JP2015117899A - Heat pump device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat pump device capable of performing an efficient load operation such as a heating operation and the like even when a load is small.SOLUTION: A heat pump device 100 includes control means 22 which detects information showing frequency of occurrence of at least one of activation and stop of a compressor 2, and when it is determined that the frequency has reached a predetermined high frequency region (Step S5: Yes), it controls a target rotation speed at rise time of a geothermal heat circulation pump 13 to be lower than a maximum rotation speed, which is a predetermined set value (Step S6).

Description

  The present invention relates to a heat pump device, and more particularly to a geothermal heat pump device that uses geothermal heat.

2. Description of the Related Art Conventionally, as an example of a heat pump apparatus, a hot water circulation type underground heat pump apparatus that uses underground heat is known.
As shown in FIG. 9, this type of geothermal heat pump apparatus includes a heat pump circuit 107 in which a compressor 102, a load side heat exchanger 103, a decompression unit 104, and a heat source side heat exchanger 105 are connected in a ring shape with refrigerant piping. A heat source side circulation circuit 112 in which a heat source side heat exchanger 105 and a ground heat exchanger 110 as a heat source installed in the ground are connected in a ring shape with a heat medium pipe, and a heat medium to the heat source side circulation circuit 112 A heat source side circulation pump 113 to be circulated, a load terminal 115 such as a floor heating panel, and a load side circulation circuit 118 in which the load side heat exchanger 103 is annularly connected by a heat medium pipe, and a heat medium to the load side circulation circuit 118 And a load-side circulation pump 116 for circulation.

  In this underground heat pump device, the heat source side heat exchanger 105 functions as an evaporator and the load side heat exchanger 103 functions as a condenser, and a load operation such as a heating operation in which the air-conditioned space is heated by the load terminal 115 is performed. . Then, during the load operation, the geothermal heat pump device, for example, the rotation speed (the number of rotations per unit time) of the heat source side circulation pump 113 so that the temperature of the refrigerant on the heat source side heat exchanger 105 side becomes a predetermined target temperature. ) Is controlled (see Patent Document 1). According to this, optimum heat collection can be performed by quickly grasping the load output variation due to the refrigerant temperature variation and adjusting the flow rate of the heat medium circulating in the heat source side circulation circuit 112.

JP 2011-94840 A

  By the way, for example, a load such as a heating load in a house may be large or small and is not always constant. When the load is small, the set target temperature is quickly reached when the load operation is executed, so even if the compressor or heat source side circulation pump is activated (driven), it stops in a short time, and the compressor or heat source side There is a possibility that the circulation pump repeatedly repeats from the stopped state to the driven state. In this case, in accordance with the control at the time of rising of the heat pump device, the heat source side circulation pump is always set to the maximum rotation speed that is a preset value determined as the target rotation speed at the time of rising, even though the load is small. When it starts up, power consumption becomes large and SCOP (system performance coefficient) deteriorates.

  This invention is made | formed in view of an above described situation, and makes it a subject to provide the heat pump apparatus which can perform load operation, such as efficient heating operation, even when load is small.

  In order to solve the above-mentioned problem, the invention according to claim 1 includes a heat pump circuit in which a compressor, a load-side heat exchanger, a decompression unit, and a heat-source-side heat exchanger are connected in a ring shape with a refrigerant pipe, and the heat-source-side heat. At least one of an exchanger, a heat source side circulation circuit in which the heat source is connected in a ring shape with a heat medium pipe, a heat source side circulation pump that circulates the heat medium in the heat source side circulation circuit, the compressor, and the heat source side circulation pump When information indicating the frequency of occurrence of at least one of activation and stop is detected and it is determined that the frequency has reached a predetermined high-frequency region, a target rotational speed at the time of rising of the heat source side circulation pump is determined in advance. And a control means for performing control for lowering the set value than the set value.

According to such a configuration, when the load such as the heating load is small, the compressor of the heat pump device and the heat source side circulation pump may repeat the activation, but when the frequency of such activation is high, The target rotational speed at the time of rising of the heat source side circulation pump is lowered from a predetermined set value. In this case, since the heat source side circulation pump does not reach the maximum rotational speed that is a predetermined set value at the time of startup, the overall efficiency of the heat pump device is improved.
That is, it is possible to provide a heat pump device that can perform load operation such as efficient heating operation even when the load is small.

  The invention according to claim 2 is the heat pump device according to claim 1, wherein the information includes at least activation and stop of at least one of the compressor and the heat source side circulation pump within a predetermined set time. The number of occurrences is one, and the high-frequency area is an area in which the number of times is equal to or more than a predetermined number of times.

  According to such a configuration, it is reliably executed by simple processing whether or not the frequency of occurrence and / or stop of at least one of the compressor and the heat source side circulation pump has reached the high frequency region. can do.

  The invention according to claim 3 is the heat pump device according to claim 1, wherein the information is a generation cycle of activation or stop of at least one of the compressor and the heat source side circulation pump, and the high-frequency region. Is a region where the generation period is equal to or less than a predetermined set period.

  According to such a configuration, the frequency at which at least one of starting and stopping of at least one of the compressor and the heat source side circulation pump occurs without requiring waiting for the elapse of a preset time as a check period. It can be determined whether or not the high frequency area has been reached. Therefore, for example, as soon as the period between the previous activation and the current activation (occurrence period of the activation) becomes equal to or less than the set period, the target rotational speed at the rise of the heat source side circulation pump is made higher than the maximum rotational speed. Since it can be lowered, it is possible to respond more quickly and to perform more efficient load operation.

  The invention according to claim 4 is the heat pump apparatus according to any one of claims 1 to 3, wherein the control means determines that the frequency has shifted from the inside of the high-frequency region to the outside. In this case, control is performed to return the target rotational speed at the time of rising of the heat source side circulation pump to the set value.

  According to such a configuration, necessary heat collection from the ground or necessary heat radiation to the ground can be performed more appropriately.

  According to the present invention, it is possible to provide a heat pump device capable of performing a load operation such as an efficient heating operation even when the load is small.

