JP2016053458A - Hydrogen gas cooling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To supply a sufficient amount of a heat transfer liquid while suppressing a steep rise in a manufacturing cost.SOLUTION: A hydrogen gas cooling device comprises a plurality of refrigeration units 2, and a plurality of liquid feed pumps 6 (6a, 6b) connected to the units 2 (2a-2d). When both the units 2 satisfy a first condition that refrigerant overheating degrees of evaporators of both the units 2 each connected to any of the pumps 6 are equal to or lower than a first temperature, any of the pumps 6 is put into operation. When either one of both the units 2 connected to the pumps 6 in operation satisfies a second condition that the refrigerant overheating degree of the evaporator is equal to or higher than a second temperature while one or more pumps 6 are in operation without cooling a hydrogen gas or while two or more pumps 6 are in operation to cool the hydrogen gas, only one pump 6 is stopped. When either one of both the units 2 connected to the pumps 6 in operation satisfies the second condition while only one pump 6 is in operation to cool the hydrogen gas, the pump 6 is made to continue to operate.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a circulation type hydrogen gas cooling apparatus configured to supply a heat medium liquid cooled by a refrigeration unit to a hydrogen gas cooling heat exchanger so that the hydrogen gas can be cooled in the hydrogen gas cooling heat exchanger. It is.

  For example, the following Patent Document 1 discloses a fuel filling device that fills an automobile or the like with hydrogen gas as a fuel. In this case, hydrogen gas generated in the field (in the case of an on-site type station), or in order to store a sufficient amount of hydrogen gas in a gas station where this kind of fuel filling device is installed, or A configuration is adopted in which hydrogen gas generated and transported elsewhere (in the case of an off-site type station) is stored in a gas tank in a sufficiently compressed state. Further, when hydrogen gas is charged into an automobile or the like, the gas tank of the automobile (hereinafter referred to as “vehicle side”) is supplied from the gas tank of the gas station (hereinafter also referred to as “storage tank”) through an air supply pipe and an air supply nozzle. Hydrogen gas is allowed to flow into the tank.

  At this time, it is known that hydrogen gas has a property of increasing in temperature due to the Joule-Thompson effect when it is adiabatically expanded when passing through various valves disposed in an air supply pipe or the like. ing. For this reason, when the vehicle side tank is simply filled with hydrogen gas from the storage tank, the high temperature hydrogen gas whose temperature has risen when passing through the air supply pipe or the like flows into the vehicle side tank. Further, when hydrogen gas is allowed to flow from the gas station into the low-pressure vehicle side tank that has been consumed, the hydrogen gas that has flowed in is adiabatically expanded in the vehicle-side tank and the temperature further rises. . For this reason, the charging efficiency of hydrogen gas into the vehicle-side tank is reduced, and as a result, it becomes difficult to fill the vehicle-side tank with a sufficient amount of hydrogen gas. Therefore, the fuel filling device disclosed in Patent Document 1 employs a configuration that avoids a reduction in filling efficiency by cooling the hydrogen gas prior to filling the vehicle-side tank.

  Specifically, in the fuel filling device disclosed in Patent Document 1, a flow rate adjustment valve, an integrated flow meter, a shutoff valve, and the like are arranged in a supply path for supplying hydrogen gas from a hydrogen gas storage tank (storage tank) to an automobile or the like. In addition, a cooling means (heat exchanger) for cooling hydrogen gas is disposed between a connecting pipe (flexible hose) connected to an automobile or the like and the shut-off valve. In this case, in this fuel filling device, a chiller cooler using ethylene glycol as a refrigerant is employed as the cooling means. As a result, in this fuel filling device, the hydrogen gas in the storage tank adiabatically expands when passing through the flow regulating valve, the integrating flow meter, the shutoff valve, etc., but the temperature is lowered due to heat exchange with ethylene glycol in the cooling means. In this state, it is allowed to flow into the vehicle-side tank through the connecting pipe, so that it is possible to avoid a decrease in filling efficiency to some extent.

  On the other hand, the applicant applied a refrigerant such as ethylene glycol cooled by a chiller cooler in the same manner as the configuration of the fuel filling device disclosed in Patent Document 1 (hereinafter referred to as “heating medium liquid” to distinguish it from the refrigerant in the refrigeration circuit). In other words, an attempt was made to fill the hydrogen gas by making a prototype of an apparatus configured to fill the vehicle-side tank after cooling the hydrogen gas. However, a chiller cooler that uses ethylene glycol as the heat transfer fluid (a chiller cooler whose lower limit temperature of the heat transfer fluid cooled by the refrigeration circuit is higher than the freezing temperature of ethylene glycol) sufficiently cools the hydrogen gas in a short time. It has been found that it is difficult to sufficiently improve the charging efficiency of hydrogen gas into the vehicle-side tank. Therefore, the applicant adopts a heat transfer liquid whose freezing temperature is lower than that of ethylene glycol, and chiller cooling equipped with a refrigeration circuit that uses an inert gas that can cool the heat transfer liquid to such an extremely low temperature as a refrigerant. An attempt was made to cool the heat transfer fluid with a vessel to cool the hydrogen gas.

  However, in a chiller cooler having a refrigeration circuit capable of cooling the heat transfer liquid to an extremely low temperature, the refrigerant temperature in the refrigeration circuit is increased to the same level as the outside air temperature (for example, the chiller cooler is kept for a long time). When the cooling of the heat transfer liquid is started, it takes a very long time until the temperature of the evaporator is sufficiently lowered and the thermal refrigerant can be cooled to an extremely low temperature. For this reason, the applicant uses a condenser of a refrigeration circuit (hereinafter also referred to as “low temperature side refrigeration circuit”) for cooling the thermal refrigerant to an extremely low temperature, and a refrigeration circuit (hereinafter referred to as “high temperature side refrigeration”) having a high refrigeration capacity in a normal temperature range. The heat transfer fluid is cooled by a chiller cooler equipped with a refrigeration unit having a “binary refrigeration circuit” that improves the cooling efficiency of the low-temperature refrigeration circuit by cooling with an evaporator of the “circuit”. Tried to cool. As a result, for example, even when the chiller cooler has been stopped for a long time, it has become possible to sufficiently shorten the time required for cooling the heat transfer fluid to an extremely low temperature.

  In this case, for example, when a large amount of hydrogen gas is charged into one vehicle, or when hydrogen gas is continuously charged into a plurality of vehicles, a cryogenic heat transfer fluid is supplied to the heat exchanger. On the other hand, it is necessary to supply continuously over a long time. In addition, when charging hydrogen gas to a plurality of vehicles simultaneously (in parallel), a cryogenic heat medium liquid is supplied in parallel to a plurality of heat exchangers (a large amount of heat medium liquid is supplied). Need). For this reason, this type of chiller cooler has a refrigerating capacity so that a large amount of the heat transfer fluid whose temperature has been increased by cooling the hydrogen gas can be quickly lowered to an extremely low temperature suitable for cooling the hydrogen gas. It is necessary to provide a sufficiently high refrigeration circuit.

  However, in order to be able to cool a large amount of heat transfer fluid in a short time, a large-scale refrigeration circuit (a refrigerating circuit in which each component is sufficiently large and a large amount of heat transfer fluid can be cooled in a short time with a large amount of refrigerant) ) For example, when hydrogen gas is not supplied for a long time or when a small amount of hydrogen gas is charged into a small number of vehicles (a large amount of heat transfer fluid is added). Energy is wasted by operating a large compressor in the refrigeration circuit when it is not necessary to cool.

  On the other hand, by intermittently operating the refrigeration circuit when it is not necessary to cool a large amount of heat transfer fluid (by repeatedly repeating the stopped state and the operating state), only the time for which the compressor or the like is stopped It becomes possible to reduce energy consumption. However, since a large compressor mounted on a large refrigeration circuit consumes a large amount of energy when starting operation from a stopped state, if the stopped state and the operating state are repeated in a short cycle, the energy consumption is reduced. It becomes difficult to reduce consumption appropriately. In addition, a large refrigeration circuit takes a long time from the start of operation until the heat transfer fluid can be sufficiently cooled. For this reason, for example, even if the frozen refrigeration circuit is restarted when hydrogen gas is charged and the temperature of the heat transfer liquid suddenly increases, the heat transfer liquid reaches a temperature suitable for cooling of the hydrogen gas. As a result, it takes a long time to lower the temperature, and it may be difficult to suitably cool the hydrogen gas.

  Therefore, the applicant has a refrigeration unit having a small refrigeration circuit that consumes less power at the time of starting the compressor and has a short time required to sufficiently cool the heat transfer fluid from the start of operation. The chiller cooler has been improved to cool the heat transfer fluid with multiple units. Thereby, for example, when it is necessary to cool a large amount of hydrogen gas, it becomes possible to cool a large amount of the heat transfer fluid in a short time by cooling the heat transfer fluid in parallel by a plurality of refrigeration units, When there is no need to cool a large amount of heat transfer fluid, it is possible to avoid wasting energy by stopping any of the multiple refrigeration units and cooling the heat transfer fluid with the remaining refrigeration units. became.

JP 2004-116619 A (page 4-10, FIG. 1-6)

  However, the chiller cooler in which the applicant has improved the configuration of the chiller cooler in the fuel filling device disclosed in Patent Document 1 for the purpose of cooling hydrogen gas has the following problems to be improved. . In other words, the chiller cooler developed by the applicant has a configuration in which a plurality of refrigeration units are provided so that the heat transfer fluid can be cooled in parallel, and the number of refrigeration units operated is changed according to the required refrigeration capacity. Has been. Further, in this type of chiller cooler, the heat medium liquid cooled by the refrigeration unit is liquid-fed by a liquid feed pump to a heat exchanger for cooling hydrogen gas, so that the heat medium is transferred between the refrigeration unit and the heat exchanger. A configuration in which the liquid is circulated (a configuration in which the heat medium liquid is recovered from the heat exchanger by supplying the heat medium liquid to the heat exchanger by a liquid feed pump, and the recovered heat medium liquid is supplied to the refrigeration unit again). It has been adopted.

  In this case, in the chiller cooler having a plurality of refrigeration units such as the chiller cooler improved by the applicant, the heat medium liquid cooled by each refrigeration unit is heated by the single liquid feed pump for cooling hydrogen gas. When adopting a configuration for supplying to the exchanger, for example, hydrogen gas filling is performed in a state where one of the plurality of refrigeration units is stopped, and the temperature of the heat transfer liquid increases rapidly. In response, when the stopped refrigeration unit is restarted, the heat medium liquid fed by the liquid feed pump is in operation and the refrigeration unit that is in operation (the heat medium liquid can be sufficiently cooled). Not only the refrigeration unit) but also the refrigeration unit in a state in which it is difficult to sufficiently cool the heat transfer fluid immediately after re-operation.

  For this reason, in a chiller cooler having a plurality of refrigeration units and configured to feed the heat transfer liquid cooled by each refrigeration unit by one liquid feed pump, the chiller cooler is sufficiently supplied to the refrigeration unit immediately after restart. By supplying uncooled heat transfer fluid to the refrigeration unit that was in operation, it is supplied to the heat exchanger for cooling hydrogen gas in a state of being mixed with the sufficiently cooled heat transfer fluid. As a result, it may be difficult to suitably cool the hydrogen gas. On the other hand, instead of a configuration in which the heat transfer liquid is fed to a plurality of refrigeration units by a single liquid feed pump, a liquid feed pump is separately provided for each refrigeration unit, and depending on the state of each refrigeration unit By adopting a configuration in which each liquid feed pump is operated / stopped separately, the heat medium liquid is supplied to the refrigeration unit in a state immediately after re-operation and in which it is difficult to sufficiently cool the heat medium liquid. It becomes possible to avoid the situation. However, in such a configuration, it is difficult to reduce the manufacturing cost of the chiller cooler due to the need for as many liquid feed pumps as the number of refrigeration units.

