Refrigeration cycle device and control device

Abstract

To provide a refrigeration cycle device that can reduce noise without increase in cost, and to provide a control device.SOLUTION: A refrigeration cycle device includes a heat source unit, an indoor unit, and a control device. The heat source unit or the indoor unit includes a plurality of driving sources of which frequency characteristics of emitted sound are equal to one another. The control device includes: an operation control part for outputting a control signal for controlling the plurality of driving sources; and a noise reducing part for providing time deviation to at least one of the control signals of the driving sources so as to cancel the noise that is caused by the driving of the plurality of driving sources.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a refrigeration cycle device including a plurality of drive sources and a control device that controls the plurality of drive sources. [Background technology]

[0002] Large refrigeration cycle devices, such as commercial package air conditioners or chillers, are equipped with multiple drive sources, including compressors and fans, of the same type. Drive sources of the same type often use identical components, and the frequency characteristics of the noise they generate are similar. In the case of such refrigeration cycle devices, because multiple drive sources are installed inside the device, there is a problem that the operating noise is louder than devices with a single drive source. In particular, when multiple drive sources are of the same type, the phases of the sounds emitted from the drive sources are aligned, and the sound waves are added together, resulting in a significant increase in noise levels.

[0003] To address this issue, a conventional approach is to attach sound-absorbing material to the drive source to reduce noise. Patent Document 1 also proposes a technology in which a speaker is provided in the device and generates sound of an opposite phase from the speaker to cancel out the sound from the sound source. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 03-53698 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when attaching sound-absorbing material to the drive source as in the above-mentioned conventional technology, and when providing a speaker to generate anti-phase sound, the cost of additional parts such as the sound-absorbing material and speaker increases the product cost.

[0006] The present disclosure is intended to solve the above-mentioned problems, and aims to provide a refrigeration cycle device and a control device that can achieve low noise without increasing costs. [Means for solving the problem]

[0007] The refrigeration cycle device according to the present disclosure is a refrigeration cycle device comprising a heat source unit, an indoor unit, and a control device, wherein the heat source unit or the indoor unit has a plurality of drive sources that generate sounds with similar frequency characteristics, and the control device has an operation control unit that outputs control signals for controlling the plurality of drive sources, and a sound reduction processing unit that imparts a time delay to the control signal of at least one of the plurality of drive sources so that sounds resulting from operation of the plurality of drive sources are canceled out.

[0008] The control device according to the present disclosure is a control device that controls multiple drive sources that generate sounds with similar frequency characteristics, and includes an operation control unit that outputs control signals for controlling the multiple drive sources, and a sound reduction processing unit that imparts a time delay to the control signal of at least one of the multiple drive sources so that sounds resulting from the operation of the multiple drive sources are canceled out. [Effects of the Invention]

[0009] According to the present disclosure, noise reduction can be achieved without increasing costs by providing a time lag to the control signals of the drive sources so that the sounds emitted by the multiple drive sources cancel each other out. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic configuration diagram of a refrigeration cycle device according to a first embodiment. [Figure 2] 1 is a control block diagram of a refrigeration cycle device according to a first embodiment. [Figure 3] FIG. 3 is a diagram illustrating the arrangement of drive sources in the heat source unit according to the first embodiment. [Figure 4] 10A and 10B are diagrams illustrating operating noise generated in a heat source unit of a refrigeration cycle device in a comparative example. [Figure 5] 3 is a diagram illustrating the operating noise generated in the heat source unit of the refrigeration cycle device in the first embodiment. FIG. [Figure 6] FIG. 10 is a diagram illustrating the arrangement of peripheral components in a heat source unit according to embodiment 3. [Figure 7] FIG. 10 is a diagram illustrating the arrangement of drive sources in a heat source unit according to embodiment 4. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of a refrigeration cycle apparatus 100 and a control device 5 according to the present disclosure will be described with reference to the drawings. In each drawing, components denoted with the same reference numerals are identical or equivalent components, and this is common throughout the specification. Note that the relative dimensional relationships or shapes of each component in each drawing may differ from the actual ones. Also, while some drawings depict front-to-back, up-down, and left-to-right directions, these are defined for the purpose of explanation and do not limit the orientation of each component.

