CN117804089A - Heat pump system and control method thereof - Google Patents

Abstract

The invention belongs to the field of air conditioners, and particularly provides a heat pump system and a control method thereof, which aim to solve the problems that the refrigerating and heating capacities of the existing heat pump system are not balanced and the liquid separation of a two-phase refrigerant after heat exchange is difficult. The valve group included in the heat pump system provided by the invention comprises: the first throttling component is arranged on the first pipeline, and the first pipeline is connected with the gas-liquid separator and the indoor heat exchanger; and the second throttling component is arranged on a second pipeline, and the second pipeline is connected with the gas-liquid separator and the outdoor heat exchanger. When the heat pump system is used for refrigerating, the first throttling part is adjusted to realize liquid separation of the refrigerant in a proper throttling state, so that the problem that the refrigeration is biased to influence the heating effect is avoided, and the refrigerating and heating capacities are improved to a certain extent; when the heat pump system is used for heating, the outlet pressure of the refrigerant is regulated before the refrigerant enters the liquid separation by regulating the second throttling part, so that the problem of difficult liquid separation is avoided.

Description

Heat pump system and control method thereof

Technical Field

The invention relates to an air conditioner, in particular to a heat pump system and a control method thereof.

Background

The heat pump system has better energy-saving effect as the heat pump system can realize refrigeration and heating, and is used as a preferable energy conversion system of an air conditioner and the like.

In the heat exchange of the existing heat pump system, the heat exchanger is not used as a condenser or an evaporator, so that the designed heat pump system has partial refrigeration or partial heating, and the good effects of refrigeration and heating cannot be achieved; for the external heat exchanger with the top air outlet, due to uneven wind fields, when the external heat exchanger meets the requirement of condensation capacity, the evaporation capacity also has larger lifting space; when the refrigerant in the heat exchanger is subjected to evaporation heat exchange, the state of the refrigerant comprises a gaseous state and a liquid state, the refrigerant in the two-phase state exchanges heat in the heat pump system, and the liquid separation is difficult due to the difference of gravity and back pressure of each branch port of the heat exchange of the two-phase refrigerant.

Disclosure of Invention

The heat pump system aims to solve the problems in the prior art, namely the problems that the refrigerating and heating capacities of the existing heat pump system are not balanced and the two-phase refrigerant after heat exchange is difficult to separate. The present invention provides a heat pump system comprising: comprising the following steps: the compressor, the first four-way valve, the indoor heat exchanger and the outdoor heat exchanger are sequentially arranged on the main loop; the outdoor heat exchanger is connected with the compressor through the first four-way valve;

wherein, the device also comprises a gas-liquid separator and a valve group;

the valve group includes:

the first throttling component is arranged on a first pipeline, a first end of the first pipeline is connected with the gas-liquid separator, and a second end of the first pipeline is connected with the indoor heat exchanger;

the second throttling component is arranged on a second pipeline, the first end of the second pipeline is connected with the gas-liquid separator, and the second end of the second pipeline is connected with the outdoor heat exchanger;

the second four-way valve is connected to the first pipeline and the second pipeline, and is close to the first end of the first pipeline and close to the second end of the second pipeline section.

Under the condition of adopting the technical scheme, when the heat pump system is used for refrigerating, the refrigerant is discharged from the exhaust port of the compressor, enters the outdoor heat exchanger through the first four-way valve, enters the first pipeline through the second four-way valve, throttles through the first throttling component on the first pipeline, enters the gas-liquid separator through the two-phase refrigerant, enters the indoor heat exchanger through the second throttling component on the second pipeline in the full-open state, and returns to the air suction port of the compressor through the first four-way valve to complete the refrigerating cycle; in the heating process, the refrigerant is discharged from the exhaust port of the compressor, enters the indoor heat exchanger through the first four-way valve, throttles through the second throttling component on the second pipeline, enters the gas-liquid separator through the second pipeline by the two-phase refrigerant through the second four-way valve, enters the outdoor heat exchanger through the first throttling component on the first pipeline in the full-open state by the liquid-phase refrigerant, and finally returns to the air suction port of the compressor through the first four-way valve to complete the whole heating cycle. Therefore, in the refrigerating process, the opening degree of the first throttling part is regulated, the proper throttling state of the refrigerant before liquid separation is regulated, and the single-phase liquid refrigerant after liquid separation is subjected to heat exchange, so that the refrigerating and heating uniformity of the heat pump system is improved, and the refrigerating and heating capacities of the whole heat pump system are guaranteed to have better service performance; in the heating process, the opening degree of the second throttling part is adjusted to adjust the outlet pressure of the refrigerant before liquid separation, so that the problem of difficult liquid separation of the refrigerant is avoided. Wherein the throttle member is in a fully open state may be in a state of no function.