It is a schematic block diagram of the heat pump apparatus which concerns on one Embodiment of this invention. It is a flowchart which shows the content of the process which sets the target rotational speed at the time of a rise of a geothermal circulation pump at the time of heating operation. It is a time chart showing a motion of each parameter of a heat pump device at the time of heating operation. It is a schematic block diagram of the heat pump apparatus which concerns on other embodiment of this invention. It is a schematic block diagram which shows the state at the time of the heating operation of a heat pump apparatus. It is a schematic block diagram which shows the state at the time of the cooling operation of a heat pump apparatus. It is a flowchart which shows the content of the process which sets the target rotational speed at the time of start-up of a geothermal circulation pump at the time of air_conditionaing | cooling operation. It is a time chart showing a motion of each parameter of a heat pump device at the time of air conditioning operation. It is a schematic block diagram of the conventional heat pump apparatus.

Embodiments of the present invention will be described in detail with reference to the drawings as appropriate.
Note that, in the drawings shown below, the same members or corresponding members are denoted by the same reference numerals, and redundant description is omitted as appropriate.

  FIG. 1 is a schematic configuration diagram of a heat pump apparatus 100 according to an embodiment of the present invention. The heat pump device 100 according to the present embodiment is a hot water circulation type geothermal heat pump device that uses geothermal heat.

  As shown in FIG. 1, the heat pump device 100 according to this embodiment includes a heat pump circuit 7 built in the heat pump unit 1, a ground heat circulation circuit 12 as a heat source side circulation circuit, and heating as a load side circulation circuit. And a circulation circuit 18.

  The heat pump circuit 7 circulates the variable capacity compressor 2 that compresses the refrigerant and the high-temperature refrigerant discharged from the compressor 2, and performs heat exchange between the high-temperature refrigerant and the heat medium that flows through the heating circulation circuit 18. As the load side heat exchanger 3, the expansion valve 4 as pressure reducing means for depressurizing the refrigerant flowing out from the load side heat exchanger 3, and the low temperature refrigerant depressurized from the expansion valve 4 is circulated and this low temperature refrigerant and the underground The heat source side heat exchanger 5 as an evaporator that performs heat exchange with the heat medium flowing through the heat circulation circuit 12 and a refrigerant pipe 6 that connects these in an annular shape are configured.

  In addition, as a refrigerant | coolant of the heat pump circuit 7, arbitrary refrigerant | coolants, such as a carbon dioxide refrigerant | coolant and a HFC refrigerant | coolant, can be used. In FIG. 1, reference numeral 8 is a refrigerant discharge temperature sensor that detects the temperature of the refrigerant discharged from the compressor 2, and reference numeral 9 is a heat source side heat exchanger from the expansion valve 4 to the compressor 2. This is a refrigerant temperature sensor that is provided in the refrigerant pipe 6 on the fifth side, that is, the refrigerant pipe 6 on the low pressure side, and detects the temperature of the refrigerant on the low pressure side.

  The load side heat exchanger 3 and the heat source side heat exchanger 5 are configured by, for example, a plate heat exchanger, and the plate heat exchanger has a refrigerant flow path in which a plurality of heat transfer plates are stacked and the refrigerant flows. And a fluid flow path for circulating a fluid as a heat medium are alternately formed with each heat transfer plate as a boundary.

  The underground heat circulation circuit 12 connects the heat source side heat exchanger 5, the underground heat exchanger 10 installed in the ground as a heat source for heating the refrigerant flowing through the heat source side heat exchanger 5, and these in a ring shape And a underground heat pipe 11 as a heat medium pipe to be configured. In addition, the underground heat pipe 11 is a heat source side circulation pump having a variable rotation speed (the number of rotations per unit time) for circulating an antifreeze liquid added with ethylene glycol, propylene glycol or the like as a heat medium in the underground heat circulation circuit 12. The underground heat circulation pump 13 is provided. In addition, the code | symbol 14 in FIG. 1 is an underground systern which stores an antifreeze and adjusts the pressure of the underground heat circulation circuit 12.

  Here, in the geothermal circulation circuit 12, when performing the load operation described later, the geothermal heat exchanger 10 collects the geothermal heat from the ground, and the antifreeze liquid with the heat is collected in the geothermal circulation pump 13. Is supplied to the heat source side heat exchanger 5. Then, in the heat source side heat exchanger 5, the refrigerant flowing through the refrigerant flow path of the heat source side heat exchanger 5 and the antifreeze liquid flowing through the fluid flow path of the heat source side heat exchanger 5 flow oppositely to exchange heat. The underground heat collected by the underground heat exchanger 10 is pumped to the refrigerant side of the heat pump unit 1 to heat the refrigerant, and the heat source side heat exchanger 5 functions as an evaporator.

  The heating circulation circuit 18 includes a load-side heat exchanger 3, a heat radiating terminal 15 as a load terminal such as a floor heating panel or a panel convector that heats the air-conditioned space, and heating as a heat medium pipe that connects them in a ring shape. A pipe 17 is provided. The heating pipe 17 is provided with a heating circulation pump 16 as a load-side circulation pump that circulates a circulating fluid such as warm water as a heating medium in the heating circulation circuit 18. Each of these is provided with a thermal valve 19 for controlling the supply of the circulating fluid to the heat radiating terminal 15 by opening and closing.

In FIG. 1, reference numeral 21 denotes a return hot water temperature sensor that is provided in the heating pipe 17 and detects the temperature of the circulating fluid flowing into the load side heat exchanger 3 from the heat radiating terminal 15, and reference numeral 20 denotes the circulating fluid. This is a heating systern that stores and adjusts the pressure of the heating circulation circuit 18.

  A remote controller 23 is installed in each air-conditioned space heated by the heat radiating terminal 15. When the remote controller 23 gives an instruction to heat the air-conditioned space, the compressor 2, the underground heat circulation pump 13, and The heating circulation pump 16 starts to be driven, and the heat source side heat exchanger 5 functions as an evaporator, and the load side heat exchanger 3 functions as a condenser to perform a heating operation as a load operation for heating the load side. Is called. During the heating operation, in the load-side heat exchanger 3, the refrigerant flowing through the refrigerant flow path of the load-side heat exchanger 3 and the circulating fluid flowing through the fluid flow path of the load-side heat exchanger 3 flow in opposition. The heat exchange is performed to heat the circulating fluid, and the heated circulating fluid is sent to the heat radiating terminal 15 through the thermal valve 19 to heat the air-conditioned space designated by the remote controller 23.

