JP2016133279A - Steam valve diagnosis device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To diagnose occurrence of steam leakage from a steam valve extremely simply without requiring a large workload in advance.SOLUTION: An operation situation detection unit 13 detects reduction degree Δ of inside air temperature T in an operation stop period L from the time of stopping operation of an air conditioner 20 until the time of resuming operation, from an operation history recorded in an operation history DB 12. A steam valve diagnosis unit 15 diagnoses the presence/absence of probability of steam leakage in a steam valve 32 by comparing the reduction degree Δ with a normal range Δn.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a valve diagnosis technique, and more particularly to a steam valve diagnosis technique for diagnosing a steam valve that adjusts the flow rate of steam supplied from a steam boiler to a heating coil of an air conditioner.

  In a relatively large facility such as a tenant building, shopping center, or hospital, a central air conditioning system using steam is widely used to efficiently heat a plurality of sections. In such an air conditioning system, a heating coil is provided in the air conditioner, the steam from the steam boiler is supplied to the heating coil via the steam pipe, and the air to be blown is heated by heat exchange by the heating coil and then passed through the duct. Supply to the room of each compartment. At this time, the steam that has exchanged heat with the heating coil condenses into water, and is boosted by a booster pump and returned to the steam boiler. Moreover, a part of the steam from the steam boiler is supplied to the humidifier via the humidifying valve, and the air supplied into the compartments is humidified.

  In such an air conditioning system, a steam valve comprising a flow rate adjusting valve for adjusting the flow rate of steam is provided between the steam boiler and the heating coil, and the temperature of air supplied from the heating coil to the room through the duct is measured. The opening of the steam valve is adjusted by this temperature. Thereby, since the flow volume of the steam supplied to the heating coil is adjusted by the opening degree of the steam valve, the room temperature is controlled to an appropriate temperature as a result.

Japanese Patent Application Laid-Open No. 11-63520

  In the air conditioning system described above, the steam valve is fully closed during the time when the air conditioner is not operating, but if it is necessary to supply steam to other operating air conditioners, etc., the steam boiler must be kept in operation. ing. In such a case, steam may leak from the steam valve that should be fully closed due to deterioration of the steam valve or the like and supplied to the heating coil. At this time, since the air conditioner is not in operation and the blower is also stopped, the heat exchanged with the steam supplied to the heating coil is accumulated in the air conditioner, and the internal temperature of the air conditioner is higher than usual. There is a problem that it rises and causes problems such as deformation of parts used in the air conditioner.

  Even if the air conditioner is in operation, if the opening degree of the steam valve cannot be accurately adjusted due to deterioration of the steam valve or the like, the air conditioning control cannot be performed properly. In particular, if steam leaks during cooling when the steam valve is fully closed, the leaked steam is supplied to the heating coil and the air is heated. Therefore, it is necessary to cool the air with the cooling coil by this amount of heating, which is wasteful. There was a problem of consuming a lot of energy.

  For this reason, conventionally, in such an air conditioning system, the change over time of the internal air temperature of the air conditioner is predicted using a mathematical model, and the leakage amount of the steam valve is predicted without using a flow meter. There has been proposed one that enables appropriate replacement and repair (see, for example, Patent Document 1).

  However, according to such a conventional technique, in order to accurately predict the change over time in the internal air temperature and the leakage amount of the steam valve, parameters such as the time constant of the internal air temperature of the air conditioner are repeated by repeating experiments in advance. Must be analyzed accurately. For this reason, the method for predicting the leakage amount of the steam valve as in the prior art has a problem that a large work load is required in advance.

  The present invention is for solving such problems, and it is extremely simple to diagnose the occurrence of steam leakage from the steam valve without requiring a large work burden in advance. The purpose is to provide.

  In order to achieve such an object, a steam valve diagnostic apparatus for diagnosing steam leakage in a steam valve that adjusts the flow rate of steam supplied from a steam boiler according to the present invention to a heating coil of an air conditioner, The operation history recording unit that periodically collects the start and stop of the machine and the internal air temperature in the vicinity of the heating coil and records it as the operation history of the air conditioner, and from the recorded operation history, the air conditioner An operating condition detection unit that detects the degree of decrease in the internal air temperature during an operation stop period from when the operation is stopped to when it is restarted, and a range in which the degree of decrease can be taken when there is no steam leakage in the steam valve. By comparing the normal range with a normal range setting unit that sets as a normal range, the detected degree of decrease and the normal range are diagnosed. And a steam valve diagnostic unit.

  Further, in one configuration example of the steam valve diagnostic device according to the present invention, the operating state detection unit detects a decrease temperature range of the internal air temperature during the operation stop period as the decrease degree, and the normal range setting unit Sets, as the normal range, a normal decrease temperature range related to the decrease temperature range during the operation stop period, and the steam valve diagnosis unit does not include the detected decrease temperature range in the normal decrease temperature range In this case, it is diagnosed that there is a possibility of steam leakage in the steam valve.