In a specific embodiment of the foregoing heat pump system, the valve set further includes a first valve disposed in a third pipeline, the third pipeline is connected in parallel to the first pipeline, and the first end and the second end of the third pipeline are both connected near the first throttling part.

In a specific embodiment of the heat pump system, the valve set further includes a second valve disposed in parallel with a fourth pipeline, where the fourth pipeline is connected to the second pipeline in parallel, and the first end and the second end of the fourth pipeline are both close to the second throttling component.

In a specific embodiment of the above heat pump system, the valve set further includes a third valve disposed in a fifth pipeline, a first end of the fifth pipeline is connected to the gas-liquid separator, and a second end of the fifth pipeline is connected to the compressor.

In a specific embodiment of the above heat pump system, the valve group further includes: and the third throttling component is arranged on the fifth pipeline and is arranged between the gas-liquid separator and the third valve.

In a specific embodiment of the heat pump system, the first valve is a check valve, and is configured to allow only the liquid-phase refrigerant to flow from the gas-liquid separator to the indoor heat exchanger.

In a specific embodiment of the heat pump system, the second valve is a check valve, and is configured to allow only the liquid-phase refrigerant to flow from the gas-liquid separator to the outdoor heat exchanger.

In a specific embodiment of the heat pump system, the third valve is a check valve configured to allow only the gas-phase refrigerant to flow from the gas-liquid separator to the compressor.

Under the condition of adopting the technical scheme, when the heat pump system is used for refrigerating, the refrigerant is discharged from the exhaust port of the compressor, enters the outdoor heat exchanger through the first four-way valve, enters the first pipeline through the second four-way valve, throttles through the first throttling component on the first pipeline, enters the gas-liquid separator in a two-phase state, and enters the third valve and the third throttling component of the fifth pipeline through the separated gas-phase refrigerant until entering the compressor; after passing through the second four-way valve, the separated liquid refrigerant passes through a second throttling component in a full-open state on a second pipeline, passes through a second valve on a fourth pipeline, finally enters into an indoor heat exchanger, and returns to an air suction port of a compressor through the first four-way valve, so that refrigeration cycle is completed; in the heating process, the refrigerant is discharged from the exhaust port of the compressor, enters the indoor heat exchanger through the first four-way valve, is throttled through the second throttling component on the second pipeline, enters the gas-liquid separator through the second pipeline through the second four-way valve, and enters the third valve and the third throttling component of the fifth pipeline through the separated gas-phase refrigerant until entering the compressor; the separated liquid refrigerant passes through a first throttling part in a fully-opened state on a first pipeline, passes through a first valve on a third pipeline, enters an outdoor heat exchanger through a second four-way valve, and finally returns to an air suction port of a compressor through the first four-way valve to complete the whole heating cycle. Therefore, in the refrigerating process, the opening degree of the first throttling part is regulated, the proper throttling state of the refrigerant before liquid separation is regulated, the single-phase liquid refrigerant is subjected to heat exchange after liquid separation, the refrigerating and heating uniformity of the heat pump system is improved, the refrigerating and heating capacities of the whole heat pump system are guaranteed to have better service performance, and the valve diameter of the throttling part is smaller, the fourth pipeline connected with the second pipeline in parallel is additionally arranged, so that the liquid refrigerant can pass through the second throttling part and the second valve at the same time, the cross section area of the refrigerant flowing through is increased, and the throttling loss is avoided; in the heating process, the opening degree of the second throttling part is adjusted, the outlet pressure of the refrigerant before liquid separation is adjusted, the problem that liquid separation of the refrigerant is difficult is avoided, and the valve diameter of the throttling part is smaller, a third pipeline connected with the first pipeline in parallel is additionally arranged, the liquid refrigerant can pass through the first throttling part and the first valve at the same time, the sectional area of the refrigerant flowing through is increased, and throttling loss is avoided. Wherein the throttle member is in a fully open state may be in a state of no function.

