Calorific value derivation system

Abstract

This calorific value derivation system is provided with: gas supply facility having a first transmission control unit for transmitting gas component information to a center server; the center server having an information calculation unit that calculates, on the basis of the gas component information, gas heat quantity relationship information indicating the relationship between a gas characteristic and a calorific value, and newly calculates the gas heat quantity relationship information in accordance with the fluctuation of the gas component information, and a second transmission control unit that transmits the gas heat quantity relationship information to a gas meter; and the gas meter having a flow rate measurement unit that measures the flow rate of a gas on the basis of the gas characteristic, a calorific coefficient calculation unit that calculates a calorific coefficient on the basis of the gas heat quantity relationship information, a calorific value acquisition unit that acquires an instantaneous calorific value on the basis of the gas flow rate and the calorific coefficient, and integrates the instantaneous calorific value for each prescribed time to acquire the calorific value of the gas, and a third transmission control unit that transmits the flow rate and the calorific value to the center server.

Description

Heat generation calculation system

[0001] The present disclosure relates to a calorific value derivation system that derives the calorific value of gas in a gas meter.

[0002] Conventionally, a calorific value derivation device is known for a gas meter, which derives the attenuation rate of ultrasonic waves, derives the components of the gas flowing through the gas flow path based on the derived attenuation rate, and derives the calorific value of the gas based on the components (Patent Document 1).

[0003] Patent No. 6586351

[0004] However, this requires the addition of functions not normally available, namely the ability to measure the ultrasonic attenuation rate and the ability to derive gas composition, which increases the cost of the gas meter and the power consumption of the gas meter.Furthermore, because the gas composition varies depending on the time of day, it is necessary to derive the calorific value of the gas with high accuracy.

[0005] Therefore, an object of the present disclosure is to provide a heat generation amount derivation system that can derive the heat generation amount with high accuracy while suppressing costs.

[0006] A calorific value derivation system according to the present disclosure is a calorific value derivation system including a gas supply facility, a center server, and a gas meter, and including a first communication unit that is provided within the gas supply facility or separately from the gas supply facility and communicates with the outside, a second communication unit that is built into the center server or provided separately from the center server and communicates with the outside, and a third communication unit that is built into the gas meter or provided separately from the gas meter and communicates with the outside, wherein the gas supply facility has a first transmission control unit that controls transmission of component information of a gas to be supplied to the center server via the first communication unit, and the center server derives a gas calorific value that indicates a relationship between characteristics of the gas and a calorific value based on the component information of the gas acquired via the second communication unit. The gas meter has an information calculation unit that calculates relationship information and newly calculates the gas calorific value relationship information in accordance with fluctuations in the component information of the gas, and a second transmission control unit that controls the transmission of the gas calorific value relationship information to the gas meter via the second communication unit, and the gas meter has a flow measurement unit that measures the flow rate of the gas based on the characteristics of the gas, a calorific value calculation unit that calculates a calorific value based on the gas calorific value relationship information acquired via the third communication unit, a calorific value acquisition unit that acquires an instantaneous calorific value based on the gas flow rate and the calorific value and accumulates the instantaneous calorific value every predetermined time to acquire the calorific value of the gas, and a third transmission control unit that controls the transmission of the flow rate and the calorific value to the center server via the third communication unit.

[0007] According to the present disclosure, a gas supply facility transmits gas component information to a center server. An information calculation unit of the center server calculates gas calorific value relationship information based on the gas component information. The information calculation unit updates the gas calorific value relationship information in response to fluctuations in the gas component information. A calorific value coefficient calculation unit of the gas meter then calculates a calorific value based on the gas calorific value relationship information. A calorific value acquisition unit of the gas meter acquires instantaneous calorific values, and a calorific value is obtained by integrating the instantaneous calorific values. Because the gas calorific value relationship information calculated based on the gas component information transmitted from the gas supply facility is transmitted from the center server to the gas meter, there is no need to add a gas component derivation function to the gas meter, as in the past. This reduces or prevents increases in gas meter costs and power consumption. Furthermore, because the center server updates the gas calorific value relationship information in response to fluctuations in the gas component information and transmits it to the gas meter, the calorific value of the gas can be accurately derived even if the gas components vary depending on the time period. As a result, it is possible to accurately derive the calorific value while reducing costs.