  The heat pump unit 1 is provided with a control means 22, which receives detection signals from the refrigerant discharge temperature sensor 8, the refrigerant temperature sensor 9, the return hot water temperature sensor 21, and an operation signal from the remote controller 23. The microcomputer 2 controls the drive of each actuator of the compressor 2, the expansion valve 4, the underground heat circulation pump 13, and the heating circulation pump 16.

  The control means 22 controls the rotational speed of the compressor 2 so that the temperature of the circulating fluid detected by the return hot water temperature sensor 21 becomes the set target heating temperature during the heating operation. When the temperature of the circulating fluid to be detected falls below the set target heating temperature, the rotation speed of the compressor 2 is controlled to increase.

  Moreover, the control means 22 sets the target discharge temperature of the refrigerant | coolant discharged from the compressor 2 based on the setting temperature set with the remote control 23 at the time of heating operation, and the compression which the refrigerant | coolant discharge temperature sensor 8 detects during heating operation. The opening degree of the expansion valve 4 is controlled so that the temperature of the refrigerant discharged from the machine 2 becomes the set target discharge temperature. For example, the refrigerant discharge temperature detected by the refrigerant discharge temperature sensor 8 is set. When the temperature drops below the target discharge temperature, the opening degree is controlled to close.

  Moreover, the control means 22 controls to raise the rotation speed of the geothermal circulation pump 13 to the target rotation speed when the underground heat circulation pump 13 rises. Furthermore, the control means 22 sets the low-pressure-side refrigerant temperature detected by the refrigerant temperature sensor 9 after a specified time (for example, 2 minutes) has elapsed since the completion of the rise of the underground heat circulation pump 13 to the target rotational speed. When the rotational speed of the underground heat circulation pump 13 is controlled to reach the target temperature, for example, when the refrigerant temperature on the low-pressure side detected by the refrigerant temperature sensor 9 falls below the set target temperature, the underground heat circulation pump 13 Is controlled so as to increase the rotation speed.

  In addition, when the control means 22 detects information indicating the frequency at which at least one of activation and stop of the compressor 2 occurs and determines that the frequency has reached a predetermined high frequency area, The target rotational speed at the time of starting up the pump 13 is set lower than the maximum rotational speed (for example, 4000 rpm) which is a predetermined setting value, specifically, an upper limit rotational speed (for example, 2000 rpm) lower than the maximum rotational speed. It controls to do. In the present embodiment, the information is the number of times that the compressor 2 is activated within a predetermined setting time (for example, 30 minutes), and the high-frequency area has a predetermined number of times (the number of times the predetermined number is determined in advance). For example, it is an area that becomes at least twice. This makes it possible to reliably determine whether or not the frequency of occurrence of at least one of starting and stopping of the compressor 2 has reached the high-frequency area with a simple process. Note that the values of the upper limit rotation speed, the set time, and the set number of times can be changed as appropriate.

Next, with reference to the flowchart of FIG. 2, operation | movement of the geothermal circulation pump 13 mainly at the time of the heating operation of the heat pump apparatus 100 shown in FIG. 1 is demonstrated.
FIG. 2 is a flowchart showing the contents of processing for setting the target rotational speed when the underground heat circulation pump 13 rises during heating operation.

  When an instruction for heating (heating) of the air-conditioned space is given from the remote control 23 by the heat radiating terminal 15, the control means 22 starts driving the compressor 2, the underground heat circulation pump 13, and the heating circulation pump 16, and the load Heating operation as operation is started. When the heating operation is started, the load-side heat exchanger 3 exchanges heat between the circulating fluid circulated by the heating circulation pump 16 and the high-temperature and high-pressure refrigerant discharged from the compressor 2, and the heated circulating fluid radiates heat. While supplying the terminal 15 to heat the air-conditioned space, the heat source side heat exchanger 5 is circulated by the ground heat circulation pump 13, and the antifreeze liquid and the expansion valve that have collected the ground heat through the ground heat exchanger 10. Heat exchange with the low-temperature and low-pressure refrigerant discharged from 4 heats and evaporates the refrigerant by underground heat.

  As shown in FIG. 2, the control means 22 first starts a built-in timer at the start of the heating operation (step S1). Here, the control means 22 sets the target discharge temperature of the refrigerant discharged from the compressor 2, the target temperature of the refrigerant on the heat source side heat exchanger 5 side (low pressure side), and the target heating temperature on the load side. Further, during the heating operation, the control means 22 opens and closes the opening of the expansion valve 4 so that the temperature of the refrigerant discharged from the compressor 2 detected by the refrigerant discharge temperature sensor 8 becomes the set target discharge temperature. And the rotational speed of the compressor 2 is controlled so that the temperature of the circulating fluid detected by the return hot water temperature sensor 21 becomes the set target heating temperature.

  And in order to perform quick heat collection of geothermal heat, the control means 22 sets the target rotational speed at the time of start-up of the geothermal circulation pump 13 to the maximum rotational speed (for example, 4000 rpm) which is a predetermined set value. (Step S2). Thereafter, the control means 22 performs start-up control for controlling the rotation speed of the geothermal circulation pump 13 to a maximum rotation speed (for example, 4000 rpm) that is a target rotation speed. Further, the control means 22 sets the low-pressure side refrigerant temperature detected by the refrigerant temperature sensor 9 after a specified time (for example, 2 minutes) has elapsed since completion of the rise of the underground heat circulation pump 13 to the maximum rotational speed. The normal time control for controlling the rotation speed of the underground heat circulation pump 13 is performed so as to reach the target temperature.

  In step S3, the control means 22 determines whether or not the elapsed time from the start of the timer is equal to or longer than a predetermined set time (for example, 30 minutes), and the elapsed time is equal to or longer than the predetermined set time. (No in step S3).