  The present invention has been made in view of such problems to be improved, and it is possible to reliably supply a sufficient amount of heat transfer liquid to a heat exchanger for cooling a hydrogen gas as necessary while suppressing an increase in manufacturing cost. The main object of the present invention is to provide a hydrogen gas cooling device that can be supplied to the vehicle.

  In order to achieve the above object, the hydrogen gas cooling device according to claim 1 cools the condenser of the low temperature side refrigeration circuit by the first evaporator in the high temperature side refrigeration circuit and the second evaporation in the low temperature side refrigeration circuit. A plurality of refrigeration units having a dual refrigeration circuit configured to cool the heat transfer fluid by a cooler, and the heat transfer fluid circulation for circulating the heat transfer fluid between each of the refrigeration units and the heat exchanger for cooling hydrogen gas A heat medium liquid pipe constituting the path, and the heat medium liquid connected to the heat medium liquid pipe and cooled by the respective refrigeration units is supplied to the heat exchanger for cooling the hydrogen gas and the heat exchange for cooling the hydrogen gas A plurality of liquid feed pumps for recovering the heat transfer fluid from the container, and a control unit for controlling the operation of each of the refrigeration units and the liquid feed pump, each of the liquid feed pumps via the heat transfer fluid pipe. Phase with each other Supplying the heat transfer fluid that is connected to each of the plurality of refrigeration units and cooled by each refrigeration unit to the hydrogen gas cooling heat exchanger according to the control of the control unit, and the control unit While performing a refrigeration capacity adjustment process for adjusting the refrigeration capacity of each refrigeration unit so that the temperature of the heat medium liquid at a predetermined position in the liquid medium flow path is a temperature within a predetermined temperature range. When the temperature difference between the inlet-side refrigerant temperature and the outlet-side refrigerant temperature in the second evaporator of each refrigeration unit connected to any one of the liquid feed pumps is equal to or lower than a first temperature specified in advance. When the first condition is substantially satisfied in all of the respective refrigeration units, one of the liquid feed pumps is operated, and the hydrogen gas is cooled in the hydrogen gas cooling heat exchanger. A state in which at least one liquid feed pump is operated without rejection, and a state in which two or more liquid feed pumps are operated to cool the hydrogen gas in the hydrogen gas cooling heat exchanger The temperature difference between the inlet side refrigerant temperature and the outlet side refrigerant temperature in the second evaporator of each refrigeration unit connected to any one of the liquid feed pumps operating in any one of When the second condition that the temperature is equal to or higher than a predetermined second temperature higher than the temperature is substantially satisfied in any one of the refrigeration units, the refrigeration unit is connected to the refrigeration unit. Only one liquid feed pump is stopped and only one liquid feed pump is operated to cool the hydrogen gas in the hydrogen gas cooling heat exchanger. When the second condition is substantially satisfied in any of the connected refrigeration units, the operating state is maintained without stopping the liquid feed pump in operation.

  The hydrogen gas cooling device according to claim 2 is the hydrogen gas cooling device according to claim 1, wherein the high temperature side refrigeration circuit includes a third evaporator capable of cooling the heat transfer fluid, and the first evaporator. And a refrigerant supply amount adjusting valve for adjusting a supply amount of the refrigerant to the third evaporator, and the heat medium liquid pipe is configured so that the heat medium liquid is the third evaporator and the second evaporator. The evaporators are connected to each of the refrigeration units so as to pass in this order, and the controller is configured so that the temperature of the heat transfer liquid at the predetermined position is the predetermined temperature range. When the condition A that the temperature is equal to or higher than a predetermined temperature is substantially satisfied, the third evaporator does not cool the heating medium liquid by the second evaporator. The process A for cooling the heat transfer liquid and the pre-defined position The refrigerant supplied to the first evaporator is controlled by controlling the refrigerant supply amount adjusting valve when the condition B that the temperature of the heat transfer liquid is lower than the predetermined temperature is substantially satisfied. Process B for cooling the heat transfer fluid by the second evaporator while cooling the condenser by the first evaporator while increasing the supply amount of the process A from the execution time of the process A Any of the other refrigeration units connected to the liquid feed pump to which the refrigeration unit is executed and the process A is executed in any of the refrigeration units. When the process B is being executed in any one of the other refrigeration units based on the temperature difference between the inlet side refrigerant temperature and the outlet side refrigerant temperature in the second evaporator of the other refrigeration unit. DOO and the other one of the refrigeration unit to determine whether to stop operating the liquid feed pump connected.

  A hydrogen gas cooling device according to claim 3 is configured to be capable of storing the heat transfer fluid recovered from the hydrogen gas cooling heat exchanger and storing the liquid in the hydrogen gas cooling device according to claim 1 or 2. The first liquid storage tank disposed so as to be able to supply the heat medium liquid to each of the refrigeration units, and the heat medium liquid cooled by the refrigeration unit are configured to be capable of storing liquid and stored. At least one storage tank of a second storage tank disposed so as to be able to supply a heat transfer fluid to the heat exchanger for cooling the hydrogen gas, and the heat storage liquid disposed in the at least one storage tank. A temperature sensor that detects a temperature of the liquid medium, and the control unit determines a temperature of the heat medium liquid specified based on a sensor signal from the temperature sensor at a temperature that is defined in advance. As specified.

  The hydrogen gas cooling device according to claim 1 includes a plurality of refrigeration units and a plurality of liquid feed pumps, and each liquid feed pump can supply a heat transfer fluid from the plurality of refrigeration units to the heat exchanger for cooling the hydrogen gas. Each refrigeration unit connected to one of the liquid feed pumps is connected to a plurality of refrigeration units different from each other, and the control unit executes a refrigeration capability adjustment process for adjusting the refrigeration capability of each refrigeration unit. The first condition that the temperature difference between the inlet-side refrigerant temperature and the outlet-side refrigerant temperature in the second evaporator of the unit is equal to or lower than the first predetermined temperature is substantially satisfied in all the refrigeration units. One of the liquid feed pumps is operated, at least one liquid feed pump is operated without cooling the hydrogen gas in the hydrogen gas cooling heat exchanger, and two or more The second evaporator of each refrigeration unit connected to one of the liquid feed pumps operating in any of the states where the feed pump is operated to cool the hydrogen gas in the hydrogen gas cooling heat exchanger In each of the refrigeration units, the second condition that the temperature difference between the inlet-side refrigerant temperature and the outlet-side refrigerant temperature is equal to or higher than a predetermined second temperature that is higher than the first temperature. When it is satisfied, only one liquid feed pump connected to one of the refrigeration units is stopped, and only one liquid feed pump is operated to cool the hydrogen gas in the heat exchanger for cooling hydrogen gas. When the second condition is substantially satisfied in any of the refrigeration units connected to the operating liquid feed pump in a state where the operating liquid feed pump is operating without stopping the operating liquid feed pump To maintain.

  Therefore, according to the hydrogen gas cooling device of the first aspect, unlike the hydrogen gas cooling device configured to supply the heat medium liquid to a plurality of refrigeration units by one liquid feed pump, the heat medium liquid is suitable. Suitable for situations in which heat transfer fluid is supplied to a refrigeration unit that is not in a state that can be cooled to a low temperature, or in situations where high temperature heat transfer fluid is supplied to a refrigeration unit that may overload the low temperature side refrigeration circuit The heating medium liquid is supplied only to the refrigeration unit in which the low temperature side refrigeration circuit is not likely to be overloaded and the heating medium liquid can be suitably cooled. Can be suitably cooled. In addition, since the number of liquid feed pumps constituting the hydrogen gas cooling device is small compared to a hydrogen gas cooling device having a plurality of liquid feed pumps having the same number as the number of refrigeration units, the hydrogen gas cooling device The increase in manufacturing cost can be sufficiently suppressed. Furthermore, when the hydrogen gas is being cooled in the hydrogen gas cooling heat exchanger, a sufficient amount of the heat transfer liquid necessary for cooling the hydrogen gas is supplied by at least one liquid feed pump. Therefore, hydrogen gas can be reliably cooled in the heat exchanger for cooling hydrogen gas. In addition, when supplying a small amount of heat transfer fluid to the heat exchanger for cooling the hydrogen gas, the liquid supply pump is stopped by operating a small number of liquid transfer pumps to supply a small amount of heat transfer fluid. The amount of energy consumption can be reduced by that amount.

  Moreover, in the hydrogen gas cooling device according to claim 2, the condition that the controller is equal to or higher than a predetermined temperature within a predetermined temperature range at a predetermined position. A process A for cooling the heat transfer liquid by the third evaporator without cooling the heat transfer liquid by the second evaporator when A is substantially satisfied, and a heat transfer medium at a predetermined position; When the condition B that the temperature of the liquid is lower than a predetermined temperature is substantially satisfied, the refrigerant supply amount adjusting valve is controlled to process the refrigerant supply amount to the first evaporator A And the process B of cooling the heat transfer fluid by the second evaporator while cooling the condenser by the first evaporator and performing the cooling capacity adjustment process, and either refrigeration unit And execute processing A in any one of When the process B is being executed in any of the other refrigeration units connected to the liquid feed pump to which the knit is connected, the inlet side refrigerant temperature in the second evaporator of any of the other refrigeration units Based on the temperature difference from the outlet side refrigerant temperature, it is determined whether to operate or stop the liquid feed pump to which any of the refrigeration units and any of the other refrigeration units are connected.

  Therefore, according to the hydrogen gas cooling device of claim 2, when the temperature of the heat transfer liquid is high, the low temperature side refrigerating circuit is executed by executing the process A that does not execute the cooling of the heat transfer liquid by the low temperature side refrigerating circuit. This can not only reliably avoid the situation where the compressor is damaged or the emergency stop of the low temperature side refrigeration circuit to avoid the compressor being damaged, but also the high temperature side where the cooling efficiency of the high-temperature heat transfer fluid is high Cooling the heat transfer fluid with the refrigeration circuit reduces the temperature of the hot heat transfer fluid in a short time, and executes process B when the temperature of the heat transfer fluid drops to a temperature that can be suitably cooled by the low temperature side refrigeration circuit Since the heat transfer fluid can be cooled to the target temperature by cooling the heat transfer fluid with the low temperature side refrigeration circuit, the high temperature heat transfer fluid can be reliably cooled to the target temperature in a short time, Any liquid feed pump The liquid feed pump connected to the refrigeration unit when the superheat degree of the refrigerant in the second evaporator of the refrigeration unit executing the process B among the refrigeration units connected to is equal to or higher than the first temperature Is stopped and the supply of the heat transfer fluid to the refrigeration unit is stopped, so that it is possible to reliably avoid the low temperature side refrigeration circuit executing the processing B from being in a high load state.

  Furthermore, according to the hydrogen gas cooling device of claim 3, the heat medium liquid recovered from the heat exchanger for cooling the hydrogen gas is configured to be stored, and the stored heat medium liquid can be supplied to each refrigeration unit. The first liquid storage tank disposed in the tank and the heat transfer medium cooled by the refrigeration unit can be stored, and the stored heat transfer liquid can be supplied to the heat exchanger for cooling the hydrogen gas. The temperature of the heat transfer fluid at the position where the temperature of the heat transfer solution specified based on the sensor signal from the temperature sensor disposed in at least one of the provided second storage reservoirs is set in advance. For example, the temperature of the heat transfer fluid at a position different from the predefined position is monitored, the temperature of the heat transfer fluid at the predefined position is calculated, and the condition A is calculated based on the calculated temperature. And whether the condition B is satisfied and the process A Unlike the hydrogen gas cooling apparatus configured to execute either of the process B and the process B, it is directly determined whether the condition A or the condition B is satisfied based on the temperature of the heat transfer liquid specified by the sensor signal from the temperature sensor. Therefore, it is possible to cool the heat transfer liquid efficiently by accurately executing either the process A or the process B without executing a complicated calculation process.

It is a block diagram which shows the structure of the hydrogen gas cooling device 1 which concerns on embodiment of this invention. It is a block diagram which shows the structure of the freezing unit 2a-2d in the hydrogen gas cooling device 1 which concerns on embodiment of this invention.

