JP4711852B2 - Temperature adjusting device and refrigeration cycle - Google Patents

Description

  The present invention relates to temperature control of a fluid, and more particularly, to a temperature adjusting device that enables expansion of an operating range of the device and stable continuous operation, and a refrigeration cycle including the temperature adjusting device.

As a conventional technology, in order to cool the cold water that has returned to the refrigeration system by absorbing the heat load of the heating element, the inverter controls the operating frequency of the compressor of the refrigeration cycle and controls the capacity of the refrigeration capacity, so that it is always stable There is known a system for supplying cold water having a predetermined temperature. (See Patent Document 1)
Further, as a control method of the operating frequency, the deviation between the chilled water temperature and the chilled water set temperature is calculated for each sampling period, and the current deviation and the previous deviation are calculated using the proportional constant Kp and the integral constant Ki of the predetermined control constant. A method has been proposed in which the amount of change in frequency is calculated from the difference between the two, the amount of change in frequency is added to the previous frequency to determine the current operating frequency, and the temperature is output to an inverter. In the above method, a method of switching the proportional constant Kp and the integral constant Ki of the control constant according to the cold water temperature or the cold water set temperature has been proposed. (See Patent Document 2)

Japanese Patent Laid-Open No. 2-4165 JP-A-6-180152

In the refrigeration apparatus of Patent Document 1, the output frequency of the inverter is controlled based on the temperature of the chilled water returning from the load or the temperature of the chilled water supplied to the load, and the compressor is controlled by controlling the operating frequency of the compressor according to the value. This is a method that controls the functional force and cools the chilled water circulating between the load to the set temperature, but this method does not take into account the control constant that controls the output frequency of the inverter. When operating conditions such as the flow rate, the amount of retained water, and the cold water set temperature of cold water supplied to the load change, there is a problem that the cold water temperature cannot be kept constant and hunting may occur.
Further, in the refrigeration apparatus of Patent Document 2, it is necessary to determine in advance the control constant proportional constant Kp and integral constant Ki. Various methods such as "Ziegler-Nichols transient response method" have been proposed as a method for calculating the control constant, but either method is used to determine the control constant by measuring the transient response or using the calculated control constant. An actual machine test was necessary to confirm that there were no problems in all operating ranges.
And the subject that the man-hour of the real machine test performed for these control constant determination was large occurred.

  The first object of the present invention is to enable fluid temperature control over a wide range of operating conditions, and the second object is to immediately stabilize the fluid temperature even if the operating conditions change during operation. The third object of the control is to provide a temperature adjustment device that can reduce the number of man-hours for the actual machine test performed when determining the control constant.

The temperature adjusting device according to the present invention heat-exchanges in the heat exchanger with the refrigerant circulating in the refrigeration cycle in which the compression mechanism, the condenser, the expansion means for the cooler, and the cooler as the heat exchanger are sequentially connected in an annular shape. First temperature measuring means for measuring the fluid heat exchanger inlet side temperature, second temperature measuring means for measuring the fluid heat exchanger outlet side temperature, and fluid heat measured by the first temperature measuring means The difference between the temperature at the inlet side of the exchanger and the temperature at the outlet side of the target heat exchanger of the fluid (hereinafter referred to as the target temperature difference) is the heat of the fluid measured by the fluid heat exchanger inlet side temperature and the second temperature measuring means. The target compression function is obtained by multiplying the ratio (hereinafter referred to as the target capacity ratio) calculated by dividing the difference from the exchanger outlet temperature (hereinafter referred to as the current temperature difference) by the current compression function force. As a force, control that controls the capacity of the compressor based on this target compression function force It is those with a door.

The temperature adjusting device according to the present invention heat-exchanges in the heat exchanger with the refrigerant circulating in the refrigeration cycle in which the compression mechanism, the condenser, the expansion means for the cooler, and the cooler as the heat exchanger are sequentially connected in an annular shape. First temperature measuring means for measuring the fluid heat exchanger inlet side temperature, second temperature measuring means for measuring the fluid heat exchanger outlet side temperature, and fluid heat measured by the first temperature measuring means The difference between the temperature at the inlet side of the exchanger and the temperature at the outlet side of the target heat exchanger of the fluid is the difference between the temperature at the inlet side of the fluid heat exchanger and the temperature at the outlet side of the fluid heat exchanger measured by the second temperature measuring means. A value obtained by multiplying the ratio calculated by multiplying the current compression function force as a target compression function force, and a controller for controlling the compressor capacity based on this target compression function force .
Therefore, first, the capacity control is performed using the current temperature difference, so that the fluid temperature control is possible over a wide range of operating conditions. Second, since the capacity control is performed using the current temperature difference, the fluid temperature is controlled so as to immediately become stable even if the operating condition changes during operation. Third, since capacity control is performed using the current temperature difference, there is no need to determine the control constant in advance, and an actual machine test for determining the control constant is unnecessary.