[0012] Embodiment 1 FIG. 1 is a schematic configuration diagram of a refrigeration cycle apparatus 100 according to the first embodiment. The refrigeration cycle apparatus 100 according to the first embodiment is a heat pump chiller that performs air conditioning using chilled or hot water. As shown in FIG. 1, the refrigeration cycle apparatus 100 includes a heat source unit 1, a plurality of indoor units 2a and 2b, and a control device 5. Although FIG. 1 shows the refrigeration cycle apparatus 100 having two indoor units 2a and 2b, the number of indoor units may be one, or three or more.

[0013] The heat source unit 1 of this embodiment has two refrigerant circuits 10a and 10b, outdoor fans 16a and 16b, a water heat exchanger 60, and a pump 80. The water heat exchanger 60 is a component of both the refrigerant circuits 10a and 10b and the heat medium circuit 20.

[0014] The refrigerant circuit 10a is composed of a compressor 11a, a four-way valve 12a, an outdoor heat exchanger 13a, an outdoor expansion valve 14a, a water heat exchanger 60, and an accumulator 15a. The refrigerant circuit 10b is composed of a compressor 11b, a four-way valve 12b, an outdoor heat exchanger 13b, an outdoor expansion valve 14b, a water heat exchanger 60, and an accumulator 15b. The components of the refrigerant circuit 10a are of the same type of equipment and have the same configuration and function as the components of the refrigerant circuit 10b. The following describes the components of the refrigerant circuit 10a as a representative example.

[0015] The compressor 11a is an inverter compressor whose capacity (the amount of refrigerant delivered per unit time) is changed by arbitrarily changing the operating frequency (number of rotations) of the compressor 11a using, for example, an inverter circuit (not shown). The operating frequency of the compressor 11a is controlled by a control signal from the control device 5.

[0016] The four-way valve 12a switches the refrigerant flow path depending on the operation mode of the indoor units 2a and 2b. For example, in the cooling operation mode, the four-way valve 12a switches the refrigerant flow path so that the high-temperature, high-pressure refrigerant discharged from the compressor 11a flows into the outdoor heat exchanger 13a. In the heating operation mode, the four-way valve 12a switches the refrigerant flow path so that the high-temperature, high-pressure refrigerant discharged from the compressor 11a flows into the water heat exchanger 60.

[0017] The outdoor heat exchanger 13a is a fin-tube heat exchanger that exchanges heat between the refrigerant and the outside air. In a heating operation (heating operation) for heating water, the outdoor heat exchanger 13a functions as an evaporator, exchanging heat between the low-pressure refrigerant that flows in from the outdoor expansion valve 14a side and the air, thereby evaporating the refrigerant. In a cooling operation (cooling operation) for cooling water, the outdoor heat exchanger 13a functions as a condenser, exchanging heat between the high-pressure refrigerant that flows in from the compressor 11a side and the air, thereby condensing and liquefying the refrigerant.

[0018] The outdoor fan 16a sends air to the outdoor heat exchanger 13a to promote heat exchange between the refrigerant and the air. The rotation speed (air volume) of the outdoor fan 16a is controlled by a control signal from the control device 5. In FIG. 1, the outdoor heat exchanger 13a and the outdoor fan 16a are in one-to-one correspondence, but multiple outdoor fans 16a may be provided for one outdoor heat exchanger 13a. The outdoor fans 16a and 16b are the same type of fan.

[0019] The water heat exchanger 60 is a plate-type heat exchanger or a double-pipe heat exchanger that exchanges heat between the heat medium flowing through the heat medium circuit 20 and the refrigerant flowing through the refrigerant circuits 10a and 10b. During heating operation, for example, the water heat exchanger 60 functions as a condenser, exchanging heat between the refrigerant flowing in from the compressors 11a and 11b side and water, condensing the refrigerant to liquefy or convert it to a two-phase gas-liquid state, and heating the water. During cooling operation, on the other hand, it functions as an evaporator, exchanging heat between the refrigerant flowing in from the outdoor expansion valves 14a and 14b side and water, evaporating the refrigerant to cool the water.

[0020] The outdoor expansion valve 14a reduces the pressure of the refrigerant passing through the water heat exchanger 60 and expands it. The outdoor expansion valve 14a in this embodiment is an electronic expansion valve that changes its opening based on instructions from the control device 5, or a temperature-sensitive expansion valve that changes its opening based on the temperature of the refrigerant. The accumulator 15a is provided on the suction side of the compressor 11a and stores surplus refrigerant in the refrigerant circuit 10a.

