the switching module of the present invention in the steady state of the abnormal situation / safety system of the power plant. When the nuclear power plant is abnormal and the safety system is normal, all the contacts included in the switching module of the present invention remain open, and the power is not applied to the control rod control unit. Therefore, the control rod control unit drops the control rod, and the operation of the reactor is stopped by the control rod falling.

FIG. 7A relates to the operation of the switching module of the present invention in the steady state / safety system of the power plant. Nuclear power plant is normal, but PLC-based abnormality control of safety system signal (switch-on) may appear unless PA-2 signal and PB-2 signal are original signal (switch off).

At this time, in the parallel circuit, either of the two switches is turned on, so that the NC contact is changed from the closed state to the off state. However, since the NO contacts controlled by the series circuit still remain closed, the power can be normally applied to the control rod control unit via the power source-first NO contact-second NO contact-control rod control unit, .

7B relates to the operation of the switching module of the present invention in an abnormal situation / safety system of the power plant. It is the worst case where the nuclear power plant is abnormal and the safety system is also abnormal. In this case, since the nuclear power plant is abnormal, the safety system must immediately drop the control rod to stop the reactor, but the safety system may not be able to fall properly due to a problem in the safety system.

However, the safety system of the present invention can solve this problem. For example, if the PLC-based anomaly detection controller of the safety system is not the original signal (switch off) of the PA-1 signal and the PB-1 signal, the signal (switch on) may appear. At this time, in the series circuit, one of the two switches is in the OFF state, so that the NO contact remains open. Therefore, since the NO and NC contacts are all kept open, power is not supplied to the control rod control unit, and the control rod falls and the reactor operation is stopped.

Fig. 8A relates to the operation of the switching module of the present invention in the steady-state situation / safety system of the power plant. Unlike FIG. 7A, the PLC-based anomaly determination controller of the safety system may generate a signal (switch-off) when the PA-1 signal and the PB-1 signal are not the original signal (switch on).

At this time, in the series circuit, one of the two switches is in the OFF state, so that the NO contact remains open. However, since the NC contacts controlled by the parallel circuit are still closed, the power can be normally supplied through the power source - first NC contact - second NC contact - control rod control part.

FIG. 8B relates to the operation of the switching module of the present invention in the abnormal state of the power plant / abnormal state of the safety system. It is the worst case where the nuclear power plant is abnormal and the safety system is also abnormal. In this case, since the nuclear power plant is abnormal, the safety system should immediately drop the control rod, but there is a problem with the safety system and the control rod may not fall properly.

However, the safety system of the present invention can solve this problem. For example, if the PLC-based anomaly detection controller of the safety system is not the original signal (switch-on), the signal (switch-off) may appear on the PA-2 and PB-2 signals. At this time, in the parallel circuit, either of the two switches is turned on, so that the NC contact is changed from the closed state to the open state. Therefore, NO and NC contact points are all kept open, so no power is supplied to the control rod control unit, and the control rod falls and the reactor is stopped.

6A and 8B, in the safety system of a nuclear power plant according to the present invention, even if any one of the safety systems fails in an emergency where a control rod falling signal must necessarily occur, the remaining switches and contacts are complementary It is possible to normally operate the safety system of the nuclear power plant and to deal with the reactor normal operation or the reactor shutdown even if the SPV or CCF situation occurs.

The embodiments of the present invention described above are disclosed for the purpose of illustration, and the present invention is not limited thereto. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention.

210: reactor
221: First channel
221-1, 222-1: first process protection controller
221-2, 222-2: second process protection controller
222: Second channel
223: the third channel
224: the fourth channel
231: 1st train
231-1, 232-1: a first abnormality determination controller
231-2, 232-2: a second abnormality determination controller
232: Second train
240: switching module
241: Power supply
242:
243: First NO contact
244: 1st NC contact
245: 2nd NC contact
246: Second NO contact
247: Central node
251: First serial circuit
252: first parallel circuit
253: Second parallel circuit
254: second serial circuit
251-1, 251-2, 252-1, 252-2: switches

Claims (18)