Embodiment 1 FIG.
1 is a configuration diagram of a compressor-type refrigeration apparatus according to Embodiment 1 of the present invention.
In FIG. 1, a condenser 3 is connected to the refrigerant outlet side of the compressor 10 (the refrigerant flow circulates clockwise in the drawing). A condenser outlet 3 is connected to the refrigerant outlet side of the condenser 3. The cooler 5 is connected to the outlet side of the cooler expansion means 4, and the suction port of the compressor 10 is connected to the refrigerant outlet side of the cooler 5. The refrigeration cycle is configured by the above configuration.
Further, a temperature measuring means 400 for detecting the temperature of the cold water before heat exchange with the refrigerant is provided on the cooler cold water inlet side, and a temperature measuring means 401 for detecting the temperature of the cold water after heat exchange with the refrigerant is provided on the cooler cold water outlet side. The measured temperature is transmitted to the controller 200. The controller 200 adjusts the compression function of the compressor 10. The controller 200 can be realized by, for example, a microcomputer including a CPU and a non-volatile positive memory, and the CPU executes a compression function adjustment program installed in the non-volatile memory.
This is the same in all embodiments described later.

Next, the operation will be described.
Regarding the operation of the refrigeration cycle, the refrigerant discharged from the compressor 10 exchanges heat with cooling water, outside air, etc. in the condenser 3 to be condensed and liquefied to become high-pressure liquid refrigerant, and then the refrigerant expansion means 4 for the cooler. Thus, after the pressure is reduced to the suction pressure, it becomes a low-pressure two-phase refrigerant and flows into the cooler 5. The low-pressure two-phase refrigerant absorbs heat from the heat source in the cooler 5 and evaporates to reach the compressor 10.

Next, the temperature adjustment method of the present invention will be described.
From the cooler inlet side cold water temperature and the cooler outlet side cold water temperature measured by the temperature measuring means 400, 401, and the preset target cooler outlet side cold water temperature, the cooler inlet side cold water temperature and the cooler outlet side The difference between the chilled water temperature (hereinafter referred to as the current temperature difference) and the difference between the chiller inlet side chilled water temperature and the target chiller outlet side chilled water temperature (hereinafter referred to as the target temperature difference) are calculated. The ratio of the current temperature difference (hereinafter referred to as the target capacity ratio) is obtained. When the chilled water flow rate is constant, the value obtained by multiplying the obtained target capacity ratio by the current compression function force becomes the target compression function force, as shown in Expression 6 derived from Expressions 1 to 5. . Then, the compression function force control is performed so that the target compression function force obtained by the above procedure is obtained.

Current compression function force = (cooler inlet side cold water temperature-cooler outlet side cold water temperature)
X Cold water flow x Water specific heat (Formula 1)
Target compression function force = (cooler inlet side cold water temperature-target cooler outlet side cold water temperature)
X Cold water flow x Water specific heat (Formula 2)
Current temperature difference = Cooler inlet side cold water temperature-Cooler outlet side cold water temperature (Formula 3)
Target temperature difference = Cooler inlet side cold water temperature-Target cooler outlet side cold water temperature (Formula 4)
Target capacity ratio = target temperature difference / current temperature difference (Formula 5)
Target compression function force = Current compression function force x Target capacity ratio (Formula 6)

