EP-4741721-A1 - HEAT SOURCE UNIT OF REFRIGERATION CYCLE DEVICE, AND REFRIGERATION CYCLE DEVICE

EP4741721A1EP 4741721 A1EP4741721 A1EP 4741721A1EP-4741721-A1

Abstract

A heat source unit (2) includes an electric component unit (70), a heat source-side refrigerant main flow path (300), and a first refrigerant sub flow path (46) including a first cooling portion (47) that cools a first portion of the electric component unit (70) and a second portion of the electric component unit (70). The heat source-side refrigerant main flow path (300) includes an accumulator (29), a compressor (21), a heat source-side heat exchanger (23), and a heat source-side expansion valve (25). The heat source-side refrigerant main flow path (300) is connected to a utilization-side refrigerant flow path (500) of a utilization unit (3a, 3b) to form a refrigerant circuit (10). The first refrigerant sub flow path (46) branches from a liquid flow path (340) extending from the heat source-side heat exchanger (23) to the utilization-side refrigerant flow path (500) in the heat source-side refrigerant main flow path (300), and causes a refrigerant to flow in a gas flow path (310) between the accumulator (29) and the compressor (21) in the heat source-side refrigerant main flow path (300).

Inventors

NAKANISHI, Takaya
FUKUYAMA, Yuta
YAMADA, YUJI
YASUNO, Masafumi
YAMAMOTO, KOHEI

Assignees

DAIKIN INDUSTRIES, LTD.

Dates

Publication Date: 20260513
Application Date: 20250624

Claims (12)

A heat source unit (2) of a refrigeration cycle apparatus, the heat source unit comprising: an electric component unit (70); a heat source-side refrigerant main flow path (300) that includes an accumulator (29), a compressor (21), a heat source-side heat exchanger (23), and a heat source-side main expansion mechanism (25), and is connected to a utilization-side refrigerant flow path (500) of a utilization unit (3a, 3b) to form a refrigerant circuit (10); and a first refrigerant sub flow path (46) including a first cooling portion (47) that cools a first portion of the electric component unit and a second portion of the electric component unit, wherein the first refrigerant sub flow path branches from a liquid flow path (340) extending from the heat source-side heat exchanger to the utilization-side refrigerant flow path in the heat source-side refrigerant main flow path, and causes a refrigerant to flow in a gas flow path (310) between the accumulator and the compressor in the heat source-side refrigerant main flow path.
The heat source unit of the refrigeration cycle apparatus according to claim 1, the heat source unit further comprising: a first flow rate adjustment mechanism (48) that adjusts a flow rate of the refrigerant flowing through the first refrigerant sub flow path; and a control unit (7), wherein the control unit controls an opening degree of the first flow rate adjustment mechanism on a basis of a discharge pipe temperature (Td) of the compressor.
The heat source unit of the refrigeration cycle apparatus according to claim 2, wherein the control unit controls the opening degree of the first flow rate adjustment mechanism on a basis of the discharge pipe temperature of the compressor and a temperature of the electric component unit.
The heat source unit of the refrigeration cycle apparatus according to any one of claims 1 to 3, wherein a housing space of the electric component unit is sealed by a housing (70a), and the first refrigerant sub flow path cools the housing space inside the housing.
The heat source unit of the refrigeration cycle apparatus according to any one of claims 2 to 4, the heat source unit further comprising: a second refrigerant sub flow path (66) including a second cooling portion (67) that cools a second portion of the electric component unit, and a second flow rate adjustment mechanism (68) that adjusts an amount of the refrigerant flowing through the second cooling portion, wherein the second refrigerant sub flow path connects a liquid pipe (34a) closer to the heat source-side heat exchanger with respect to the heat source-side main expansion mechanism and a liquid pipe (34b) opposite to the heat source-side heat exchanger with respect to the heat source-side main expansion mechanism, the first refrigerant sub flow path branches from a position closer to the utilization-side refrigerant circuit than a position opposite to the heat source-side heat exchanger with respect to the heat source-side main expansion mechanism to which the second refrigerant sub flow path is connected in the liquid flow path extending from the heat source-side heat exchanger to the utilization-side refrigerant flow path in the heat source-side refrigerant main flow path.
The heat source unit of the refrigeration cycle apparatus according to claim 5, the heat source unit further comprising a fourth refrigerant sub flow path (61) including a fourth cooling portion (62) that cools the first portion of the electric component unit, and a fourth flow rate adjustment mechanism (63) that expands the refrigerant flowing through the fourth cooling portion, wherein the fourth refrigerant sub flow path branches from the liquid flow path extending from the heat source-side heat exchanger to the utilization-side refrigerant flow path in the heat source-side refrigerant main flow path, and causes the refrigerant to flow to a gas flow path on a suction side of the compressor in the heat source-side refrigerant main flow path.
The heat source unit of the refrigeration cycle apparatus according to claim 6, wherein the heat source-side refrigerant main flow path further includes a subcooling heat exchanger (45) disposed in the liquid flow path extending from the heat source-side heat exchanger to the utilization-side refrigerant flow path, the heat source unit further includes a third refrigerant sub flow path (41) branching from the liquid flow path, and the third refrigerant sub flow path includes a third flow rate adjustment mechanism (44) that expands the refrigerant flowing inside, causes the subcooling heat exchanger to exchange heat between the refrigerant having passed through the third flow rate adjustment mechanism and the refrigerant flowing through the liquid flow path of the heat source-side refrigerant main flow path, and causes the refrigerant after heat exchange to flow into the gas flow path on the suction side of the compressor in the heat source-side refrigerant main flow path.
The heat source unit of the refrigeration cycle apparatus according to claim 6 or 7, wherein the control unit controls an opening degree of the second flow rate adjustment mechanism or the fourth flow rate adjustment mechanism on a basis of the temperature of the electric component unit.
The heat source unit of the refrigeration cycle apparatus according to any one of claims 6 to 8, wherein the electric component unit includes a first electric component (81a) and a second electric component (82a), the fourth refrigerant sub flow path cools the first electric component.
The heat source unit of the refrigeration cycle apparatus according to claim 9, wherein a calorific value of the first electric component is larger than a calorific value of the second electric component.
The heat source unit of the refrigeration cycle apparatus according to any one of claims 6 to 10, wherein the fourth refrigerant sub flow path branches from a position closer to the utilization-side refrigerant flow path than a position opposite to the heat source-side heat exchanger with respect to the heat source-side main expansion mechanism to which the second refrigerant sub flow path is connected in the liquid flow path extending from the heat source-side heat exchanger to the utilization-side refrigerant flow path in the heat source-side refrigerant main flow path.
A refrigeration cycle apparatus (1) comprising: the heat source unit (2) according to any one of claims 1 to 11; and one or more of the utilization units (3a, 3b) connected to the heat source unit.