  In step S3, when the elapsed time is equal to or longer than a predetermined set time (Yes in step S3), the control unit 22 shifts the process to step S4, resets the timer, starts again from zero, The process proceeds to step S5.

  In step S5, the control means 22 determines whether or not the number of times the compressor 2 has been activated within the immediately preceding set time (for example, 30 minutes) is greater than or equal to a predetermined set number (for example, 2 times). To do. When it is determined that the number of occurrences of the activation of the compressor 2 within the set time is less than the set number of times (No in step S5), the control unit 22 has the occurrence frequency of at least one of the activation and the stop of the compressor 2 It is determined that the high frequency area has not been reached, and the process returns to step S2. In step S2 in this case, the control means 22 maintains the target rotational speed at the time of start-up of the geothermal circulation pump 13 at the maximum rotational speed (for example, 4000 rpm), or has already reached the upper limit rotational speed (for example, in step S6 described later). If it is set to 2000 rpm), it is determined that the occurrence frequency has shifted from the high frequency region to the outside, and the rotation speed is changed back to the maximum rotation speed (for example, 4000 rpm). Thereby, the required heat collection from underground can be performed more appropriately.

If it is determined in step S5 that the number of occurrences of activation of the compressor 2 within the set time is equal to or greater than the set number (Yes in step S5), the control means 22 determines that the occurrence frequency has reached the high frequency region. The target rotational speed at the time of rising of the underground heat circulation pump 13 is set to an upper limit rotational speed (for example, 2000 rpm) lower than the maximum rotational speed (for example, 4000 rpm) that is a predetermined setting value (step S6). ). Thereafter, when the underground heat circulation pump 13 is activated, the control means 22 controls to increase the rotation speed of the underground heat circulation pump 13 to an upper limit rotation speed (for example, 2000 rpm) which is a target rotation speed. Take control. Further, the control means 22 sets the low-pressure side refrigerant temperature detected by the refrigerant temperature sensor 9 after a specified time (for example, 2 minutes) has elapsed since completion of the rise of the underground heat circulation pump 13 to the upper limit rotation speed. The normal time control for controlling the rotation speed of the underground heat circulation pump 13 is performed so as to reach the target temperature.

  In step S7, the control means 22 determines whether or not the state where the low-pressure side refrigerant temperature detected by the refrigerant temperature sensor 9 is −10 ° C. or lower continues for a predetermined time (for example, 2 minutes) or longer. When it is determined that the state where the low-pressure side refrigerant temperature is −10 ° C. or lower has not continued for a predetermined time or longer (No in step S7), the control unit 22 returns the process to step S3.

  On the other hand, when it is determined in step S7 that the low-pressure side refrigerant temperature is -10 ° C. or lower for a predetermined time or longer (Yes in step S7), the control unit 22 returns the process to step S2. In step S <b> 2 in this case, the control unit 22 changes the target rotational speed at the start of the underground heat circulation pump 13 so as to return from the upper limit rotational speed (for example, 2000 rpm) to the maximum rotational speed (for example, 4000 rpm). Thereby, since heat collection from underground increases, it can prevent that the water | moisture content in the antifreeze liquid which distribute | circulates the fluid flow path of the heat source side heat exchanger 5 begins to freeze, and becomes difficult to flow. When it is determined Yes in step S7, the control unit 22 changes the target rotational speed at the time of rising of the geothermal circulation pump 13 to return to the maximum rotational speed (step S2), and at that time, You may perform control which raises the rotational speed of the underground heat circulation pump 13 to a maximum rotational speed. If it does in this way, the heat collection from underground can be increased rapidly, and it can prevent more easily that the water in the antifreeze liquid which distribute | circulates the fluid flow path of the heat source side heat exchanger 5 begins to freeze, and becomes difficult to flow. .

  Next, with reference to the time chart of FIG. 3, the operation | movement at the time of heating operation of the heat pump apparatus 100 shown in FIG. 1 is demonstrated. FIG. 3 is a time chart showing the movement of each parameter of the heat pump apparatus 100 during the heating operation.

  As shown in FIG. 3, at time t0 to t1, the control means 22 starts up the ground heat circulation pump 13 in order to perform quick heat collection of the ground heat according to the control at the time of start up of the heat pump device 100. Time control is performed. That is, the geothermal circulation pump 13 starts up so as to have a maximum rotational speed (for example, 4000 rpm) that is a preset value as a target rotational speed at the time of rising. Further, the compressor 2 is driven at a rotational speed of, for example, 50 rps so that the temperature of the circulating fluid detected by the return hot water temperature sensor 21 becomes the set target heating temperature. Here, as the heat pump output (heating output) increases, the refrigerant temperature on the low pressure side decreases.

  From time t1 to t2, the control means 22 performs normal time control of the geothermal circulation pump 13 after a specified time (for example, 2 minutes) has elapsed since completion of the rise of the geothermal circulation pump 13 to the maximum rotational speed. Do. That is, the rotation speed of the geothermal circulation pump 13 is controlled so that the refrigerant temperature on the low-pressure side detected by the refrigerant temperature sensor 9 becomes the set target temperature within a range not exceeding the maximum rotation speed. Further, since the temperature of the circulating fluid detected by the return hot water temperature sensor 21 reaches the target heating temperature and the room temperature has sufficiently increased, the rotational speed of the compressor 2 decreases and the refrigerant temperature on the low pressure side increases. .

  At time t <b> 2 to t <b> 3, the control unit 22 performs normal time control of the underground heat circulation pump 13. That is, the rotation speed of the geothermal circulation pump 13 is controlled so that the refrigerant temperature on the low-pressure side detected by the refrigerant temperature sensor 9 becomes the set target temperature within a range not exceeding the maximum rotation speed. Here, the rotational speed of the underground heat circulation pump 13 decreases from the maximum rotational speed, and the refrigerant temperature on the low pressure side decreases. Since the temperature of the circulating fluid detected by the return hot water temperature sensor 21 reaches the target heating temperature and the room temperature is sufficiently high, the rotational speed of the compressor 2 further decreases to the lower limit rotational speed.