Here,-represents subtraction, x represents multiplication, and / represents division. These symbols are used in the same meaning in the following.
FIG. 2 shows a calculation example of the target compression function force. This calculation example will be described.
The current compression function is 100 kW. In addition, the current cooler inlet side cold water temperature is 12 ° C., and the current cooler outlet side cold water temperature is 7 ° C. The target cooler outlet side cold water temperature is set to 5 ° C. In this case, since the current temperature difference is the difference between the current cooler inlet side cold water temperature of 12 ° C. and the current cooler outlet side cold water temperature of 7 ° C., 12 ° C.−7 ° C. = 5 ° C. Moreover, since the target temperature difference is the difference between the current cooler inlet side cold water temperature of 12 ° C. and the target cooler outlet side cold water temperature of 5 ° C., 12 ° C.−5 ° C. = 7 ° C.
Therefore, the target capacity ratio is 7/5 because it is the target temperature difference / current temperature difference.
From the above, the target compression function force is the current compression function force x target capacity ratio.
100KW × 7/5 = 140KW

As a method of setting the compression function force as the target compression function force, there are a method of changing the number of rotations of the compressor, a method of adjusting by an unload mechanism for controlling the capacity of the compressor according to the load, and the like.
As a method of calculating the compression function force, a method of substituting the measured operation quantities such as the compressor discharge pressure and the compressor suction pressure into the capacity approximation formula calculated in advance may be used.

  According to the first embodiment, since the capacity control is performed using the current temperature difference, the fluid temperature can be controlled under a wide range of operating conditions. Further, since the capacity control is performed using the current temperature difference, it is possible to control the fluid temperature to be immediately stabilized even if the operating condition changes during operation. Furthermore, since the capacity control is performed using the current temperature difference, there is no need to determine the control constant in advance, and an actual machine test for determining the control constant becomes unnecessary.

In addition, although this Embodiment has shown the case where water is cooled, other fluids other than water, such as brine and air, may be sufficient as this fluid.
Although this embodiment shows the case where the fluid is cooled, the present invention can also be applied to the case where the fluid is heated.

Embodiment 2. FIG.
FIG. 3 is a configuration diagram of a compression refrigeration apparatus that performs rotation speed control by an inverter according to Embodiment 2 of the present invention.
FIG. 3 is obtained by adding an inverter 600 to FIG.
The controller 200 changes the frequency of the inverter 600, changes the rotation speed of the compressor, and adjusts the compression function force. Since the frequency control using the inverter 600 is more accurate than when the compressor unload mechanism is used, it is possible to adjust the fluid cooler outlet side temperature with higher accuracy.
The target compression function force calculation method of the present embodiment is the same as that of the first embodiment.

  According to the second embodiment, in addition to the effect of the first embodiment, there is an effect that the temperature of the fluid cooler outlet side can be adjusted with higher accuracy.

  In the second embodiment, the rotational speed is changed by the inverter. However, in the engine-driven compressed chilled water production apparatus, even if the rotational speed is changed by controlling the amount of fuel supplied to the engine. good.

Embodiment 3 FIG.
The screw compressor generally controls the compression function force by changing the slide valve position. However, when the method of the present invention is performed, the slide valve capacity% (here, the target compression function force) is obtained. ,% Needs to be calculated within the range of 0 to 100%, with 20% being fully closed and 100% being fully open. FIG. 4 shows an example of the relationship between the slide valve capacity% of the screw compressor and the cooling capacity.
As shown in FIG. 4, the slide valve capacity% and the cooling capacity are not directly proportional, and when the compressor inlet side evaporation temperature changes, the relationship between the slide valve capacity% and the cooling capacity also changes. For this reason, it is necessary to set an approximate expression of the relationship between the slide valve capacity% and the compression function force in advance. However, to create an approximate expression for the relationship between the slide valve capacity% and the compression function force, it is necessary to measure the capacity over the entire compressor operating range, but the capacity measurement requires a very large number of test steps. There was a problem.
FIG. 5 shows an example of the relationship between the compressor frequency of the screw compressor and the cooling capacity.
Since the screw compressor is a kind of positive displacement compressor, even if the compressor inlet side evaporation temperature changes as shown in FIG. 5, the compression function force is substantially proportional to the frequency. Therefore, when the frequency that will be the target compression function is the target frequency, Equation 9 is derived from Equations 7-8.

Current compression function force = K x current frequency (Equation 7)
Target compression function = K × target frequency (Formula 8)
Here, K is a proportionality constant.
Target frequency = current frequency x target capacity ratio (Equation 9)
Target capacity ratio = target compression capacity / current compression capacity (Formula 10)

As shown in Equation 9, the target frequency can be derived from the current frequency and the target capability ratio. Therefore, the controller 200 performs compressor frequency control so that the target frequency obtained in the above procedure is obtained.

