KR101026159B1 - A system for assessing the effect of human related events in nuclear power plants and the method thereof - Google Patents

Abstract

The present invention relates to a system and method for evaluating the impact of human incidence events in nuclear power plants. More specifically, the human incidence incidents caused by human error during daily work in relation to the daily work performed in the nuclear power plant are related to the safety and The present invention relates to an evaluation system and method for quantitatively analyzing the degree of impact on performance to effectively evaluate and manage the uninterrupted stoppage and deterioration of a nuclear power plant caused by human factors.

Human impact event evaluation system of a nuclear power plant according to the present invention, by receiving the job information including the job characteristics and job performance environment for the daily duties performed in the nuclear power plant from the user, by using the input job information A human error analysis module for calculating a probability of human error for each job, and acquiring malfunction information corresponding to each of the input jobs by referring to predetermined function failure data for each job; Receive each job information input by the user from the human error analysis module and the human error probability and malfunction information for each job, and apply the functional information corresponding to each job to the deterministic model A safety evaluation module for analyzing the effects of malfunctions caused by human error on each job on the safety of nuclear power plants; Receive each job information input by the user from the human error analysis module and the malfunction information for each job, the human resources of each job in terms of thermal efficiency in the nuclear power plant system based on the corresponding malfunction information for each job And a performance simulation module for simulating the effect of a malfunction caused by a failure on the performance degradation of the nuclear power plant.

Nuclear Power Plant, Daily Occupation, Human Accident, Human Error, Uninterrupted Stop, Performance Degradation, Impact Assessment

Description

System for assessing the effect of human related events in nuclear power plants and the method

The present invention relates to a system and method for evaluating the impact of human incidence events in nuclear power plants. More specifically, the human incidence incidents caused by human error during daily work in relation to the daily work performed in the nuclear power plant are related to the safety and The present invention relates to an evaluation system and method for quantitatively analyzing the degree of impact on performance to effectively evaluate and manage the uninterrupted stoppage and deterioration of a nuclear power plant caused by human factors.

Many experiences and accidents in nuclear power plants have been known so far that one of the decisive causes of events or accidents occurring in nuclear power plants is human factors. For example, about 40% of the uninterrupted events in 2004 and 2005 were found to be related to human factors, and more than 80% of the uninterrupted incidents related to human factors are inadequate daily work at nuclear power plants. (Maintenance / testing jobs and abnormal response jobs).

Recently, nuclear power plants continue to increase unit capacity, add and diversify measurement control systems, introduce advanced electronic and artificial intelligence technologies, and reinforce safety facilities to enhance safety. As a result, nuclear power plants become more complex, and the role of humans in operating them is increasing. Despite the facilitation of automation, current operators of nuclear power plants must closely monitor the operation of the system, diagnose faults, and be aware of the failure / stopping procedures for safe operation. In addition, there is a heavy burden of work, such as understanding the operation information of the nuclear power plant that is runaway in abnormal and emergency situations and responding quickly and accurately.

Nuclear power plants are defined by system designers and are designed by assigning the defined functions between humans and machines. Humans sense, interpret, and make decisions based on the information provided by systems designed by designers. The performance of these workers is influenced by internal and external human factors on the workers, and it is impossible to fully reflect these human factors in the design, so it is impossible to reflect them in the design. There is a difference between the performance of workers in actual nuclear power plant operations.

Therefore, in order to reduce the number of uninterrupted stops of nuclear power plants and ultimately increase the safety of nuclear power plants, it is required to improve the human behavior and errors of operators or workers who are the main operators of nuclear power plants.

To this end, there is a need for a system that can suggest effective human error reduction through the evaluation of human related events that may occur during daily work related to uninterrupted or reduced functioning.

The present invention solves the problems of the prior art described above. That is, an object of the present invention is to quantitatively analyze the degree to which human incidence events caused by human error during daily duties in the nuclear power plant affect the safety and performance of the system. The present invention provides an evaluation system and method for effectively evaluating and managing an uninterrupted stoppage and a degradation of a nuclear power plant.

