JP2004094453A - Plant design support system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plant design support system optimizing a design change without being biased toward the cost by taking account of a breakdown probability in the design change in the plant structure. <P>SOLUTION: While a risk caused by the design change is numeralized by numeralizing the breakdown probability when the structural design is changed based on past design data and past accident information related to the plant, the numeric data is compared with a cost merit caused by the design change so as to provide the maximum cost merit. This constitution optimizes the design change. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a plant design support system, and is particularly useful when applied to optimize the design of a plant as an aggregate of many devices such as a thermal power plant.
[0002]
[Prior art]
Design of large plants such as thermal power plants should be performed by appropriately changing each design data while using past design data of each device constituting the plant so as to obtain an optimal design according to the specifications. It is customary. At this time, if there are new materials, new structures, and new construction methods at the time of design, the adoption of these materials will also be considered.
[0003]
[Problems to be solved by the invention]
In the plant design as described above, when changing the structure and adopting a new material, a new structure, and a new construction method, only the cost merit has been conventionally evaluated, and the quantitative evaluation and optimization of the risk have not been performed. For this reason, when a trouble after the start of operation occurs due to a design change or the like, a loss exceeding the cost merit due to the design change is often caused to cope with the trouble.
[0004]
Therefore, when a plant design change is made, it is necessary to make an optimum design change in consideration of the structural change and the risks predicted by the adoption of a new material / new structure / new construction method.
[0005]
In view of the above prior art, an object of the present invention is to provide a plant design support system capable of optimizing a design change without biasing only to cost by considering a failure probability accompanying a design change of a plant structure. And
[0006]
[Means for Solving the Problems]
The configuration of the present invention that achieves the above object has the following features.
[0007]
1) accident information storage means for storing information on past accidents, such as the occurrence of an accident in a plant such as a thermal power plant, the time at which the accident occurred, the number of startups when the accident occurred, and the like;
Design data storage means for storing past design data related to the structure, temperature, stress, design life, etc. of the plant,
Cost data storage means for storing cost data relating to the product price of the plant, the amount of loss in the event of an accident, etc.
While reading the structural design data at the time of performing the actual structural design of the plant, read the data of the accident information storage means and the design data storage means and read the probability of destruction of the plant accompanying the design change at the time of the structural design. Calculating a destruction probability calculating means;
While reading the data regarding the destruction probability calculated by the destruction probability calculation means and the cost data stored in the cost data storage means, the risk obtained by multiplying the destruction probability and the loss is quantified while the design change is performed. Product value analysis means for quantifying profits such as cost reduction accompanying the numerical value, and analyzing the initial product value by subtracting the numerical value of the risk from this numerical value,
Optimizing means for changing the structural design, repeating the calculation of the fracture probability and analyzing the initial product value with respect to the changed structural design, and setting a structural design condition that gives the greatest benefit as a result.
[0008]
2) In the plant design support system described in 1) above,
The optimizing means should be set so as to maximize both profits in consideration of the profit on the manufacturing side of the plant and the profit on the consumer side of the plant.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to FIG.
[0010]
The plant structural design (see step S1) is performed based on, for example, the plant structure, temperature, stress conditions, and the like. That is, the thickness, size, material, and the like are determined in the structure, and the temperature, for example, the steam temperature and the pressure of the thermal power plant are considered. The stress condition is determined by the allowable stress, and the material to be used is determined if the allowable stress is determined.
[0011]
The plant design support system according to the present embodiment includes a design data storage unit 1, an accident information storage unit 2, a cost data storage unit 3, and a calculation unit 4.
[0012]
The design data storage unit 1 stores past design data relating to the structure, temperature, stress, design life, and the like of a plant such as a thermal power plant. In the case of the plant, that is, in the case of a thermal power plant, the design data is individually accumulated for each device constituting the plant, such as a boiler, a turbine, and piping.
[0013]
The accident information storage unit 2 stores information about an accident that has occurred in the past, such as an event that occurred in the plant, the time at which the accident occurred, the number of startups when the accident occurred, and the like. More specifically, past accident information related to a change in welding, a change in heat treatment, a change in inspection method, or the like due to a design change, for example, is stored. Thus, when the content of the design change is specified, accident information related to the design change can be made to correspond, and this can contribute to predicting the probability of an accident caused by the design change.