  Hereinafter, embodiments of a hydrogen gas cooling device will be described with reference to the accompanying drawings.

  First, the configuration of the hydrogen gas cooling device 1 will be described with reference to the accompanying drawings.

  A hydrogen gas cooling device (hydrogen gas cooling chiller) 1 shown in FIG. 1 is an example of a “hydrogen gas cooling device”, and includes refrigeration units 2a to 2d, a hydrogen gas cooling heat exchanger 3, a brine tank 4, and a brine. The pipe 5, the liquid feed pumps 6 a and 6 b, and the control unit 7 are installed in the gas station together with the gas station side equipment X, and air is supplied to an air supply target such as a hydrogen fuel cell vehicle (not shown) by the gas station side equipment X. The hydrogen gas to be cooled can be cooled in the hydrogen gas cooling heat exchanger 3.

  In the figure, in order to facilitate the understanding of the relationship between the hydrogen gas cooling device 1 and the gas station side equipment X, the gas station side equipment X has a gas tank (storage tank) for storing hydrogen gas. ) Only Xa, a dispenser Xb that can be connected to an air supply port provided in an automobile such as a hydrogen fuel cell vehicle (not shown), and a gas pipe Xc that connects the gas tank Xa and the dispenser Xb to each other, are shown in the figure. Illustration of a flow rate adjusting valve, a flow meter, a shutoff valve, and the like disposed in the pipe Xc is omitted.

  On the other hand, the refrigeration units 2a to 2d (hereinafter also referred to as “refrigeration units 2” when not distinguished from each other) are an example of “a plurality of refrigeration units”, and as shown in FIG. A “binary refrigeration circuit” composed of the refrigeration circuit 20 is provided so that the brine (heat medium liquid) can be cooled. The high temperature side refrigeration circuit 10 includes a compressor 11, a condenser 12, an electromagnetic valve 13a, an electronic expansion valve 13b, an evaporator 14, an electromagnetic valve 15a, an electronic expansion valve 15b, and an evaporator 16. In this case, a condenser fan (not shown) that cools the condenser 12 according to the control of the control unit 7 is attached to the condenser 12. Furthermore, the low temperature side refrigeration circuit 20 includes a compressor 21, a condenser 22, an electronic expansion valve 23, and an evaporator 24. In this case, a temperature sensor 24 a that detects the “inlet-side refrigerant temperature” and outputs a sensor signal S 24 a is attached in the vicinity of the refrigerant inlet of the evaporator 24, and in the vicinity of the refrigerant outlet of the evaporator 24. A temperature sensor 24b for detecting the “exit-side refrigerant temperature” and outputting a sensor signal S24b is attached.

  In the refrigeration unit 2 of this example, the evaporator 14 of the high temperature side refrigeration circuit 10 corresponds to the “first evaporator”, and the condenser 22 corresponding to the “condenser of the low temperature side refrigeration circuit” is cooled. In this case, in the refrigeration unit 2 of the present example, as an example, the evaporator 14 and the condenser 22 are integrally configured by the cascade condenser 30, thereby cooling the condenser 22 by the evaporator 14 as described later. The structure to be adopted is adopted. Further, in the refrigeration unit 2 of this example, the evaporator 24 of the low temperature side refrigeration circuit 20 corresponds to a “second evaporator”, and cools the brine supplied via the brine pipe 5 as will be described later. Further, in the refrigeration unit 2 of the present example, the evaporator 16 of the high temperature side refrigeration circuit 10 corresponds to a “third evaporator”, and cools the brine supplied through the brine pipe 5 as will be described later.

  Further, in the refrigeration unit 2 of this example, the “refrigerant supply amount adjustment valve” is configured by the electromagnetic valves 13 a and 15 a and the electronic expansion valves 13 b and 15 b. Specifically, in the refrigeration unit 2 of this example, the supply amount of the refrigerant to the evaporator 14 is adjusted by changing the open / close state of the electromagnetic valve 13a and the opening of the electronic expansion valve 13b, and the electromagnetic valve 15a A configuration is adopted in which the supply amount of the refrigerant to the evaporator 16 is adjusted by changing the open / close state and the opening of the electronic expansion valve 15b. In this case, when the electronic expansion valves 13b and 15b in the refrigeration unit 2 of this example are completely closed when the refrigerant can be completely blocked, the electromagnetic valves 13a and 15a are not required. You can also. Further, instead of the electronic expansion valves 13b and 15b, a capillary tube can be provided as an “expansion valve” in the “refrigeration circuit”. In this case, the electromagnetic valves 13a and 15a are arranged upstream of the capillary tube. It is preferable to provide an “open / close valve” similar to the above, so that the amount of refrigerant supplied to the evaporators 14 and 16 can be adjusted (not shown). In order to facilitate understanding of the configuration of the hydrogen gas cooling device 1 (each refrigeration unit 2), illustrations and explanations regarding components other than the above-described components in the high temperature side refrigeration circuit 10 and the low temperature side refrigeration circuit 20 are provided. Is omitted.

  The hydrogen gas cooling heat exchanger 3 is an example of a “hydrogen gas cooling heat exchanger”, and, as shown in FIG. 1, between the gas tank Xa and the dispenser Xb in the gas station side equipment X (gas piping Xc). It is arranged. This hydrogen gas cooling heat exchanger 3 performs heat exchange between the brine cooled by the refrigeration unit 2 and supplied via the brine pipe 5 and the hydrogen gas supplied from the gas tank Xa via the gas pipe Xc. As a result, the hydrogen gas immediately before filling the automobile or the like from the dispenser Xb is cooled to a predetermined temperature (as an example, a temperature within a temperature range of −33 ° C. to −40 ° C.). In this case, in the hydrogen gas cooling device 1 of this example, the temperature sensor 3a that detects the temperature of the brine in the hydrogen gas cooling heat exchanger 3 and outputs the sensor signal S3a is provided in the hydrogen gas cooling heat exchanger 3. It is arranged.

  In this example, a configuration in which hydrogen gas is cooled in the gas station side equipment X including one dispenser Xb will be described. However, when supplying hydrogen gas from the gas tank Xa to a plurality of dispensers Xb, an example is given. As an alternative, a hydrogen gas cooling heat exchanger 3 may be provided for each dispenser Xb (not shown). Further, the hydrogen gas cooling device 1 of the present example is configured integrally with a hydrogen gas cooling heat exchanger 3 which is an example of a “hydrogen gas cooling heat exchanger”. It is also possible to adopt a configuration in which the brine is supplied to the “hydrogen gas cooling heat exchanger” as an external device by excluding the hydrogen gas cooling heat exchanger 3 from the configuration described above. In such a configuration, the temperature sensor 3a may be disposed in a “hydrogen gas cooling heat exchanger” as an external device.

  The brine tank 4 is an example of a “first storage tank” as “at least one storage layer”, and is configured to be able to store the brine recovered from the heat exchanger 3 for cooling the hydrogen gas. The stored brine is connected to the brine pipe 5 so that it can be supplied to each refrigeration unit 2. Specifically, in the hydrogen gas cooling device 1 of this example, a hydrogen gas cooling heat exchanger is provided between the brine outlet in the hydrogen gas cooling heat exchanger 3 and the brine inlet in each refrigeration unit 2. 3 is disposed. In this case, in the hydrogen gas cooling device 1 of this example, the temperature of the brine in the brine tank 4 is detected by setting the inside of the brine tank 4 as “predetermined position in the heat transfer medium circulation path”, and the sensor signal S4a. A temperature sensor 4 a (an example of a “temperature sensor”) that outputs “” is disposed in the brine tank 4.

  The brine pipe 5 is an example of a “heat medium liquid pipe constituting a heat medium liquid circulation path”, and includes a pipe 5 a that interconnects the brine tank 4 and each refrigeration unit 2 (evaporator 16), and each refrigeration unit. 2, a pipe 5b connecting the evaporators 16 and 24 to each other (“the two evaporators are mutually connected for each refrigeration unit so that the heat medium liquid passes through the third evaporator and the second evaporator in this order. An example of the configuration of “is connected to”: refer to FIG. 2), piping 5 c that interconnects each refrigeration unit 2 (evaporator 24) and the three-way valves Va and Vb, three-way valves Va and Vb, and hydrogen gas cooling 5d for connecting the heat exchanger 3 for use with each other, and 5e for connecting the heat exchanger 3 for cooling the hydrogen gas and the brine tank 4 with each other. The brine tank 4, each refrigeration unit 2 and hydrogen gas cooling are provided. Circulating brine between heat exchangers 3 And it is configured to be able to.

  Further, the hydrogen gas cooling device 1 of the present example includes a pair of pipes 5f and 5f that connect the three-way valves Va and Vb and the pipe 5e to each other, and the two-way valve Vc is disposed in the pipe 5d. Yes. In this case, in the hydrogen gas cooling device 1 of this example, the three-way valves Va and Vb are constituted by variable flow rate type valves, and the two-way valve Vc is constituted by a variable aperture ratio type valve. Thereby, in the hydrogen gas cooling device 1 of this example, as will be described later, the control unit 7 controls the three-way valves Va and Vb and the two-way valve Vc, whereby the heat exchanger for cooling the hydrogen gas from each refrigeration unit 2. 3 is used to adjust the amount of brine supplied to 3.

  In the hydrogen gas cooling device 1 of this example, two of the refrigeration units 2a and 2b are connected to the three-way valve Va via the pipe 5c, and two of the refrigeration units 2c and 2d are three-way via the other pipe 5c. Connected to the valve Vb. Further, the two-way valve Vc may be disposed on the hydrogen gas cooling heat exchanger 3 side of the connection portion of the pipe 5f in the pipe 5e instead of the pipe 5d. In this case, in the hydrogen gas cooling device 1 of this example, the two-way valve Vc adjusts the supply amount of the brine cooled by each refrigeration unit 2 to the hydrogen gas cooling heat exchanger 3 according to the control of the control unit 7. The three-way valves Va and Vb return the brine return amount to the brine tank 4 according to the control of the control unit 7 (directly flow from each refrigeration unit 2 to the brine tank 4 without passing through the hydrogen gas cooling heat exchanger 3. A configuration for adjusting the amount of brine) is employed.

  The liquid feed pumps 6a and 6b (hereinafter also referred to as “liquid feed pump 6” when not distinguished) are examples of “a plurality of liquid feed pumps”, and are respectively disposed in the above-described pipes 5a in the brine pipe 5. The liquid feed pump 6a liquid feeds (pressure feed) the brine from the brine tank 4 to the refrigeration units 2a, 2b, and the liquid feed pump 6b liquid feeds (pressure feed) the brine from the brine tank 4 to the refrigeration units 2c, 2d. Are connected to a plurality of different refrigeration units via a liquid medium pipe ”, and the brine is fed to the four refrigeration units 2 by the two liquid feed pumps 6. Configuration example). In this case, in the hydrogen gas cooling device 1 of this example, as described above, the “brine flow path (heat medium liquid circulation path)” formed by the pipes 5a to 5f of the brine pipe 5 is a closed flow path. The brine is pumped (supplied) from each refrigeration unit 2 to the heat exchanger 3 for cooling hydrogen gas (or the brine tank 4) by the pressure at which the brine is fed from the brine tank 4 to each refrigeration unit 2 by the liquid feed pump 6. The brine is pumped (recovered) from the hydrogen gas cooling heat exchanger 3 to the brine tank 4.

  The control unit 7 is an example of a “control unit”, and comprehensively controls the hydrogen gas cooling device 1. Specifically, the control unit 7 controls the both liquid feeding pumps 6 to feed the brine from the brine tank 4 to each refrigeration unit 2. In this case, as will be described later, the control unit 7 determines that “the inlet side refrigerant temperature and the outlet side refrigerant temperature of the evaporator 24 are The process of specifying the temperature difference (the refrigerant superheat degree in the evaporator 24: hereinafter, this temperature difference is also referred to as “refrigerant superheat degree”) is continuously executed. Further, the control unit 7 specifies the operation state of each refrigeration unit 2 based on the specified refrigerant superheat degree, and specifies the specified operation state, the presence or absence of an air supply start signal from the gas station side equipment X, and the operation state. Depending on the number of the liquid feed pumps 6, each liquid feed pump 6 is in a “continuous operation state (state in which brine is continuously fed)” and “intermittent operation state (state in which brine is intermittently fed)”. Move to one.