  In the temperature adjustment method according to the third embodiment, in addition to the effects of the first embodiment, it is not necessary to calculate the current compression function force and the target compression function force. There is an effect that it is not necessary to measure the capability over the entire operating range.

Embodiment 4 FIG.
The configuration diagram of FIG. 1 or 3 is also used in the fourth embodiment.
Instantaneous change from the current compression function force to the calculated target compression function force causes fluid freezing in the heat exchanger due to a sudden drop in compressor suction evaporation temperature, and compressor damage due to a sudden rise in compressor discharge condensation temperature. May occur.
In order to prevent these problems, the target compression function force is calculated at regular intervals (hereinafter referred to as a compression function force determination cycle), and after the target compression function force is calculated, the target compression function force is gradually changed. .
Since the compression function force is not changed abruptly, the above-mentioned problem can be prevented by protection control or the like before it occurs.
FIG. 6 is a conceptual diagram of a compression function force changing method according to Embodiment 4 of the present invention.
In the example of FIG. 6, the compression function force is changed so that the compression function force becomes the target compression function force at the moment when the next compression function force determination cycle arrives. The compression function force change may be terminated before the function force determination. In this case, since the compression function force is determined when the compression function force is stable after the compression function force is changed, the occurrence of hunting is generated as compared with the case of FIG. 6 in which the compression function force determination is performed when the compression function force is not stable. Can be reduced.

According to the fourth embodiment, the target compression function force is calculated in the compression function force determination cycle, and after the target compression function force is calculated, the target compression function force is gradually changed. In addition to the effect, there is an effect that the compression function force can be changed to the target value without the problem of fluid freezing in the heat exchanger and the problem of occurrence of damage to the compressor.
Furthermore, since the compression function force change is completed before the next compression function force determination, in addition to the above effects, there is an effect that the occurrence of hunting can be reduced.

Embodiment 5. FIG.
When the target compression function force calculated in the compression function force judgment cycle is significantly different from the current compression function force, such as when the compressor starts up or when the thermal load fluctuates rapidly, the capacity change rate of the compressor is faster. As a result, the fluid may freeze in the heat exchanger due to a sudden drop in the compressor suction evaporation temperature, or the compressor may be damaged due to a sudden rise in the compressor discharge condensation temperature.
In order to prevent these problems, a certain limit may be provided in calculating the target compression function force.
As a method of limiting the target compression function force, a method of setting a limit based on the current compression function force as in Expressions 11 and 12, or a limit on the frequency change rate per unit time as in Expressions 13 and 14 A method of providing it is conceivable.

Target compression function force upper limit = current compression function force x upper limit constant (Formula 11)
Target compression function force lower limit = current compression function force x lower limit constant (Equation 12)
Here, the upper limit constant and the lower limit constant are set in advance.

Target compression function force upper limit = compression function force change time × maximum increase rate of change (Formula 13)
Target compression function force lower limit = compression function force change time x maximum descent change rate (Formula 14)
Here, the maximum rise change rate and the maximum fall change rate (Hz / S) are set in advance.

In any method, when the target compression function force calculated in the compression function force determination cycle is equal to or higher than the target compression function force upper limit value, the target compression function force is set as the target compression function force upper limit value, and the target compression function force is set as the target compression function force. When the force is lower than the lower limit value, the target compression function force is set as the target compression function force lower limit value.
FIG. 8 is a conceptual diagram of a compression function force changing method according to Embodiment 5 of the present invention.

According to the fifth embodiment, the target compression function force is limited based on the current compression function force. In addition to the effects of the first embodiment, the fluid freezing in the heat exchanger There is no problem, and there is an effect that the compression function force can be changed to the target value without a problem of occurrence of damage to the compressor.
Further, since the restriction on the target compression function force is provided based on the frequency change rate per unit time, in addition to the effect of the first embodiment, there is no problem of fluid freezing in the heat exchanger, and compression is performed. There is an effect that the compression function force can be changed to the target value without any problem of machine damage.