[0008] In the above disclosure, the gas meters may include a first gas meter provided in a first supply path, a second gas meter provided in the first supply path downstream of the first gas meter, and a third gas meter provided in a second supply path branching off from a portion of the first supply path downstream of the first gas meter, and the center server may further have an allocation acquisition unit that acquires one of the heat values ​​obtained by apportioning the heat value received from the first gas meter based on the ratio between the integrated value of the flow rate received from the second gas meter and the integrated value of the flow rate received from the third gas meter as the heat value of the second gas meter, and acquires the other heat value as the heat value of the third gas meter.

[0009] According to the above configuration, in a configuration in which a first gas meter and multiple gas meters (a second gas meter and a third gas meter) are provided downstream of the first gas meter, the calorific value of each of the second gas meter and the third gas meter can be obtained simply by obtaining the calorific value of the first gas meter. This eliminates the need to calculate the calorific values ​​of the second gas meter and the third gas meter individually, thereby reducing costs.

[0010] In the above disclosure, the gas supply facility may include a first gas supply facility and a second gas supply facility as a plurality of gas supply facilities that supply gas to one of the gas meter, and the center server may further include an information acquisition unit that acquires information related to characteristics of the gas as first information based on component information of the gas supplied by the first gas supply facility and acquires information related to characteristics of the gas as second information based on component information of the gas supplied by the second gas supply facility, and a determination unit that receives the information related to characteristics of the gas supplied to the gas meter as reference information via the second communication unit and determines from which of the first gas supply facility and the second gas supply facility the gas supplied to the gas meter is being supplied based on a comparison between the reference information and the first information and a comparison between the reference information and the second information, and the second transmission control unit may transmit to the gas meter either the gas calorific value relationship information related to the gas supplied by the first gas supply facility or the gas calorific value relationship information related to the gas supplied by the second gas supply facility depending on a determination result by the determination unit.

[0011] According to the above configuration, the determination unit determines whether the gas being supplied to the gas meter is supplied from the first gas supply facility or the second gas supply facility based on a comparison between the reference information and the first information and a comparison between the reference information and the second information. Then, the second transmission control unit transmits to the gas meter either the gas calorific value relationship information related to the gas being supplied from the first gas supply facility or the gas calorific value relationship information related to the gas being supplied from the second gas supply facility, depending on the determination result by the determination unit. This allows the gas meter to obtain the gas calorific value relationship information corresponding to the gas being currently supplied, thereby enabling the calorific value to be calculated with high accuracy.

[0012] According to the present disclosure, it is possible to provide a heat generation amount derivation system that can derive a heat generation amount with high accuracy while suppressing costs.

[0013] 7 is a block diagram showing the configuration of a calorific value derivation system according to an embodiment; FIG. 8 is an explanatory diagram showing an example of gas component information; FIG. 9 is an explanatory diagram showing an example of gas calorific value relationship information; FIG. 10 is a flowchart showing the processing flow by the calorific value derivation system of FIG. 1; FIG. 11 is a block diagram showing the configuration of a calorific value derivation system according to an embodiment; FIG. 12 is a flowchart showing the processing flow by the calorific value derivation system of FIG. 5; FIG. 13 is a block diagram showing the configuration of a calorific value derivation system according to an embodiment; FIG. 14 is an explanatory diagram showing an example of first information, FIG. 15 is an explanatory diagram showing an example of second information, and FIG. 16 is an explanatory diagram showing an example of basic information; and FIG. 17 is a flowchart showing the processing flow by the calorific value derivation system of FIG.

[0014] A heat generation amount deriving system according to an embodiment of the present disclosure will be described below with reference to the drawings. The heat generation amount deriving system described below is merely one embodiment of the present disclosure. Therefore, the present disclosure is not limited to the following embodiment, and additions, deletions, and modifications are possible within the scope of the present disclosure.