Description

TECHNICAL FIELD The present disclosure relates to a heat source unit of a refrigeration cycle apparatus and the refrigeration cycle apparatus. BACKGROUND ART Conventionally, there is a cooling circuit for cooling an electric component unit having one end connected to a liquid pipe and the other end connected to an upstream side of an accumulator (Patent Literature 1 (JP 2022-146443 A)). SUMMARY OF THE INVENTION <Technical Problem> In the conventional cooling circuit, in order to suppress an increase in a discharge temperature of a compressor due to an R32 refrigerant, it is necessary to provide a liquid injection circuit, which may complicate the circuit, and there is a problem that the cooling capacity may be insufficient when the calorific value of the electric component unit increases. <Solution to Problem> A heat source unit of a refrigeration cycle apparatus according to a first aspect includes an electric component unit, a heat source-side refrigerant main flow path, and a first refrigerant sub flow path. The heat source-side refrigerant main flow path includes an accumulator, a compressor, a heat source-side heat exchanger, and a heat source-side main expansion mechanism. The heat source-side refrigerant main flow path is connected to a utilization-side refrigerant flow path of a utilization unit to form a refrigerant circuit. The first refrigerant sub flow path includes a first cooling portion that cools a first portion of an electric component unit and a second portion of the electric component unit. The first refrigerant sub flow path branches from a liquid flow path extending from the heat source-side heat exchanger to the utilization-side refrigerant flow path in the heat source-side refrigerant main flow path, and causes a refrigerant to flow in a gas flow path between the accumulator and the compressor in the heat source-side refrigerant main flow path. In the heat source unit of the refrigeration cycle apparatus, the first refrigerant sub flow path can be used for cooling the electric component unit, and can also cool a gas refrigerant sucked into the compressor. A heat source unit of a refrigeration cycle apparatus according to a second aspect is the heat source unit according to the first aspect, and includes a first flow rate adjustment mechanism and a control unit. The first flow rate adjustment mechanism adjusts a flow rate of the refrigerant flowing through the first refrigerant sub flow path. The control unit controls an opening degree of the first flow rate adjustment mechanism on the basis of a discharge pipe temperature of the compressor. In the heat source unit of the refrigeration cycle apparatus, the opening degree of the first flow rate adjustment mechanism is increased to cool the gas refrigerant sucked into the compressor when the discharge pipe temperature of the compressor rises, so that the discharge pipe temperature of the compressor can be lowered to protect the compressor. A heat source unit of a refrigeration cycle apparatus according to a third aspect is the heat source unit according to the second aspect, in which the control unit controls the opening degree of the first flow rate adjustment mechanism on the basis of the discharge pipe temperature of the compressor and a temperature of the electric component unit. In the heat source unit of the refrigeration cycle apparatus, the opening degree of the first flow rate adjustment mechanism is increased when the discharge pipe temperature of the compressor rises and when the temperature of the electric component unit rises, so that the gas refrigerant sucked into the compressor can be cooled to lower the discharge pipe temperature of the compressor, and the electric component unit can be cooled. A heat source unit of a refrigeration cycle apparatus according to a fourth aspect is the heat source unit according to any one of the first to third aspects, in which a housing space of the electric component unit is sealed by a housing. The first refrigerant sub flow path cools the housing space inside the housing. In the heat source unit of the refrigeration cycle apparatus, the discharge pipe temperature of the compressor can be lowered, and the housing space for housing the electric component can be cooled with a smaller cooling amount than in a case of cooling the electric component. A heat source unit of a refrigeration cycle apparatus according to a fifth aspect is the heat source unit according to any one of the second to fourth aspects, and further includes a second refrigerant sub flow path. The second refrigerant sub flow path includes a second cooling portion and a second flow rate adjustment mechanism. The second cooling portion cools the second portion of the electric component unit. The second flow rate adjustment mechanism adjusts an amount of the refrigerant flowing through the second cooling portion. The second refrigerant sub flow path connects the liquid pipe closer to the heat source-side heat exchanger with