Embodiment 6 FIG.
When there is a measurement error in the water temperature sensor, the fluid heat exchanger outlet side temperature may reach the target temperature before the compression function force reaches the calculated target compression function force. In such a case, when the compression function force reaches the calculated target compression function force, a phenomenon occurs in which the fluid heat exchanger outlet side temperature deviates from the target temperature. FIG. 9 is an image diagram of this phenomenon.
In such a case, when it is detected that the temperature of the fluid heat exchanger outlet side has reached the target temperature, the compression function force change is stopped and the compression function force is reached until the target temperature is reached until the next compression function force determination cycle. Fix to the compression function force of.
FIG. 10 shows a conceptual diagram of changing the compression function force in the present embodiment.
According to the sixth embodiment, by performing the above control, an overshoot of the compression function force can be prevented, so that an effect that the temperature control is stabilized is achieved.

Embodiment 7 FIG.
In the control of the seventh embodiment, the compression function force is changed until the fluid heat exchanger outlet temperature matches the target temperature. For this reason, even if the fluid heat exchanger outlet side temperature is close to the target temperature to the extent that there is no practical problem, the compression function force is changed, so that the fluid heat exchanger outlet temperature causes hunting. Sometimes.
In order to prevent such a problem, in the seventh embodiment, an area called a dead zone is set in a range where there is no practical problem in the vicinity of the target temperature. In this case, the dead zone region can be arbitrarily set by the user from the outside, and the set value is determined according to the environmental conditions. When the fluid heat exchanger outlet side temperature enters from the outside of the dead zone to the inside of the dead zone during the compression function force change, the change in the compressor capacity is terminated. If the fluid heat exchanger outlet side temperature is within the dead zone during the compression function force determination cycle, the compression function force is not changed. As a result, unnecessary compression function force change is not performed, hunting of the fluid heat exchanger outlet side temperature can be prevented, and temperature control is stabilized.
FIG. 11 is an image of a control area according to the seventh embodiment.
FIG. 12 is a control flow diagram of the controller 200 in the seventh embodiment.
Next, the operation of the controller 200 in the seventh embodiment will be described with reference to the flowchart of FIG.
The operation flow of FIG. 12 is performed by the controller 200 regularly or irregularly.
In this operation flow, the controller 200 first checks whether or not the heat exchanger outlet side temperature is within the dead zone (step S121). If the temperature on the outlet side of the heat exchanger is within the dead zone, the compressor capacity is not changed (step S122), and the process ends. If the temperature at the outlet side of the heat exchanger is not the dead zone, the controller 200 calculates the target compression function force (step S123), and then starts changing the compression function force toward the target compression function force (step S124). . Next, the controller 200 checks whether or not the heat exchanger outlet side temperature is within the dead zone (step S125). If the temperature on the outlet side of the heat exchanger is within the dead zone, the process jumps to step S128. If the heat exchanger outlet side temperature is not the dead zone, the controller 200 checks whether the compression function force has reached the target compression function force (step S126). When the compression function force reaches the target compression function force, the process jumps to step S128. In step S128, the controller 200 ends the compressor capacity change. If the compression function force does not reach the target compression function force, the process returns to step S125.

  According to the seventh embodiment, when the fluid heat exchanger outlet side temperature enters the dead zone from outside the dead zone during the compression function change, the unnecessary compressor capacity change is terminated, and the compression function When the fluid heat exchanger outlet side temperature is within the dead zone during the force judgment cycle, unnecessary compression function force change is not performed, so hunting of the fluid heat exchanger outlet temperature can be prevented. The temperature control is stable.

Embodiment 8 FIG.
Even after completion of the compression function force change, the fluid heat exchanger outlet side temperature may change until the operation state of the refrigerator is stabilized or due to a delay in response of the temperature sensor. In particular, when the compression function force is greatly changed, the change in the heat exchanger outlet temperature of the fluid generated after the change of the compression function force is apt to be large.
If the dead zone is narrow, even if the compression function force change ends when the fluid heat exchanger outlet side temperature enters the dead zone, the fluid heat exchanger outlet temperature change after the compression function force change ends. The temperature at the outlet side of the heat exchanger of the fluid may deviate from the dead zone. When such a phenomenon occurs, the fluid heat exchanger outlet side temperature may cause hunting around the target temperature.
FIG. 13 shows an image diagram of this phenomenon.