[0021] The pump 80 is one of the devices that make up the heat medium circuit 20. The pump 80 sucks water in the heat medium circuit 20, applies pressure to it, and sends it out to circulate it. The operation frequency of the pump 80 is controlled by a control signal from the control device 5.

[0022] The indoor units 2a and 2b are units that send conditioned air to an indoor space that is the target of air conditioning. The indoor units 2a and 2b may be installed in the same space or in different spaces. As shown in FIG. 1 , the indoor unit 2a of this embodiment has an indoor heat exchanger 21a, a flow rate adjustment valve 22a, and an indoor fan 23a. The indoor unit 2b of this embodiment has an indoor heat exchanger 21b, a flow rate adjustment valve 22b, and an indoor fan 23b. The indoor heat exchangers 21a and 21b and the flow rate adjustment valves 22a and 22b are devices that make up the heat medium circuit 20. The components of the indoor unit 2a are the same type of devices with the same configurations and functions as the components of the indoor unit 2b. Below, each component of the indoor unit 2a will be described as a representative.

[0023] The indoor heat exchanger 21a is a fin-tube heat exchanger that exchanges heat between indoor air and water in the indoor space. During cooling operation, cold water passes through the heat transfer tubes of the indoor heat exchanger 21a to cool the indoor space. On the other hand, during heating operation, hot water passes through the heat transfer tubes of the indoor heat exchanger 21a to heat the indoor space.

[0024] The flow rate control valve 22a is, for example, a two-way valve capable of controlling the valve opening (opening area). By adjusting its opening, the flow rate control valve 22a controls the flow rate of water flowing into and out of the indoor heat exchanger 21a, allowing the indoor heat exchanger 21a to exchange heat at a quantity appropriate to the indoor thermal load. When the indoor heat exchanger 21a does not need to exchange heat with the thermal load, such as when the indoor heat exchanger 21a is stopped or thermostat is turned off, the flow rate control valve 22a can fully close the valve to stop the supply of water to and from the indoor heat exchanger 21a. In FIG. 1, the flow rate control valve 22a is installed in the piping on the water inlet side of the indoor heat exchanger 21a, but this is not limiting. For example, the flow rate control valve 22a may be installed on the water outlet side of the indoor heat exchanger 21a.

[0025] The indoor fan 23a sends air to the indoor heat exchanger 21a to promote heat exchange between the water and the air. The rotation speed (air volume) of the indoor fan 23a is controlled by a control signal from the control device 5.

[0026] The refrigeration cycle apparatus 100 also includes a plurality of sensors. Specifically, the heat source unit 1 includes an outdoor air temperature sensor 31 that measures the outdoor air temperature, which is the temperature of the outdoor space in which the heat source unit 1 is installed. The indoor units 2a and 2b also include an indoor temperature sensor 32a and an indoor temperature sensor 32b, respectively, that measure the indoor temperature, which is the temperature of the space to be air-conditioned. The outdoor air temperature sensor 31 and the indoor temperature sensors 32a and 32b are configured with, for example, a thermistor or an infrared sensor. The outdoor air temperature measured by the outdoor air temperature sensor 31 and the indoor temperatures measured by the indoor temperature sensors 32a and 32b are transmitted to the control device 5.

[0027] The refrigeration cycle apparatus 100 may include a temperature sensor or pressure sensor other than the above-mentioned temperature sensors. For example, the refrigeration cycle apparatus 100 may include a sensor that measures the temperature of water flowing through the heat medium circuit 20, a sensor that measures the temperature or pressure of the refrigerant discharged from or sucked into the compressors 11a and 11b, or a sensor that measures the temperature of the refrigerant flowing through the outdoor heat exchangers 13a and 13b.

[0028] The control device 5 controls the operation of the heat source unit 1 and the multiple indoor units 2a and 2b. The control device 5 is composed of a computer equipped with a memory for storing data and programs required for control and a processor such as a CPU for executing the programs, a dedicated processing circuit such as an ASIC or FPGA, or both. Note that in FIG. 1, the control device 5 is provided separately from the heat source unit 1 and the indoor units 2a and 2b, but the control device 5 may be provided in any of the units, or each unit may be provided with its own control device 5.

[0029] Fig. 2 is a control block diagram of the refrigeration cycle apparatus 100 according to the first embodiment. As shown in Fig. 2, the control device 5 of the refrigeration cycle apparatus 100 includes an operation control unit 51, a sound reduction processing unit 52, and a storage unit 53. The operation control unit 51 and the sound reduction processing unit 52 are functional units that are realized by a processor such as a CPU constituting the control device 5 executing a program. Alternatively, at least one of the operation control unit 51 and the sound reduction processing unit 52 may be realized by a processing circuit such as an ASIC or an FPGA.