[0014]
The cost data storage unit 3 stores cost data relating to the product price of the plant, the amount of loss in the event of an accident, and the like. Here, the loss amount at the time of the accident includes, in the event that an accident occurs, the cost including the labor cost, material cost, etc. for restoring the accident, as well as the loss due to stopping the plant. .
[0015]
The calculation unit 4 includes a destruction probability calculation unit 4a, a product value analysis unit 4b, and an optimization unit 4c.
[0016]
Here, the fracture probability calculation unit 4a reads the structural design data when the actual structural design of the plant is performed, and reads the data of the design data storage unit 1 and the accident information storage unit 2 to read the structural design data. The probability of destruction of the plant accompanying the design change at the time is calculated. That is, a change in stress, temperature condition, or the like due to a structural change is quantified as a fracture probability. As a result, the risk of structural change at the time of design can be quantified as the destruction probability.
[0017]
The method of calculating the destruction probability will be described in detail. Assuming that the probability that the i-th part constituting the product fails after t hours is Pfti, and the total loss such as loss due to operation stop caused by failure of the i-th part and repair work is Wi, The risk Rti (amount) after t hours of the product is
Rti = Wi × Pfti
It becomes.
[0018]
Assuming that the cost reduction (benefit amount) caused by the design change of the part is Ci and the increase in the failure probability due to the design change is ΔPfti, the increase in risk ΔRti due to the design change is:
ΔRti = Wi × ΔPfti
It becomes.
[0019]
Numerical value Di obtained by subtracting risk from the merit of the design change, that is, Di = Ci−ΔRti
Is the real benefit of a design change.
[0020]
Generally, the probability of failure increases rapidly as the operating time t increases, but the probability of failure decreases in a short time. In order to reduce the initial cost, it is advantageous to increase the value of Ci by making a design change. Conversely, when emphasizing reliability during long-time operation, the design should be changed as much as possible even if the initial cost is increased. It can be said that it is desirable to adopt a proven structure with a minimum and minimize the increase in risk ΔRti. Similarly, it is possible to optimally change the design in accordance with the required specifications from the relationship between the merit and the risk.
[0021]
The product value analysis unit 4b reads the data on the failure probability calculated by the failure probability calculation unit 4a and the cost data stored in the cost data storage unit 3, and calculates the product value accompanying the design change. Further, specifically, while adding the merit generated by the structural change to the conventional cost, the product value in this case is determined by subtracting the amount obtained by multiplying the loss amount at the time of the accident by the probability of destruction. That is, while quantifying the risk obtained by multiplying the destruction probability and the loss, quantifying the profit such as cost reduction due to the design change, and subtracting the risk value from this value to analyze the initial product value. Do [0022]
The optimizing unit 4c changes the structural design, and repeats the calculation of the fracture probability and the analysis of the initial product value for the changed structural design, thereby setting the structural design conditions with the highest profit. Here, the optimization unit 4c according to the present embodiment considers the profit on the manufacturing side of the plant and the profit on the consumer side of the plant and sets the profits of both sides to be maximum. Here, the profit on the consumer side refers to the total satisfaction based on the demand for the plant. For example, the life of the plant may be short, but if there is a demand to make the cost as low as possible, a design using many materials with a short life but low cost may be used. Therefore, this is realized by performing a process such as multiplying an appropriate parameter at the time of evaluating the product value by the product value analysis unit 4b with a weighting factor in consideration of the priority order reflecting the demand of the consumer side. obtain.
[0023]
According to the plant design support system of the present embodiment, considering the probability of destruction due to the design change, that is, without biasing only to the cost merit due to the design change, comprehensive processing of the design change is performed by processing the numerical values taking the demerits into consideration. Evaluation can be performed.