  In addition, the control unit 7 determines that the temperature of the brine in the brine tank 4 specified based on the sensor signal S4a from the temperature sensor 4a is, for example, a temperature within a range of −52 ° C. to −55 ° C. Refrigeration capacity of the high-temperature side refrigeration circuit 10 by controlling the compressors 11, 21, electromagnetic valves 13 a, 15 a and electronic expansion valves 13 b, 15 b in each refrigeration unit 2. The refrigeration capacity adjustment process for adjusting the refrigeration capacity of the low temperature side refrigeration circuit 20 is continuously executed. Further, the control unit 7 controls the three-way valves Va and Vb and the two-way valve Vc according to the temperature of the brine in the hydrogen gas cooling heat exchanger 3 specified based on the sensor signal S3a from the temperature sensor 3a. The brine cooled by each refrigeration unit 2 is caused to flow into the hydrogen gas cooling heat exchanger 3 and the brine tank 4.

  In this hydrogen gas cooling device 1, for example, when the hydrogen gas cooling device 1 is activated prior to opening a gas station where the gas station side equipment X and the hydrogen gas cooling device 1 are installed, the control unit 7 Each refrigeration unit 2 is controlled to start the brine cooling process, and both liquid feed pumps 6 are controlled to start the brine feed from the brine tank 4 to each refrigeration unit 2. At this time, the controller 7 operates all of the four refrigeration units 2 and the two liquid feed pumps 6 when the hydrogen gas cooling device 1 is started. In response to this, in each refrigeration unit 2, the refrigerant compression process is started by the compressor 11 of the high temperature side refrigeration circuit 10 and the compressor 21 of the low temperature side refrigeration circuit 20, and from the brine tank 4 via the pipe 5 a. Brine is supplied to the refrigeration unit 2. Further, the control unit 7 specifies the temperature of the brine in the hydrogen gas cooling heat exchanger 3 to control the three-way valves Va and Vb and the two-way valve Vc, and specifies the temperature of the brine in the brine tank 4 Then, the process of controlling the operating state of each refrigeration unit 2 is started.

  Specifically, the control unit 7 specifies the temperature of the brine in the hydrogen gas cooling heat exchanger 3 based on the sensor signal S3a from the temperature sensor 3a immediately after the hydrogen gas cooling device 1 is started. Is executed continuously. In addition, the control unit 7 performs a three-way valve until the cooling process by each refrigeration unit 2 proceeds as described later, and as an example, the temperature of the brine specified based on the sensor signal S3a falls below −38 ° C. Va and Vb are controlled to guide all of the brine flowing out from each refrigeration unit 2 to the pipe 5c to the pipe 5d, and the two-way valve Vc is controlled to 100%. As a result, all of the brine fed by the liquid feed pump 6 and cooled by the refrigeration unit 2 is supplied to the hydrogen gas cooling heat exchanger 3.

  Further, as will be described later, the temperature of the brine supplied to the heat exchanger 3 for cooling the hydrogen gas is lowered by the cooling of the brine by each refrigeration unit 2, and the control unit 7 is specified based on the sensor signal S3a. For example, 5% of the brine flowing out from each refrigeration unit 2 to the pipe 5c is guided to the pipe 5d by controlling the three-way valves Va and Vb. The supply of brine to the heat exchanger 3 for cooling the hydrogen gas is reduced by guiding 95% to the pipe 5f and reducing the opening ratio of the two-way valve Vc. As a result, as will be described later, most of the brine cooled by each refrigeration unit 2 is recovered in the brine tank 4 via the pipes 5f and 5e, and only a small amount of brine is supplied to the hydrogen gas cooling heat via the pipe 5d. It will be in the state supplied to the exchanger 3, and the supercooling of the heat exchanger 3 for hydrogen gas cooling is avoided.

  In this state, a very small amount of brine is continuously supplied into the pipe 5d, the hydrogen gas cooling heat exchanger 3 and the pipe 5e, so that each refrigeration unit 2 passes through the hydrogen gas cooling heat exchanger 3. It is avoided that the temperature of the brine flow path leading to the brine tank 4 is excessively increased due to outside air or geothermal heat. Further, most of the brine cooled by each refrigeration unit 2 flows into the brine tank 4 without passing through the hydrogen gas cooling heat exchanger 3 and is circulated between the refrigeration unit 2 and the brine tank 4. Therefore, the temperature of the brine in the brine tank 4 can be suitably lowered in a short time.

  Further, the control unit 7, for example, cools a large amount of hydrogen gas in the hydrogen gas cooling heat exchanger 3 to increase the temperature of the brine, and the hydrogen gas cooling heat exchanger 3 specified based on the sensor signal S3a. When the temperature of the brine in the inside rises to a temperature exceeding −35 ° C. as an example, the three-way valves Va and Vb are controlled to guide all of the brine that has flowed out of each refrigeration unit 2 to the pipe 5c to the pipe 5d. The supply of brine to the heat exchanger 3 for cooling the hydrogen gas is increased by increasing the opening ratio of the two-way valve Vc. Thereby, as will be described later, most of the brine cooled by each refrigeration unit 2 is supplied to the hydrogen gas cooling heat exchanger 3 via the pipe 5d (a sufficient amount of low temperature necessary for cooling the hydrogen gas). In a state where the brine is supplied to the heat exchanger 3 for cooling hydrogen gas).

  As described above, the control unit 7 specifies the temperature of the brine in the hydrogen gas cooling heat exchanger 3 based on the sensor signal S3a from the temperature sensor 3a, and the three-way valves Va and Vb and the two-way valves according to the specified result. The temperature of the brine in the heat exchanger 3 for cooling the hydrogen gas by continuously performing the process of controlling Vc (adjustment of the amount of brine supplied from each refrigeration unit 2 to the heat exchanger 3 for cooling the hydrogen gas 3) However, while maintaining the temperature within the range of −33 ° C. to −40 ° C. suitable for cooling of hydrogen gas, the situation where the piping in the heat exchanger 3 for cooling the hydrogen gas is overcooled and deteriorated is avoided. .

  Further, the control unit 7 monitors the temperature of the brine in the heat exchanger 3 for cooling the hydrogen gas and controls the three-way valves Va and Vb and the two-way valve Vc in parallel with the sensor signal S4a from the temperature sensor 4a. Based on this, the temperature of the brine in the brine tank 4 is specified, and the process of controlling the operating state of each refrigeration unit 2 according to the specified temperature is continuously executed. In the hydrogen gas cooling device 1 of this example, the inlet side refrigerant temperature of the evaporator 24 is controlled in parallel with the opening / closing control of the three-way valves Va, Vb and the two-way valve Vc and the control of the operation state of each refrigeration unit 2. A process for controlling the operation state of both liquid feed pumps 6 is executed according to the temperature difference from the outlet side refrigerant temperature. In order to facilitate understanding of the cooling process of the brine by each refrigeration unit 2, both liquid feeds are performed. The control of the operation state of the pump 6 will be described in detail later.

  In this case, when the hydrogen gas cooling device 1 has been stopped for a certain long time before the hydrogen gas cooling device 1 is activated, the hydrogen tank cooling device 1 is activated in the brine tank 4 or the brine pipe 5 when the hydrogen gas cooling device 1 is activated. The temperature of the brine is higher than the temperature suitable for cooling the hydrogen gas (for example, about 25 ° C., which is about the same as the outside temperature). When such a high temperature brine is to be cooled by the evaporator 24 of the low temperature side refrigeration circuit 20 in the refrigeration unit 2 (when the low temperature side refrigeration circuit 20 is operated in a state where the high temperature brine is being fed). As a result, the amount of refrigerant vaporized in the evaporator 24 increases and the refrigerant pressure in the low-temperature side refrigeration circuit 20 becomes excessively high. In such a state, the compressor 21 is subjected to a heavy burden, which may lead to a decrease in the service life thereof, and also a low temperature side refrigeration circuit in order to avoid damage to the compressor 21 due to an increase in refrigerant pressure. 20 may need to be stopped urgently and the brine may not be cooled. Further, the low temperature side refrigeration circuit 20 for cooling the brine to an extremely low temperature is difficult to lower the temperature of the high temperature brine in a short time. It takes a long time to cool down.

  Therefore, in the hydrogen gas cooling device 1 of this example, the controller 7 specifies the temperature of the brine in the brine tank 4 based on the sensor signal S4a from the temperature sensor 4a installed in the brine tank 4, and the specified temperature Accordingly, by changing the operation state of each refrigeration unit 2 according to the above, a configuration is adopted in which the temperature of the high-temperature brine is lowered in a short time without causing the low-temperature side refrigeration circuit 20 to be in a high load state. Specifically, the control unit 7 continuously executes one of the following “Process A” and “Process B” as the “refrigeration capacity adjustment process” according to the temperature of the brine in the brine tank 4.

  More specifically, the control unit 7 determines the temperature of the brine in the brine tank 4 specified based on the sensor signal S4a from the temperature sensor 4a (“the heat transfer liquid at a predetermined position in the heat transfer liquid circulation path”). As an example, when the condition that the temperature is −33 ° C. or more (an example of “condition A”) is satisfied, the brine by the low temperature side refrigeration circuit 20 (evaporator 24) Without performing the cooling, the “processing A” is performed in which the brine is cooled by the high temperature side refrigeration circuit 10 (evaporator 16). Further, when the condition that the temperature of the brine in the brine tank 4 specified based on the sensor signal S4a is lower than −33 ° C. (an example of “condition B”) is satisfied. Then, the solenoid valves 13a and 15a and the electronic expansion valves 13b and 15b are controlled so that the amount of refrigerant supplied to the evaporator 14 is increased as compared with the time of execution of the “Process A”, and the evaporator 14 causes the low temperature side refrigeration circuit 20 "Process B" is performed in which the brine is cooled by the low-temperature side refrigeration circuit 20 (evaporator 24) while the condenser 22 is being cooled.

  At this time, in the present example in which the temperature of the brine is about 25 ° C. due to the fact that it is immediately after starting after a long-time stop state, it is specified based on the sensor signal S3a from the temperature sensor 3a. Since the temperature of the brine is high, both the three-way valves Va and Vb are controlled to connect each pipe 5c to the pipe 5d, and the two-way valve Vc is controlled to 100% opening ratio, A circulation path that circulates through each refrigeration unit 2 and the heat exchanger 3 for cooling hydrogen gas in this order is formed. Thereby, after the brine supplied to each refrigeration unit 2 from the brine tank 4 via the pipes 5a by the both liquid feed pumps 6 is supplied to the hydrogen gas cooling heat exchanger 3 via the pipes 5c and 5d. Then, the state is recovered into the brine tank 4 through the pipe 5e.

  Further, since the temperature of the brine in the brine tank 4 specified based on the temperature sensor 4a is also high, the control unit 7 executes the above-mentioned “Process A”. Note that at this point in time when all the four refrigeration units 2 are operating immediately after startup, the control unit 7 executes the following control in parallel for all the four refrigeration units 2. To do.

