JP4048490B2 - Power plant performance diagnostic equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a power plant performance diagnostic apparatus, and more particularly to a power plant performance diagnostic apparatus suitable for diagnosing the performance of a power plant having a steam turbine facility operated with saturated steam.
[0002]
[Prior art]
In the case of a nuclear power plant as an example of a steam turbine facility, a turbine to which saturated steam generated from a nuclear reactor is guided, a condenser for condensing steam discharged from the turbine, and a pump from the condenser through a pump. There is known one provided with a water heater that heats water supplied to a nuclear reactor (see Non-Patent Document 1).
[0003]
[Non-Patent Document 1]
Steam Engineering-Introduction to Steam Plant Engineering (Asakura Shoten) Page 100
The turbine is connected to a generator, can generate electric power by driving the turbine, and can constitute a power plant by combining steam turbine equipment and a generator.
[0004]
Conventionally, the performance of a plant is diagnosed for a plant such as a power plant (see Patent Documents 1 and 2).
[0005]
[Patent Document 1]
JP-A-8-87317 (pages 4 to 5, FIGS. 1 to 3)
[0006]
[Patent Document 2]
Japanese Patent Application Laid-Open No. 11-15516 (pages 2 to 3, FIGS. 1 to 2)
Moreover, as a device for diagnosing the performance of a plant, the device performance calculated from the process control data (process data to be processed by the process computer) is compared with the design value, and the deviation is larger than a certain judgment value. A diagnostic method for diagnosing that there is a sign of abnormality in the device has been proposed.
[0007]
Further, when diagnosing the performance of the turbine, turbine efficiency is adopted as an index of equipment performance. This turbine efficiency ηTb is adiabatic from the turbine inlet pressure Pi, the enthalpy hi, the turbine exhaust pressure Po, the enthalpy ho, and the turbine inlet pressure Pi to the exhaust pressure Po in the hs diagram representing the steam state change in the steam turbine. When the enthalpy when expanded is defined as ho ′, it is defined by the following equation.
[0008]
ηTb = UE / AE (1)
AE = hi-ho ′ (2)
UE = hi-ho (3)
That is, it is defined as the ratio between the heat drop AE of steam obtained when adiabatically expanding from the input pressure Pi to the exhaust pressure Po, and the energy UE that is actually converted into work inside the turbine.
[0009]
When using turbine efficiency for turbine performance diagnosis, steam turbine equipment operated with saturated steam requires wetness data to calculate enthalpy, and the turbine efficiency is calculated from the measured procone data. I couldn't.
[0010]
Therefore, conventionally, (1) the sample vapor is taken out from the plant, and the wetness of the sample is measured using a throttling heat flow meter or an electric heating heat flow meter, or (2) the flow rate of drain discharged from the turbine is measured. Then, heat balance calculation is performed based on this measured value and temperature to measure the wetness, or (3) the wetness is measured using the tracer technology, and the turbine efficiency is determined based on this measured wetness. A method of calculating or subtracting the total change amount of other equipment from the change amount of the entire plant performance and using the turbine performance as an index is employed (see Non-Patent Document 2).
[0011]
[Non-Patent Document 2]
JIS B 8102-1995 Steam turbine-delivery test method 4.7 Measurement of steam wetness When the wetness is measured by the method described in Non-Patent Document 2, an appropriate sample is obtained by the methods (1) and (2). However, the method (3) is not implemented in normal monitoring work because of the large measuring equipment.
[0012]
Furthermore, in the conventional method, when a system abnormality such as a steam leak occurs, it is necessary to investigate the piping temperature and abnormal noise in addition to the process control data in order to determine the system where the abnormality has occurred. .
[0013]
[Problems to be solved by the invention]
In the conventional technology, measurement data other than procone data is required for calculating turbine efficiency and diagnosing system abnormalities. In normal plant diagnosis work, this is done from the viewpoint of cost and burden on workers. Not done.
[0014]
Also, in the diagnosis of system abnormal locations, it is necessary to enter a high-dose range in order to identify abnormal locations, and to install and investigate instruments, increasing the burden on the operator.
[0015]
An object of the present invention is to determine the turbine efficiency based on the process data without determining the wetness, and to enable performance diagnosis of the power plant, and to diagnose the cause of the abnormality when a system abnormality occurs based on the process data. It is to be able to do .