The present invention as a technical idea for achieving the above object, by receiving the job information including the job characteristics and the job performance environment for the daily jobs performed in the nuclear power plant from the user, each using the input job information A human error analysis module for calculating a probability of human error for a job, and acquiring malfunction information corresponding to each of the input jobs by referring to predetermined function failure data for each job; Receive each job information input by the user from the human error analysis module and the human error probability and malfunction information for each job, and apply the functional information corresponding to each job to the deterministic model A safety evaluation module for analyzing the effects of malfunctions caused by human error on each job on the safety of nuclear power plants; Receive each job information input by the user from the human error analysis module and the malfunction information for each job, and based on the malfunction information corresponding to each job, each job in terms of thermal efficiency in the nuclear power plant system A performance simulation module for simulating the effect of malfunction due to human error on the deterioration of a nuclear power plant.

In another aspect, the present invention, by providing an input screen for inputting the job information to the user, receiving the job information for the daily duties performed in the nuclear power plant from the user through the input device, and each of the received job Calculating human error probability (HEP) related to performing the corresponding job in the central processing unit by using the information, and performing each of the inputted tasks with reference to predefined job loss data. Acquiring information on malfunctions that may be caused by human error, and referring to the acquired malfunction information for each job, for each job, a function classified into a safety-related malfunction and a performance-related malfunction Determining the type of loss, and if the determined type of malfunction is a safety-related malfunction, Evaluating the effect of functional failure on the safety of the nuclear power plant by applying the functional information to the deterministic model, and if the determined type of functional failure is a performance-related malfunction, Simulating the effect of functional failure due to human error of the job on performance degradation related to thermal efficiency of nuclear power plant system, evaluating the impact on safety and performance degradation When the safety evaluation and performance degradation simulation of the entire job inputted from the user are completed through the step of simulating the impact, the output device displays a list of all jobs and the safety evaluation and performance degradation simulation results for each job to the user. Characterized in that comprises a Provides a method for assessing the impact of human outbreaks in nuclear power plants.

The system and method for evaluating the impact of human incidence events on nuclear power plants according to the present invention can analyze quantitatively the effects of human error related to each daily work on nuclear power plants on the safety and performance of the system. As a result, measures to reduce human error related to important daily tasks can be easily derived, thereby reducing the number of uninterrupted stops of nuclear power plants, and improving the safety and economic efficiency of nuclear power plants by reducing the performance degradation of major systems. It can be effective.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of a system for evaluating human impact events according to an embodiment of the present invention.

The human incidence event impact evaluation system of a nuclear power plant according to the present invention is implemented through a computer system including an input device, a central processing unit, and an output device, the human induction according to one embodiment of the present invention shown in FIG. The event impact assessment system is largely composed of human error analysis module 10, safety evaluation module 20, performance simulation module 30, importance analysis and output module 40.

The human error analysis module 10 receives from the user information on daily jobs performed at the nuclear power plant, that is, job information including job characteristics and job performance environment through an input device, and uses the input job information. Calculates the probability of human error for a job, and uses the user's function using predefined job loss data, i.e., data that predefine the type of malfunction of the nuclear power plant equipment due to human error during each job for all jobs. Acquire the malfunction information corresponding to each job input from.

The safety evaluation module 20 receives the job information input by the user from the human error analysis module 10 and the human error probability and malfunction information for each job to determine the corresponding malfunction information for each job. Applying to the deterministic model, we analyze the effects of human error of each job on the safety of nuclear power plants. Here, the deterministic model is preferably established using a fault tree mainly used in the probabilistic safety assessment (PSA) of nuclear power plants, which will be described in detail later. do.

The performance simulation module 30 receives the job information input by the user and the function failure information for each job from the human error analysis module 10, and based on the function loss information corresponding to each job, the nuclear power plant system In this paper, the effect of human error of a specific job on the deterioration of nuclear power plant is simulated and analyzed.