  At time t3, the room temperature is maintained sufficiently high, and if the rotational speed of the compressor 2 is reduced below the lower limit rotational speed, the efficiency deteriorates. Therefore, the control means 22 performs control for stopping the driving of the compressor 2. Do. Accordingly, the control means 22 performs control to stop driving of the underground heat circulation pump 13. In addition, the drive of the heating circulation pump 16 is continued and heating by residual heat is performed.

  At time t4, when it is detected that the room temperature has decreased and the temperature of the circulating fluid detected by the return hot water temperature sensor 21 has decreased by a predetermined value or more, the compressor 2 and the geothermal circulation pump 13 are driven again. . Then, at time t4 to t8, here, the same operation as at time t0 to t4 is performed.

  In the time chart of FIG. 3, as shown in time t0 to t7, the number of occurrences of the activation of the compressor 2 within a predetermined set time (for example, 30 minutes) is two times or more (in FIG. 2). Yes in step S5). For this reason, the control means 22 sets the target rotational speed at the time of the rise of the underground heat circulation pump 13 to the upper limit rotational speed (for example, 2000 rpm) lower than the maximum rotational speed (for example, 4000 rpm) (step S6 in FIG. 2). .

  From time t <b> 8 to t <b> 9, the control unit 22 performs start-up control for the underground heat circulation pump 13. That is, the geothermal circulation pump 13 rises so as to have an upper limit rotation speed (for example, 2000 rpm) set as a target rotation speed at the time of rising. In addition, from time t9 to t10, the control means 22 performs normal time for the underground heat circulation pump 13 after a specified time (for example, 2 minutes) has elapsed since the completion of the rise of the underground heat circulation pump 13 to the upper limit rotation speed. Take control. That is, from time t9 to t10, the geothermal circulation pump 13 rotates at a rotational speed so that the low-pressure side refrigerant temperature detected by the refrigerant temperature sensor 9 becomes the set target temperature within a range not exceeding the upper limit rotational speed. Is controlled. Furthermore, the control means 22 performs normal time control about the underground heat circulation pump 13 in the time t10-t11. That is, the rotation speed of the geothermal circulation pump 13 is controlled so that the refrigerant temperature on the low-pressure side detected by the refrigerant temperature sensor 9 becomes the set target temperature within a range not exceeding the upper limit rotation speed. Here, the rotation speed of the underground heat circulation pump 13 decreases from the upper limit rotation speed, and the refrigerant temperature on the low pressure side decreases. Of course, during the time t9 to t11, when the control means 22 performs the normal control for the geothermal circulation pump 13, the low-pressure side refrigerant temperature detected by the refrigerant temperature sensor 9 does not reach the set target temperature. In this case, the rotation speed of the underground heat circulation pump 13 is increased beyond the upper limit rotation speed so that the low-pressure side refrigerant temperature detected by the refrigerant temperature sensor 9 reaches the set target temperature. At time t11, the control means 22 performs control to stop driving the compressor 2 and the underground heat circulation pump 13. Further, at time t12, when it is detected that the temperature of the circulating fluid detected by the return hot water temperature sensor 21 has decreased by a predetermined value or more, the compressor 2 and the underground heat circulation pump 13 are driven again. Then, at time t12 to t16, the same operation as at time t8 to t12 is performed here.

In FIG. 3, in the case of the present embodiment (when the number of occurrences of activation of the compressor 2 during the set time is large, the target rotational speed at the start of the underground heat circulation pump 13 is reduced below the maximum rotational speed). The refrigerant temperature on the low-pressure side and the rotation speed of the underground heat circulation pump 13 are shown by solid lines, and the conventional case as a comparative example (when the target rotation speed at the start of the underground heat circulation pump 13 is always the maximum rotation speed) ) SCOP, the refrigerant temperature on the low pressure side, and the rotational speed of the underground heat circulation pump 13 are indicated by broken lines.
In the present embodiment, as shown at times t8 to t11 and t12 to t15 in FIG. 3, when the heating load is small (at the time of low load), the geothermal circulation pump 13 does not operate at the maximum rotational speed. It can be seen that (= "heating output / (power consumption of the compressor 2 + power consumption of the underground heat circulation pump 13)") is improved.

  As described above, the heat pump device 100 according to the present embodiment detects information indicating the frequency at which at least one of the activation and the stop of the compressor 2 occurs, and the frequency reaches a predetermined high frequency region. When it is determined, the control unit 22 includes a control unit 22 that performs control to lower the target rotation speed when the underground heat circulation pump 13 rises to a maximum rotation speed that is a predetermined set value.

  Therefore, according to the present embodiment, when the heating load is small, the compressor 2 of the heat pump apparatus 100 may repeat the activation, but when the frequency of such activation is high, the underground heat circulation pump 13 The target rotational speed at the time of rising of is lowered from a predetermined set value. In this case, since the underground heat circulation pump 13 does not reach the maximum rotation speed that is a predetermined set value at the time of startup, the overall efficiency of the heat pump device 100 is improved. That is, it is possible to provide the heat pump device 100 capable of performing efficient heating operation even when the load is small.

  Next, with reference to FIGS. 4 to 8, other embodiments of the present invention will be described with a focus on differences from the embodiments shown in FIGS. 1 to 3, and common points will be described. Omitted as appropriate.

  FIG. 4 is a schematic configuration diagram of a heat pump device 100a according to another embodiment of the present invention. FIG. 5 is a schematic configuration diagram illustrating a state of the heat pump device 100a during heating operation. FIG. 6 is a schematic configuration diagram illustrating a state of the heat pump device 100a during the cooling operation. That is, the heat pump device 100a according to the present embodiment is a geothermal heat pump air conditioner that uses geothermal heat, and is a hot water circulation type geothermal heat pump device that uses geothermal heat in the above-described FIG. It is different from the heat pump apparatus 100 shown.