In a specific embodiment of the above heat pump system, the outdoor heat exchanger includes

The outdoor heat exchanger comprises a plurality of heat exchange pieces which are sequentially arranged, two adjacent heat exchange pieces are connected through a sixth pipeline, a first end of a first heat exchange piece is connected with the first four-way valve, and a first end of a bottom heat exchange piece is connected with the indoor heat exchanger;

a fourth valve provided on the sixth pipeline;

a seventh pipe having a first end connected to the heat exchange member except the bottom heat exchange member and a second end connected to the indoor heat exchanger;

a fifth valve provided on the seventh pipe;

an eighth pipeline, the first end of which is connected with the heat exchange piece except the bottom heat exchange piece, and the second end of which is connected with the first four-way valve;

a sixth valve provided on the eighth pipe;

and a fourth throttling part arranged on the eighth pipeline.

Under the condition that the technical scheme is adopted, when the heat pump system is used for refrigerating, a refrigerant is discharged from an exhaust port of a compressor, enters a first heat exchange piece on an outdoor heat exchanger through a first four-way valve, opens a fourth valve, closes a fifth valve and a sixth valve, and can only enter the rest heat exchange piece through a sixth pipeline, passes through a fourth throttling part on an eighth pipeline until entering a bottom heat exchange piece, enters a first pipeline through a second four-way valve, enters a first throttling part on the first pipeline for throttling, enters a gas-liquid separator through a two-phase refrigerant, and enters a third valve and a third throttling part of a fifth pipeline through a separated gas-phase refrigerant until entering the compressor; after passing through the second four-way valve, the separated liquid refrigerant passes through a second throttling component in a full-open state on a second pipeline, passes through a second valve on a fourth pipeline, finally enters into an indoor heat exchanger, and returns to an air suction port of a compressor through the first four-way valve, so that refrigeration cycle is completed; in the heating process, the refrigerant is discharged from the exhaust port of the compressor, enters the indoor heat exchanger through the first four-way valve, throttles through the second throttling component on the second pipeline, enters the gas-liquid separator through the second pipeline through the second four-way valve, and enters the third valve and the throttling component of the fifth pipeline through the separated gas-phase refrigerant until entering the compressor; the separated liquid refrigerant passes through a first throttling part in a fully-opened state on the first pipeline, passes through a first valve on the third pipeline, enters the outdoor heat exchanger through the second four-way valve, closes the fourth valve, opens the fifth valve and the sixth valve, can pass through a heat exchange part of the seventh pipeline and a heat exchange part of the eighth pipeline at the same time, and finally returns to the air suction port of the compressor through the first four-way valve to complete the whole heating cycle. It is worth mentioning that when the heat pump system is used for refrigerating, the fourth valve is opened, the fifth valve and the sixth valve are closed, so that a plurality of heat exchange pieces are connected in series, the supercooling degree of the refrigerant is increased, the two-phase enthalpy difference of the refrigerant is larger, the only effect of the refrigerant is improved, and the overall refrigerating performance is improved; in the heating process by using the heat pump system, the fourth valve is closed, the fifth valve and the sixth valve are opened, so that a plurality of heat exchange pieces are connected in parallel, the pressure of the refrigerant flowing through the bottom heat exchange piece is increased by the throttling adjustment of the fourth throttling part, and the flow is reduced, so that the evaporation temperature of the bottom heat exchange piece is higher than that of the first heat exchange piece, and the bottom heat exchange piece is not easy to frost.