[0015] (First Embodiment) Fig. 1 is a block diagram showing a calorific value derivation system 100 according to this embodiment. As shown in Fig. 1, the calorific value derivation system 100 includes a gas supply facility 10, a center server 20, and a gas meter 30. The gas meter 30 can be provided for each consumer's home. Note that, although Fig. 1 illustrates one gas meter 30 and one gas supply facility 10, the calorific value derivation system 100 may include two or more gas meters 30 and two or more gas supply facilities 10.

[0016] Gas supply facility 10 has a first transmission unit 11 corresponding to a first transmission control unit, a first communication unit 12, and a component measurement unit 13. Center server 20 has a second communication unit 21, an information calculation unit 22, a second transmission unit 23 corresponding to the second transmission control unit, and a memory unit 24. Gas meter 30 has, for example, an ultrasonic flowmeter side unit 31, a third communication unit 32, a calorific coefficient calculation unit 33, a calorific value acquisition unit 34, a third transmission unit 35 corresponding to the third transmission control unit, and a memory unit 36. Gas supplied from gas supply facility 10 flows to flowmeter side unit 31 of gas meter 30 via first supply path 50. The first transmission unit 11 of the gas supply facility 10, the information calculation unit 22 and the second transmission unit 23 of the center server 20, and the heat coefficient calculation unit 33, the heat value acquisition unit 34, and the third transmission unit 35 of the gas meter 30 are functionally realized by a microcontroller including a CPU (Central Processing Unit) and memory (ROM (Read Only Memory) and RAM (Random Access Memory)) storing a program, or an ASIC (Application Specific Integrated Circuit), etc. The same applies to the apportionment acquisition unit 25, the information acquisition unit 26, and the determination unit 27 described below. The storage unit 24 and the storage unit 36 ​​can be realized by various types of memory or a hard disk, etc.

[0017] Each component will be described below. The first communication unit 12 of the gas supply facility 10 communicates with the outside. Specifically, the first communication unit 12 communicates wirelessly with the second communication unit 21 of the center server 20. As a wireless communication method between the first communication unit 12 and the second communication unit 21, for example, a communication network such as the Internet, LAN, LPWA (Low Power Wide Area), or WI-SUN can be used. The wireless communication method between the second communication unit 21 and the third communication unit 32 of the gas meter 30 is also the same as above.

[0018] The component measurement unit 13 measures the components of the gas supplied to the gas meter 30. The component measurement unit 13 measures the gas components periodically. For example, the component measurement unit 13 measures the gas components every hour. The component measurement unit 13 acquires gas component information I1 as shown in FIG. 2. The gas component information I1, as shown in FIG. 2, represents the proportion of each of the multiple components contained in the gas to the total, expressed as a volume percentage. The gas component information I1 in FIG. 2 includes component information at 12:00 and 13:00. Note that the gas component information I1 may also include component information at an irregular time.

[0019] The first transmission unit 11 controls transmission of the gas component information I1 to the center server 20 via the first communication unit 12. In this case, the first transmission unit 11 periodically transmits the gas component information I1 to the center server 20. For example, the first transmission unit 11 transmits the gas component information I1 to the center server 20 every hour.

[0020] The second communication unit 21 of the center server 20 communicates wirelessly with the first communication unit 12 of the gas supply facility 10. The information calculation unit 22 calculates gas calorific value relationship information I2 ( FIG. 3 ) indicating the relationship between the characteristics of the gas and the calorific value based on the gas component information I1 acquired via the second communication unit 21. As shown in FIG. 3 , the gas calorific value relationship information I2 indicates that the calorific value tends to increase as the propagation time increases. Using a known method, the information calculation unit 22 calculates the ultrasonic propagation time, which is information related to the gas characteristics, when the temperature is 0° C. and the pressure is 1 atm, based on the gas molecular information derived from the gas component information I1, and calculates the gas calorific value relationship information I2 indicating the relationship between the calculated propagation time and the calorific value of the gas. Furthermore, the information calculation unit 22 newly calculates the gas calorific value relationship information I2 in response to fluctuations in the gas component information I1. That is, the information calculation unit 22 updates the gas calorific value relationship information I2. In this case, the gas calorific value relationship information I2 may be updated when, for example, a ±1% variation in volume occurs in at least one component among the multiple components in the gas component information I1 in Fig. 2. Alternatively, the gas calorific value relationship information I2 may be updated when a ±1% variation occurs in the propagation time.