[0030] The operation control unit 51 controls the heat source unit 1 and the multiple indoor units 2a and 2b to perform cooling operation and heating operation. Specifically, the operation control unit 51 generates and outputs control signals for controlling at least any of the operating frequency of the compressors 11a and 11b, the switching of the four-way valves 12a and 12b, the opening of the outdoor expansion valves 14a and 14b, the opening of the flow control valves 22a and 22b, the rotation speed of the outdoor fans 16a and 16b, and the rotation speed of the indoor fans 23a and 23b, based on the setting of the operation mode and the set temperature input by the user and the measurement results of the outdoor air temperature sensor 31 and the indoor temperature sensors 32a and 32b.

[0031] The sound reduction processing unit 52 performs processing to reduce the operating noise of the refrigeration cycle apparatus 100. The sound reduction processing performed by the sound reduction processing unit 52 will be described later.

[0032] The storage unit 53 is, for example, a non-volatile semiconductor memory such as a ROM or a flash memory, a volatile semiconductor memory such as a RAM, an HDD, or an SSD, etc. The storage unit 53 stores various data such as programs executed by the control device 5 and thresholds used in executing the programs.

[0033] Next, the sound reduction process by the sound reduction processor 52 of this embodiment will be described. Generally, a drive source equipped with a motor or the like generates sound due to vibration during operation. The sound reduction processor 52 of this embodiment reduces sound generated from multiple drive sources of the same type. In the case of the refrigeration cycle apparatus 100 of this embodiment, the compressors 11a and 11b, the outdoor fans 16a and 16b, or the indoor fans 23a and 23b are multiple drive sources of the same type. In this disclosure, "same type of drive source" refers to a drive source that generates sounds with similar frequency characteristics (which do not have to be strictly identical). Below, a case where the sound reduction processor 52 reduces the sound generated by the compressors 11a and 11b will be described.

[0034] FIG. 3 is a diagram illustrating the arrangement of the driving sources in the heat source unit 1 according to the first embodiment. As shown in FIG. 3, compressors 11a and 11b, which are the driving sources, are arranged side by side horizontally inside the housing of the heat source unit 1. The volume of the sound from the heat source unit 1 varies depending on the position from which the sound is heard, i.e., the distance from the compressors 11a and 11b, which are the sound sources. In this embodiment, as shown in FIG. 3, a case will be described as an example in which the sound from the heat source unit 1 is reduced at a reference position P on the front side of the heat source unit 1. The reference position P is, for example, a sound evaluation position at which the noise from the heat source unit 1 is evaluated.

[0035] Fig. 4 is a diagram illustrating the operating noise generated in the heat source unit of a refrigeration cycle device in a comparative example. The comparative example is an example of a refrigeration cycle device having the same configuration as the refrigeration cycle device 100 of the present embodiment, but without noise reduction processing by the noise reduction processing unit 52. Fig. 4(a) is a time history waveform of the sound of the first drive source, Fig. 4(b) is a time history waveform of the sound of the second drive source, and Fig. 4(c) is a time history waveform of the sound of the heat source unit of the comparative example at reference position P in Fig. 3. In Fig. 4, the sound of the first drive source is indicated by a dashed line, the sound of the second drive source is indicated by a dashed double-dashed line, and the sound of the heat source unit is indicated by a thick line.

[0036] The first drive source in the comparative example is the same compressor as compressor 11a in this embodiment, and the second drive source is the same compressor as compressor 11b in this embodiment, and they are arranged as shown in Figure 3. The first drive source and the second drive source are the same type of drive source and have equivalent frequency characteristics of the sounds they generate, so the phases of the sounds from the first drive source and the second drive source are aligned. As a result, as shown in Figure 4(c), the operating noise of the heat source unit 1 increases significantly due to the addition of sound waves from the first drive source and the second drive source.

[0037] In contrast, in the refrigeration cycle apparatus 100 of this embodiment, the sound reduction processing unit 52 cancels out the sounds of the multiple drive sources to reduce the operating sound of the heat source unit 1. Specifically, when the compressor 11a is the first drive source and the compressor 11b is the second drive source, if the phase of the sound of the compressor 11a and the phase of the sound of the compressor 11b are shifted by half a wavelength (if they are in opposite phase), the sounds can be canceled out. Therefore, the sound reduction processing unit 52 imparts a time delay τ(s) to the control signal for the compressor 11a generated by the operation control unit 51, thereby generating a difference in operation between the compressors 11a and 11b. It is assumed that the operating frequency of the compressor 11a is the same as the operating frequency of the compressor 11b.