  Also, in one configuration example of the steam valve diagnostic device according to the present invention, the operating state detection unit detects a decrease temperature range of the internal air temperature per unit time as the decrease degree, and the normal range setting unit includes When the normal temperature range is set as the normal range, the normal temperature range is related to the temperature range per unit time, and the steam valve diagnosis unit is not included in the normal temperature range. In this case, it is diagnosed that there is a possibility of steam leakage in the steam valve.

  Further, in the configuration example of the steam valve diagnostic device according to the present invention, the operating state detection unit detects the rate of decrease of the internal air temperature as the degree of decrease, and the normal range setting unit sets the normal range as the normal range. A normal reduction rate range related to the reduction rate is set, and the steam valve diagnosis unit, when the detected reduction rate is not included in the normal reduction rate range, there is a possibility of steam leakage in the steam valve. Diagnosis is made.

  Further, in the configuration example of the steam valve diagnostic device according to the present invention, the operating state detection unit detects the internal air temperature when the air conditioner is restarted as the degree of decrease, and the normal range setting unit is The determination threshold value indicating a normal internal air temperature range related to the internal air temperature at the time of restarting operation is set, and the steam valve diagnosis unit does not include the detected internal air temperature in the normal internal air temperature range In this case, it is diagnosed that there is a possibility of steam leakage in the steam valve.

  A steam valve diagnostic apparatus method according to the present invention is a steam valve diagnostic method for diagnosing steam leakage in a steam valve for adjusting a flow rate of steam supplied from a steam boiler to a heating coil of an air conditioner, wherein the air conditioner The operation history recording step of periodically collecting the operation start and operation stop and the internal air temperature in the vicinity of the heating coil and recording it as the operation history of the air conditioner, and the air conditioner operates from the recorded operation history The operation state detection step for detecting the degree of decrease in the internal air temperature during the operation stop period from when the operation is stopped to when the operation is restarted, and the range that the degree of decrease can take when the steam valve is normal and without steam leakage A normal range setting step for setting as a range, and by comparing the detected degree of decrease with the normal range, steam leakage in the steam valve is possible. And a steam valve diagnostic step of diagnosing the presence or absence.

According to the present invention, parameters such as the time constant of the internal air temperature of the air conditioner are accurately determined by repeating the experiment in advance, as in the case of predicting the change over time of the internal air temperature of the air conditioner using a mathematical model. Therefore, it is possible to diagnose the occurrence of steam leakage from the steam valve very easily without requiring a large work burden in advance.
As a result, abnormalities due to steam valve failure or deterioration can be diagnosed and checked at an early stage, so that proper air conditioning control can be performed while maintaining comfort without using wasted energy. .

It is a block diagram which shows the structure of a steam valve diagnostic apparatus. It is an example of a record of a driving history (driving state). It is an example of a record of an operation history (internal air temperature). It is a flowchart which shows a steam valve diagnostic process. It is explanatory drawing which shows the operation example of the steam valve diagnostic apparatus concerning 1st Embodiment. It is explanatory drawing which shows the operation example of the steam valve diagnostic apparatus concerning 2nd Embodiment. It is explanatory drawing which shows the example of a diagnosis of the steam valve diagnostic apparatus concerning 2nd Embodiment. It is explanatory drawing which shows the operation example of the steam valve diagnostic apparatus concerning 3rd Embodiment.

[Principle of the Invention]
First, the principle of the present invention will be described.
In a central air-conditioning system, when heating operation is performed with an air conditioner in winter, steam is supplied from a steam boiler to the heating coil of the air conditioner, and the air blown by heat exchange in the heating coil is heated to each section. It is supplied in the room. At this time, by adjusting the opening of a steam valve provided between the steam boiler and the heating coil, the flow rate of the steam supplied to the heating coil is adjusted, and the supply temperature of the air to be blown, that is, the room temperature Be controlled moderately.

  In such an air conditioning system, when the heating operation in the air conditioner is stopped, the steam valve provided between the steam boiler and the heating coil is fully closed, and the supply of steam from the steam boiler to the heating coil is stopped. . As a result, the internal air in the vicinity is not heated by the heating coil, and the internal air temperature gradually decreases from the time when the operation is stopped. After that, the steam valve is opened in response to the restart of operation, and the supply of steam from the steam boiler to the heating coil is restarted, so that the internal air temperature gradually rises after reaching the minimum temperature when restarting the operation. become.

  Here, when steam leaks from the steam valve that should be fully closed to the heating coil during the shutdown period from the shutdown of the air conditioner to the restart of the operation, the temperature of the heating coil becomes difficult to decrease, and the internal air in the vicinity of the heating coil The temperature is also difficult to decrease. For this reason, when there is no steam leakage at the steam valve, the degree of decrease in internal air temperature is large during the shutdown period, and when there is steam leakage at the steam valve, the degree of decrease in internal air temperature during the shutdown period. Becomes smaller.