The invention also provides a control method for the heat pump system, which is characterized by comprising the following steps:

under the condition that the heat pump system is in a refrigeration mode, the opening degree of the first throttling component can be adjusted, and the second throttling component is fully opened;

the refrigerant subjected to heat exchange by the outdoor heat exchanger enters the gas-liquid separator after being throttled by the first throttling component, and the separated liquid refrigerant is subjected to heat exchange by the indoor heat exchanger through the second throttling component in a fully opened state; and/or

Under the condition that the heat pump system is in a heating mode, the opening degree of the second throttling component can be adjusted, so that the first throttling component is fully opened;

and the refrigerant subjected to heat exchange by the indoor heat exchanger enters the gas-liquid separator after being throttled by the second throttling component, and the separated liquid refrigerant is subjected to heat exchange by the outdoor heat exchanger through the first throttling component in a fully opened state.

The invention also provides a control method for the heat pump system, which is characterized by comprising the following steps:

under the condition that the heat pump system is in a refrigeration mode, the fourth valve is opened, the fifth valve and the sixth valve are closed, and the refrigerant completes heat exchange of the outdoor unit;

the opening degree of the first throttling component is adjustable, and the second throttling component is fully opened;

the refrigerant subjected to heat exchange by the outdoor heat exchanger enters the gas-liquid separator after being throttled by the first throttling component, and the separated liquid refrigerant is subjected to heat exchange by the indoor heat exchanger through the second throttling component in a fully opened state; and/or

Under the condition that the heat pump system is in a heating mode, the opening degree of the second throttling component can be adjusted, so that the first throttling component is fully opened;

and the refrigerant subjected to heat exchange by the outdoor heat exchanger enters the gas-liquid separator after being throttled by the second throttling component, and the liquid refrigerant subjected to separation is subjected to heat exchange by the outdoor heat exchanger through the first throttling component in a fully opened state.

And closing the fourth valve, opening the fifth valve and the six valves, and finishing heat exchange of the outdoor unit by the refrigerant.

As can be appreciated by those skilled in the art, in the technical solution of the present invention, a heat pump system includes: the device comprises a compressor, a first four-way valve, an indoor heat exchanger, an outdoor heat exchanger and a gas-liquid separator; wherein the bag comprises a valve set; the valve group includes: the first throttling component is arranged on a first pipeline, a first end of the first pipeline is connected with the gas-liquid separator, and a second end of the first pipeline is connected with the indoor heat exchanger; the second throttling component is arranged on a second pipeline, the first end of the second pipeline is connected with the gas-liquid separator, and the second end of the second pipeline is connected with the outdoor heat exchanger; the second four-way valve is connected to the first pipeline and the second pipeline, and is close to the first end of the first pipeline and close to the second end of the second pipeline section. The invention improves the problems of unbalanced refrigeration and heating capacity and difficult liquid separation of the two-phase refrigerant after heat exchange in the heat pump system in the prior art into the problems of unbalanced refrigeration and heating capacity and difficult liquid separation of the two-phase refrigerant by respectively throttling through the first throttling part and the second throttling part and then separating liquid in the refrigeration and heating paths.

Drawings

FIG. 1 is a schematic illustration of a heat pump system of the invention;

fig. 2 is a schematic diagram of another inventive heat pump system.

Reference numerals: 1. a compressor; 2. a first four-way valve; 3. an indoor heat exchanger; 4. an outdoor heat exchanger; 5. a gas-liquid separator; 6. a valve group; 61. a first throttle member; 62. a second throttle member; 63. a second four-way valve; 64. a first pipeline; 65. a second pipeline; 66. a first valve; 67. a third pipeline; 68. a second valve; 69. a fourth pipeline; 610. a third valve; 611. a fifth pipeline; 612. a third throttle member; 41. a heat exchange member; 42. a sixth pipeline; 43. a fourth valve; 44. a seventh pipeline; 45. a fifth valve; 46. an eighth pipeline; 47. a sixth valve; 48. and a fourth throttle member.