  Specifically, the control unit 7 first reduces the refrigerant discharge amount to the evaporator 24 by controlling the electronic expansion valve 23 to reduce the opening degree. As a result, the cooling of the brine by the low temperature side refrigeration circuit 20 is substantially stopped, and the amount of refrigerant vaporized in the evaporator 24 even when the high temperature brine is supplied to the evaporator 24 via the pipes 5a and 5b. Is excessively increased (a situation in which the refrigerant pressure in the low temperature side refrigeration circuit 20 is excessively high) is avoided. Further, the control unit 7 controls the electromagnetic valve 13a to block the passage of refrigerant from the condenser 12 to the electronic expansion valve 13b (evaporator 14), and also controls the electromagnetic valve 15a to electronically expand from the condenser 12. The refrigerant is allowed to pass through the valve 15b (evaporator 16). Thereby, as a result of the refrigerant condensed in the condenser 12 being supplied to the evaporator 16 via the electronic expansion valve 15b, the brine supplied to the evaporator 16 via the pipe 5a is suitably cooled in the evaporator 16. The

  Moreover, although the brine cooled in the evaporator 16 is supplied to the evaporator 24 via the pipe 5b, the opening degree of the electronic expansion valve 23 is reduced, and the refrigerant discharge amount to the evaporator 24 is reduced. Therefore, the inside of the brine tank 4 is hardly cooled by the evaporator 24 via the pipe 5c, the three-way valve Va (or the three-way valve Vb), the pipe 5d, the hydrogen gas cooling heat exchanger 3 and the pipe 5e. To be recovered. Further, the brine collected in the brine tank 4 is supplied again to each refrigeration unit 2 by the liquid feed pump 6. Further, the control unit 7 performs the above-mentioned “Processing A” until the temperature of the brine in the brine tank 4 specified based on the sensor signal S4a falls below −33 ° C. (while “Condition A” is satisfied). Continue to run. Thereby, the temperature of the brine circulated between the brine tank 4 and each refrigeration unit 2 gradually decreases.

  Further, by continuing the above “Processing A”, when the temperature of the brine in the brine tank 4 specified based on the sensor signal S4a from the temperature sensor 4a falls below −33 ° C., the control unit 7 , “Process B” is executed assuming that “Condition B” is satisfied. Specifically, the control unit 7 connects the pipes 5c to the pipes 5d by both the three-way valves Va and Vb, and maintains the state in which the two-way valve Vc is controlled to an opening ratio of 100%, while maintaining the electromagnetic valve 15a. Is controlled to block the passage of refrigerant from the condenser 12 to the electronic expansion valve 15b (evaporator 16), and the electromagnetic valve 13a is controlled to refrigerant from the condenser 12 to the electronic expansion valve 13b (evaporator 14). Is allowed to pass. Thereby, as a result of the refrigerant condensed in the condenser 12 being supplied to the evaporator 14 via the electronic expansion valve 13b, the condenser 22 integrated with the evaporator 14 is suitably cooled by the evaporator 14, A sufficient amount of refrigerant required to cool the brine in the low temperature side refrigeration circuit 20 (evaporator 24) is condensed in the condenser 22.

  In addition, the control unit 7 controls the electronic expansion valve 23 to increase the opening, thereby increasing the refrigerant discharge amount to the evaporator 24. As a result, the brine supplied from the brine tank 4 to the evaporator 24 via the pipe 5a, the evaporator 16 and the pipe 5b is sufficiently cooled by heat exchange with the refrigerant in the evaporator 24, and the pipe 5c, the three-way valve It is recovered in the brine tank 4 through Va (or the three-way valve Vb), the pipe 5d, the hydrogen gas cooling heat exchanger 3 and the pipe 5e. In this case, in the hydrogen gas cooling device 1 of the present example, the “process for cooling the brine by the evaporator 16 of the high-temperature side refrigeration circuit 10” is performed before the “process B” for cooling the brine by the evaporator 24 of the low-temperature side refrigeration circuit 20. A ”is executed, and the temperature of the brine supplied to the evaporator 24 in“ Process B ”is sufficiently low below −33 ° C. Therefore, the brine can be suitably cooled without causing a situation in which the amount of refrigerant vaporized in the evaporator 24 becomes excessively high and the refrigerant pressure in the low temperature side refrigeration circuit 20 becomes excessively high.

  In addition, when the temperature of the brine in the heat exchanger 3 for cooling the hydrogen gas specified based on the sensor signal S3a from the temperature sensor 3a is lowered to -38 ° C., the control unit 9 connects the piping from each refrigeration unit 2 to the piping. For example, 5% of the brine flowing out to 5c is guided to the pipe 5d, the remaining 95% is guided to the pipe 5f, and the opening ratio of the two-way valve Vc is reduced. At this time, a circulation path through which the brine circulates is formed between the brine tank 4 and the refrigeration unit 2, and is supplied from the brine tank 4 to the refrigeration unit 2 via the pipe 5a by the liquid feed pump 6 and flows into the pipe 5c. Most of the brine flows into the pipe 5e via the pipe 5f without being supplied to the hydrogen gas cooling heat exchanger 3, and is recovered in the brine tank 4. Thereafter, by continuously executing “Process B”, the brine is sufficiently cooled so that the temperature of the brine in the brine tank 4 is about −55 ° C.

  Regarding the control of the high temperature side refrigeration circuit 10 in “Process B”, the supply of the refrigerant to the evaporator 16 corresponding to the “third evaporator” is stopped and the evaporation corresponding to the “first evaporator” is performed. By starting the supply of the refrigerant to the evaporator 14, not only the above control method of cooling the condenser 22 by the evaporator 14 without cooling the brine by the evaporator 16, but also after starting “Process B”. When the temperature of the brine is higher than the lower limit of the coolable temperature of the high-temperature side refrigeration circuit 10 (for example, when the brine temperature is −40 ° C. or higher), A method of cooling the condenser 22 by the evaporator 14 while continuing cooling of the brine by the evaporator 16 by reducing the supply amount and starting the supply of the refrigerant to the evaporator 14 may be adopted. That.

  On the other hand, when the cooling process of the brine by each refrigeration unit 2 is continued and the temperature of the brine in the brine tank 4 specified based on the sensor signal S4a from the temperature sensor 4a falls below −55 ° C., the control unit 7 is specified based on the sensor signal S4a when a predetermined time (several tens to hundreds of seconds: 300 seconds as an example) has elapsed since the time when the brine temperature was determined to be −55 ° C. It is determined whether or not the temperature of the brine in the brine tank 4 is maintained at a temperature lower than −55 ° C. At this time, as described later, when the hydrogen gas is not cooled by the hydrogen gas cooling heat exchanger 3 and the brine in the brine tank 4 is maintained at a temperature lower than −55 ° C., the control unit 7 Then, one of the operating refrigeration units 2 is stopped.

  Specifically, in the present example in which the four refrigeration units 2a to 2d are operated, the control is performed when the state where the temperature of the brine in the brine tank 4 is lower than -55 ° C is maintained for 300 seconds. As an example, the unit 7 executes a process of stopping the refrigeration unit 2b (a process of stopping the high temperature side refrigeration circuit 10 and the low temperature side refrigeration circuit 20 of the refrigeration unit 2b). At this time, the brine fed from the brine tank 4 by the liquid feed pump 6a is passed through the stopped refrigeration unit 2b, but the hydrogen gas is not cooled in the hydrogen gas cooling heat exchanger 3. Since the cooling is continuously performed by the refrigeration units 2a, 2c, and 2d in operation, the brine in the brine tank 4 is maintained at a temperature lower than −55 ° C. Thereby, the energy consumed by the hydrogen gas cooling device 1 is reduced by the amount of stopping the refrigeration unit 2b without causing a situation in which the temperature of the brine in the brine tank 4 or the brine pipe 5 rises.

  Further, the control unit 7 determines the brine tank based on the sensor signal S4a when a predetermined time (300 seconds in this example) elapses from the time when the refrigeration unit 2b is stopped as described above. It is determined again whether or not the temperature of the brine in 4 is maintained at a temperature lower than -55 ° C. At this time, when the brine in the brine tank 4 is maintained at a temperature lower than −55 ° C., the control unit 7 selects one of the operating refrigeration units 2a, 2c, and 2d (as an example, a refrigeration unit). Unit 2a) is stopped. At this time, since the cooling process of the brine by the refrigeration units 2c and 2d is continued, the refrigeration unit 2a is stopped without causing a situation in which the temperature of the brine in the brine tank 4 or the brine pipe 5 rises. Therefore, the energy consumed by the hydrogen gas cooling device 1 is further reduced.

  Further, the control unit 7 determines the brine tank based on the sensor signal S4a when a predetermined time (300 seconds in this example) has elapsed since the time when the refrigeration unit 2a was stopped as described above. It is determined again whether or not the temperature of the brine in 4 is maintained at a temperature lower than -55 ° C. At this time, when the brine in the brine tank 4 is maintained at a temperature lower than −55 ° C., the control unit 7 selects one of the operating refrigeration units 2c and 2d (for example, the refrigeration unit 2d). ). At this time, since the cooling process of the brine by the refrigeration unit 2c is continued, the amount of the refrigeration unit 2d stopped without causing a situation in which the temperature of the brine in the brine tank 4 or the brine pipe 5 rises. The energy consumed by the hydrogen gas cooling device 1 is further reduced.

  In addition, the control unit 7 determines the brine tank based on the sensor signal S4a when a predetermined time (300 seconds in this example) has elapsed since the time when the refrigeration unit 2d was stopped as described above. It is determined again whether or not the temperature of the brine in 4 is maintained at a temperature lower than -55 ° C. At this time, even if the control unit 7 maintains the temperature of the brine in the brine tank 4 below −55 ° C., only one of the refrigeration units 2c is operating, and the other refrigeration units 2a, 2b, 2d Because of the stopped state, the operated state is maintained without stopping the operating refrigeration unit 2c. As a result, since the cooling of the brine is continued by the refrigeration unit 2c that is kept in operation, the brine in the brine tank 4 and the brine pipe 5 keeps −55 ° C. even in summer when the ambient temperature becomes high. Maintained below cryogenic temperatures. Further, by stopping three of the refrigeration units 2a, 2b, and 2d among the refrigeration units 2a to 2d, energy consumption by the hydrogen gas cooling device 1 is sufficiently reduced.

  On the other hand, when filling an automobile such as a hydrogen fuel cell vehicle with hydrogen gas at the gas station, as an example, an air supply start signal is output from the gas station side equipment X to the control unit 7 of the hydrogen gas cooling device 1. Accordingly, the control unit 7 starts the hydrogen gas cooling process in the hydrogen gas cooling heat exchanger 3. In the following description, as an example, the gas station-side equipment X in a state where the three refrigeration units 2a, 2b, and 2d are stopped and only the refrigeration unit 2c is operated to cool the brine. It is assumed that an air supply start signal is output from. At this time, the control unit 7 first controls the three-way valves Va and Vb to guide all of the brine flowing out from the respective refrigeration units 2 to the pipe 5c to the pipe 5d, and also controls the two-way valve Vc to open. Increase the rate. As a result, the cryogenic brine stored in the brine tank 4 passes through each refrigeration unit and is supplied to the heat exchanger 3 for cooling the hydrogen gas.

  Further, in the gas station side equipment X, hydrogen gas is supplied from the gas tank Xa to the dispenser Xb via the gas pipe Xc, and the fuel tank (gas tank: vehicle side tank) of the automobile is filled from the dispenser Xb. At this time, when the hydrogen gas is passed through the heat exchanger 3 for cooling the hydrogen gas, the hydrogen gas is cooled by being subjected to heat exchange with the cryogenic brine supplied to the heat exchanger 3 for cooling the hydrogen gas via the pipe 5d. Therefore, as a result of filling the vehicle side tank with hydrogen gas (hydrogen gas at −33 ° C. to −40 ° C.) whose temperature has been sufficiently lowered, the charging efficiency can be sufficiently improved.

  Further, the brine whose temperature has been increased by cooling the hydrogen gas in the heat exchanger 3 for cooling the hydrogen gas is recovered in the brine tank 4 through the pipe 5e. For this reason, at the time of cooling of hydrogen gas, the temperature of the brine in the brine tank 4 rises because the brine whose temperature has risen flows. Therefore, when the temperature of the brine in the brine tank 4 specified based on the sensor signal S4a from the temperature sensor 4a exceeds −52 ° C., which is an example of “predetermined temperature”, the control unit 7 As an example, all the frozen units 2a, 2b, and 2d in the stopped state are restarted.