[0016]
[Means for Solving the Problems]
In order to solve the above problems, power plant performance diagnostic apparatus of the present invention, the steam-based saturated steam from the saturated steam source for driving the steam turbine have guide to the condenser through the steam turbine and the condensate and process data input means for process data are entered measured for water supply system for supplying water to said saturated steam source via a feed water heater from the vessel,
Performance data generating means for generating performance data by processing the process data input from the process data input means, such as average value processing ,
Heat balance calculation for calculating process data by executing heat balance calculation for the steam system and water supply system based on the heat output of the saturated steam generation source based on the performance data generated by the performance data generation means Means,
Generator output calculating means for calculating the output of the generator connected to the steam turbine based on the process data calculated by the heat balance calculating means and the set turbine efficiency ;
It is determined whether or not a deviation between the output of the generator calculated by the generator output calculation means and the actual output of the generator connected to the steam turbine is within an allowable range, and the deviation is within the allowable range. When it is determined that the set turbine efficiency is true, the set turbine efficiency is set to the true turbine efficiency. Otherwise, the set turbine efficiency is updated, and the generator output calculation means causes the deviation of the generator output to be within the allowable range. A diagnostic means for repeatedly executing the calculation until entering to obtain the true turbine efficiency,
Abnormal event model data storage means in which deviation model data obtained by simulation by heat balance calculation based on design data is stored for system abnormal events predicted in advance based on design data;
Deviation data generating means for generating deviation data between the performance data generated by the performance data generating means and the process data calculated by the heat balance calculating means;
Comparing the deviation data generated by the deviation data generation means with the deviation model data stored in the abnormal event model data storage means, and comprising an abnormality factor diagnosis processing means for diagnosing an abnormality factor Features.
[0017]
When configuring the plant performance diagnostic device, the deviation between the output of the generator calculated by the generator output calculation means and the actual output of the generator connected to the steam turbine is an allowable range instead of the comparison means. It is possible to adopt a configuration including a determination unit that determines whether or not the output is within the range and outputs the determination result. In this case, the determination means sets the turbine efficiency to the true turbine efficiency when it is determined that the deviation is within the allowable range, and updates the turbine efficiency otherwise, and the heat balance calculation means and the power generation When the turbine efficiency is updated, the machine output calculation means may be configured to repeatedly execute the calculation according to the updated turbine efficiency until a positive determination result is output from the determination means. it can.
[0020]
Since it has such a feature, it calculates the output of the generator based on the process data obtained by the heat balance calculation and setting the turbine efficiency, compared with the actual output of which and the generator, the result of the comparison Is within the allowable range, the set turbine efficiency is set to the true turbine efficiency . When the comparison result is out of the allowable range, the turbine efficiency is updated until the comparison result is within the allowable range, and the true turbine efficiency is obtained. Can do.
[0021]
As a result, without requiring the humidity Ri degree, it can be based on process data obtaining turbine efficiency.
[0022]
Moreover, a system abnormal event can be diagnosed by comparing a model prepared in advance with respect to an assumed plant system abnormal event and actual operation data.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an embodiment when the present invention is applied to a nuclear power plant. In FIG. 1, a plant performance diagnosis apparatus 100 includes a process computer and a database as main components. The process computer includes a process control data acquisition processing unit 1, a performance data processing unit 2, a data reading correction processing unit 3, and a heat. It functions as a balance calculation processing means 4, a turbine efficiency calculation processing means 5, a deviation data creation processing means 6, and an abnormality factor diagnosis processing means 7. The abnormality factor diagnosis processing means 7 is displayed via an output processing means 14, It is connected to an output device such as a printer.
[0024]
On the other hand, the database functions as the process control data storage means 8, the design data storage means 9, the performance data storage means 10, the HB (heat balance) data storage means 11, the deviation data storage means 12, and the abnormal event model data storage means 13. It is prepared for.
[0025]
For example, as shown in FIG. 2, the nuclear power plant includes a recirculation pump 30, a nuclear reactor 32, a high-pressure steam turbine 34, a moisture separator 36, a low-pressure steam turbine 38, a condenser 40, a condensate pump 42, a low-pressure A feed water heater 44, a feed water pump 46, and a high pressure feed water heater 48 are provided. The nuclear reactor 32 is configured as a saturated steam generation source, and the saturated steam generated from the nuclear reactor 32 is guided to the condenser 40 via the high pressure steam turbine 34, the moisture separator 36, and the low pressure steam turbine 38. ing. The water discharged from the condenser 40 is introduced into the low-pressure feed water heater 44 by the drive of the condensate pump 42 and heated by the low-pressure feed water heater 44. The heated water is introduced into the high-pressure feed water heater 48 by driving the feed water pump 46, heated by the high-pressure feed water heater 48, and then fed into the reactor 32. That is, a steam system including a high-pressure steam turbine 34, a moisture separator 36, a low-pressure steam turbine 38, and a condenser 44 is connected to the saturated steam outlet side of the reactor 32, and the water supply side of the reactor 32 is A water supply system including a high-pressure feed water heater 48, a feed water pump 46, a low-pressure feed water heater 44, and a condensate pump 42 is connected. A generator (not shown) is connected in series to the high-pressure steam turbine 34 and the low-pressure steam turbine 38 via a drive shaft. In addition, although the thing of a single system is shown, the water supply system is actually divided into a plurality of systems, and each water supply system is connected in parallel.