Detailed Description

Preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are merely for explaining the technical principles of the present invention, and are not intended to limit the scope of the present invention. Those skilled in the art can adapt it as desired to suit a particular application.

It should be noted that, in the description of the present invention, terms such as "upper," "lower," "left," "right," "inner," "outer," and the like indicate directional or positional relationships, and are based on the directional or positional relationships shown in the drawings, which are merely for convenience of description, and do not indicate or imply that the relevant devices or elements must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the invention. Furthermore, the ordinal terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

Furthermore, it should be noted that, in the description of the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the above terms in the present invention can be understood by those skilled in the art according to the specific circumstances.

Referring first to fig. 1-2, fig. 1 is a schematic diagram of a heat pump system of the invention;

fig. 2 is a schematic diagram of another inventive heat pump system. As shown in fig. 1 to 2, the heat pump system of the present invention includes: the heat pump system includes: comprising the following steps: a compressor 1, a first four-way valve 2, an indoor heat exchanger 3, an outdoor heat exchanger 4 and a gas-liquid separator 5; wherein, the valve group 6 is also included; the valve group 6 includes: a first throttle member 61 provided in a first pipe 64, a first end of the first pipe 64 being connected to the gas-liquid separator 5, and a second end of the first pipe 64 being connected to the indoor heat exchanger 3; a second throttle member 62 provided in a second pipe 65, a first end of the second pipe 65 being connected to the gas-liquid separator 5, and a second end of the second pipe 65 being connected to the outdoor heat exchanger 4; and a second four-way valve 63 connected to the first pipe 64 and the second pipe 65, wherein the second four-way valve 63 is disposed near the first end of the first pipe 64 and near the second end of the second pipe section.

Specifically, when the heat pump system is used for refrigerating, the refrigerant is discharged from the exhaust port of the compressor 1, enters the outdoor heat exchanger 4 through the first four-way valve 2, enters the first pipeline 64 through the second four-way valve 63, throttles through the first throttling component 61 on the first pipeline 64, enters the gas-liquid separator 5 in a two-phase state, enters the indoor heat exchanger 3 through the second throttling component 62 on the second pipeline 65 in a fully-opened state, and returns to the air suction port of the compressor 1 through the first four-way valve 2, so that the refrigerating cycle is completed; in the heating process, the refrigerant is discharged from the exhaust port of the compressor 1, enters the indoor heat exchanger 3 through the first four-way valve 2, throttles through the second throttling component 62 on the second pipeline 65, enters the gas-liquid separator 5 through the second pipeline 65 through the second four-way valve 63, enters the outdoor heat exchanger 4 through the first throttling component 61 in the fully opened state on the first pipeline 64 through the second four-way valve 63, and finally returns to the air suction port of the compressor 1 through the first four-way valve 2 to complete the whole heating cycle. Therefore, in the refrigerating process, the opening degree of the first throttling part 61 is adjusted to adjust the proper throttling state of the refrigerant before liquid separation, and the single-phase liquid refrigerant after liquid separation is subjected to heat exchange, so that the refrigerating and heating uniformity of the heat pump system is improved, and the refrigerating and heating capacities of the whole heat pump system are ensured to have better service performance; in the heating process, the opening degree of the second throttling part 62 is adjusted to adjust the outlet pressure of the refrigerant before liquid separation, so that the problem of difficult liquid separation of the refrigerant is avoided. Wherein the throttle member is in a fully open state may be in a state of no function.

With continued reference to fig. 1, the valve assembly 6 further includes a first valve 66 disposed in a third pipeline 67, the third pipeline 67 is connected in parallel with the first pipeline 64, and a first end and a second end of the third pipeline 67 are both connected near the first throttling element 61.

The valve assembly 6 further comprises a second valve 68 arranged in parallel with the fourth conduit 69, the fourth conduit 69 being connected to the second conduit 65, and the first and second ends of the fourth conduit 69 being connected close to the second restriction member 62.