In order to prevent such a problem, in the eighth embodiment, an area called a differential area including a dead zone is set near the target temperature. In this case, the differential area can be arbitrarily set from the outside by the user, and the set value is determined according to the environmental conditions. If the fluid heat exchanger outlet side temperature enters the differential area from outside the differential area during the compression function force change, the capacity change of the compressor is stopped.
FIG. 14 is a diagram illustrating the relationship between the heat exchanger outlet side temperature and the control region according to the eighth embodiment.
In the control of the eighth embodiment, the compression function force is temporarily fixed before the fluid heat exchanger outlet side temperature enters the dead zone, and the target compression function force is restored again in the vicinity of the dead zone and in a state where the operation of the refrigerator is stable. Therefore, the difference between the current compression function force and the target compression function force is reduced, the amount of temperature change after the change of the compression function force is reduced, and the temperature at the outlet side of the fluid is insensitive after the change of the compression function force is finished. No hunting out of band.
As a result, the temperature control is stabilized.
FIG. 15 is an image diagram of the heat exchanger outlet side temperature of the fluid after application of control in the eighth embodiment.
FIG. 16 is a control flowchart of the eighth embodiment.
Next, the operation of the controller 200 in the eighth embodiment will be described with reference to the flowchart of FIG.
The operation flow of FIG. 16 is performed by the controller 200 regularly or irregularly.
First, in this operation flow, the controller 200 checks whether or not the heat exchanger outlet side temperature is within the dead zone (step S160). If the temperature on the outlet side of the heat exchanger is within the dead zone, the compressor capacity is not changed (step S161), and the process ends. If the temperature on the outlet side of the heat exchanger is not the dead zone, the controller 200 calculates the target compression function force (step S162) and then starts changing the compression function force toward the target compression function force (step S163). . Next, the controller 200 checks whether or not the heat exchanger outlet side temperature is within the differential region (step S164). If the temperature on the outlet side of the heat exchanger is within the differential region, the process proceeds to step S168, and if not within the differential region, the process proceeds to step S165.
In step S165, the controller 200 checks whether or not the heat exchanger outlet side temperature is within the differential region. If the heat exchanger outlet side temperature is within the differential region, the process proceeds to step S167, and if not within the differential region, the process proceeds to step S166. In step S166, the controller 200 checks whether the compression function force has reached the target compression function force. If the compression function force reaches the target compression function force, the process proceeds to step S167, and if the compression function force does not reach the target compression function force, the process returns to step S168. In step S167, the controller 200 ends the compressor capacity change.
In step S168, the controller 200 checks whether or not the heat exchanger outlet side temperature is within the dead zone. If the temperature on the outlet side of the heat exchanger is within the dead zone, the process proceeds to step S167, and if not, the process proceeds to step S169. In step S169, the controller 200 checks whether the compression function force has reached the target compression function force. If the compression function force reaches the target compression function force, the process proceeds to step S167, and if the compression function force does not reach the target compression function force, the process returns to step S168. In step S167, the controller 200 ends the compressor capacity change.

  According to the eighth embodiment, the compression function force is temporarily fixed before the fluid heat exchanger outlet side temperature enters the dead zone, and the target compression function force is set again in the vicinity of the dead zone and in a state where the operation of the refrigerator is stable. Since the determination is made, there is an effect that the temperature at the outlet side of the fluid does not deviate from the dead zone and the hunting is not performed after the compression function force is changed.

It is a block diagram of the compressor type refrigeration apparatus in Embodiment 1 of this invention. It is a conceptual diagram of the target ability calculation method in Embodiment 1 of this invention. It is a block diagram of the compression-type refrigeration apparatus which performs rotation speed control by the inverter in Embodiment 2 of this invention. It is the figure which showed the relationship between the frequency and cooling capacity in an electric motor drive positive displacement compressor. It is the figure which showed the relationship between the slide valve capacity | capacitance and cooling capacity in the positive displacement compressor of an electric motor drive. It is a conceptual diagram of the compression function force change method in Embodiment 4 of this invention (the 1). It is a conceptual diagram of the compression function force change method in Embodiment 4 of this invention (the 2). It is a conceptual diagram of the compression function force change method in Embodiment 5 of this invention. It is an image figure which shows the phenomenon which generate | occur | produces in the heat exchanger exit side temperature when there exists a measurement error in the sensor in Embodiment 6 of this invention and the target temperature is reached. It is a conceptual diagram of the compression function force change method at the time of reaching target temperature in Embodiment 6 of this invention. It is a figure which shows the relationship between the heat exchanger exit side temperature and control area in Embodiment 7 of this invention. It is a control flow figure in Embodiment 7 of this invention. It is an image figure which shows the phenomenon which generate | occur | produces in the heat exchanger exit side temperature after the compression function force change before control application in Embodiment 8 of this invention. It is a figure which shows the relationship between the heat exchanger exit side temperature and control area in Embodiment 8 of this invention. It is an image figure of the heat exchanger exit side temperature of the fluid after control application in Embodiment 8 of this invention. It is a control flow figure in Embodiment 8 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 condenser, 4 expansion means for coolers, 5 coolers, 10 compressors, 200 controllers, 400 cooler inlet side cold water temperature detection means, 401 cooler outlet side cold water temperature detection means, 600 inverter