  Specifically, the control unit 7 controls the refrigeration units 2a, 2b, and 2d in the stopped state to start the refrigerant compression process by the compressor 11 of the high temperature side refrigeration circuit 10 and the compressor 21 of the low temperature side refrigeration circuit 20. In addition, regardless of the temperature of the brine in the brine tank 4, the brine is cooled by the high temperature side refrigeration circuit 10 (evaporator 16) without cooling the brine by the low temperature side refrigeration circuit 20 (evaporator 24). A ”is executed. Further, the control unit 7 is a temperature sensor installed in the brine tank 4 when a predetermined time (for example, 300 seconds) has elapsed since the operation of the refrigeration units 2a, 2b, and 2d has started. The temperature of the brine in the brine tank 4 is specified based on the sensor signal S4a from 4a.

  At this time, for example, by cooling a large amount of hydrogen gas in the heat exchanger 3 for cooling hydrogen gas, high-temperature brine is recovered in the brine tank 4, and the temperature of the brine specified based on the sensor signal S4a is −33. When the “condition A” that the temperature is equal to or higher than “° C.” is satisfied, the control unit 7 continues to execute the “processing A”, and the brine in the brine tank 4 based on the sensor signal S4a. Continue monitoring the temperature.

  On the other hand, the temperature of the brine in the brine tank 4 specified based on the sensor signal S4a is lower than −33 ° C. when a predetermined time has elapsed since the operation of the refrigeration units 2a, 2b, and 2d has started. When the temperature of the brine in the brine tank 4 specified based on the sensor signal S4a by continuing “Processing A” as described above falls below −33 ° C., the control unit 7 B ”is satisfied, the electromagnetic valves 13a and 15a and the electronic expansion valves 13b and 15b are controlled to increase the amount of refrigerant supplied to the evaporator 14, and the evaporator 14 uses the condenser of the low temperature side refrigeration circuit 20 to increase the refrigerant supply amount. The refrigeration units 2a, 2b, and 2d are caused to execute “Process B” in which the brine is cooled by the low-temperature side refrigeration circuit 20 (evaporator 24) while cooling the cooling unit 22.

  As a result, the brine whose temperature has risen due to the cooling of the hydrogen gas in the heat exchanger 3 for cooling the hydrogen gas is sufficiently cooled to an extremely low temperature below -33 ° C., and the operation is continued without being stopped. In the brine tank 4 by the four units of the refrigeration unit 2c that executes the “process A” and the “refrigeration units 2a, 2b, and 2d that have been restarted from the stopped state and execute the“ process B ”. Each of the “processing B” is executed until the brine temperature of −55 ° C. falls below −55 ° C. As a result, since the cryogenic brine suitable for cooling the hydrogen gas is continuously supplied to the hydrogen gas cooling heat exchanger 3 that is cooling the hydrogen gas, the temperature of −33 ° C. to −40 ° C. A state in which the hydrogen gas can be sufficiently cooled to a temperature within the range is maintained.

  When the filling of hydrogen gas into the automobile (vehicle side tank) is completed, an air supply end signal is output from the gas station side equipment X to the control unit 7 of the hydrogen gas cooling device 1. At this time, the control unit 7 that has determined that the cooling of the hydrogen gas has been completed specifies the temperature of the brine in the heat exchanger 3 for cooling the hydrogen gas based on the sensor signal S3a from the temperature sensor 3a, and the specified temperature Accordingly, the process for controlling the three-way valves Va and Vb and the two-way valve Vc is executed as described above. Further, the control unit 7 specifies the temperature of the brine in the brine tank 4 based on the sensor signal S4a from the temperature sensor 4a, and changes the operation state of each refrigeration unit 2 based on the specified temperature (“Process” A ”,“ Process B ”, and transition to the stop state). Thereby, when the state where the cooling of the hydrogen gas is not performed continues, the state in which the temperature of the brine in the brine tank 4 is kept below −55 ° C. is maintained until only the refrigeration unit 2 c is in operation. The operating refrigeration units 2 are stopped one by one.

  On the other hand, as described above, in the hydrogen gas cooling device 1 of this example, the control unit 7 controls the three-way valves Va and Vb and the two-way valve Vc in accordance with the temperature of the brine in the hydrogen gas cooling heat exchanger 3. In parallel with the control of the operation state of each refrigeration unit 2 according to the temperature of the brine in the brine tank 4, the temperature difference between the inlet side refrigerant temperature and the outlet side refrigerant temperature of the evaporator 24 of each refrigeration unit 2 ( According to the refrigerant superheat degree in the evaporator 24) and the number of the liquid feed pumps 6 in the operating state, the control for shifting both the liquid feed pumps 6 to the “continuous operation state” and the “intermittent operation state” is continuously executed. As a result, the refrigerant pressure in the low-temperature side refrigeration circuit 20 of each refrigeration unit 2 becomes excessively high (the low-temperature side refrigeration circuit 20 is in a high load state) without incurring a situation where the refrigerant pressure is increased. Suitable for cooling hydrogen gas Configured into a state capable of providing a sufficient amount of brine is employed.

  Specifically, the control unit 7 specifies the “inlet-side refrigerant temperature” of the evaporator 24 based on the sensor signal S24a from the temperature sensor 24a of each refrigeration unit 2 immediately after the hydrogen gas cooling device 1 is activated. The process of specifying the “exit-side refrigerant temperature” of the evaporator 24 based on the sensor signal S24b from the temperature sensor 24b, and the “temperature between the inlet-side refrigerant temperature and the outlet-side refrigerant temperature” based on both specified temperatures. The process of calculating the “difference (refrigerant superheat degree in the evaporator 24)” is continuously executed, and the liquid feed pumps 6a and 6b are controlled according to the specified refrigerant superheat degree.

  In this case, in the hydrogen gas cooling device 1 of this example, at least one liquid feed pump 6 is moved to the “continuous operation state” without being cooled in the hydrogen gas cooling heat exchanger 3 and operated. In the heat exchanger 3 for cooling hydrogen gas, both the liquid feed pumps 6a and 6b are shifted to the “continuous operation state” (an example of “a state where two or more liquid feed pumps are operating”). An example of the “second temperature preliminarily defined” is the refrigerant superheat degree in the evaporator 24 of each refrigeration unit 2 connected to the operating liquid feed pump 6 in any state where the hydrogen gas is being cooled. The “second condition” that the temperature becomes 15 ° C. or higher (that is, the vaporization amount of the refrigerant in the evaporator 24 may increase excessively) is any of the refrigeration units 2. When satisfied in Control unit 7 shifts the liquid feed pump 6 connected to the refrigeration unit 2 only one is stopped in the "intermittent operation state".

  As a result, the brine is intermittently fed to the evaporator 24 having a refrigerant superheat degree of 15 ° C. or higher (a state in which the amount of liquid fed per unit time to the evaporator 24 is reduced). As a result of the decrease in the amount of refrigerant vaporized in the evaporator 24 of the refrigeration unit 2 in which the brine is liquid-fed by the liquid feed pump 6 shifted to the “intermittent operation state”, the refrigerant pressure in the low-temperature refrigeration circuit 20 is excessive The situation of becoming high is avoided.

  Moreover, in the hydrogen gas cooling device 1 of this example, the refrigeration unit connected to the liquid feed pump 6a regardless of whether or not the control unit 7 is cooling the hydrogen gas in the hydrogen gas cooling heat exchanger 3. In both 2a and 2b, the superheat degree of the refrigerant in the evaporator 24 becomes a temperature of 5 ° C. or less, which is an example of the “predetermined first temperature” (that is, the amount of refrigerant vaporized in the evaporator 24 is excessive). When the “first condition” is satisfied, the liquid feed pump 6a is operated to shift to the “continuous operation state”. In both the refrigeration units 2c and 2d connected to the liquid feed pump 6b, when the “first condition” that the refrigerant superheat degree in the evaporator 24 reaches a temperature of 5 ° C. or less is satisfied, the liquid feed pump 6b Work It is shifted to the "continuous operation state" Te.

  Thereby, the brine can be suitably cooled by the refrigeration unit 2 without causing a situation in which the refrigeration unit 2 connected to the liquid feed pump 6 shifted to the “continuous operation state” is in a high load state. As a result, when the temperature of the brine in the heat exchanger 3 for cooling the hydrogen gas is −38 ° C. or more, the sufficiently cooled brine can be supplied to the heat exchanger 3 for cooling the hydrogen gas. When the temperature of the brine in the heat exchanger 3 falls below −38 ° C., the brine is circulated between the refrigeration unit 2 and the brine tank 4 so that the temperature of the brine in the brine tank 4 becomes about −55 ° C. be able to.

  In this case, in the hydrogen gas cooling device 1 of this example, the above-mentioned “processing A” is executed in one of the refrigeration units 2a and 2b connected to the liquid feed pump 6a, and the other of the refrigeration units 2a and 2b. In the state where the above-mentioned “processing B” is being performed, the control unit 7 “continues” the liquid feed pump 6a according to the refrigerant superheat degree of the evaporator 24 in the refrigeration unit 2 that is performing “processing B”. It is determined whether to shift to “operation state” or “intermittent operation state”. Further, the above-mentioned “Process A” is executed in one of the refrigeration units 2c, 2d connected to the liquid feed pump 6b, and the “Process B” is executed in the other of the refrigeration units 2c, 2d. In the state where the control unit 7 is in the “continuous operation state” or “intermittent operation state”, the control unit 7 controls the liquid feed pump 6b according to the refrigerant superheat degree of the evaporator 24 in the refrigeration unit 2 executing “processing B”. Decide whether to move to.

  Thereby, in the state where the refrigerant superheat degree in the evaporator 24 of the refrigeration unit 2 that is executing “Processing B” is 15 ° C. or more, the liquid feed pump 6 connected to the refrigeration unit 2 is in the “intermittent operation state”. As a result, the situation where the high temperature brine is supplied to the refrigeration unit 2 and the low temperature side refrigeration circuit 20 is in a high load state is avoided, and the refrigeration unit 2 that is executing “Process B” In the state where the refrigerant superheat degree in the evaporator 24 is 5 ° C. or lower, the liquid feed pump 6 connected to the refrigeration unit 2 is shifted to the “continuous operation state”, so that the refrigeration unit 2 is supplied. The brine is sufficiently cooled to cryogenic temperature.

  Further, in the hydrogen gas cooling device 1 of this example, either one of the liquid feed pumps 6a and 6b is shifted to the “continuous operation state” and the other is shifted to the “intermittent operation state” (“the liquid feed pump is turned on”). An example of a state in which “only one unit is operated”) Either of the refrigeration units 2 connected to the liquid feed pump 6 in operation in the state where the hydrogen gas cooling heat exchanger 3 cools the hydrogen gas. When the above “second condition” is satisfied, the control unit 7 maintains the operating state without stopping the liquid feed pump 6 in operation. Accordingly, it is necessary for cooling the hydrogen gas to the hydrogen gas cooling heat exchanger 3 without causing a situation in which brine is not supplied to the hydrogen gas cooling heat exchanger 3 that is cooling the hydrogen gas. It is possible to continuously supply a sufficient amount of brine.

  Note that the degree of refrigerant superheating in the evaporator 24 of each refrigeration unit 2 sequentially changes depending on the operating state of the refrigeration unit 2 and the temperature of the brine supplied to the refrigeration unit 2. Specifically, for example, immediately after the hydrogen gas cooling device 1 is started, “Processing A” is executed as described above, and the cooling of the brine is not performed in the refrigeration unit 2 by the low temperature side refrigeration circuit 20 (evaporator 24). When the brine is cooled by the high temperature side refrigeration circuit 10 (evaporator 16), the low temperature side refrigeration circuit 20 is not substantially functioning, so that the refrigerant superheat degree in the evaporator 24 is 5 ° C. or less. . Therefore, the control unit 7 determines that the “first condition” is satisfied.