[0021] The second transmission unit 23 controls transmission of the gas calorific value relationship information I2 to the gas meter 30 via the second communication unit 21. The storage unit 24 stores the gas component information I1, the gas calorific value relationship information I2, the integrated value of the gas flow rate in the gas meter 30, the integrated value of the gas calorific value in the gas meter 30, etc.

[0022] The third communication unit 32 of the gas meter 30 performs wireless communication with the second communication unit 21 of the center server 20. Note that the third communication unit 32 of the gas meter 30 may perform wired communication with the second communication unit 21 of the center server 20.

[0023] The flow meter unit 31 measures the flow rate of the gas based on the characteristics of the gas. Specifically, the flow meter unit 31 is an ultrasonic flow meter unit that calculates the flow velocity of the gas based on the propagation time of ultrasonic waves. The flow meter unit 31 calculates the flow rate of the gas based on the flow velocity of the gas using a known calculation formula.

[0024] The calorific value coefficient calculation unit 33 calculates the calorific value coefficient based on the gas calorific value relationship information I2 acquired via the third communication unit 32. In this regard, the calorific value of the gas is expressed as the calorific value (1 m ３ The calorific value is obtained by multiplying the energy per unit volume (also called the calorific value coefficient) by the gas flow rate (volume). The calorific value calculation unit 33 obtains the calorific value from the propagation time based on the gas calorific value relationship information I2 sent from the center server 20, and calculates the calorific value from the calorific value and the flow rate.

[0025] The calorific value acquisition unit 34 acquires the calorific value for each predetermined time period as the instantaneous calorific value based on the gas flow rate (instantaneous flow rate) and the calorific coefficient. Specifically, the calorific value acquisition unit 34 acquires the instantaneous calorific value by multiplying the instantaneous gas flow rate and the calorific coefficient. The calorific value acquisition unit 34 may acquire the instantaneous calorific value from a table showing the relationship between the instantaneous flow rate and the calorific coefficient, which is stored in advance in the storage unit 36. The calorific value acquisition unit 34 also acquires the calorific value of the gas as an integrated value by integrating the instantaneous calorific value for each predetermined time period.

[0026] The third transmission unit 35 controls transmission of the flow rate and calorific value acquired as described above to the center server 20 via the third communication unit 32. The memory unit 36 ​​stores the instantaneous flow rate of the gas, the calorific coefficient, the instantaneous calorific value, the integrated value of the calorific value, and the like.

[0027] 4 is a flowchart showing the flow of processing by the calorific value derivation system 100. As shown in FIG. 4, the component measurement unit 13 of the gas supply facility 10 measures the gas components and obtains gas component information I1 (step S1). Next, the first transmission unit 11 transmits the gas component information I1 to the center server 20 (step S2).

[0028] Next, the information calculation unit 22 of the center server 20 calculates the gas calorie relationship information I2 based on the acquired gas component information I1 (step S3), and the second transmission unit 23 transmits the gas calorie relationship information I2 to the gas meter 30 (step S4).

[0029] The flow meter unit 31 of the gas meter 30 measures the gas flow rate (step S5). Next, the calorific value acquisition unit 34 acquires the calorific value per predetermined time as the instantaneous calorific value based on the gas flow rate (instantaneous flow rate) and the calorific value coefficient, and acquires the integrated value of the calorific value by integrating the instantaneous calorific value per predetermined time (step S6).

[0030] Next, the third transmission unit 35 transmits the acquired flow rate and calorific value to the center server 20 (step S7). Then, the storage unit 24 of the center server 20 stores the integrated value of the gas flow rate and the integrated value of the gas calorific value in the gas meter 30 for each gas meter 30 (step S8).