  The present invention pays attention to the relationship between the presence or absence of steam leakage at the steam valve and the degree of decrease in the internal air temperature in the vicinity of the heating coil during the operation stop period of such an air conditioner, and the internal air temperature detected during the operation stop period. By comparing the degree of lowering with a normal range relating to the degree of lowering of a normal steam valve set in advance, the possibility of steam leakage at the steam valve is diagnosed.

Next, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
First, with reference to FIG. 1, the steam valve diagnostic apparatus 10 concerning the 1st Embodiment of this invention is demonstrated. FIG. 1 is a block diagram showing the configuration of the steam valve diagnostic apparatus.
The steam valve diagnosis device 10 is composed of an information processing device such as a personal computer, a server device, and an industrial controller as a whole, and based on the operation history collected and recorded from the air conditioner 20, the steam boiler 30 and the heating coil 24. It has a function of diagnosing the presence or absence of steam leakage at the steam valve 32 provided between the two.

The air conditioner 20 is a general air conditioner used in a central air conditioning system installed in a relatively large facility such as a tenant building, a shopping center, or a hospital, and is disposed in an air conditioner room of the facility. By distributing conditioned air to each section provided in the facility, it has a function of air conditioning the interior of each section.
The air conditioner 20 is provided with a filter 21, a refrigeration coil 22, a humidifier 23, a heating coil 24, an internal thermometer 25, and a blower fan 26 as main components.

  After the outside air taken in from the outside of the building and supplied to the air conditioner 20 through the outside air duct and the exhaust discharged from the room and returned to the air conditioner 20 through the return duct are cleaned by the filter 21, The temperature and humidity are adjusted by passing through the refrigeration coil 22, the humidifier 23, and the heating coil 24, and are supplied into the room by the blower fan 26 through the blower duct.

When the air conditioner 20 is heated in winter, the steam generated by the steam boiler 30 is supplied to the heating coil 24 through the steam pipe 31 and the steam valve 32, and heats the air by heat exchange in the heating coil 24. . As a result, the steam condenses into water, and is boosted by the booster pump 33 and returned to the steam boiler 30. At this time, the flow rate of the steam supplied to the heating coil 24 is adjusted by the opening degree of the steam valve 32 to control the temperature of the air.
Further, a part of the steam generated in the steam boiler 30 is supplied to the humidifier 23 via the steam pipe 31 and the humidifying valve 34 and is injected into the air flowing into the heating coil 24 to humidify the air.

On the other hand, when the air conditioner 20 is cooled in summer, the cold water generated by the refrigerator 35 is supplied to the refrigeration coil 22 via the chilled water pipe 36 and the chilled water valve 37, and air is exchanged by heat exchange in the refrigeration coil 22. Cooling. Thereby, the cold water becomes warm water and is returned to the refrigerator 35 by the water pump 38. At this time, the flow rate of the chilled water supplied to the refrigeration coil 22 is adjusted by the opening degree of the chilled water valve 37 to control the temperature of the air.
During the cooling operation, the operation of the steam boiler 30 and the booster pump 33 is basically stopped, and the steam valve 32 and the humidifier 23 are fully closed. Further, during the heating operation, the operation of the refrigerator 35 and the water pump 38 is basically stopped, and the cold water valve 37 is fully closed.

The internal thermometer 25 is disposed at, for example, an exhaust port through which air heated by the heating coil 24 is exhausted or an intake port through which this air is sucked into the blower fan 26, and the internal air of the internal air in the vicinity of the heating coil 24. It has a function of measuring the temperature T.
The air conditioner 20 has a function of periodically performing data communication with the steam valve diagnostic device 10. The internal air temperature T measured by the internal thermometer 25 and the start / stop of operation of the air conditioner 20 are sent to the steam valve diagnostic device 10. It has a function to notify.

[Steam valve diagnostic equipment]
Next, the configuration of the steam valve diagnostic device 10 according to the present embodiment will be described in detail with reference to FIG.
The steam valve diagnostic apparatus 10 is provided with an operation history recording unit 11, an operation history DB 12, an operation state detection unit 13, a normal range setting unit 14, and a steam valve diagnosis unit 15 as main functional units. Among these functional units, the operation history DB 12 includes a storage device such as a hard disk or a semiconductor memory, and the other functional units are realized by an arithmetic processing unit that executes a program on the CPU.

  The operation history recording unit 11 performs data communication with the air conditioner 20 so that the operation state indicating the operation start / stop of the air conditioner 20 and the heating coil 24 measured by the internal thermometer 25 of the air conditioner 20 are displayed. The internal air temperature T in the vicinity is periodically collected and recorded in the operation history DB 12. At this time, as an operation state indicating the operation start / operation stop of the air conditioner 20, for example, an operation state indicating the operation start / operation stop of the blower fan 26 may be collected.