Claims (11)

The heat exchanger inlet side of the refrigerant that circulates in the refrigeration cycle in which the compression mechanism, the condenser, the expansion means for the cooler, and the cooler that is the heat exchanger are sequentially connected in an annular manner and the fluid that is heat-exchanged in the heat exchanger First temperature measuring means for measuring temperature;
Second temperature measuring means for measuring the temperature of the fluid on the outlet side of the heat exchanger;
The first difference of temperature measuring means and the heat exchanger inlet side temperature and the fluid of the target heat exchanger outlet temperature of the fluid measured, the said heat exchanger inlet side temperature of the fluid second temperature The value obtained by multiplying the ratio calculated by dividing the difference between the fluid measured by the measuring means and the temperature at the outlet side of the heat exchanger by the current compression function force is used as the target compression function force. And a controller for controlling the capacity of the compressor based on the temperature control device.   The temperature controller according to claim 1, wherein the controller controls the compression function force by changing a rotation speed of the compressor. Equipped with an unload mechanism that controls the capacity of the compressor according to the load,
The temperature controller according to claim 1, wherein the controller controls the capacity of the compressor using the unload mechanism. It has a frequency converter that changes the rotation speed of the compressor,
The temperature controller according to claim 2, wherein the controller controls the capacity of the compressor using the frequency converter. The heat exchanger inlet side of the refrigerant that circulates in the refrigeration cycle in which the compression mechanism, the condenser, the expansion means for the cooler, and the cooler that is the heat exchanger are sequentially connected in an annular manner and the fluid that is heat-exchanged in the heat exchanger First temperature measuring means for measuring temperature;
Second temperature measuring means for measuring the temperature of the fluid on the outlet side of the heat exchanger;
The first difference of temperature measuring means and the heat exchanger inlet side temperature and the fluid of the target heat exchanger outlet temperature of the fluid measured, the said heat exchanger inlet side temperature of the fluid second temperature A value obtained by multiplying the ratio calculated by dividing the difference between the fluid measured by the measuring means and the temperature at the outlet side of the heat exchanger by the current frequency is set as a target frequency, and the compressor is based on the target frequency. And a controller for controlling the performance.   The temperature controller according to claim 1, wherein the controller gradually controls the compression function force toward the calculated target compression function force when controlling the compression function force.   The controller, when controlling the compression function force, if the difference between the calculated target compression function force and the current compression function force is greater than a preset upper limit target compression function force variation range, the target compression function force Is the upper limit target compression function force change width, or if it is smaller than the preset lower limit target compression function force change width, the target compression function force change width is set as the lower limit target compression function force change width. The temperature adjusting device according to claim 6, wherein   When the temperature of the fluid heat exchanger outlet side reaches the target temperature, the controller temporarily fixes the compression function force. When the target compression function force is calculated in the next compression function force determination cycle, the controller compresses the compression function force. The temperature control apparatus according to claim 6 or 7, wherein the control of the functional force is resumed.   The controller presets a predetermined temperature range near the target temperature and including the target temperature as a dead zone region, and when the temperature of the fluid heat exchanger outlet side reaches the dead zone region from outside the dead zone region, the compression function force is increased. Control is complete | finished, The temperature control apparatus of any one of Claims 6-8 characterized by the above-mentioned.   The controller presets a differential region within a predetermined temperature range near the target temperature and including the dead zone region, and when the fluid heat exchanger outlet temperature reaches the differential region from outside the differential region, the compression function force is temporarily increased. The temperature adjusting device according to claim 9, wherein the control of the compression function force is resumed when the target compression function force is calculated in the next compression function force determination cycle.   A refrigeration cycle comprising the temperature adjusting device according to any one of claims 1 to 10.

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