  As shown in FIG. 4, the heat pump device 100 a according to this embodiment includes an indoor unit 31 for air conditioning, and the indoor unit 31 cools or heats the air-conditioned space. The refrigerant pipe 6 is provided with a four-way valve 25 that switches between heating and cooling by changing the flow direction of the refrigerant in the refrigerant pipe 6. The load-side heat exchanger 3 performs heat exchange between the air sent by the operation of the blower fan 32 and the refrigerant. A remote controller 23 is installed in the air-conditioned space that is cooled or heated by the indoor unit 31. In addition, the code | symbol 33 in FIG. 4 is a room temperature sensor which detects the temperature (room temperature) of the indoor air which is an air-conditioned space. The indoor unit 31 is provided with an indoor unit control unit 24. The indoor unit control unit 24 receives a detection signal from the room temperature sensor 33 and an operation signal from the remote controller 23, and the control unit 22 of the heat pump unit 1. Communicate.

  When an instruction to heat (heat) the air-conditioned space is given from the remote controller 23, the four-way valve is set so that the refrigerant discharged from the compressor 2 flows toward the load-side heat exchanger 3, as shown in FIG. 25 is switched. And the drive of the compressor 2 and the underground heat circulation pump 13 is started, and while making the heat source side heat exchanger 5 function as an evaporator, the load side heat exchanger 3 is functioned as a condenser, and the load side is heated. Heating operation as load operation is performed. During the heating operation, in the load-side heat exchanger 3, heat exchange is performed between the high-temperature and high-pressure refrigerant discharged from the compressor 2 and the air sent by the blower fan 32, and the load-side heat exchanger 3 is heated. The air is sent to the air-conditioned space and heats the air-conditioned space that has been instructed by the remote controller.

  On the other hand, when an instruction to cool (cool) the air-conditioned space is given from the remote controller 23, 4 4 so that the refrigerant discharged from the compressor 2 flows toward the heat source side heat exchanger 5 as shown in FIG. The direction valve 25 is switched. And the drive of the compressor 2 and the underground heat circulation pump 13 is started, and while making the load side heat exchanger 3 function as an evaporator, the heat source side heat exchanger 5 is functioned as a condenser, and cools a load side. Cooling operation as load operation is performed. During the cooling operation, the load-side heat exchanger 3 performs heat exchange between the low-temperature and low-pressure refrigerant discharged from the expansion valve 4 and the air sent by the blower fan 32, and is cooled by the load-side heat exchanger 3. The air is sent to the air-conditioned space and cools the air-conditioned space that has been instructed by the remote controller.

  The operation of the heat pump device 100a shown in FIG. 4 during the heating operation (see FIG. 5) is substantially the same as the operation shown in FIGS. 2 and 3 during the heating operation of the heat pump device 100 shown in FIG. Omitted.

Next, with reference to the flowchart of FIG. 7, operation | movement of the underground heat circulation pump 13 mainly at the time of the cooling operation (refer FIG. 6) of the heat pump apparatus 100a shown in FIG. 4 is demonstrated.
FIG. 7 is a flowchart showing the contents of processing for setting the target rotational speed when the underground heat circulation pump 13 rises during cooling operation.

  When an instruction to cool (cool) the air-conditioned space by the indoor unit 31 is given from the remote controller 23, and the instruction is sent to the control means 22 via the indoor unit control means 24, the control means 22 is connected to the compressor 2 and the underground. The driving of the heat circulation pump 13 is started, and the cooling operation as the load operation is started. When the cooling operation is started, the load-side heat exchanger 3 exchanges heat between the air sent by the operation of the blower fan 32 and the low-temperature and low-pressure refrigerant discharged from the expansion valve 4, and the cooled air becomes the air-conditioned space. In the heat source side heat exchanger 5, the antifreeze circulated by the geothermal circulation pump 13 and the high-temperature and high-pressure refrigerant discharged from the compressor 2 are heat-exchanged. The antifreeze with the heat is supplied to the underground heat exchanger 10 and is radiated to the ground by the underground heat exchanger 10.

  As shown in FIG. 7, the control means 22 first starts a built-in timer at the start of the cooling operation (step S11). Here, the control means 22 sets the target discharge temperature of the refrigerant discharged from the compressor 2, the target temperature of the refrigerant on the heat source side heat exchanger 5 side (high pressure side), and the target cooling temperature on the load side. Further, during the cooling operation, the control means 22 opens and closes the opening of the expansion valve 4 so that the temperature of the refrigerant discharged from the compressor 2 detected by the refrigerant discharge temperature sensor 8 becomes the set target discharge temperature. And the rotational speed of the compressor 2 is controlled so that the room temperature detected by the room temperature sensor 33 becomes the set target cooling temperature (set temperature set by the remote controller 23).

  And the control means 22 makes the target rotational speed at the time of the rise of the underground heat circulation pump 13 the maximum rotational speed (for example, 4000 rpm) which is a predetermined setting value in order to perform quick heat radiation to the ground. Set (step S12). Thereafter, the control means 22 performs start-up control for controlling the rotation speed of the geothermal circulation pump 13 to a maximum rotation speed (for example, 4000 rpm) that is a target rotation speed. Further, the control means 22 sets the high-pressure side refrigerant temperature detected by the refrigerant temperature sensor 9 after a lapse of a specified time (for example, 2 minutes) from the completion of the rise of the underground heat circulation pump 13 to the maximum rotational speed. The normal time control for controlling the rotation speed of the underground heat circulation pump 13 is performed so as to reach the target temperature.

  In step S13, the control means 22 determines whether or not the elapsed time from the start of the timer is equal to or longer than a predetermined set time (for example, 30 minutes), and the elapsed time is equal to or longer than the predetermined set time. (No in step S13).

  In step S13, when the elapsed time is equal to or longer than a predetermined set time (Yes in step S13), the control unit 22 shifts the process to step S14, resets the timer, starts again from zero, The process proceeds to step S15.