The importance analysis and output module 40 receives safety impact and performance impact analysis results for each job from the safety evaluation module 20 and the performance simulation module 30, and uses the safety impact and performance impact analysis results delivered. It calculates the importance of how important each job affects the safety and performance of the nuclear power plant, and displays the analysis result including the calculated job importance to the user through the output device.

Hereinafter, a method for evaluating the impact of a human incident event according to an embodiment of the present invention using the evaluation system configured as described above will be described.

FIG. 2 is a flowchart illustrating a process of evaluating a human incident event according to an embodiment of the present invention, FIG. 3 is a view showing an example of an input screen in the job information input step shown in FIG. 2, and FIG. 4 is shown in FIG. 2. A diagram showing the concept of fault trees used in the illustrated safety impact analysis step.

Referring to FIG. 2, first, the human error analysis module 10 provides an input screen for inputting job information to a user, and performs a job routinely performed in a nuclear power plant such as a maintenance or test job from a user through an input device. They receive information on their job characteristics and job performance environment (S10), and calculate human error probability (HEP) related to the job performance using each job information input from the user (S20). .

Here, the human error probability is preferably calculated by applying the Korean Human Reliability Analysis (K-HRA) technique developed by the Korea Atomic Energy Research Institute, the applicant of the present invention, the job characteristics input from the user when applying the K-HRA technique And it is possible to effectively calculate the probability of human error according to the information on the job performance environment.

As the job information to be input in the S10 in order to apply the K-HRA technique, as shown in Figure 3, job name (I1), job type information (I2), stress level information (I3), etc. There is this. In job name (I1), standardized job names for jobs routinely performed at the nuclear power plant, such as maintenance or test jobs, are entered, based on procedures commonly used in nuclear power plants, and job type information (I2). The furnace will enter the complexity of the job, the level of difficulty of the procedure, and the worker's familiarity with the job. On the other hand, the stress level information (I3) includes time urgency of how quickly the task should be completed, the severity of the situation in which the task should be performed (e.g., a post-accident task in response to a fatal accident). The level of severity), the risks involved in performing the job, and the level of education and training for how well the worker is performing. In addition, when failure to perform a job due to human error, error recovery information (I4) for the error, that is, time urgency required for recovery, man-machine interface (MMI) provision level related to recovery, Receive information on whether or not a supervisor can be input. In addition, although not illustrated in the drawing, in addition to the information related to the above job characteristics, information related to the job environment, that is, environmental information such as the margin of work space or the noise level of the work space may be input. . Each job information entered as described above is stored in a data repository such as a database. When the worker of a specific job is replaced or the skill level is increased, the information is updated by retrieving the previously stored job information and inputting the changed item. It is possible.

As such, when job information such as job type information, stress level information, and error recovery information is input through step S10, in step S20, the human error analysis module 10 is driven to use the input job type information and stress information. By calculating the job error probability of the corresponding job, and calculating the recovery failure probability from the error recovery information, the final human from the product of the operation error probability (Pr ₁ ) and recovery failure probability (Pr ₂ ) as shown in Equation 1 below Error probability Pr ₃ is calculated.

Pr ₃ = Pr ₁ × Pr ₂

Thereafter, the human error analysis module 10 refers to a function failure data for each job, which is defined in advance, and a function that can be generated due to a human error when performing each job. Obtain information about the loss (S30).

Thereafter, the human error analysis module 10 determines the type of malfunction corresponding to each job by referring to the function failure information for each job obtained in step S30 (S35). The types of malfunctions determined here include safety-related malfunctions that directly affect the safety of nuclear power plants, such as reactor failures, and performance-related malfunctions that do not affect safety but affect the performance of nuclear power plants, such as turbine output derating. It is divided into two types. As described above, a more specific example of obtaining the type of malfunction for each job will be described in detail later.