[0026]
Process data regarding each state of elements belonging to the steam system and the feed water system in the nuclear power plant shown in FIG. 2 is processed by a process computer (hereinafter referred to as “procon data”). 1 is entered. The process control data includes the feed water flow rate of the low pressure feed water heaters 44 and 48, the feed water temperature, the feed water flow rate of the feed water pump 46, the flow rate of steam introduced into the high pressure steam turbine 34 and the low pressure steam turbine 38, and the condenser 40 There is data on the degree of vacuum (pressure), etc., and each piece of process control data is input to a process computer from a sensor or a measuring instrument installed in each part, and the input process control data is stored in the process control data storage means 8.
[0027]
The process control data stored in the process control data storage means 8 is subjected to processing such as instrumental error correction and averaging based on the design data stored in the design data storage means 9 and stored in the performance data storage means 10 as performance data. Is done. The performance data stored in the performance data storage means 10 is compared with the design data stored in the design data storage means 9 by the data reading correction processing means 3. Here, when the deviation between the performance data and the design data exceeds the set value, the design data is selected. Otherwise, the performance data is selected, and the data read by the data reading correction processing means 3 is subjected to heat balance calculation processing. Output to means 4.
[0028]
The heat balance calculation processing means 4 serves as heat balance calculation means such as data from the data reading correction processing means 3 and pipe pressure loss data, turbine stage pressure initial value data, etc., among the design data stored in the design data storage means 9. Based on the data, the heat balance calculation for the steam system and the water supply system is executed based on the heat output of the reactor 32, and the heat amount of the entire system including the steam system and the water supply system is calculated (the heat output of the reactor 32 and The heat balance calculation in each part is performed so that the heat quantity of the entire system becomes equal, and the calculation result is stored in the HB data storage means 11.
[0029]
The turbine efficiency calculation processing means 5 takes in the processing result of the heat balance calculation processing means 4 and the data stored in the HB data storage means 11 and is set as the turbine efficiency among the design data stored in the design data storage means 9. Function of the generator output calculation means to calculate the output of the generator based on the heat quantity of the entire system by heat balance calculation and the set turbine efficiency. It is configured to have a function as comparison means for comparing the output and the actual output of the generator and outputting the comparison result to a display or the like via the output processing means 14. Further, the turbine efficiency calculation processing means 5 determines whether or not the deviation between the calculated output of the generator and the actual output of the generator is within an allowable range and displays the determination result via the output processing means 14. Etc., and is provided with a function as a determination means for outputting to the above. In this case, as the determination means, when it is determined that the deviation is within the allowable range, the set turbine efficiency is set to the true turbine efficiency, otherwise, the turbine efficiency is updated, and the generator Until the deviation between the output and the actual output of the generator falls within the allowable range (until a positive determination result is output from the determination means), the output of the generator is calculated according to the updated turbine efficiency, and the heat A command for repeatedly executing the heat balance calculation is output to the balance calculation processing means 4.
[0030]
Specifically, when obtaining the turbine efficiency, as shown in FIG. 3, when processing for obtaining the turbine efficiency is started, a counter of the process computer is initialized (m is set to 0) (step S1). 4) An input data confirmation screen as shown in FIG. 4 is displayed on the display screen of the process computer. If an operation for designating the date is performed at this time, the date is displayed in the designated display area (step S2). Thereafter, performance data and design data are read (step S3), and processing for correcting input data among the read data is performed as necessary (step S4). When the correction of the input data is completed, the calculation regarding the heat balance is started.