[0038] The sound reduction processor 52 calculates the time lag τ based on the following equation (1). τ=1 / (2f)-(δa-δb) / v ···(1) Here, δa is the distance (m) from the reference position P to the compressor 11a, and δb is the distance (m) from the reference position P to the compressor 11b. v is the sound speed (m / s) of the ambient gas, and f is the frequency (Hz) of the peak noise of the compressors 11a and 11b.

[0039] Distances δa and δb are determined in advance based on the arrangement of each device within the housing of heat source unit 1, and are stored in memory unit 53. Because the ambient gas in heat source unit 1 is air, the sound speed v is the speed of sound in air (approximately 340.5 m / s). Because compressors 11a and 11b are the same type of compressor, they have the same peak noise frequency f. The peak noise frequency f of compressors 11a and 11b is the frequency of the sound generated from compressors 11a and 11b operating at the maximum operating frequency specified in the specifications, and is stored in memory unit 53 in advance.

[0040] The sound reduction processing unit 52 imparts a time lag τ to the control signal for compressor 11a generated by the operation control unit 51. As a result, a time lag τ occurs between the control signal for compressor 11a and the control signal for compressor 11b, causing a difference in the operation timing between compressor 11a and compressor 11b. FIG. 5 is a diagram illustrating the operating noise generated in the heat source unit 1 of the refrigeration cycle apparatus 100 in embodiment 1. FIG. 5(a) is a time history waveform of the sound of compressor 11a, FIG. 5(b) is a time history waveform of the sound of compressor 11b, and FIG. 5(c) is a time history waveform of the sound at a reference position P of the heat source unit 1. In FIG. 5, the sound of compressor 11a is indicated by a dashed line, the sound of compressor 11b is indicated by a dashed line, and the sound of heat source unit 1 is indicated by a thick line.

[0041] As described above, in this embodiment, the sound reduction processing unit 52 applies a time lag τ to the control signal of the compressor 11a, thereby shifting the phase of the sound of the compressor 11a from the phase of the sound of the compressor 11b. Then, as shown in Fig. 5(c), the sound of the compressor 11a and the sound of the compressor 11b cancel each other out when added together, thereby reducing the operating sound of the heat source unit 1.

[0042] As described above, in the refrigeration cycle apparatus 100 of this embodiment, the sound reduction processing unit 52 applies a time delay τ to the control signal of the compressor 11a, so that the sounds of the compressors 11a and 11b are in opposite phase and cancel each other out. This makes it possible to achieve low noise without increasing costs by adding additional components such as sound-absorbing materials or speakers to the refrigeration cycle apparatus 100. Furthermore, while the installation location of each drive source is often limited due to the product structure, the control provides a delay in the operation time of each drive source, so that the operating noise can be reduced regardless of the installation location. Furthermore, in the refrigeration cycle apparatus 100 of this embodiment, it is not necessary to lower the operating frequency (rotation speed) of the drive source to reduce operating noise, and there is no need to restrict the operation of the drive source.

[0043] In the above embodiment, an example has been described in which the sound at the reference position P of the heat source unit 1 is reduced, but it is possible to reduce the sound at any position. In this case, the sound reduction processing unit 52 sets the distances δa and δb from the reference position P to the compressors 11a and 11b, and calculates the time lag τ using equation (1).

[0044] Furthermore, in the above embodiment, the compressors 11a and 11b are described as the same type of drive source. However, the noise of the outdoor fans 16a and 16b or the indoor fans 23a and 23b can also be reduced in a similar manner. In this case, the noise reduction processor 52 determines the time lag τ by applying equation (1) to the distances δa and δb from the reference position P to the outdoor fans 16a and 16b, or the distance from the reference position P to the indoor fans 23a and 23b, and the peak frequency of the noise of the outdoor fans 16a and 16b or the peak frequency of the noise of the indoor fans 23a and 23b. The determined time lag τ can then be applied to the control signal for the outdoor fan 16a or the control signal for the indoor fan 23a. This allows the operating noise of the heat source unit 1 or the indoor units 2a and 2b to be reduced.