  The period for collecting these operating states and the internal air temperature T depends on the heat capacity of the internal air, but is a period in which the internal air temperature T does not change significantly due to steam leakage from the steam valve 32, for example, at intervals of 1 minute. It is desirable to collect at the same time. In addition, as long as a big error does not arise between both, you may collect by a mutually different period and timing.

  The operation history DB 12 is a database that records the operation history collected by the operation history recording unit 11. FIG. 2 is a recording example of an operation history (operation state). Here, the operation state of the air conditioner 20, that is, the operation start / operation stop is recorded as a set at each operation state collection time. FIG. 3 is a recording example of the operation history (internal air temperature). Here, for each collection time of the internal air temperature T, the internal air temperature T measured by the internal thermometer 25 is recorded as a set.

  The operation status detection unit 13 has a function of specifying the operation stop period L from the operation history recorded in the operation history DB 12 until the air conditioner 203 stops the operation and then restarts, and the internal air temperature T during the operation stop period L. And a function of detecting the degree of decrease Δ.

  The normal range setting unit 14 has a function of setting, as a normal range, Δn as a normal range that can be taken by the steam valve 32 when the steam valve 32 is normal and there is no steam leakage.

  The steam valve diagnosis unit 15 obtains the normal range Δn from the normal range setting unit 14 and compares it with the degree of decrease Δ detected by the operating state detection unit 13, thereby determining whether or not steam leaks in the steam valve 32. Has a function to diagnose.

[Operation of First Embodiment]
Next, with reference to FIG. 4, operation | movement of the steam valve diagnostic apparatus 10 concerning this Embodiment is demonstrated. FIG. 4 is a flowchart showing the steam valve diagnosis process.
The steam valve diagnosis device 10 executes the steam valve diagnosis processing of FIG. 4 when diagnosing the steam valve 32. In the operation history DB 12, the operation history collected from the air conditioner 20 by the operation history recording unit 11 is recorded in advance, and the normal range Δn is set in the normal range setting unit 14 in advance. To do.

First, the operation state detection unit 13 specifies an operation stop period L from the operation history recorded in the operation history DB 12 until the air conditioner 203 stops operating and then restarts (step 100). A decrease degree Δ of the internal air temperature T is detected (step 101).
Next, the steam valve diagnosis unit 15 obtains the normal range Δn from the normal range setting unit 14 (step 102), and compares it with the decrease degree Δ detected by the operating state detection unit 13 (step 103).

Here, when the degree of decrease Δ is not included in the normal range Δn (step 103: NO), the steam valve diagnosis unit 15 diagnoses the possibility of steam leakage in the steam valve 32 (step 104), and a series of steams The valve diagnosis process is terminated.
On the other hand, when the decrease degree Δ is included in the normal range Δn (step 103: YES), the steam valve diagnosis unit 15 diagnoses that there is no possibility of steam leakage in the steam valve 32 (step 105), and a series of steam valve diagnosis. The process ends.

[Operation Example of First Embodiment]
Next, with reference to FIG. 5, the operation example of the steam valve diagnostic apparatus 10 concerning this Embodiment is demonstrated. FIG. 5 is an explanatory diagram illustrating an operation example of the steam valve diagnostic apparatus according to the first embodiment. Here, a graph showing a time-series change of the internal air temperature T in the case of using a normal steam valve A without steam leakage and a steam valve B with steam leakage is shown, and the horizontal axis represents time t. The vertical axis indicates the internal air temperature T.

  In the present embodiment, the degree of decrease Δ is composed of the temperature drop of the internal air temperature T during the operation stop period L, and the internal air temperature T0 at the time t0 when the air conditioner 20 is stopped and the internal air temperature T1 when the operation is resumed t1. The case where it calculates | requires by the difference with these, ie, the fall temperature range T1-T0, is demonstrated as an example. For this reason, as the normal range Δn, a range that can be taken by the temperature drop range when the steam valve is normal without steam leakage is set.

  In addition, when the operation stop period L varies and the temperature drop range changes according to the time length of the operation stop period L, the normal range set in the normal range setting unit 14 in advance for each assumed time length. The steam valve diagnosis unit 15 may select the normal range Δn corresponding to the actual time length t1 to t0 of the operation stop period L from Δn. Alternatively, the normal range Δn corresponding to the actual time length t1 to t0 of the operation stop period L is obtained from the function expression indicating the relationship between the time length set in the normal range setting unit 14 and the normal range Δn. The diagnosis unit 15 may calculate.