[0031]
In this case, the heat balance calculation for the steam system and the water supply system is executed based on the input process control data on the basis of the heat output of the reactor 32, and the heat quantity of the entire system including the steam system and the water supply system is obtained. (Step S5). That is, the convergence calculation is performed with the heat output suppressed so that the heat output of the reactor 32 and the heat amount of the entire system including the steam system and the water supply system other than the reactor 32 are equal. Thereafter, it is determined whether or not the number of heat balance calculations has reached a predetermined number (step S6). If the predetermined number of times has not been reached, the amount of heat of the entire system obtained by the heat balance calculation is set. Multiply the efficiency (%) to find the generator output (electrical output). At this time, the actual output of the generator is taken in, and it is determined whether or not the deviation between the calculated output of the generator and the actual output of the generator is within an allowable range (step S7). That is, it is determined whether or not the output (electrical output) of the generator obtained by the calculation is equal to or less than the actual electrical output + ε and equal to or greater than −ε of the actual generator output. If the generator output by calculation is within the actual electrical output ± ε of the generator, it is determined that the preset turbine efficiency is appropriate, that is, the true turbine efficiency, and the process is terminated.
[0032]
On the other hand, when the generator output (electrical output) calculated is outside the actual electrical output ± ε of the generator, the turbine efficiency is updated (corrected) (step S8), the counter is set to m + 1, and the process returns to step S5. That is, when the turbine efficiency is updated, a process for repeating the heat balance calculation and the generator output calculation is performed until the turbine efficiency becomes an appropriate value. The update calculation at this time is the original turbine efficiency (initially set turbine efficiency) ηTb, the updated turbine efficiency ηc, the actual electrical output (actual generator output) KWEr, and the calculated generator output ( Electrical output) is KWEc, and the correction coefficient is c.
[0033]
c = KWEr / KWEc (4)
ηc = ηTb × c (5)
When it is determined (determined) that the turbine efficiency is appropriate, the turbine efficiency is defined as the actual turbine efficiency, and the result is output to a display or a printer and stored in the HB data storage unit 11. When the turbine efficiency is stored along the time axis, the turbine efficiency is output to a display or printer as a trend diagram as shown in FIG. By monitoring the turbine efficiency according to this trend diagram, it is possible to grasp the performance change of the turbine.
[0034]
On the other hand, the deviation data creation processing means 6 fetches the performance data of the date to be diagnosed from the performance data storage means 10, and the data related to the processing result of the turbine efficiency calculation processing means 5 from the HB data storage means 11 and heat balance calculation. It is configured to have a function as a deviation data generation unit that takes in data relating to the processing result of the processing unit 4, generates deviation data indicating each deviation for main data, and stores the generated deviation data in the deviation data storage unit 12. ing. The deviation data generated by the deviation data creation processing unit 6 is output to a display, a printer, or the like via the output processing unit 14. For example, as shown in FIG. 6, deviation data such as pressure balance in the feed water heater, feed water / feed water flow rate balance, condensate / feed water temperature balance, and the like are displayed.
[0035]
The abnormal factor diagnosis processing means 7 diagnoses an abnormal factor related to the diagnosis object based on the deviation data stored in the deviation data storage means 12 and the abnormal event model data stored in the abnormal event model data storage means 13; The diagnosis result is output to a display, a printer or the like via the output processing means 14. The abnormal event model data storage means 13 stores deviation model data obtained by simulating a system abnormal event that can be assumed in advance based on the design HB. When the deviation model data is stored, as shown in FIG. 7, as an abnormal system event that can be assumed in advance by the assumed abnormal event input means 15, for example, a turbine efficiency decrease event, a main steam leak event, a cross-around leak event Information regarding the system abnormal event input by the assumed abnormal event input means 15 and the calculation condition of the design HB (heat balance) stored in the design data storage means 9 In means 4, heat balance calculation is performed for each abnormal event. For example, heat balance calculation is performed assuming that main steam has leaked from the path connecting the reactor 32 and the high pressure steam turbine 34, or steam is generated from the path connecting the moisture separator 36 and the low pressure steam turbine 38. For example, a heat balance calculation is performed assuming a cross-around leak event, and each calculation result is output to the data comparison processing means 16. In the data comparison processing means 16, the heat balance calculation result in the normal state is fetched from the heat balance calculation processing means 14, the abnormal event simulation calculation is performed, and this calculation result and main data of the design HB stored in the design data storage means 9 The deviation is calculated for each and stored in the abnormal event model data storage means 13 as model data of the abnormal event assuming this deviation. The abnormal event model data stored in the abnormal event model data storage unit 13 is output to the abnormal factor diagnosis processing unit 7. The abnormal factor diagnosis processing means 7 compares the abnormal event model data stored in the abnormal event model data storage means 13 with the deviation data stored in the deviation data storage means 17, and the comparison result is output via the output processing means 14. Output to a display or printer.
[0036]
Here, one example of abnormal event model data is shown in FIGS. The abnormal event model data in FIG. 8 is data related to the turbine efficiency reduction event, the abnormal event model data shown in FIG. 9 is data related to the main steam leak event, and the abnormal event model data in FIG. 10 is data related to the cross-around leak event. is there.