The valve group 6 further comprises a third valve 610, which is disposed in a fifth pipeline 611, wherein a first end of the fifth pipeline 611 is connected to the gas-liquid separator 5, and a second end of the fifth pipeline 611 is connected to the compressor 1.

The valve group 6 further includes: a third throttling part 612 disposed in the fifth pipeline 611 and interposed between the gas-liquid separator 5 and the third valve 610.

The first valve 66 is a one-way valve configured to allow only the liquid-phase refrigerant to flow from the gas-liquid separator 5 to the indoor heat exchanger 3.

The second valve 68 is a check valve configured to allow only the liquid-phase refrigerant to flow from the gas-liquid separator 5 to the outdoor heat exchanger 4.

The third valve 610 is a check valve and is configured to allow only the gas-phase refrigerant to flow from the gas-liquid separator 5 to the compressor 1.

In the case of adopting the above-described technical solution, when the heat pump system is used to perform a refrigeration process, the refrigerant is discharged from the exhaust port of the compressor 1, enters the outdoor heat exchanger 4 through the first four-way valve 2, enters the first pipeline 64 through the second four-way valve 63, throttles through the first throttling member 61 on the first pipeline 64, enters the gas-liquid separator 5 in a two-phase state, and enters the third valve 610 and the third throttling member 612 of the fifth pipeline 611 until entering the compressor 1 in a separated gas-phase state; after passing through the second four-way valve 63, the separated liquid refrigerant passes through the second throttling component 62 which is in a full-open state and is arranged on the second pipeline 65, and simultaneously passes through the second valve 68 on the fourth pipeline 69, and finally enters the indoor heat exchanger 3 to return to the air suction port of the compressor 1 through the first four-way valve 2, so that the refrigeration cycle is completed; during heating, the refrigerant is discharged from the exhaust port of the compressor 1, enters the indoor heat exchanger 3 through the first four-way valve 2, throttles through the second throttling component 62 on the second pipeline 65, enters the gas-liquid separator 5 through the second pipeline 65 through the second four-way valve 63, and enters the third valve 610 and the third throttling component 612 of the fifth pipeline 611 through the separated gas-phase refrigerant until entering the compressor 1; the separated liquid refrigerant passes through the first throttling part 61 which is in a full open state on the first pipeline 64, passes through the first valve 66 on the third pipeline 67, enters the outdoor heat exchanger 4 through the second four-way valve 63, and finally returns to the air suction port of the compressor 1 through the first four-way valve 2 to complete the whole heating cycle. Therefore, in the refrigerating process, by adjusting the opening of the first throttling part 61, adjusting the proper throttling state of the refrigerant before liquid separation, the single-phase liquid refrigerant is subjected to heat exchange after liquid separation, so that the uniformity of refrigerating and heating of the heat pump system is improved, the refrigerating and heating capacities of the whole heat pump system are ensured to have better service performance, and the fourth pipeline 69 connected with the second pipeline 65 in parallel is added due to the small valve diameter of the throttling part, so that the liquid refrigerant can pass through the second throttling part 62 and the second valve 68 at the same time, the cross section area of the refrigerant flowing through is increased, and the throttling loss is avoided; in the heating process, the opening degree of the second throttling part 62 is adjusted, the outlet pressure of the refrigerant before liquid separation is adjusted, the problem that the refrigerant is difficult to separate liquid is avoided, and the valve diameter of the throttling part is smaller, the third pipeline 67 connected with the first pipeline 64 in parallel is added, the liquid refrigerant can pass through the first throttling part 61 and the first valve 66 at the same time, the sectional area of the refrigerant flowing through is increased, and throttling loss is avoided. Wherein the throttle member is in a fully open state may be in a state of no function.

The first throttle member 61 and the second throttle member 62 are preferably electronic expansion valves, and in other embodiments, the first throttle member 61 and the second throttle member 62 may be thermal expansion valves, throttle capillaries, or the like.

The first valve 66, the second valve 68 and the third valve 610 are preferably electronic directional valves, and may be directional valves.