  First, in the case of the steam valve A, as shown by the solid line graph in FIG. 5, the internal air temperature T is changed from the internal air temperature T0 at the time of operation stop to the internal air at the time of operation resumption t1 in the operation stop period L. The temperature has decreased to T1a. For this reason, the decrease degree Δa of the steam valve A is obtained by the difference between the internal air temperatures T, that is, the decrease temperature width T1a-T0. Here, since the degree of decrease Δa is included in the normal range Δn, it is diagnosed that there is no possibility of steam leakage in the steam valve A.

  On the other hand, in the case of the steam valve B, the internal air temperature T is changed from the internal air temperature T0 at the operation stop time t0 to the internal air at the operation restart time t1 in the operation stop period L as shown by the broken line graph of FIG. The temperature has decreased to T1b. For this reason, the degree of decrease Δb of the steam valve B is obtained by the difference in internal air temperature, that is, the decrease temperature width T1b−T0. Here, since the degree of decrease Δb is not included in the normal range Δn, it is diagnosed that steam leakage in the steam valve B is possible.

  At this time, as a method for determining whether or not the decrease degrees Δa and Δb are included in the normal range Δn, the determination threshold value Δth indicating the boundary value of the normal range Δn is compared with the decrease degrees Δa and Δb. Also good. In this case, since Δa ≧ Δth, steam leakage in the steam valve A is diagnosed as not possible. On the other hand, since Δb <Δth, steam leakage in the steam valve B is diagnosed as possible.

[Effect of the first embodiment]
As described above, according to the present embodiment, the internal air temperature in the operation stop period L from the operation history recorded in the operation history DB 12 until the air conditioner 20 stops the operation until the air conditioner 20 restarts the operation is detected. The decrease degree Δ of T is detected, and the steam valve diagnosis unit 15 compares the decrease degree Δ with the normal range Δn, thereby diagnosing the possibility of steam leakage in the steam valve 32. .

Thereby, when there is no steam leakage from the steam valve 32, the steam valve 32 is fully closed during the operation stop period L, and the internal air is not heated by the heating coil, so that the degree of decrease Δ of the internal air temperature T is normal. It is included in the range Δn, and it is diagnosed that there is no possibility of steam leakage in the steam valve 32.
On the other hand, when there is a steam leak from the steam valve 32, a part of the steam is supplied from the steam valve 32 to the heating coil even during the operation stop period L, and the internal air is slightly heated. The degree Δ is not included in the normal range Δn, and it is diagnosed that there is a possibility of steam leakage in the steam valve 32.

Therefore, according to the present embodiment, the time constant of the internal air temperature of the air conditioner, etc. is obtained by repeating the experiment in advance, as in the case of predicting the change with time of the internal air temperature of the air conditioner using the mathematical model. Therefore, it is possible to diagnose the occurrence of steam leakage from the steam valve very easily without requiring a large work burden in advance.
As a result, abnormalities due to steam valve failure or deterioration can be diagnosed and checked at an early stage, so that proper air conditioning control can be performed while maintaining comfort without using wasted energy. .

  Further, in the present embodiment, the operation state detection unit 13 detects the decrease temperature range T1-T0 of the internal air temperature T in the operation stop period L as the decrease degree Δ, and the normal range setting unit 14 sets the normal range Δn. When a normal temperature drop range related to the temperature drop range T1-T0 in the operation stop period L is set and the steam valve diagnosis unit 15 does not include the detected temperature drop range T1-T0 in the normal temperature drop range Δth. May be diagnosed as the possibility of steam leakage in the steam valve.

  Thereby, the possibility of steam leakage in the steam valve can be diagnosed based on the temperature drop range for the entire period from the start to the end of the operation stop period L. For this reason, the influence of the temporary air temperature change in the operation stop period L can be eliminated, and a stable diagnosis can be realized.

Further, in the present embodiment, not a reduced temperature range for the entire period from the start to the end of the operation stop period L, but a part of the target period provided in the operation stop period L, for example, several hours from the operation stop The possibility of steam leakage in the steam valve may be diagnosed on the basis of the temperature drop in the target period with the later as the start time and the end time as 1 hour later.
This makes it possible to select a period of the operation stop period L that is less affected by a temporary air temperature change and realize a stable diagnosis.

Further, in the present embodiment, the driving state detection unit 13 uses the unit time for the decrease temperature range in the entire period from the start to the end of the operation stop period L or in a part of the target period provided in the operation stop period L. For example, the possibility of steam leakage in the steam valve may be diagnosed by normalizing to a reduced temperature range per hour and comparing this with the normal range Δn.
As a result, it is possible to deal with changes in the operation stop period L simply by setting the normal range Δn per unit time. Therefore, the normal range Δn can be unified, and the work load related to the setting of the normal range Δn can be reduced. .