At least two or more channels including mutually independent different kinds of first process protection controllers and second process protection controllers and transmitting signals of reactor abnormality signals to the train;
At least two or more trains each including a first abnormality determination controller and a second abnormality determination controller of different types and generating a switching control signal according to the reactor abnormality signal and transmitting the switching control signal to the switching module;
A switching module for normally operating the reactor in the case where the reactor is normal and stopping the reactor in the event that the reactor is abnormal according to the switching control signal;
≪ / RTI >
The switching module includes:
power;
A control rod control unit;
A first NO contact connected between the power supply and a central node;
A first NC contact coupled between the power supply and a central node;
A second NC contact connected between the central node and the control rod control unit;
A second NO contact connected between the central node and the control rod control unit;
And the safety system of the nuclear power plant.
The method according to claim 1,
The channel may comprise:
Wherein the system includes a first channel, a second channel, a third channel, and a fourth channel.
The method according to claim 1,
The train includes:
A first train, and a second train.
The method according to claim 1,
The channel may comprise:
An FPGA-based first process protection controller;
PLC based second process protection controller;
And the safety system of the nuclear power plant.
The method according to claim 1,
Wherein the process protection controller comprises:
Wherein the abnormality determination signal is transmitted to all abnormality judgment controllers of the same type.
The method according to claim 1,
Wherein the process protection controller comprises:
And generates an abnormality signal of the reactor based on the collected reactor state information and transmits the signal to the abnormality determination controller.
The method according to claim 6,
The reactor state information includes:
A reactor coolant high temperature pipe temperature information, a reactor coolant low temperature pipe temperature information, a pressurizer pressure information, a neutron flux information, and a reactor coolant flow rate information.
The method according to claim 1,
The abnormality determination controller includes:
Wherein the control unit determines whether or not the reactor is abnormal according to the number of the normal signal and the abnormal signal included in the received signal of the abnormality of the reactor and sends a switching control signal according to the abnormality of the reactor to the switching module.
9. The method of claim 8,
Wherein the abnormality determination controller determines that the reactor abnormality is abnormal if the abnormality of the reactor abnormality signal includes two or more abnormality signals.
The method according to claim 1,
The switching module includes:
Wherein the reactor can be shut down if there is an abnormality in the reactor even if a single failure element (SPV) or a common failure element (CCF) occurs in the process protection controller or the abnormality determination controller.


delete The method according to claim 1,
Wherein at least one of the first NO contact or the first NC contact is in a closed state,
When at least one of the second NC contact or the second NO contact is in a closed state,
And the power is applied to the control rod control unit.
The method according to claim 1,
The control-
When the power source is not applied, the control rod is dropped to stop the reactor,
Wherein when the power source is applied, the control rod position is maintained and the reactor is operated normally.
The method according to claim 1,
Wherein the switching control signal includes a serial circuit control signal and a parallel circuit control signal,
Wherein the first abnormal decision controller or the second abnormal decision controller comprises:
And the serial circuit control signal and the parallel circuit control signal are generated.
The method according to claim 1,
The switching module includes:
A first serial circuit for controlling the closing / opening of the first NO contact according to the switching control signal;
A first parallel circuit for controlling the closing / opening of the first NC contact in accordance with the switching control signal;
A second parallel circuit controlling the closing / opening of the second NC contact in accordance with the switching control signal;
A second series circuit for controlling the closing / opening of the second NO contact according to the switching control signal;
And the safety system of the nuclear power plant.
16. The method of claim 15,
Wherein the first serial circuit, the first parallel circuit, the second parallel circuit,
And a switching control signal is received from all of the different kinds of abnormality judgment controllers.
16. The method of claim 15,
Wherein the first serial circuit or the second serial circuit comprises:
And two switches connected in series, wherein the switch is turned on / off by the switching control signal,
Closing the first NO contact or the second NO contact when the switch is all ON,
And opens the first NO contact point or the second NO contact point when at least one of the switches is off.
16. The method of claim 15,
Wherein the first parallel circuit or the second parallel circuit comprises:
And two switches connected in parallel, wherein the switch is turned on / off by the switching control signal,
Closing the first NC contact or the second NC contact when all of the switches are off,
Wherein the first NC contact or the second NC contact is opened when at least one of the switches is ON.

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