If the type of functional loss corresponding to a specific job in step S35 is a safety-related functional loss, the safety evaluation module 20 transmits the human error probability and the functional information of the corresponding job to the safety evaluation module 20, and the safety evaluation module 20 By applying the malfunction information corresponding to the job to the deterministic model, the effect of the function failure due to human error of the job on the safety of the nuclear power plant is evaluated (S40). Here, it is preferable to use a system failure model composed of a logical combination of equipment failures that can occur in each system of a nuclear power plant as a deterministic model. The system failure model is established by a fault tree that models the structure of the system using operators such as AND, OR, and NOT by boolean logic.

When the system failure model represented by the fault tree is established, the Boolean algebra is applied to the fault tree to find the path where the system can be broken, and finally the impact on the safety of the nuclear power plant. Evaluate. For example, in the system consisting of two devices d1 and d2 as shown in (a) of FIG. 4, if both device d1 and device d2 fail, the system's function (supply of coolant from point p1 to point p2) is lost. Let's say In this case, when the malfunctioning event in which the device d1 malfunctions is called D1, the malfunctioning event in which the device d2 malfunctions is called D2, and the event that the entire system becomes inoperable is called T, when the events D1 and D2 occur simultaneously Event T will occur. Therefore, the fault tree is expressed in the form T = D1 × D2 using AND logic. This means that the path of a serious event called T consists of a malfunctioning event D1 and a malfunctioning event D2. These fault trees can be solved mathematically using Boolean algebra so that even the most complex systems can quickly calculate all possible paths of failure. Here, for modeling and analysis using the fault tree, FTREX, a high-speed fault tree quantification engine developed by the Korea Atomic Energy Research Institute, which is the applicant of the present invention, may be used.

On the other hand, if the type of malfunction corresponding to a specific job in the step S35 is a performance-related malfunction, the human error analysis module 10 delivers the information on the malfunction of the job to the performance simulation module 30, performance simulation The module 30 simulates the effect of the functional loss due to the human error of the job on the performance degradation related to the thermal efficiency of the nuclear power plant system by referring to the malfunction information corresponding to the job (S50). At this time, by simulating the thermal efficiency or the electric power that can be derived from the thermal efficiency in the nuclear power plant system, and analyzes the degree to which the human error of the job affects the performance of the nuclear power plant, that is, the output degradation . Here, the applied simulation tool can use the Performance Evaluations of Power System Efficiencies (PEPSE) developed by ScienTech in the United States for turbine cycle simulation. PEPSE solves mass and energy equations and performs turbine cycle thermal balance calculation at steady state. As a program to perform, steam turbine cycles or gas turbine cycles of any complexity can be easily simulated using a graphical interface, and the calculation speed is high.

Steps S35 to S50 are repeatedly performed for all jobs input from the user through step S10. When the safety evaluation and performance degradation simulation for each job are completed through this, the importance analysis and output module 40 is safety. The safety evaluation and performance degradation simulation results for all jobs are received from the evaluation module 20 and the performance simulation module 30, and the entire job list and the safety evaluation and performance degradation simulation results for each job are transmitted to the user through the output device. Display on the screen. Here, the importance of the overall task in terms of safety and performance of the nuclear power plant is calculated by using the human error probability of each task and the safety evaluation or performance degradation simulation results for the human error of each task, and the calculated importance of each task is calculated. It is desirable to provide the user with a list. By providing the analysis results to the user, the user can derive a method to effectively reduce the human error associated with important daily tasks based on the analysis results provided.

FIG. 5 is a diagram illustrating an example of a mapping table used in the malfunction type determining step illustrated in FIG. 2.

Referring to the mapping table shown in FIG. 5, the lowest events corresponding to malfunctions due to human error when performing a job, and upper malfunction events directly related to the malfunctions are connected by layers by logical operators.

Here, the top event is an event corresponding to an uninterrupted stop of the nuclear power plant system, and each event below the event corresponds to a malfunction of the lower device constituting the device related to the upper event. The lowest event in the column corresponds to the basic malfunction that affects the higher events.