[0031] As described above, according to the calorific value derivation system 100 of this embodiment, the gas supply facility 10 transmits the gas component information I1 to the center server 20. The information calculation unit 22 of the center server 20 calculates the gas calorific value relationship information I2 based on the gas component information I1. The information calculation unit 22 also updates the gas calorific value relationship information I2 in response to fluctuations in the gas component information I1. The calorific value coefficient calculation unit 33 of the gas meter 30 then calculates the calorific value based on the gas calorific value relationship information I2. The calorific value acquisition unit 34 then acquires the instantaneous calorific values, and then acquires the calorific value obtained by integrating the instantaneous calorific values. Because the gas calorific value relationship information I2 calculated based on the gas component information I1 transmitted from the gas supply facility 10 is transmitted from the center server 20 to the gas meter 30 in this manner, there is no need to add a gas component derivation function to the gas meter 30, as in the past. This reduces or prevents an increase in the cost of the gas meter 30 and an increase in the power consumption of the gas meter 30. Furthermore, since the center server 20 updates the gas calorific value relationship information I2 in accordance with fluctuations in the gas component information I1 and transmits the updated information to the gas meter 30, the calorific value of the gas can be derived with high accuracy even if the gas components vary depending on the time period. As described above, the information calculation unit 22 is configured to update the gas calorific value relationship information I2 in accordance with fluctuations in the gas component information I1, but the calorific value of the gas can be derived with higher accuracy if gas pressure fluctuations are also taken into consideration.

[0032] Second Embodiment Fig. 5 is a block diagram showing a heat generation amount deriving system 200 according to a second embodiment. In Fig. 5, the same components as those in Fig. 1 are given the same reference numerals, and descriptions thereof will be omitted unless otherwise noted.

[0033] 5, the calorific value derivation system 200 differs from the calorific value derivation system 100 according to the first embodiment in that it includes a gas meter 130 provided in the first supply path 50, a gas meter 131 provided in the first supply path 50 downstream of the gas meter 130, and a gas meter 132 provided in the second supply path 51 branching off from a portion of the first supply path 50 downstream of the gas meter 130. Another difference is that the center server 20A includes a pro rata acquisition unit 25. The gas meter 130 corresponds to the first gas meter, the gas meter 131 corresponds to the second gas meter, and the gas meter 132 corresponds to the third gas meter.

[0034] The gas meter 130 acquires an integrated value of the calorific value of the gas, as in the first embodiment. The gas meters 131 and 132 do not need to acquire their own integrated values ​​of the calorific values. The proration acquisition unit 25 receives an integrated value of the gas flow rate from the gas meter 131 and an integrated value of the gas flow rate from the gas meter 132, and also receives an integrated value of the calorific value from the gas meter 130. The proration acquisition unit 25 then acquires one calorific value obtained by prorating the calorific value received from the gas meter 130 based on the ratio between the integrated value of the flow rate received from the gas meter 131 and the integrated value of the flow rate received from the gas meter 132 as the calorific value of the gas meter 131, and acquires the other calorific value as the calorific value of the gas meter 132. For example, when the integrated value of the calorific value from the gas meter 130 is 10 and the ratio between the integrated value of the flow rate received from the gas meter 131 and the integrated value of the flow rate received from the gas meter 132 is 4:1, the pro rata acquisition unit 25 acquires the calorific value of the gas meter 131 as 8 and the calorific value of the gas meter 132 as 2. The storage unit 24 stores the calorific values ​​of the gas meters 130, 131, and 132 acquired by the pro rata acquisition unit 25. There may be three or more gas meters downstream of the gas meter 130.

[0035] 6 is a flowchart showing the flow of processing by the calorific value derivation system 200. As shown in FIG. 6, the component measurement unit 13 of the gas supply facility 10 measures the gas components and obtains gas component information I1 (step S11). Next, the first transmission unit 11 transmits the gas component information I1 to the center server 20A (step S12).