[Second Embodiment]
Next, the steam valve diagnostic apparatus 10 according to the second embodiment of the present invention will be described.
In 1st Embodiment, the case where the fall temperature width T1-T0 of the internal air temperature T in the operation stop period L was used as the fall degree (DELTA) was demonstrated as an example. In the present embodiment, a case will be described in which the rate of decrease of internal air temperature T is used as the degree of decrease Δ instead of the range of decrease in internal air temperature T.

That is, in the present embodiment, the operating state detection unit 13 has a function of detecting the rate of decrease of the internal air temperature T as the decrease degree Δ.
The normal range setting unit 14 has a function of setting a normal decrease rate range related to the decrease rate as the normal range Δn.
The steam valve diagnosis unit 15 has a function of diagnosing the possibility of steam leakage in the steam valve when the detected rate of decrease is not included in the normal rate of decrease range.
Other configurations and operations relating to the steam valve diagnostic apparatus 10 according to the present embodiment are the same as those in the first embodiment, and a detailed description thereof is omitted here.

[Operation Example of Second Embodiment]
Next, with reference to FIG. 6, the operation example of the steam valve diagnostic apparatus 10 concerning this Embodiment is demonstrated. FIG. 6 is an explanatory diagram illustrating an operation example of the steam valve diagnostic apparatus according to the second embodiment. Here, a graph showing a time-series change of the internal air temperature T in the case of using a normal steam valve A without steam leakage and a steam valve B with steam leakage is shown, and the horizontal axis represents time t. The vertical axis indicates the internal air temperature T.

  In the present embodiment, the degree of decrease Δ is the rate of decrease of the internal air temperature T during the operation stop period L, and the internal air temperature T0 at the time t0 when the air conditioner 20 is stopped and the internal air temperature T1 at the time t1 when the operation is resumed. An example will be described in which the difference between the two, that is, the decrease temperature range T1-T0 is obtained by dividing by the actual time length t1-t0 of the operation stop period L. For this reason, as the normal range Δn, a range in which the reduction rate can be taken when the steam valve is normal without steam leakage is set.

  First, in the case of the steam valve A, as shown by the solid line graph in FIG. 6, the internal air temperature T is changed from the internal air temperature T0 at the time of operation stop to the internal air at the time of operation resumption t1 in the operation stop period L. The temperature has decreased to T1a. Therefore, the degree of decrease Δa of the steam valve A is obtained by dividing the difference between the internal air temperatures T, that is, the decreased temperature range T1a-T0, by the actual time length t1-t0 of the operation stop period L.

  On the other hand, in the case of the steam valve B, the internal air temperature T is changed from the internal air temperature T0 at the time of operation stop to the internal air at the time of operation resumption t1 in the operation stop period L as shown by the broken line graph of FIG. The temperature has decreased to T1b. For this reason, the decrease degree Δb of the steam valve B is obtained by dividing the difference in internal air temperature, that is, the decrease temperature width T1b-T0 by the actual time length t1-t0 of the operation stop period L.

  FIG. 7 is an explanatory diagram illustrating a diagnosis example of the steam valve diagnostic apparatus according to the second embodiment. Here, the relationship between the rate of decrease of the internal air temperature T and the normal range Δn when using a normal steam valve A without steam leakage and a steam valve B with steam leakage is shown, and the horizontal axis is The steam valve X is shown, and the vertical axis shows the reduction rate Δx.

  As shown in FIG. 7, the rate of decrease Δa, which is the degree of decrease of the steam valve A, is included in the normal range Δn, and therefore it is diagnosed that steam leakage in the steam valve A is not possible. On the other hand, since the rate of decrease Δb, which is the degree of decrease in the steam valve B, is not included in the normal range Δn, it is diagnosed that steam leakage in the steam valve B is possible.

  At this time, as a method for determining whether or not the decrease degrees Δa and Δb are included in the normal range Δn, the determination threshold value Δth indicating the boundary value of the normal range Δn is compared with the decrease degrees Δa and Δb. Also good. In this case, since Δa ≧ Δth, steam leakage in the steam valve A is diagnosed as not possible. On the other hand, since Δb <Δth, steam leakage in the steam valve B is diagnosed as possible.

[Effect of the second embodiment]
As described above, in the present embodiment, the operating state detection unit 13 detects the rate of decrease of the internal air temperature T as the decrease degree Δ, and the normal range setting unit 14 sets the normal decrease rate range related to the decrease rate as the normal range Δn. The steam valve diagnosis unit 15 is configured to diagnose that there is a possibility of steam leakage in the steam valve when the detected decrease rate is not included in the normal decrease rate range.
Thereby, since it is possible to cope with the change in the operation stop period L only by setting the normal range Δn related to the rate of decrease of the internal air temperature T, the normal range Δn can be unified, and work related to the setting of the normal range Δn The burden can be reduced.