The malfunctions corresponding to these lowest-level events are directly related to job-specific human errors specified in procedures commonly used in nuclear power plants. Therefore, in the above-described malfunction information acquisition step (S30), the malfunction information corresponding to each job information, that is, the lowest event of the mapping table, may be read and acquired from previously stored malfunction information for each job.

As described above, in the step of determining the type of malfunction (S35), the safety related events related to the malfunction due to the human error of a specific job may be identified using the mapping table as shown in FIG. 5, and the corresponding malfunction is defined in the mapping table. If it is present, it can be determined that the type of the malfunction is related to stability. On the contrary, if it is not defined in the mapping table, it can be seen that the type of the malfunction is performance related.

For example, a second-tier event, “plural system fault”, will cause the nuclear power plant to stop due to the turbine trip, which is the highest event, that is, the turbine is stopped. Looking at the third tier, “plural low vacuum” (OR) or “plural system failure” results in “plural mechanical failure” related to turbine shutdown. At this time, the "multiple low vacuum" occurs when the fourth layer "steam air ejector malfunction" and "loss of vacuum function" occur at the same time (AND), and the "loss of vacuum function" is the lowest level of "vacuum pump failed to operate". OR is generated due to "OR improper valve alignment".

Using the data in this mapping table, the malfunctions, or safety, associated with the uninterrupted shutdown of a nuclear power plant due to human errors that may occur while nuclear workers perform specific tasks for operation or maintenance. It can be determined whether the related malfunction. In other words, if a “pump fails to operate” due to any human error that may occur during the performance of the job related to the vacuum pump maintenance, this may cause a “plural system abnormality”. After determining that the type is a safety-related malfunction, the safety assessment module 20 calculates the probability of failure of the entire system due to the lowest malfunction using the tree model of the fault generated from the mapping table, and calculates the probability of human error in the job. Analyze the safety impact of On the other hand, some human error may cause “one vacuum pump loss”, which cannot be found in the mapping table, and thus may be regarded as causing a performance related function that is not related to an uninterrupted shutdown of a nuclear power plant. Therefore, by driving the performance simulation module 30 to simulate how much the electricity output due to "one vacuum pump loss", etc., it is possible to determine the importance of the job based on the results.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications, and changes are possible in the art without departing from the technical spirit of the present invention. It will be clear to those of ordinary knowledge.

1 is a block diagram of a system for evaluating human impact incidents according to an embodiment of the present invention.

2 is a flow chart illustrating a process of evaluating human-induced events in accordance with one embodiment of the present invention.

3 is a view showing an example of an input screen in the job information input step shown in FIG.

4 is a view showing the concept of the fault tree used in the safety impact analysis step shown in FIG.

FIG. 5 shows an example of a mapping table used in the malfunction type determining step shown in FIG. 2; FIG.

<Description of the symbols for the main parts of the drawings>

10: human error analysis module 20: safety evaluation module

30: performance simulation module 40: importance analysis and output module

Claims (11)