[0036] Next, the information calculation unit 22 of the center server 20A calculates the gas calorific value relationship information I2 based on the acquired gas component information I1 (step S13).Then, the second transmission unit 23 transmits the gas calorific value relationship information I2 to the gas meter 130 (step S14).

[0037] The flow meter unit 31 of each of the gas meters 130, 131, and 132 measures the gas flow rate (step S15). Next, the heat generation amount acquisition unit 34 of the gas meter 130 acquires the heat generation amount per predetermined time as an instantaneous heat generation amount based on the gas flow rate (instantaneous flow rate) and the heat generation coefficient, and acquires an integrated value of the heat generation amount by integrating the instantaneous heat generation amount per predetermined time (step S16).

[0038] Next, the third transmission unit 35 of the gas meter 130 transmits the acquired flow rate and heat generation value to the center server 20A, and the third transmission units 35 of the gas meters 131 and 132 transmit the acquired flow rates to the center server 20A (step S17). Then, the proration acquisition unit 25 of the center server 20A prorates the heat generation value received from the gas meter 130 into the heat generation value in the gas meter 131 and the heat generation value in the gas meter 132 based on the ratio between the integrated value of the flow rate received from the gas meter 131 and the integrated value of the flow rate received from the gas meter 132. Then, the memory unit 24 stores the integrated value of the gas flow rate in the gas meters 131 and 132 and the prorated heat generation value (step S18).

[0039] As described above, according to the second embodiment, in a configuration in which a gas meter 130 and a plurality of gas meters 30 (gas meter 131 and gas meter 132) are provided downstream of the gas meter 130, it is possible to obtain the calorific values ​​of the gas meters 131 and 132 simply by obtaining the integrated value of the calorific value in the gas meter 130 and the integrated values ​​of the flow rates in the gas meters 131 and 132. This eliminates the need to calculate the calorific values ​​individually in the gas meters 131 and 132 located at the ends, thereby reducing costs.

[0040] (Third embodiment) Fig. 7 is a block diagram showing a heat generation amount derivation system 300 according to a third embodiment. Fig. 8(a) is an explanatory diagram showing an example of first information If1, Fig. 8(b) is an explanatory diagram showing an example of second information If2, and Fig. 8(c) is an explanatory diagram showing an example of basic information Ifb. In Fig. 7, the same components as those in Fig. 1 above are assigned the same reference numerals, and descriptions thereof will be omitted unless otherwise noted.

[0041] As shown in FIG. 7 , the calorific value derivation system 300 differs from the calorific value derivation system 100 according to the first embodiment in that there are multiple gas supply facilities 10 that supply gas to one gas meter 30, and that the center server 20B includes an information acquisition unit 26 and a determination unit 27. In FIG. 7 , the multiple gas supply facilities 10 include a first gas supply facility 110 and a second gas supply facility 111. The number of multiple gas supply facilities 10 may be three or more. The first gas supply facility 110 and the gas meter 30 are connected by a first supply path 50. The second gas supply facility 111 and the first supply path 50 are connected by a second supply path 52. As a result, the second gas supply facility 111 and the gas meter 30 are connected to each other by the second supply path 52 and a portion of the first supply path 50. In this manner, two gas supply facilities 10 are connected to one gas meter 30.

[0042] Center server 20B has an information acquisition unit 26 and a determination unit 27. Based on gas component information I1 transmitted from first gas supply facility 110, information acquisition unit 26 calculates the propagation time of ultrasonic waves when the temperature is set to 0 degrees and the pressure is set to 1 atm as information related to the characteristics of the gas, and acquires the change in the propagation time over time as first information If1, as shown in FIG. 8( a). Furthermore, based on gas component information I1 transmitted from second gas supply facility 111, information acquisition unit 26 calculates the propagation time of ultrasonic waves when the temperature is set to 0 degrees as information related to the characteristics of the gas, and acquires the change in the propagation time over time as second information If2, as shown in FIG. 8( b).