[0045] Embodiment 2 A second embodiment will be described. The refrigeration cycle apparatus 100 of this embodiment differs from the first embodiment in the processing of the sound reduction processing unit 52. The configuration of the refrigeration cycle apparatus 100 is the same as that of the first embodiment.

[0046] The sound reduction processing unit 52 of this embodiment uses the ambient temperature of the drive source to correct deviations in the sound speed of the air caused by temperature changes in the heat source unit 1. Specifically, the sound reduction processing unit 52 calculates the sound speed v in equation (1) from the following equation (2). v=331.5+0.61×T (2) Here, T is the temperature (° C.) around the driving source, for example, the outside air temperature measured by the outside air temperature sensor 31 or the room temperature measured by the room temperature sensors 32a and 32b.

[0047] The speed of sound changes depending on the air temperature, which in turn changes the traveling speed of sound waves generated from the driving source. Therefore, in an environment where the ambient temperature changes significantly, the ambient temperature must be taken into consideration in order to cancel out the sounds from multiple driving sources. In particular, the refrigeration cycle device 100 may operate all day, and the ambient temperature at the start of operation may differ from the ambient temperature after operation has started, which increases the impact of the ambient temperature. For example, the ambient temperature at the start of operation of the refrigeration cycle device 100 may be 10°C, and six hours after operation, the ambient temperature may be 30°C.

[0048] Therefore, the sound reduction processing unit 52 of this embodiment calculates the sound speed v and the time lag τ at preset time intervals (for example, one hour) even after the refrigeration cycle apparatus 100 starts operating, and provides them to a control signal for one of the multiple drive sources. Since the refrigeration cycle apparatus 100 is usually equipped with temperature sensors that measure the ambient temperature of the drive sources for air conditioning control, the temperatures measured by these temperature sensors can be used to correct the sound speed.

[0049] As described above, in this embodiment as well, noise reduction can be achieved without increasing costs due to the provision of additional components in the refrigeration cycle apparatus 100. Furthermore, by correcting the speed of sound according to the ambient temperature, noise reduction can be achieved even in situations where the ambient temperature of the drive source changes significantly.

[0050] Embodiment 3 A third embodiment will be described. The refrigeration cycle apparatus 100 of this embodiment differs from the first embodiment in the processing of the sound reduction processing unit 52. The rest of the configuration of the refrigeration cycle apparatus 100 is the same as that of the first embodiment.

[0051] In the first embodiment, a case where noise emitted from a drive source such as compressors 11a and 11b is reduced has been described, but vibrations from the drive source are also transmitted to components arranged around the drive source, generating noise due to the vibrations. The refrigeration cycle device 100 of this embodiment aims to reduce noise from components (hereinafter referred to as "peripheral components") that are arranged around the drive source and generate noise when vibrations from the drive source are transmitted to them.

[0052] The peripheral parts are support parts made of metal plate or the like to which the drive source is attached, or piping around the drive source. Fig. 6 is a diagram illustrating the arrangement of peripheral parts in the heat source unit 1 according to embodiment 3. In the example of Fig. 6, support part 161a to which motor 160a of outdoor fan 16a is attached, and support part 161b to which motor 160b of outdoor fan 16b is attached are shown as examples of peripheral parts.

[0053] In the present embodiment, sound reduction processing unit 52 calculates time lag τ based on the same formula (1) as in embodiment 1. However, as shown in Fig. 6, distance δa in formula (1) is the distance (m) from reference position P to support part 161a, and distance δb is the distance (m) from reference position P to support part 161b. v is the sound speed (m / s) of the ambient gas, and f is the frequency (Hz) of the peak sound of support part 161a and support part 161b.

[0054] Distances δa and δb from the reference position P to the support parts 161a and 161b are the distances from the reference position P to the positions where the support parts 161a and 161b vibrate most. The positions where the support parts 161a and 161b vibrate most and the frequencies of the peak sounds of the support parts 161a and 161b are measured during a noise evaluation test before the refrigeration cycle apparatus 100 is shipped, and are stored in the memory unit 53 together with the distances δa and δb from the reference position P to the support parts 161a and 161b.

[0055] The sound reduction processing unit 52 imparts a time lag τ to the control signal for the outdoor fan 16a generated by the operation control unit 51. This causes a time lag τ between the control signal for the outdoor fan 16a and the control signal for the outdoor fan 16b, causing a difference in operation timing between the outdoor fan 16a and the outdoor fan 16b. As a result, the phase of the sound from the support part 161a and the phase of the sound from the support part 161b are shifted and, when added together, cancel each other out, thereby reducing the operating noise of the heat source unit 1.