[0037]
Further, when a simulation was performed on a cross-around leak event, as shown in FIG. 11, before the leak was assumed (before the simulation), there was a large deviation in the pressure balance in the feed water heater and the condensate / feed water flow rate balance. However, after the simulation after recalculating the heat balance assuming leaks, the deviations in the pressure balance in the feed water heater and the condensate / feed water flow rate balance became smaller, and the actual state was approached. I understand that. In other words, since the model data shows a characteristic pattern for each assumed abnormal event, comparing the model data with the deviation data indicates that the event indicated by the pattern based on the comparison result is a factor of performance change. Can be diagnosed.
[0038]
According to the present embodiment, it is possible to obtain the turbine efficiency based on the process control data without obtaining the wetness or performing a special test, and it is possible to monitor the transition of the turbine efficiency. Turbine maintenance plan can be optimized.
[0039]
In addition, according to the present embodiment, the cause of the performance change due to the system abnormality can be diagnosed from the process data, so that an abnormal event can be detected and dealt with early. Furthermore, in order to diagnose the performance of the plant, the number of times the worker enters the high dose range can be reduced.
[0040]
【The invention's effect】
As described above, according to the present invention, the turbine efficiency can be obtained based on the process data without obtaining the wetness.
[Brief description of the drawings]
FIG. 1 is a block configuration diagram of a power plant performance diagnostic apparatus showing an embodiment of the present invention.
FIG. 2 is a block diagram of a power plant.
FIG. 3 is a flowchart for explaining a processing method for obtaining heat balance and turbine efficiency.
FIG. 4 is a diagram showing a display example of an input data confirmation screen.
FIG. 5 is a trend diagram of turbine efficiency.
FIG. 6 is a diagram showing a display example of deviation data.
FIG. 7 is a flowchart for explaining a processing procedure for creating abnormal event model data;
FIG. 8 is a diagram showing a display example of abnormal event model data related to a turbine efficiency reduction event.
FIG. 9 is a display example of abnormal event model data related to a main steam leak event.
FIG. 10 is a diagram illustrating a display example of abnormal event model data related to a cross-around leak event.
FIG. 11 is a diagram showing a display example of a simulation result when a cross-around leak is assumed.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Procon data acquisition processing means 2 Performance data processing means 3 Data reading correction processing means 4 Heat balance calculation processing means 5 Turbine efficiency calculation processing means 6 Deviation data creation processing means 7 Abnormal factor diagnosis processing means 8 Procon data storage means 9 Design data Storage means 10 Performance data storage means 11 HB data storage means 12 Deviation data storage means 13 Abnormal event model data storage means 14 Output processing means 32 Reactor 34 High pressure steam turbine 36 Moisture separator 38 Low pressure steam turbine 40 Condenser 42 Recovery Water pump 44 Low pressure feed water heater 46 Feed water pump 48 High pressure feed water heater 100 Power plant performance diagnosis device

Claims (1)

Feed water system for supplying water saturated steam from the saturated steam generating source to the saturated vapor source through a feedwater heater from the steam system and the condenser to drive the steam turbine have guide to the condenser via the steam turbine and process data input means for process data are entered measured for,
Performance data generating means for generating performance data by processing the process data input from the process data input means, such as an average value processing ;
Heat balance calculation for calculating process data by executing heat balance calculation for the steam system and water supply system based on the heat output of the saturated steam generation source based on the performance data generated by the performance data generation means Means,
Generator output calculating means for calculating the output of the generator connected to the steam turbine based on the process data calculated by the heat balance calculating means and the set turbine efficiency ;
It is determined whether or not a deviation between the output of the generator calculated by the generator output calculation means and the actual output of the generator connected to the steam turbine is within an allowable range, and the deviation is within the allowable range. When it is determined that the set turbine efficiency is true, the set turbine efficiency is set to the true turbine efficiency. Otherwise, the set turbine efficiency is updated, and the generator output calculation means causes the deviation of the generator output to be within the allowable range. A diagnostic means for repeatedly executing the calculation until entering to obtain the true turbine efficiency,
Abnormal event model data storage means for storing deviation model data obtained by simulation by heat balance calculation based on design data for system abnormal events predicted based on design data in advance,
Deviation data generation means for generating deviation data between the performance data generated by the performance data generation means and the process data calculated by the heat balance calculation means;
Power plant performance comprising an abnormality factor diagnosis processing means for diagnosing an abnormality factor by comparing the deviation data generated by the deviation data generation means and the deviation model data stored in the abnormal event model data storage means Diagnostic device.

Images