In the specific embodiment of the heat pump system, the outdoor heat exchanger 4 includes a plurality of heat exchanging elements 41 sequentially arranged, two adjacent heat exchanging elements 41 are connected through a sixth pipeline 42, a first end of the top heat exchanging element 41 is connected with the first four-way valve 2, and a first end of the bottom heat exchanging element 41 is connected with the indoor heat exchanger 3; a fourth valve 43 disposed on the sixth pipeline 42; a seventh pipe 44 having a first end connected to the heat exchanging member 41 except the bottom heat exchanging member 41 and a second end connected to the indoor heat exchanger 3; a fifth valve 45 provided on the seventh pipe 44; an eighth pipe 46 having a first end connected to the heat exchanging member 41 except the bottom heat exchanging member 41 and a second end connected to the first four-way valve 2; a sixth valve 47 provided on the eighth pipe 46; a fourth throttle member 48 provided on the eighth pipe 46.

Specifically, when the heat pump system is used for a refrigerating process, a refrigerant is discharged from the exhaust port of the compressor 1, enters the top heat exchange piece 41 on the outdoor heat exchanger 4 through the first four-way valve 2, opens the fourth valve 43, closes the fifth valve 45 and the sixth valve 47, and can only enter the rest heat exchange piece 41 through the sixth pipeline 42, passes through the fourth throttling part 48 on the eighth pipeline 46 until entering the bottom heat exchange piece 41, enters the first pipeline 64 through the second four-way valve 63, throttles through the first throttling part 61 on the first pipeline 64, enters the gas-liquid separator 5 through the two-phase refrigerant, and enters the third valve 610 and the third throttling part 612 of the fifth pipeline 611 through the separated gas-phase refrigerant until entering the compressor 1; after passing through the second four-way valve 63, the separated liquid refrigerant passes through the second throttling component 62 which is in a full-open state and is arranged on the second pipeline 65, and simultaneously passes through the second valve 68 on the fourth pipeline 69, and finally enters the indoor heat exchanger 3 to return to the air suction port of the compressor 1 through the first four-way valve 2, so that the refrigeration cycle is completed; the refrigerant flows to the indoor heat exchanger 3 after sequentially exchanging heat through the heat exchanging pieces 41, and after sequentially exchanging heat through the heat exchanging pieces 41, the supercooling degree of the refrigerant can be increased, so that the two-phase enthalpy difference of the refrigerant is large, the refrigerating effect of the indoor heat exchanger 3 can be improved, and the integral refrigerating performance of the heat pump system is improved.

During heating, the refrigerant is discharged from the exhaust port of the compressor 1, enters the indoor heat exchanger 3 through the first four-way valve 2, throttles through the second throttling component 62 on the second pipeline 65, enters the gas-liquid separator 5 through the second pipeline 65 through the second four-way valve 63, and enters the third valve 610 and the throttling component of the fifth pipeline 611 through the separated gas-phase refrigerant until entering the compressor 1; the separated liquid refrigerant passes through the first throttling part 61 in a fully opened state on the first pipeline 64, passes through the first valve 66 on the third pipeline 67, enters the outdoor heat exchanger 4 through the second four-way valve 63, closes the fourth valve 43, opens the fifth valve 45 and the sixth valve 47, can pass through the heat exchange part 41 of the seventh pipeline 44 and the heat exchange part 41 of the eighth pipeline 46 at the same time, and finally returns to the air suction port of the compressor 1 through the first four-way valve 2 to complete the whole heating cycle. Because the refrigerant flowing out of the heat exchange of the indoor unit flows to the heat exchange part 41 at the bottom through the separator, the other part flows to the other heat exchange part 41 through the seventh pipeline 44, the fifth valve 45 and the liquid separator, the refrigerant flowing out of the top heat exchange part 41 flows to the four-way valve after the heat exchange part 41 exchanges heat, and the refrigerant flowing out of the other heat exchange part 41 flows to the first four-way valve 2 through the eighth pipeline 46, the sixth valve 47 and the fourth throttling part 48 and then returns to the compressor 1. The fourth throttling member 48 throttles the refrigerant flowing out of the heat exchanger 41, and can increase the pressure of the refrigerant flowing out of the heat exchanger 41 below, and reduce the refrigerant flow rate of the heat exchanger 41 below, so that the heat exchanger 41 below is less likely to frost. Particularly, when the outdoor unit is an top-outlet type, the air quantity flowing through the heat exchange member 41 at the top is large, and the air quantity corresponding to the unit refrigerant flow is almost the same through the adjustment of the fourth throttling part 48, so that the heat exchange of each part of the outdoor heat exchanger 4 is fully utilized, the overall heat exchange performance of the outdoor heat exchanger 4 is improved, and the heat exchange is more stable.