[0056] As described above, in the refrigeration cycle apparatus 100 of this embodiment, the sound of the surrounding parts vibrated by the drive source is offset in phase by applying a time lag τ to the control signal of the drive source by the sound reduction processing unit 52. This makes it possible to reduce the noise caused by the operation of the drive source in the apparatus (the sound of the drive source and the sound of the surrounding parts) without increasing costs by providing additional parts such as sound absorbing materials or speakers in the refrigeration cycle apparatus 100.

[0057] The driving source or surrounding components that are noise sources vary depending on the operating conditions of the refrigeration cycle apparatus 100. For example, depending on the rotation speed of the outdoor fans 16a and 16b, the noise of the outdoor fans 16a and 16b may increase, or the noise of the support components 161a and 161b may increase. The driving source that is the noise source for each operating condition can be known in advance, for example, during a noise evaluation test of the refrigeration cycle apparatus 100. For this reason, the relationship between the operating conditions of the refrigeration cycle apparatus 100 and the driving source that is the noise source may be stored in the storage unit 53, and the sound reduction processing unit 52 may determine the driving source to be subjected to sound reduction processing based on the current operating condition, and calculate the time delay τ.

[0058] Embodiment 4 A fourth embodiment will be described. The refrigeration cycle apparatus 100 of this embodiment differs from the first embodiment in the arrangement of the driving source. The rest of the configuration of the refrigeration cycle apparatus 100 is the same as that of the first embodiment.

[0059] Fig. 7 is a diagram illustrating the arrangement of the driving sources in the heat source unit 1 according to embodiment 4. As shown in Fig. 7, in the refrigeration cycle apparatus 100 of this embodiment, compressors 11a and 11b, which are the driving sources, are arranged side by side in the vertical direction at the center position inside the housing of the heat source unit 1. As a result, when the time lag τ is calculated using the distances δa and δb from a reference position P provided on the front side to the driving sources, it is possible to reduce the operating noise at the reference positions P on the rear, left, and right sides, which are the same distance from the driving source as the distances δa and δb.

[0060] As described above, in this embodiment as well, noise reduction can be achieved without increasing costs due to the provision of additional components in the refrigeration cycle apparatus 100. Furthermore, in the above-described first to third embodiments, it is possible to reduce the operating noise at the reference position P in one direction, but by arranging the drive source as in this embodiment, it is possible to reduce the operating noise in multiple directions.

[0061] The above is a description of the embodiment; however, the present disclosure is not limited to the above embodiment and can be modified in various ways without departing from the spirit and scope of the present disclosure. Furthermore, the present disclosure includes all possible combinations of the configurations described in the above embodiment. For example, while the above embodiment describes a case in which the refrigeration cycle apparatus 100 is a heat pump chiller, the refrigeration cycle apparatus 100 may also be a refrigerator for cooling warehouses or a direct expansion air conditioner. Furthermore, the above embodiment describes a case in which noise reduction in the refrigeration cycle apparatus 100 is attempted, but the noise reduction process of the present disclosure is not limited to the refrigeration cycle apparatus 100 and can be applied to equipment equipped with multiple drive sources of the same type.

[0062] Furthermore, in the above embodiment, an example has been described in which there are two drive sources, but the number of drive sources may be three or more. Even if there is an odd number of drive sources, by providing a time lag τ to the control signal of at least one of the drive sources and canceling out the noise of the even number of drive sources (for example, in the case of three drive sources, the noise of two drive sources is canceled out), it is possible to achieve lower noise levels than in conventional techniques.