The user receives job information including job characteristics and job performance environment for daily jobs performed at a nuclear power plant, calculates a human error probability for each job by using the input job information, and defines a predefined job. A human error analysis module for acquiring malfunction information corresponding to each input job by referring to respective malfunction data; Receive each job information input by the user from the human error analysis module and the human error probability and malfunction information for each job, and apply the functional information corresponding to each job to the deterministic model A safety evaluation module for analyzing the effects of malfunctions caused by human error on each job on the safety of nuclear power plants; Receive each job information input by the user from the human error analysis module and the malfunction information for each job, the human resources of each job in terms of thermal efficiency in the nuclear power plant system based on the corresponding malfunction information for each job A performance simulation module for simulating the effects of malfunction due to errors on the deterioration of nuclear power plants; Human impact event evaluation system of a nuclear power plant, characterized in that comprises a. The method of claim 1, The human incident impact assessment system, Receive safety and performance impact analysis results for each job from the safety evaluation module and the performance simulation module, and how important each job is for the safety and performance of nuclear power plants using the delivered safety impact and performance impact analysis results. A system for evaluating the impact of a human power incident on a nuclear power plant, comprising: an importance analysis and output module configured to calculate the importance of the impact and display the analysis result including the calculated job importance to the user. . The method of claim 1, The safety evaluation module, A human-induced event impact assessment system for a nuclear power plant characterized by analyzing the safety impact of each job by a deterministic model modeled as a fault tree. In the method for evaluating the impact of human-induced events of nuclear power plants using a computer system comprising an input device, a central processing unit and an output device, Providing an input screen for inputting job information to the user, and receiving job information on the daily jobs performed at the nuclear power plant from the user through the input device; Calculating a human error probability (HEP) related to performing a corresponding job in a central processing unit using the received job information; Acquiring information on malfunctions that may be generated due to human error when performing each of the input tasks by referring to predefined malfunction data for each job; Determining, by reference to the acquired malfunction information for each job, a function failure type classified into a safety related function loss and a performance related function loss for each job; If the determined type of malfunction is a safety-related malfunction, the function of malfunction information corresponding to the job is applied to the deterministic model to evaluate the effect of the malfunction caused by human error on the job on the safety of the nuclear power plant. Steps; If the determined type of malfunction is a performance-related malfunction, simulating the effect of malfunction caused by human error on the job on performance degradation related to thermal efficiency of the nuclear power plant system by referring to the malfunction information corresponding to the job. Steps; When the safety evaluation and performance degradation simulation of the entire job inputted from the user are completed through the step of evaluating the impact on safety and simulating the impact on performance degradation, the output device displays the list of all jobs and the respective jobs. Displaying safety evaluation and degradation simulation results to a user; Human impact event impact evaluation method of a nuclear power plant, characterized in that comprises a. The method of claim 4, wherein In the step of receiving the job information through an input device, A method for evaluating the impact of human incidence events in a nuclear power plant, characterized in that a user receives job information including job name, job type information, stress level information, and error recovery information. The method of claim 5, In calculating the human error probability, Using the input job type information and stress information to calculate the job error probability of the job, from the error recovery information to calculate the recovery failure probability, the final human error probability from the product of the calculated work error probability and recovery failure probability The method of evaluating the impact of human incidence events of a nuclear power plant, characterized in that to calculate the. The method of claim 5, In the job information, A method for evaluating the impact of human incidence events on a nuclear power plant, characterized by further comprising environmental information about the space in which the job can be performed. The method of claim 4, wherein In determining the type of malfunction, Using the mapping table, which consists of the lowest level events corresponding to malfunctions due to human error during job performance and the higher level events directly related to the malfunctions, linked by hierarchy by logical operators, the type of malfunctions of each job is identified. A method for assessing the impact of human outbreaks in a nuclear power plant, characterized in that the determination. The method of claim 4, wherein In the step of evaluating the impact on the safety, A method for evaluating the impact of a human power incident on a nuclear power plant, using a deterministic system failure model, which consists of logical combinations of equipment failures occurring in each system of a nuclear power plant. The method of claim 4, wherein In the step of simulating the impact on the degradation, Human induction of a nuclear power plant characterized by simulating the thermal efficiency in the nuclear power plant system or electric power that can be derived from thermal efficiency, and analyzing the extent to which human error in the job affects the output of the nuclear power plant. Event Impact Assessment Method. The method of claim 4, wherein In the step of displaying the entire job list and the safety evaluation and performance degradation simulation results for each job to the user, Using the probability of human error in each job and the safety evaluation or performance degradation simulation results for each job, the importance of the overall job is calculated from the safety and performance aspects of the nuclear power plant. A method for evaluating the impact of human incidence events on a nuclear power plant, which is provided to the user through an output device.

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