In the present embodiment, it is not a reduction rate for the entire period from the start to the end of the operation stop period L, but a part of the target period provided within the operation stop period L, for example, several hours after the operation stop May be diagnosed as to whether or not there is a possibility of steam leakage in the steam valve, based on the rate of decrease in the target period starting after 1 hour.
This makes it possible to select a period of the operation stop period L that is less affected by a temporary air temperature change and realize a stable diagnosis.

[Third Embodiment]
Next, a steam valve diagnostic apparatus 10 according to a third embodiment of the present invention will be described.
In 1st Embodiment, the case where the fall temperature width T1-T0 of the internal air temperature T in the operation stop period L was used as the fall degree (DELTA) was demonstrated as an example. In the present embodiment, a case will be described in which the internal air temperature T1 itself at the time of resuming operation is used as the degree of decrease Δ, instead of the temperature range of the internal air temperature T.

That is, in the present embodiment, the operating state detection unit 13 has a function of detecting the internal air temperature T1 when the operation of the air conditioner 20 is resumed as the degree of decrease Δ.
The normal range setting unit 14 has a function of setting a normal internal air temperature range related to the internal air temperature T1 as the normal range Δn.
The steam valve diagnosis unit 15 has a function of diagnosing the possibility of steam leakage in the steam valve when the detected internal air temperature T1 is not included in the normal internal air temperature range.
Other configurations and operations relating to the steam valve diagnostic apparatus 10 according to the present embodiment are the same as those in the first embodiment, and a detailed description thereof is omitted here.

[Operation Example of Third Embodiment]
Next, with reference to FIG. 8, the operation example of the steam valve diagnostic apparatus 10 concerning this Embodiment is demonstrated. FIG. 8 is an explanatory diagram illustrating an operation example of the steam valve diagnostic apparatus according to the third embodiment. Here, a graph showing a time-series change of the internal air temperature T in the case of using a normal steam valve A without steam leakage and a steam valve B with steam leakage is shown, and the horizontal axis represents time t. The vertical axis indicates the internal air temperature T.

  In the present embodiment, a case where the degree of decrease Δ is composed of the internal air temperature T1 when the operation of the air conditioner 20 is resumed will be described as an example. For this reason, as the normal range Δn, a range that the internal air temperature T1 can take when the steam valve is normal without steam leakage is set.

  When the operation stop period L fluctuates and the internal air temperature T1 changes according to the time length of the operation stop period L, the normal range set in the normal range setting unit 14 in advance for each assumed time length. The steam valve diagnostic unit 15 may select the normal range Δn corresponding to the actual time length t1 to t0 of the operation stop period L from the range Δn. Alternatively, the normal range Δn corresponding to the actual time length t1 to t0 of the operation stop period L is obtained from the function expression indicating the relationship between the time length set in the normal range setting unit 14 and the normal range Δn. The diagnosis unit 15 may calculate.

  First, in the case of the steam valve A, as shown by the solid line graph in FIG. 8, the internal air temperature T is changed from the internal air temperature T0 at the time of operation stop to the internal air at the time of operation resumption t1 in the operation stop period L. The temperature has decreased to T1a. Therefore, the degree of decrease Δa of the steam valve A becomes the internal air temperature T1a. Here, since the degree of decrease Δa is included in the normal range Δn, it is diagnosed that there is no possibility of steam leakage in the steam valve A.

  On the other hand, in the case of the steam valve B, the internal air temperature T is changed from the internal air temperature T0 at the time of the operation stop to the internal air at the time of the operation resumption t1 in the operation stop period L as shown by the broken line graph of FIG. The temperature has decreased to T1b. For this reason, the degree of decrease Δb of the steam valve B becomes the internal air temperature T1b. Here, since the degree of decrease Δb is not included in the normal range Δn, it is diagnosed that steam leakage in the steam valve B is possible.

  At this time, as a method for determining whether or not the decrease degrees Δa and Δb are included in the normal range Δn, the determination threshold value Δth indicating the boundary value of the normal range Δn is compared with the decrease degrees Δa and Δb. Also good. In this case, since Δa ≦ Δth, steam leakage in the steam valve A is diagnosed as not possible. On the other hand, since Δb> Δth, steam leakage in the steam valve B is diagnosed as possible.

[Effect of the third embodiment]
As described above, in the present embodiment, the operation state detection unit 13 detects the internal air temperature T1 when the air conditioner 20 resumes operation as the decrease degree Δ, and the normal range setting unit 14 sets the internal air temperature as the normal range Δn. A normal internal air temperature range related to T1 is set, and the steam valve diagnosis unit 15 diagnoses that there is a possibility of steam leakage in the steam valve when the detected internal air temperature T1 is not included in the normal internal air temperature range. It is what you do.

Thereby, the diagnosis of the steam valve eliminates the need for the internal air temperature T0 when the air conditioner 20 is stopped, and only the internal air temperature T1 when the operation is resumed. Can be reduced.
Further, since the normal range Δn related to the internal air temperature T1 can be set only to cope with the change in the operation stop period L, the normal range Δn can be unified, and the work load related to the setting of the normal range Δn can be reduced. .