[0063] Various aspects of the present disclosure are summarized below as appendices. (Appendix 1) A refrigeration cycle device comprising a heat source unit, an indoor unit, and a control device, The heat source unit or the indoor unit has a plurality of drive sources that generate sounds with similar frequency characteristics, The control device an operation control unit that outputs control signals for controlling the plurality of drive sources; a sound reduction processing unit that applies a time delay to the control signal of at least one of the plurality of drive sources so that sounds caused by driving the plurality of drive sources are canceled out. (Appendix 2) The refrigeration cycle device described in Appendix 1, wherein the sound reduction processing unit calculates the time difference based on the distance from a reference position to the plurality of driving sources, the speed of sound in the ambient gas, and the frequency of the sound emitted by the plurality of driving sources. (Appendix 3) further comprising a temperature sensor for measuring temperatures around the plurality of driving sources; 3. The refrigeration cycle apparatus according to claim 2, wherein the sound reduction processing unit calculates the sound speed using the temperature measured by the temperature sensor. (Appendix 4) 4. The refrigeration cycle apparatus according to claim 3, wherein the sound reduction processing unit calculates the sound velocity and the time lag at preset time intervals and provides the calculated time lag to the control signal. (Appendix 5) The driving device further includes a plurality of peripheral components that vibrate when the vibrations of the plurality of driving sources are transmitted thereto, The refrigeration cycle device according to any one of appendices 1 to 4, wherein the sound reduction processing unit calculates the time shift based on the distance from a reference position to the plurality of surrounding components, the speed of sound in the surrounding gas, and the frequency of the sound emitted by the plurality of surrounding components. (Appendix 6) The refrigeration cycle apparatus according to claim 5, wherein the driving source is a compressor or an outdoor fan provided in the heat source unit, or an indoor fan provided in the indoor unit, and the peripheral parts are support parts for the compressor, the outdoor fan, or the indoor fan, or piping. (Appendix 7) 7. The refrigeration cycle apparatus according to any one of claims 1 to 6, wherein the plurality of drive sources are arranged vertically side by side at a central position of the heat source unit or the indoor unit. [Explanation of symbols]

[0064] 1 heat source unit, 2a, 2b indoor unit, 5 control device, 10a, 10b refrigerant circuit, 11a, 11b compressor, 12a, 12b four-way valve, 13a, 13b outdoor heat exchanger, 14a, 14b outdoor expansion valve, 15a, 15b accumulator, 16a, 16b outdoor fan, 20 heat medium circuit, 21a, 21b indoor heat exchanger, 22a, 22b flow control valve, 23a, 23b indoor fan, 31 outdoor air temperature sensor, 32a, 32b indoor temperature sensor, 51 operation control unit, 52 sound reduction processing unit, 53 memory unit, 60 water heat exchanger, 80 pump, 100 refrigeration cycle device, 160a, 160b motor, 161a, 161b support parts.

Claims

1. A refrigeration cycle device comprising a heat source unit, an indoor unit, and a control device, The heat source unit or the indoor unit has a plurality of drive sources that generate sounds with similar frequency characteristics, The control device an operation control unit that outputs control signals for controlling the plurality of drive sources; a sound reduction processing unit that applies a time delay to the control signal of at least one of the plurality of drive sources so that sounds caused by driving the plurality of drive sources are canceled out.

2. 2. The refrigeration cycle apparatus according to claim 1, wherein the sound reduction processing unit calculates the time difference based on distances from a reference position to the plurality of driving sources, the speed of sound in the ambient gas, and frequencies of sounds emitted by the plurality of driving sources.

3. further comprising a temperature sensor for measuring temperatures around the plurality of driving sources; The refrigeration cycle apparatus according to claim 2 , wherein the sound reduction processing unit calculates the sound velocity using the temperature measured by the temperature sensor.

4. The refrigeration cycle apparatus according to claim 3 , wherein the sound reduction processing unit obtains the sound velocity and the time lag at preset time intervals, and provides the obtained time lag to the control signal.

5. The driving device further includes a plurality of peripheral components that vibrate when the vibrations of the plurality of driving sources are transmitted thereto, 2. The refrigeration cycle apparatus according to claim 1, wherein the sound reduction processing unit calculates the time difference based on distances from a reference position to the plurality of surrounding components, the speed of sound in the surrounding gas, and frequencies of sounds emitted by the plurality of surrounding components.

6. 6. The refrigeration cycle apparatus according to claim 5, wherein the driving source is a compressor or an outdoor fan provided in the heat source unit, or an indoor fan provided in the indoor unit, and the peripheral parts are support parts of the compressor, the outdoor fan, or the indoor fan, or piping.

7. The refrigeration cycle device according to any one of claims 1 to 6, wherein the plurality of drive sources are arranged vertically side by side at a central position of the heat source unit or the indoor unit.

8. A control device that controls a plurality of drive sources that generate sounds with similar frequency characteristics, an operation control unit that outputs control signals for controlling the plurality of drive sources; a sound reduction processing unit that applies a time delay to the control signal of at least one of the plurality of drive sources so that sounds resulting from the driving of the plurality of drive sources are canceled out.

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