  Further, by continuously executing “Processing A”, the temperature of the brine in the brine tank 4 specified based on the sensor signal S4a from the temperature sensor 4a is lowered. B ”is executed, and immediately after the cooling of the brine by the low temperature side refrigeration circuit 20 (evaporator 24) is started in the refrigeration unit 2, the brine fed to the low temperature side refrigeration circuit 20 (evaporator 24) Since the temperature is not sufficiently lowered, the refrigerant superheat degree in the evaporator 24 becomes 15 ° C. or higher. Therefore, the control unit 7 determines that the “second condition” is satisfied.

  Further, by continuously executing “Process B”, the temperature of the brine in the brine tank 4 specified based on the sensor signal S4a from the temperature sensor 4a is reduced to some extent, and the amount of refrigerant vaporized in the evaporator 24 Becomes a state in which the refrigerant pressure does not increase excessively (a state in which the refrigerant pressure in the low temperature side refrigeration circuit 20 does not become excessively high), the refrigerant superheat degree in the evaporator 24 becomes 5 ° C. or less. At this time, the control unit 7 determines that the “first condition” is satisfied.

  Therefore, as described above, control of the three-way valves Va and Vb and the two-way valve Vc according to the temperature of the brine in the hydrogen gas cooling heat exchanger 3 and each refrigeration according to the temperature of the brine in the brine tank 4 are performed. In parallel with the control of the operation state of the unit 2, the degree of refrigerant superheating in the evaporator 24 of each refrigeration unit 2, the number of operating liquid feed pumps 6, and the necessity of cooling of the hydrogen gas in the heat exchanger 3 for cooling the hydrogen gas are determined. Accordingly, by continuously executing the control for changing the operation state of the liquid feed pump 6, it is possible to cool the hydrogen gas without causing the low temperature side refrigeration circuit 20 to be in a high load state in any refrigeration unit 2. When it is necessary to cool the hydrogen gas in the heat exchanger 3, a sufficient amount of brine can be reliably supplied to the heat exchanger 3 for cooling the hydrogen gas.

  Thus, this hydrogen gas cooling device 1 includes a plurality of refrigeration units 2 and a plurality of liquid feed pumps 6, and each liquid feed pump 6 is transferred from the plurality of refrigeration units 2 to the hydrogen gas cooling heat exchanger 3. Each of the liquids is connected to a plurality of different refrigeration units 2 so as to be able to supply brine, and the control unit 7 performs a “refrigeration capacity adjustment process” for adjusting the refrigeration capacity of each refrigeration unit 2. The “first condition” when the refrigerant superheat degree in the evaporator 24 of each refrigeration unit 2 connected to the feed pump 6 is equal to or lower than a predetermined “first temperature (5 ° C. in this example)”. When all the refrigeration units 2 are filled, one of the liquid feed pumps 6 is operated to shift to the “continuous operation state”, and the hydrogen gas cooling heat exchanger 3 does not cool the hydrogen gas. At least Operating either in a state where one liquid feed pump 6 is operating or in a state where two or more liquid feed pumps 6 are operated to cool hydrogen gas in the heat exchanger 3 for cooling hydrogen gas The refrigerant superheat degree in the evaporator 24 of each refrigeration unit 2 connected to any one of the liquid feed pumps 6 is a “second temperature (in this example) that is higher than the“ first temperature ”. , 15 ° C.) ”or more, when the“ second condition ”is satisfied in any of the refrigeration units 2, only one liquid feed pump 6 connected to any of the refrigeration units 2 is provided. The liquid feed pump 6 that is in operation in a state where the hydrogen gas is cooled in the hydrogen gas cooling heat exchanger 3 by stopping and shifting to the “intermittent operation state” and operating only one liquid feed pump 6. Each connected refrigeration unit Maintain the state of operating in the "continuous operation state" without stopping the liquid feed pump 6 during operation when the "second condition" is satisfied in any of the.

  Therefore, according to the hydrogen gas cooling device 1, unlike the “hydrogen gas cooling device” in which brine is supplied to a plurality of “refrigeration units” by one “liquid feed pump”, the brine is suitably used. A situation where brine is supplied to the refrigeration unit 2 that is not in a coolable state or a situation where high temperature brine is supplied to the refrigeration unit 2 in which the low temperature side refrigeration circuit 20 may be overloaded is preferably avoided. In addition, the brine is supplied only to the refrigeration unit 2 in which the low temperature side refrigeration circuit 20 is not likely to be overloaded and can be suitably cooled, and this is suitably cooled. can do. Further, the number of liquid feed pumps 6 constituting the hydrogen gas cooling device 1 is smaller than that of the “hydrogen gas cooling device” having a plurality of “liquid feed pumps” having the same number as the “refrigeration units”. Therefore, the increase in the manufacturing cost of the hydrogen gas cooling device 1 can be sufficiently suppressed. Further, when the hydrogen gas is being cooled in the hydrogen gas cooling heat exchanger 3, a sufficient amount of brine necessary for cooling the hydrogen gas is removed by at least one liquid feed pump 6. Therefore, the hydrogen gas can be reliably cooled in the heat exchanger 3 for cooling the hydrogen gas. When a small amount of brine is supplied to the heat exchanger 3 for cooling the hydrogen gas, the liquid feed pump 6 is stopped by operating a small number of liquid feed pumps 6 to feed a small amount of brine. Energy consumption can be reduced by the amount.

  Further, in the hydrogen gas cooling device 1, the control unit 7 determines that the temperature of the brine at a predetermined position (in the brine tank 4 in this example) is within a predetermined temperature range. “Processing A”, in which the brine is cooled by the evaporator 16 without cooling the brine by the evaporator 24 when the “condition A” is satisfied, is defined in advance. The refrigerant supply amount to the evaporator 14 is controlled by controlling the refrigerant supply amount adjusting valve when “condition B” that the temperature of the brine at the position is lower than a predetermined temperature is substantially satisfied. “Processing B”, in which the condenser 22 is cooled by the evaporator 14 while cooling the condenser 22 by the evaporator 24 and the brine is cooled by the evaporator 24, is executed as the “refrigeration capacity adjustment process”. "Processing A" is executed in the refrigeration unit 2 and "Processing B" is executed in any one of the other refrigeration units 2 connected to the liquid feed pump 6 to which one of the refrigeration units 2 is connected. When one of the other refrigeration units 2 is connected, any one of the refrigeration units 2 and any one of the other refrigeration units 2 is connected to the liquid feed pump 6 based on the degree of refrigerant superheat in the evaporator 24 of the other It is determined whether to shift to “continuous operation state” or “intermittent operation state”.

  Therefore, according to the hydrogen gas cooling device 1, when the temperature of the brine is high, the compressor 21 is damaged by performing “Processing A” in which the cooling of the brine by the low temperature side refrigeration circuit 20 is not performed. In addition, not only can the emergency stop of the low-temperature refrigeration circuit 20 be avoided in order to avoid damage to the compressor 21, but also the brine is cooled by the high-temperature refrigeration circuit 10 having high cooling efficiency of the high-temperature brine. As a result, the temperature of the high-temperature brine is lowered in a short time, and when the temperature of the brine is lowered to a temperature that can be suitably cooled by the low-temperature side refrigeration circuit 20, "Process B" is executed. By cooling, the brine can be cooled to the target temperature, so it is possible to reliably cool the hot brine to the target temperature in a short time. In addition, the degree of refrigerant superheat in the evaporator 24 of the refrigeration unit 2 that is executing “Processing B” among the refrigeration units 2 connected to any one of the liquid feed pumps 6 is equal to or higher than the “first temperature”. Sometimes, the liquid feed pump 6 connected to the refrigeration unit 2 is shifted to the “intermittent operation state” and the supply of brine to the refrigeration unit 2 is stopped. It is possible to reliably avoid the refrigeration circuit 20 from being in a high load state.

  Furthermore, according to the hydrogen gas cooling device 1, the brine recovered from the hydrogen gas cooling heat exchanger 3 is configured to be able to store liquid, and the stored brine is arranged to be supplied to each refrigeration unit 2. By specifying the temperature of the brine specified based on the sensor signal S4a from the temperature sensor 4a disposed in the brine tank 4 as “the temperature of the brine at a predetermined location”, for example, “predetermined location” The temperature of the brine at a position different from “” is monitored, the temperature of the brine at the “predetermined position” is calculated, and “condition A” and “condition B” are determined based on the calculated temperature Unlike the “hydrogen gas cooling device” configured to execute either “Processing A” or “Processing B”, it is specified by the sensor signal S4a from the temperature sensor 4a. Since it is possible to directly determine whether or not “condition A” and “condition B” are satisfied based on the temperature of the brine, “processing A” and “processing B” can be performed without executing complicated calculation processing. The brine can be efficiently cooled by properly performing any one of the above.

  The configuration of the “hydrogen gas cooling device” is not limited to the configuration of the hydrogen gas cooling device 1 described above. For example, the configuration in which brine is fed to two refrigeration units 2 by one liquid feed pump 6 has been described as an example, but brine is fed to three or more refrigeration units 2 by one liquid feed pump 6. It is also possible to adopt a liquid feeding configuration. In the hydrogen gas cooling device 1 described above, when the temperature of the brine cooled by the refrigeration unit 2 is high (when the temperature of the brine in the brine tank 4 is −33 ° C. or higher), the low-temperature side refrigeration circuit 20 supplies the brine. A configuration is adopted in which the brine is cooled by the evaporator 16 of the high temperature side refrigeration circuit 10 without cooling, but instead of such a configuration, even when the temperature of the brine is high, the high temperature side refrigeration circuit 10 (evaporation). A configuration in which the brine is cooled by both the cooler 16) and the low temperature side refrigeration circuit 20 (evaporator 24) can be employed.

  Further, although the refrigeration unit 2 having the high temperature side refrigeration circuit 10 including the evaporator 16 as the “third evaporator” has been described as an example, the electromagnetic valve 15a and the electronic expansion in the high temperature side refrigeration circuit 10 are described. A “refrigeration unit” (not shown) configured to cool the condenser 22 of the low temperature side refrigeration circuit 20 by the “first evaporator” of the “high temperature side refrigeration circuit” without the valve 15b and the evaporator 16 is provided. It can also be configured. When such a configuration is adopted, the pipe 5a in the hydrogen gas cooling device 1 may be directly connected to the pipe 5b.

  In addition, the configuration in which the temperature of the brine in the brine tank 4 is specified as an example in which the brine tank 4 is “predetermined position in the heat transfer medium circulation path” has been described, but “predetermined position” Is not limited to this example, and for example, the inside of the pipe 5a in the brine pipe 5 and the inside of the pipe 5e in the brine pipe 5 can be set as “predetermined positions”. Further, it is possible to adopt a configuration in which the temperature of the brine at the “predetermined position” is specified (calculated) based on the temperature of the brine at an arbitrary position in the brine pipe 5.

  Further, in place of the brine tank 4 in the hydrogen gas cooling device 1 described above, a brine tank (liquid storage tank) capable of storing brine that has passed through the evaporator 24 of each refrigeration unit 2 is provided, and hydrogen is supplied from the brine tank. It is also possible to adopt a configuration in which brine is supplied to the gas cooling heat exchanger 3 to cool the hydrogen gas. Specifically, as an example, among the components of the hydrogen gas cooling device 1 described above, the brine tank 4 is removed, the pipe 5e is directly connected to each pipe 5a, and the three-way valves Va, Vb and the pipe 5f are removed. The pipe 5c is directly connected to the pipe 5d, and as shown by a one-dot chain line in FIG. 1, the brine tank 8 (between the connection part of the pipe 5d with the pipe 5c and the part of the two-way valve Vc is provided An example of “second liquid storage tank” is provided.

  By adopting such a configuration, the brine cooled by each refrigeration unit 2 is stored in the brine tank 8 and then supplied from the brine tank 8 to the heat exchanger 3 for cooling the hydrogen gas, and the heat exchange for cooling the hydrogen gas. The brine recovered from the vessel 3 can be directly supplied to each refrigeration unit 2 and cooled, and then stored again in the brine tank 8. In the “hydrogen gas cooling device” configured to supply the brine from the brine tank 8 to the heat exchanger 3 for cooling the hydrogen gas, as an example, the control unit 7 has a “predetermined position in the heat transfer medium circulation path”. By performing either “Processing A” or “Processing B” according to the temperature of the heat transfer fluid in “As an example, in the brine tank 8”, the temperature is lowered as in the hydrogen gas cooling device 1 described above. Without causing a situation in which the refrigerant pressure in the side refrigeration circuit 20 becomes excessively high, the brine can be suitably cooled to a cryogenic temperature suitable for cooling hydrogen gas.