  In step S15, the control means 22 determines whether or not the number of times that the compressor 2 has been activated within the immediately preceding set time (for example, 30 minutes) is greater than or equal to a predetermined set number (for example, 2 times). To do. When it is determined that the number of occurrences of activation of the compressor 2 within the set time is less than the set number of times (No in step S15), the control means 22 has a frequency of occurrence of at least one of activation and stop of the compressor 2. It is determined that the high frequency area has not been reached, and the process returns to step S12. In step S12 in this case, the control means 22 maintains the target rotational speed at the time of start-up of the geothermal circulation pump 13 at the maximum rotational speed (for example, 4000 rpm) or has already reached the upper limit rotational speed (for example, in step S16 described later). If it is set to 2000 rpm), it is determined that the occurrence frequency has shifted from the high frequency region to the outside, and the rotation speed is changed back to the maximum rotation speed (for example, 4000 rpm). Thereby, necessary heat radiation to the ground can be performed more appropriately.

If it is determined in step S15 that the number of occurrences of activation of the compressor 2 within the set time is equal to or greater than the set number (Yes in step S15), the control means 22 determines that the occurrence frequency has reached the high frequency region. The target rotational speed at the time of rising of the underground heat circulation pump 13 is set to an upper limit rotational speed (for example, 2000 rpm) lower than the maximum rotational speed (for example, 4000 rpm) that is a predetermined set value (step S16). ). Thereafter, when the underground heat circulation pump 13 is activated, the control means 22 controls to increase the rotation speed of the underground heat circulation pump 13 to an upper limit rotation speed (for example, 2000 rpm) which is a target rotation speed. Take control. Further, the control means 22 sets the high-pressure side refrigerant temperature detected by the refrigerant temperature sensor 9 after a lapse of a specified time (for example, 2 minutes) from the completion of the rise of the underground heat circulation pump 13 to the upper limit rotation speed. The normal time control for controlling the rotation speed of the underground heat circulation pump 13 is performed so as to reach the target temperature.
After step S16, the control means 22 returns the process to step S13.

  Next, with reference to the time chart of FIG. 8, the operation | movement at the time of air_conditionaing | cooling operation (refer FIG. 6) of the heat pump apparatus 100a shown in FIG. 4 is demonstrated. FIG. 8 is a time chart showing the movement of each parameter of the heat pump device 100a during the cooling operation.

  As shown in FIG. 8, at time t <b> 0 to t <b> 1, in order to perform quick heat release to the ground according to the control at the time of rising of the heat pump device 100 a, the control means 22 Take control. That is, the geothermal circulation pump 13 starts up so as to have a maximum rotational speed (for example, 4000 rpm) that is a preset value as a target rotational speed at the time of rising. Further, the compressor 2 is driven at a rotational speed of, for example, 50 rps so that the indoor temperature detected by the room temperature sensor 33 becomes the set target cooling temperature. Here, as the heat pump output (cooling output) increases, the refrigerant temperature on the high pressure side increases.

  From time t1 to t2, the control means 22 performs normal time control of the geothermal circulation pump 13 after a specified time (for example, 2 minutes) has elapsed since completion of the rise of the geothermal circulation pump 13 to the maximum rotational speed. Do. That is, the rotation speed of the geothermal circulation pump 13 is controlled so that the refrigerant temperature on the high-pressure side detected by the refrigerant temperature sensor 9 becomes the set target temperature within a range not exceeding the maximum rotation speed. Further, since the room temperature detected by the room temperature sensor 33 has reached the target cooling temperature, the rotational speed of the compressor 2 is reduced and the refrigerant temperature on the high pressure side is reduced.

  At time t <b> 2 to t <b> 3, the control unit 22 performs normal time control of the underground heat circulation pump 13. That is, the rotation speed of the geothermal circulation pump 13 is controlled so that the refrigerant temperature on the high-pressure side detected by the refrigerant temperature sensor 9 becomes the set target temperature within a range not exceeding the maximum rotation speed. Here, the rotation speed of the underground heat circulation pump 13 decreases from the maximum rotation speed, and the refrigerant temperature on the high-pressure side increases. Since the room temperature detected by the room temperature sensor 33 reaches the target cooling temperature and the room temperature is sufficiently low, the rotation speed of the compressor 2 further decreases to the lower limit rotation speed.

  At time t3, the room temperature is maintained sufficiently low, and if the rotational speed of the compressor 2 is reduced below the lower limit rotational speed, the efficiency deteriorates. Therefore, the control means 22 performs control for stopping the driving of the compressor 2. Do. Accordingly, the control means 22 performs control to stop driving of the underground heat circulation pump 13.

  When the room temperature rises at time t4 and it is detected that the room temperature detected by the room temperature sensor 33 has risen by a predetermined value or more, the compressor 2 and the underground heat circulation pump 13 are driven again. Then, at time t4 to t8, here, the same operation as at time t0 to t4 is performed.

  In the time chart of FIG. 8, as shown in time t0 to t7, the number of occurrences of the activation of the compressor 2 within a predetermined set time (for example, 30 minutes) is two times or more (in FIG. 7). Yes in step S15). For this reason, the control means 22 sets the target rotational speed at the time of the rise of the underground heat circulation pump 13 to the upper limit rotational speed (for example, 2000 rpm) lower than the maximum rotational speed (for example, 4000 rpm) (step S16 in FIG. 7). .

  From time t <b> 8 to t <b> 9, the control unit 22 performs start-up control for the underground heat circulation pump 13. That is, the geothermal circulation pump 13 rises so as to have an upper limit rotation speed (for example, 2000 rpm) set as a target rotation speed at the time of rising. In addition, from time t9 to t10, the control means 22 performs normal time for the underground heat circulation pump 13 after a specified time (for example, 2 minutes) has elapsed since the completion of the rise of the underground heat circulation pump 13 to the upper limit rotation speed. Take control. That is, the rotation speed of the geothermal circulation pump 13 is controlled so that the refrigerant temperature on the high-pressure side detected by the refrigerant temperature sensor 9 becomes the set target temperature within a range not exceeding the upper limit rotation speed. Furthermore, the control means 22 performs normal time control about the underground heat circulation pump 13 in the time t10-t11. That is, the rotation speed of the geothermal circulation pump 13 is controlled so that the refrigerant temperature on the high-pressure side detected by the refrigerant temperature sensor 9 becomes the set target temperature within a range not exceeding the upper limit rotation speed. Here, the rotational speed of the underground heat circulation pump 13 decreases from the upper limit rotational speed, and the refrigerant temperature on the high-pressure side increases. Of course, when the control means 22 performs the normal control for the underground heat circulation pump 13 during the time t9 to t11, the high-pressure side refrigerant temperature detected by the refrigerant temperature sensor 9 does not reach the set target temperature. The rotational speed of the underground heat circulation pump 13 is increased beyond the upper limit rotational speed so that the high-pressure side refrigerant temperature detected by the refrigerant temperature sensor 9 reaches the set target temperature. At time t11, the control means 22 performs control to stop driving the compressor 2 and the underground heat circulation pump 13. Further, at time t12, when it is detected that the room temperature detected by the room temperature sensor 33 has increased by a predetermined value or more, the compressor 2 and the underground heat circulation pump 13 are driven again. Then, at time t12 to t16, the same operation as at time t8 to t12 is performed here.