Further, in the present embodiment, the steam in the steam valve is not based on the internal air temperature T1 at the time of restarting operation but on the target time provided within the operation stop period L, for example, at the time after several hours from the operation stop. You may make it diagnose the possibility of a leak.
This makes it possible to select a period of the operation stop period L that is less affected by a temporary air temperature change and realize a stable diagnosis.

[Extended embodiment]
The present invention has been described above with reference to the embodiments, but the present invention is not limited to the above embodiments. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention. In addition, each embodiment can be implemented in any combination within a consistent range.

  DESCRIPTION OF SYMBOLS 10 ... Steam valve diagnostic apparatus, 11 ... Operation history recording part, 12 ... Operation history DB, 13 ... Operation condition detection part, 14 ... Normal range setting part, 15 ... Steam valve diagnosis part, 20 ... Air conditioner, 21 ... Filter, DESCRIPTION OF SYMBOLS 22 ... Refrigeration coil, 23 ... Humidifier, 24 ... Heating coil 24 ... Internal thermometer 25 ... Blower fan, 30 ... Steam boiler, 31 ... Steam pipe, 32 ... Steam valve, 33 ... Booster pump, 34 ... Humidification valve, 35 ... refrigerator, 36 ... cold water pipe, 37 ... cold water valve, 38 ... water pump, L ... operation stop period, T, T0, T1, T1a, T1b ... internal air temperature, Δ, Δa, Δb ... degree of decrease, Δn ... Normal range, Δth... Judgment threshold.

Claims (6)

A steam valve diagnostic device for diagnosing steam leakage in a steam valve that adjusts the flow rate of steam supplied from a steam boiler to a heating coil of an air conditioner,
An operation history recording unit that periodically collects the start and stop of operation of the air conditioner and the internal air temperature in the vicinity of the heating coil and records the operation history of the air conditioner;
From the recorded operation history, an operation status detection unit that detects the degree of decrease in the internal air temperature in the operation stop period from when the air conditioner stops operation until it restarts,
A normal range setting unit that sets a range that the degree of decrease can take as a normal range when there is no steam leakage in the steam valve;
A steam valve diagnosis device comprising: a steam valve diagnosis unit that diagnoses the possibility of steam leakage in the steam valve by comparing the detected degree of decrease with the normal range. In the steam valve diagnostic apparatus according to claim 1,
The operation state detection unit detects a decrease temperature width of the internal air temperature in the operation stop period as the decrease degree,
The normal range setting unit sets a normal decrease temperature range related to the decrease temperature range in the operation stop period as the normal range,
The steam valve diagnosis unit diagnoses that there is a possibility of steam leakage in the steam valve when the detected temperature drop is not included in the normal temperature drop range. apparatus. In the steam valve diagnostic apparatus according to claim 1,
The operating state detection unit detects a decrease temperature width of the internal air temperature per unit time as the decrease degree,
The normal range setting unit sets a normal decrease temperature range related to the decrease temperature range per unit time as the normal range,
The steam valve diagnosis unit diagnoses that there is a possibility of steam leakage in the steam valve when the detected temperature drop is not included in the normal temperature drop range. apparatus. In the steam valve diagnostic apparatus according to claim 1,
The operating state detection unit detects the rate of decrease in the internal air temperature as the degree of decrease,
The normal range setting unit sets a normal decrease rate range related to the decrease rate as the normal range,
The steam valve diagnosis unit diagnoses that there is a possibility of steam leakage in the steam valve when the detected decrease rate is not included in the normal decrease rate range. In the steam valve diagnostic apparatus according to claim 1,
The operating state detection unit detects the internal air temperature when the air conditioner resumes operation as the degree of decrease,
The normal range setting unit sets a normal internal air temperature range related to the internal air temperature when the operation is resumed,
The steam valve diagnosis unit diagnoses that there is a possibility of steam leakage in the steam valve when the detected internal air temperature is not included in the normal internal air temperature range. apparatus. A steam valve diagnostic method for diagnosing steam leakage in a steam valve that adjusts the flow rate of steam supplied from a steam boiler to a heating coil of an air conditioner,
An operation history recording step of periodically collecting the operation start and operation stop of the air conditioner and the internal air temperature in the vicinity of the heating coil and recording it as the operation history of the air conditioner;
From the recorded operation history, an operation state detection step of detecting the degree of decrease in the internal air temperature in the operation stop period from when the air conditioner stops operation until it restarts,
A normal range setting step of setting a range that the degree of decrease can take as a normal range when there is no steam leakage in the steam valve;
A steam valve diagnosis method comprising: a steam valve diagnosis step of diagnosing the possibility of steam leakage in the steam valve by comparing the detected degree of decrease with the normal range.

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