  Further, “when the first condition that the temperature difference between the inlet-side refrigerant temperature and the outlet-side refrigerant temperature in the second evaporator is equal to or lower than the first temperature defined in advance is substantially satisfied”. The state is not only the state when “the temperature difference between the inlet side refrigerant temperature and the outlet side refrigerant temperature in the second evaporator is equal to or lower than the first temperature defined in advance”, but also “the high temperature side refrigeration circuit” “Refrigerant temperature at a predetermined position in the low temperature side refrigeration circuit”, “refrigerant temperature at a predetermined position in the low temperature side refrigeration circuit”, “refrigerant pressure at a predetermined position in the high temperature side refrigeration circuit”, “low temperature side refrigeration” "Refrigerant pressure at a predetermined position in the circuit", "differential pressure of refrigerant pressure at two predetermined positions in the high temperature side refrigeration circuit", and "two predetermined positions in the low temperature side refrigeration circuit" `` Differential pressure of refrigerant pressure '' Is a value that satisfies the “first condition” that “the temperature difference between the inlet-side refrigerant temperature and the outlet-side refrigerant temperature in the second evaporator is equal to or lower than a first temperature that is defined in advance”. This state is included in this.

  Similarly, “when the second condition that the temperature difference between the inlet-side refrigerant temperature and the outlet-side refrigerant temperature in the second evaporator is equal to or higher than a predetermined second temperature is substantially satisfied”. Is not only the state when “the temperature difference between the inlet-side refrigerant temperature and the outlet-side refrigerant temperature in the second evaporator is equal to or higher than a predetermined second temperature”, but also “ “Refrigerant temperature at a predetermined position in the refrigeration circuit”, “refrigerant temperature at a predetermined position in the low temperature side refrigeration circuit”, “refrigerant pressure at a predetermined position in the high temperature side refrigeration circuit”, “low temperature” "Refrigerant pressure at a predetermined position in the side refrigeration circuit", "Differential pressure of refrigerant pressure at two predetermined positions in the high temperature side refrigeration circuit", and "Predetermined 2 in the low temperature side refrigeration circuit" `` Differential pressure of refrigerant pressure at two positions '' The “second condition” of “when the temperature difference between the inlet side refrigerant temperature and the outlet side refrigerant temperature in the second evaporator is equal to or higher than a predetermined second temperature” This includes a state that satisfies the value.

  In addition, the state that “condition A that the temperature of the heat transfer fluid at a predetermined position in the heat transfer fluid circulation path is equal to or higher than the predetermined temperature is substantially satisfied” A state in which “the temperature of the heat transfer liquid at a predetermined position is equal to or higher than a predetermined temperature” (for example, “the brine temperature in the brine tank 4 (predetermined position) is −33 ° C. (The temperature is “predetermined temperature) or higher”), as well as “the temperature of the heat transfer liquid at a position different from the predetermined position in the heat transfer medium circulation path”, “high temperature side freezing "Refrigerant temperature at a predetermined position in the circuit", "Refrigerant temperature at a predetermined position in the low temperature side refrigeration circuit", "Temperature difference between refrigerant temperatures at two predetermined positions in the high temperature side refrigeration circuit" "," Predefined in the low temperature side refrigeration circuit “Temperature difference between refrigerant temperatures at two positions”, “refrigerant pressure at a predetermined position in the high temperature side refrigeration circuit”, “refrigerant pressure at a predetermined position in the low temperature side refrigeration circuit”, “high temperature side refrigeration circuit” Various parameters such as “a differential pressure between refrigerant pressures at two predefined positions in the interior” and “a differential pressure between refrigerant pressures at two predefined positions within the low temperature side refrigeration circuit” This includes a state satisfying “Condition A” that the temperature of the heat transfer fluid at the position is equal to or higher than a predetermined temperature.

  Similarly, the state that “the condition B that the temperature of the heat transfer liquid at the predefined position is lower than the predefined temperature is substantially satisfied” is “the predefined position. State where the temperature of the heat transfer fluid is lower than a predetermined temperature (for example, “the temperature of the brine in the brine tank 4 (predetermined position) is −33 ° C. (predetermined temperature)) Not only in the state of “below”, but also “the temperature of the heat transfer fluid at a position different from the pre-defined position in the heat transfer fluid circulation circuit”, “the temperature in the high-temperature side refrigeration circuit in advance” “Refrigerant temperature at a prescribed position”, “refrigerant temperature at a prescribed position in the low temperature side refrigeration circuit”, “temperature difference between refrigerant temperatures at two prescribed positions in the high temperature side refrigeration circuit”, “low temperature” Predefined 2 in the side refrigeration circuit "Temperature difference in refrigerant temperature at the position of", "refrigerant pressure at a predetermined position in the high temperature side refrigeration circuit", "refrigerant pressure at a predetermined position in the low temperature side refrigeration circuit", "inside the high temperature side refrigeration circuit" Various parameters such as “the differential pressure of refrigerant pressure at two predetermined positions” and “the differential pressure of refrigerant pressure at two predetermined positions in the low temperature side refrigeration circuit” This includes a state that satisfies the value of “Condition B” that the temperature of the heat transfer fluid at the position is lower than a predetermined temperature.

  Further, it is possible to adopt a configuration in which brine is circulated between each refrigeration unit 2 and the heat exchanger 3 for cooling hydrogen gas without providing a “liquid storage tank” such as the brine tanks 4 and 8 (not shown). ) Further, an example of a configuration in which the hydrogen gas cooling process is started in conjunction with the output of the air supply start signal from the gas station side equipment X and the hydrogen gas cooling process is ended in conjunction with the output of the air supply end signal. As described above, instead of such a configuration, for example, the temperature of the brine flowing out from the hydrogen gas cooling heat exchanger 3 is monitored, and the hydrogen gas cooling heat exchanger is started along with the start of charging of the hydrogen gas. When the temperature of the brine flowing out from 3 becomes equal to or higher than the specified temperature, the cooling process of the hydrogen gas is started, and the temperature of the brine flowing out from the heat exchanger 3 for cooling the hydrogen gas as the filling of the hydrogen gas ends is the specified temperature. It is possible to adopt a configuration in which the cooling process of the hydrogen gas is terminated when the temperature is lower than.

DESCRIPTION OF SYMBOLS 1 Hydrogen gas cooling device 2a-2d Refrigeration unit 3 Heat exchanger for hydrogen gas cooling 3a, 4a, 24a, 24b Temperature sensor 4, 8 Brine tank 5 Brine piping 5a-5f Piping 6a, 6b Liquid feed pump 7 Control part 10 High temperature Side refrigeration circuit 11, 21 Compressor 12, 22 Condenser 13a, 15a Solenoid valve 13b, 15b, 23 Electronic expansion valve 14, 16, 24 Evaporator 20 Low temperature side refrigeration circuit 30 Cascade capacitor S3a, S4a, S24a, S24b Sensor signal Va, Vb Three-way valve Vc Two-way valve X Gas station side equipment

Claims (3)

A dual refrigeration circuit configured to cool the condenser of the low temperature side refrigeration circuit by the first evaporator in the high temperature side refrigeration circuit and to cool the heat transfer fluid by the second evaporator in the low temperature side refrigeration circuit; A plurality of refrigeration units;
A heat medium liquid pipe constituting a heat medium liquid circulation path for circulating the heat medium liquid between the refrigeration units and the heat exchanger for cooling hydrogen gas;
A plurality of the heat medium liquids connected to the heat medium liquid pipes and cooled by the respective refrigeration units are supplied to the hydrogen gas cooling heat exchanger and the heat medium liquids are recovered from the hydrogen gas cooling heat exchanger. Liquid feed pump,
A control unit for controlling the operation of each refrigeration unit and the liquid feed pump,
Each of the liquid feed pumps is connected to the plurality of different refrigeration units through the heat medium liquid pipe, and the heat medium liquid cooled by each of the refrigeration units is transferred to the hydrogen under the control of the control unit. Supply to heat exchanger for gas cooling,
The control unit adjusts the refrigeration capacity of each refrigeration unit so that the temperature of the heat transfer liquid at a predetermined position in the heat transfer liquid flow path is within a predetermined temperature range. While performing the capacity adjustment process, a temperature difference between the inlet side refrigerant temperature and the outlet side refrigerant temperature in the second evaporator of each refrigeration unit connected to any one of the liquid feed pumps is defined in advance. When the first condition that the temperature is equal to or lower than the first temperature is substantially satisfied in all of the refrigeration units, any one of the liquid feed pumps is operated, and hydrogen gas is cooled in the hydrogen gas cooling heat exchanger. In a state where at least one liquid feed pump is operated without cooling, and at least two liquid feed pumps are operated to cool the hydrogen gas in the hydrogen gas cooling heat exchanger. The temperature difference between the inlet-side refrigerant temperature and the outlet-side refrigerant temperature in the second evaporator of each refrigeration unit connected to one of the liquid feed pumps operating in any state is the first temperature. When the second condition that the temperature is equal to or higher than a predetermined second temperature higher than the temperature is substantially satisfied in any one of the refrigeration units, the second refrigeration unit is connected to the refrigeration unit. Only one liquid feeding pump is stopped, and only one liquid feeding pump is operated to cool the hydrogen gas in the hydrogen gas cooling heat exchanger. Hydrogen that maintains an operating state without stopping the liquid feed pump in operation when the second condition is substantially satisfied in any of the connected refrigeration units It is cooled equipment. The high temperature side refrigeration circuit includes a third evaporator capable of cooling the heat transfer fluid, a refrigerant supply amount adjusting valve for adjusting a supply amount of the refrigerant to the first evaporator and the third evaporator, With
The heating medium liquid pipe connects the evaporators for each refrigeration unit so that the heating medium liquid passes through the third evaporator and the second evaporator in this order,
The control unit substantially satisfies a condition A that the temperature of the heat transfer liquid at the predetermined position is equal to or higher than a predetermined temperature within the predetermined temperature range. Sometimes the processing A for cooling the heat transfer fluid by the third evaporator without cooling the heat transfer fluid by the second evaporator, and the temperature of the heat transfer fluid at the predetermined position When the condition B that the temperature is below the predetermined temperature is substantially satisfied, the refrigerant supply amount adjusting valve is controlled to control the supply amount of the refrigerant to the first evaporator. A process B for cooling the heat transfer fluid by the second evaporator while the condenser is cooled by the first evaporator is performed as the refrigeration capacity adjustment process. , In any of the refrigeration units When the process A is executed and the process B is executed in any one of the other refrigeration units connected to the liquid feed pump to which the refrigeration unit is connected, Any one of the refrigeration units and any other refrigeration unit are connected based on the temperature difference between the inlet side refrigerant temperature and the outlet side refrigerant temperature in the second evaporator of any one of the refrigeration units. The hydrogen gas cooling device according to claim 1, wherein it is determined whether to operate or stop the liquid feed pump. A first liquid storage tank configured to be able to store the heat medium liquid recovered from the hydrogen gas cooling heat exchanger and to be able to supply the stored heat medium liquid to the refrigeration units. And a second storage that is configured to store the heat medium liquid cooled by the refrigeration unit and that can store the stored heat medium liquid to the heat exchanger for cooling the hydrogen gas. At least one liquid storage tank and a liquid tank;
A temperature sensor disposed in the at least one liquid storage tank for detecting the temperature of the heat transfer fluid,
The hydrogen gas cooling according to claim 1 or 2, wherein the control unit specifies the temperature of the heat transfer fluid specified based on a sensor signal from the temperature sensor as the temperature of the heat transfer solution at the predetermined position. apparatus.

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