In FIG. 8, SCOP in the case of the present embodiment (when the target rotation speed at the start-up of the geothermal circulation pump 13 is reduced below the maximum rotation speed when the number of occurrences of the compressor 2 during the set time is large). The refrigerant temperature on the high-pressure side and the rotation speed of the underground heat circulation pump 13 are shown by solid lines, and the conventional case as a comparative example (when the target rotation speed at the start of the underground heat circulation pump 13 is always the maximum rotation speed) ) SCOP, the refrigerant temperature on the high pressure side, and the rotational speed of the underground heat circulation pump 13 are indicated by broken lines.
In the present embodiment, as shown at times t8 to t11 and t12 to t15 in FIG. 8, when the cooling load is small (low load), the geothermal circulation pump 13 does not operate at the maximum rotational speed. It can be seen that (= "cooling output / (power consumption of the compressor 2 + power consumption of the underground heat circulation pump 13)") is improved.

  As described above, the heat pump apparatus 100a shown in FIG. 4 can perform an efficient load operation even when the load is small, similarly to the heat pump apparatus 100 shown in FIG.

  As mentioned above, although this invention was demonstrated based on embodiment, this invention is not limited to the structure described in the said embodiment, The combination thru | or selecting suitably the structure described in the said embodiment is included. The configuration can be changed as appropriate without departing from the spirit of the invention. In addition, a part of the configuration of the embodiment can be added, deleted, and replaced.

  For example, the information indicating the frequency of occurrence of at least one of activation and stop of the compressor 2 is the number of occurrences of activation of the compressor 2 within a predetermined set time in the above embodiment. However, the present invention is not limited to this. For example, it may be the number of times that the compressor 2 stops within a predetermined set time, or the start and stop of the compressor 2 within a predetermined set time. This may be the number of times that the combination (start / stop) occurs.

  Further, the information indicating the frequency at which at least one of the start and stop of the compressor 2 is generated is the generation cycle of the start or stop of the compressor 2, and the high frequency area is a set cycle in which the generation cycle is determined in advance. The area may be (for example, 15 minutes) or less. In this way, it is possible to determine whether or not the frequency of occurrence of at least one of starting and stopping of the compressor 2 has reached the high-frequency region without requiring waiting for the elapse of a preset time as the check period. Judgment can be made. Therefore, for example, as soon as the period between the previous activation of the compressor 2 and the current activation (occurrence period of the activation) becomes equal to or less than the set period, the target rotational speed when the underground heat circulation pump 13 is started up Can be made lower than the maximum rotation speed, it is possible to respond more quickly and to perform more efficient load operation. Note that the value of the set period described above can be changed as appropriate.

  Further, the control means 22 detects information indicating the frequency at which at least one of the activation and stop of the geothermal circulation pump 13 occurs instead of the frequency at which at least one of the activation and stop of the compressor 2 occurs, It may be determined whether or not the frequency has reached a predetermined high frequency region.

  In the embodiment, only one underground heat exchanger 10 is installed in the ground. However, a plurality of underground heat exchangers 10 may be installed in the ground. The exchangers 11 may be connected in parallel to each other or may be connected in series.

  Moreover, in the said embodiment, the underground heat exchanger 10 shall be installed in the ground, and the underground heat exchanger 10 is directly embed | buried in the ground and is collecting ground heat, In the case of heating operation, for example, in the case of heating operation, the one that collects heat from the well water heated by the underground heat is also included in the one that installs the underground heat exchanger 10 in the underground.

2 Compressor 3 Load side heat exchanger 4 Expansion valve (pressure reduction means)
5 Heat source side heat exchanger 6 Refrigerant piping 7 Heat pump circuit 10 Ground heat exchanger (heat source)
11 Underground heat pipe (heat medium pipe)
12 Ground heat circulation circuit (heat source side circulation circuit)
13 Geothermal circulation pump (heat source side circulation pump)
22 Control means 100, 100a Heat pump device

Claims (4)

A heat pump circuit in which a compressor, a load-side heat exchanger, a decompression unit, and a heat source-side heat exchanger are connected in an annular shape with refrigerant piping;
The heat source side heat exchanger, and a heat source side circulation circuit in which the heat source is annularly connected by a heat medium pipe;
A heat source side circulation pump for circulating a heat medium in the heat source side circulation circuit;
When detecting information indicating the frequency of occurrence of at least one of activation and stop of at least one of the compressor and the heat source side circulation pump and determining that the frequency has reached a predetermined high frequency region, the heat source Control means for controlling the target rotational speed at the time of rising of the side circulation pump to be lower than a predetermined set value;
A heat pump device comprising:   The information is the number of occurrences of at least one of starting and stopping of the compressor and the heat source side circulation pump within a predetermined set time, and the high frequency region has the predetermined number of times. The heat pump device according to claim 1, wherein the heat pump device is a region that exceeds a set number of times.   The information is a generation cycle of activation or stop of at least one of the compressor and the heat source side circulation pump, and the high-frequency region is a region in which the generation cycle is equal to or less than a predetermined set cycle. The heat pump device according to claim 1, wherein   The control means performs control to return the target rotation speed at the time of rising of the heat source side circulation pump to the set value when it is determined that the frequency has shifted from the inside of the high frequency region to the outside. The heat pump device according to any one of claims 1 to 3.

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