[0043] The determination unit 27 acquires, as reference information Ifb, the change over time in propagation time as information related to the characteristics of the gas transmitted from the gas meter 30. Then, the determination unit 27 determines whether the gas being supplied to the gas meter 30 is being supplied from the first gas supply facility 110 or the second gas supply facility 11, based on a comparison between the reference information Ifb and the first information If1 and a comparison between the reference information Ifb and the second information If2. In this case, of the first information If1 in FIG. 8( a) and the second information If2 in FIG. 8( b), it is the first information If1 that matches the basic information Ifb in FIG. 8( c). Therefore, the determination unit 27 outputs the first gas supply facility 110 as the determination result.

[0044] The second transmission unit 23 transmits, depending on the determination result by the determination unit 27, either the gas calorific value relationship information I2 related to the gas supplied by the first gas supply facility 110 or the gas calorific value relationship information I2 related to the gas supplied by the second gas supply facility 111 to the gas meter 30. In the example of Fig. 8, the second transmission unit 23 transmits the gas calorific value relationship information I2 related to the first gas supply facility 110 to the gas meter 30. It should be noted that there may be two or more center servers 20B.

[0045] 9 is a flowchart showing the flow of processing by the calorific value derivation system 300. As shown in FIG. 9, the component measurement unit 13 of either of the gas supply facilities 110 and 111 measures the gas components and obtains gas component information I1 (step S21). Next, the first transmission unit 11 transmits the component information I1 to the center server 20B (step S22).

[0046] Next, the information calculation unit 22 of the center server 20B calculates the gas calorie relationship information I2 based on the acquired component information I1 (step S23). Then, the second transmission unit 23 transmits the gas calorie relationship information I2 to the gas meter 30 (step S24).

[0047] The flow meter unit 31 of the gas meter 30 measures the gas flow rate (step S25). Next, the calorific value acquisition unit 34 acquires the calorific value per predetermined time as the instantaneous calorific value based on the gas flow rate (instantaneous flow rate) and the calorific value coefficient, and acquires the integrated value of the calorific value by integrating the instantaneous calorific value per predetermined time (step S26).

[0048] Next, the third transmission unit 35 transmits the acquired flow rate and calorific value to the center server 20B (step S27). Subsequently, the determination unit 27 compares the reference information Ifb acquired as described above with the first information If1 acquired by the information acquisition unit 26, and compares the reference information Ifb with the second information If2 acquired by the information acquisition unit 26, to determine the gas supply facility 10 that is the supplier (step S28). Then, if the gas calorific value relationship information I2 related to the supplier as a result of the determination by the determination unit 27 differs from the gas calorific value relationship information I2 transmitted in step S24, the second transmission unit 23 retransmits the gas calorific value relationship information I2 related to the determination result to the gas meter 30 as updated information (step S29).

[0049] As described above, according to the third embodiment, the determination unit 27 determines whether the gas being supplied to the gas meter 30 is supplied from the first gas supply facility 110 or the second gas supply facility 111, based on a comparison between the reference information Ifb and the first information If1 and a comparison between the reference information Ifb and the second information If2. Then, the second transmission unit 23 transmits, to the gas meter 30, either the gas calorific value relationship information I2 related to the gas supplied from the first gas supply facility 110 or the gas calorific value relationship information I2 related to the gas supplied from the second gas supply facility 111, in accordance with the determination result by the determination unit 27. This allows the gas meter 30 to acquire the gas calorific value relationship information I2 corresponding to the gas currently being supplied, thereby enabling the calorific value to be calculated with high accuracy.

[0050] The present disclosure is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the present disclosure. For example, the following modifications are possible.

[0051] In the above embodiment, the third communication unit 32 is built into the gas meter 30, but this is not limited to this, and the third communication unit 32 may be provided independently of the gas meter 30. In addition, the first communication unit 12 is built into the gas supply facility 10, but the first communication unit 12 may be provided independently of the gas supply facility 10. Furthermore, the second communication unit 21 is built into the center server 20, but the second communication unit 21 may be provided independently of the center server 20.

[0052] In the above embodiment, the gas heat quantity relationship information I2 shows the correlation between the heat quantity and the propagation time of ultrasonic waves as information related to the characteristics of the gas, but this is not limited to this, and other information related to the characteristics of the gas, such as the absorption rate of light waves, may also be used.