[0024]
【The invention's effect】
As described in detail with the above embodiments, the invention described in [Claim 1] is applicable to a plant such as a thermal power plant, in which an accident occurrence event, an accident occurrence time, the number of startups when the accident occurs, etc. Accident information storage means for storing information on accidents that occurred in the past; design data storage means for storing past design data relating to the structure, temperature, stress, design life, etc. of the plant; and products of the plant. Cost data storage means for storing cost data relating to price, loss amount at the time of accident, etc., and reading the structural design data when an actual structural design of the plant is performed, and storing the accident information storage means and design data storage A destruction probability calculating means for reading data of the means and calculating a destruction probability of the plant accompanying a design change at the time of the structural design; The data relating to the failure probability calculated by the rate calculation means and the cost data stored in the cost data storage means are read, and the risk obtained by multiplying the failure probability by the loss is quantified, while the risk associated with the design change is changed. Product value analysis means for quantifying profits such as cost reduction and subtracting the value of the risk from this value to analyze the initial product value, and changing the structural design, and changing the probability of failure with respect to the changed structural design. Since the calculation and the analysis of the initial product value are repeated, and as a result, there is an optimization means for setting the structural design condition having the greatest profit,
Comprehensive evaluation of the design change can be performed by processing numerical values in consideration of the demerit probability associated with the design change, that is, without deviating only to the cost merit accompanying the design change, but also taking into consideration the demerits.
As a result, it is possible to determine the suitability or unsuitability of the design change from the viewpoint of comprehensive merits and demerits, and to optimize the design.
In other words, there is a merit by predicting the probability of occurrence of the risks predicted by structural changes and adopting new materials, new structures and new construction methods from past accident data, and considering the amount corresponding to the probability as a loss in advance. Optimal design that quantitatively evaluates both the disadvantages and disadvantages becomes possible.
Incidentally, it is imperative for the consumer to make the required operation time free of accidents, and excessive investment exceeding that requirement can be avoided. On the other hand, the manufacturing side can make a design change according to the demands of the consumer side, and reduce the initial cost according to the required operation time.
According to the present invention, since the merits and risks are expressed in monetary values, design changes can be made in accordance with operating conditions based on the magnitude relationship, and consensus between the manufacturing side and the consumer side can be easily formed. it can.
[0025]
The invention described in [Claim 2] is a plant design support system according to [Claim 1], wherein the optimization means considers the profit on the manufacturing side of the plant and the profit on the consumer side of the plant. So that the profits of both parties are maximized,
In addition to the functions and effects of the invention described in [Claim 1], both the manufacturing side and the consumer side can contribute to the optimal design so as to obtain the best profit at the same time.
[Brief description of the drawings]
FIG. 1 is a flowchart showing a processing procedure of a plant design support system according to the present invention.
[Explanation of symbols]
S1 Structural design 1 Design data storage unit 2 Accident information storage unit 3 Cost data storage unit 4 Operation unit 4a Destruction probability operation unit 4b Product evaluation analysis unit 4c Optimization unit

Claims (2)

Accident information storage means for storing information on accidents that have occurred in the past, such as the occurrence of an accident in a plant such as a thermal power plant, the time when the accident occurred, the number of startups when the accident occurred, and the like;
Design data storage means for storing past design data related to the structure, temperature, stress, design life, etc. of the plant,
Cost data storage means for storing cost data relating to the product price of the plant, the amount of loss in the event of an accident, etc.
While reading the structural design data at the time of performing the actual structural design of the plant, read the data of the accident information storage means and the design data storage means and read the probability of destruction of the plant accompanying the design change at the time of the structural design. Calculating a destruction probability calculating means;
While reading the data regarding the destruction probability calculated by the destruction probability calculation means and the cost data stored in the cost data storage means, the risk obtained by multiplying the destruction probability and the loss is quantified while the design change is performed. Product value analysis means for quantifying profits such as cost reduction accompanying the numerical value, and analyzing the initial product value by subtracting the numerical value of the risk from this numerical value,
Optimizing means for changing the structural design, repeating the calculation of the fracture probability and the analysis of the initial product value with respect to the changed structural design, and setting a structural design condition with the highest profit as a result. Plant design support system. In the plant design support system according to claim 1,
A plant design support system characterized in that the optimizing means takes into consideration the profit on the manufacturing side of the plant and the profit on the consumer side of the plant and sets the profits of both to the maximum.

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