[0053] In addition, in the above embodiment, an ultrasonic type flow measurement unit 31 is used, but this is not limited to this, and other types of flow meter units such as a differential pressure flow meter or a thermal flow meter may also be used.

[0054] REFERENCE SIGNS LIST 10 Gas supply facility 11 First transmission unit 12 First communication unit 13 Component measurement unit 20, 20A, 20B Center server 21 Second communication unit 22 Information calculation unit 23 Second transmission unit 24 Memory unit 25 Allocation acquisition unit 26 Information acquisition unit 27 Discrimination unit 30 Gas meter 31 Flow meter side unit 32 Third communication unit 33 Calorific value coefficient calculation unit 34 Calorific value acquisition unit 35 Third transmission unit 36 ​​Memory unit 50 First supply path 51 Second supply path 52 Second supply path 100 Calorific value derivation system 110 First gas supply facility 111 Second gas supply facility 130, 131, 132 Gas meter I1 Gas component information I2 Gas calorific value related information

Claims

1. A calorific value derivation system comprising a gas supply facility, a center server, and a gas meter, comprising: a first communication unit provided within the gas supply facility or separately from the gas supply facility and communicating with the outside; a second communication unit built into the center server or provided separately from the center server and communicating with the outside; and a third communication unit built into the gas meter or provided separately from the gas meter and communicating with the outside; the gas supply facility has a first transmission control unit that controls the transmission of component information of the gas to the center server via the first communication unit; the center server has: an information calculation unit that calculates gas calorific value relationship information indicating a relationship between characteristics of the gas and a calorific value based on the gas component information acquired via the second communication unit, and newly calculates the gas calorific value relationship information in accordance with fluctuations in the gas component information; and a second transmission control unit that controls the transmission of the gas calorific value relationship information to the gas meter via the second communication unit; and the gas meter has: a flow measurement unit that measures a flow rate of the gas based on the characteristics of the gas; a heat quantity coefficient calculation unit that calculates a heat quantity coefficient based on the gas heat quantity relationship information acquired via the third communication unit; a heat quantity acquisition unit that acquires an instantaneous heat quantity based on the gas flow rate and the heat quantity coefficient, and acquires the heat quantity of the gas by integrating the instantaneous heat quantity at predetermined time intervals; and a third transmission control unit that controls the transmission of the flow rate and the heat quantity to the center server via the third communication unit.

2. The heat generation amount derivation system of claim 1, wherein the gas meters include: a first gas meter provided in a first supply line; a second gas meter provided in the first supply line downstream of the first gas meter; and a third gas meter provided in a second supply line branching off from a portion of the first supply line downstream of the first gas meter, and the center server further has an allocation acquisition unit that acquires one heat generation amount obtained by apportioning the heat generation amount received from the first gas meter based on a ratio between the integrated value of the flow rate received from the second gas meter and the integrated value of the flow rate received from the third gas meter as the heat generation amount in the second gas meter, and acquires the other heat generation amount as the heat generation amount in the third gas meter.

3. The gas supply facility includes a first gas supply facility and a second gas supply facility as a plurality of gas supply facilities that supply gas to one of the gas meter, and the center server further has an information acquisition unit that acquires information on characteristics of the gas as first information based on component information of the gas supplied by the first gas supply facility and acquires information on characteristics of the gas as second information based on component information of the gas supplied by the second gas supply facility, and a determination unit that receives the information on characteristics of the gas supplied to the gas meter as reference information via the second communication unit and determines from which of the first gas supply facility and the second gas supply facility the gas supplied to the gas meter is supplied, based on a comparison between the reference information and the first information and a comparison between the reference information and the second information; The calorific value derivation system of claim 1 or 2, wherein the second transmission control unit transmits to the gas meter either the gas calorific value relationship information relating to the gas supplied by the first gas supply facility or the gas calorific value relationship information relating to the gas supplied by the second gas supply facility depending on the determination result by the determination unit.