It should be noted that when the heat pump system is used for refrigerating, the fourth valve 43 is opened, the fifth valve 45 and the sixth valve 47 are closed, so that the plurality of heat exchange pieces 41 are connected in series, the supercooling degree of the refrigerant is increased, the two-phase enthalpy difference of the refrigerant is larger, the effect of the heat pump system is improved, and the overall refrigerating performance is improved; in the heating process using the heat pump system, the fourth valve 43 is closed, the fifth valve 45 and the sixth valve 47 are opened, so that the plurality of heat exchange pieces 41 are connected in parallel, the heat exchange pieces 41 are subjected to throttling adjustment of the fourth throttling part 48, so that the pressure of the refrigerant flowing through the bottom heat exchange piece 41 is increased, the flow is reduced, the evaporation temperature of the bottom heat exchange piece 41 is higher than that of the top heat exchange piece 41, and the bottom heat exchange piece 41 is not easy to frost.

Further, the outdoor heat exchanger 4 further includes a plurality of liquid distributors disposed in one-to-one correspondence with the heat exchanging elements 41, and the liquid distributors are disposed at one side of the heat exchanging elements 41 close to the indoor unit. The liquid separator can distribute the refrigerant flowing on the liquid separator, so that the refrigerant of each branch of each heat exchange piece 41 is more uniform, and the heat exchange effect is improved.

The invention also provides a control method for the heat pump system, which is characterized by comprising the following steps: the heat pump system is in a refrigeration mode, the first throttling part 61 is regulated, and the second throttling part 62 is opened to the maximum; the heat pump system is in heating mode, the second throttle member 62 is adjusted, and the first throttle member 61 is opened.

The invention also provides a control method for the heat pump system, which is characterized by comprising the following steps: the heat pump system is in a refrigeration mode, the first throttling part 61 is regulated, and the second throttling part 62 is opened to the maximum; the heat pump system is in heating mode, the second throttle member 62 is adjusted, and the first throttle member 61 is opened.

As can be appreciated by those skilled in the art, in the technical solution of the present invention, a heat pump system includes: the compressor 1, the first four-way valve 2, the indoor heat exchanger 3 and the outdoor heat exchanger 4 are sequentially arranged on the main loop; the outdoor heat exchanger 4 is connected with the compressor 1 through the first four-way valve 2; wherein, the device also comprises a gas-liquid separator 5 and a valve group 6; the valve group 6 includes: a first throttle member 61 provided in a first pipe 64, a first end of the first pipe 64 being connected to the gas-liquid separator 5, and a second end of the first pipe 64 being connected to the indoor heat exchanger 3; a second throttle member 62 provided in a second pipe 65, a first end of the second pipe 65 being connected to the gas-liquid separator 5, and a second end of the second pipe 65 being connected to the outdoor heat exchanger 4; and a second four-way valve 63 connected to the first pipe 64 and the second pipe 65, wherein the second four-way valve 63 is disposed near the first end of the first pipe 64 and near the second end of the second pipe section. The invention improves the problems of unbalanced refrigeration and heating capacity and difficult liquid separation of the two-phase refrigerant after heat exchange in the heat pump system in the prior art into the problems of unbalanced refrigeration and heating capacity and difficult liquid separation of the two-phase refrigerant by respectively throttling the first throttling part 61 and the second throttling part 62 and then separating the liquid in the refrigeration and heating paths.

Thus far, the technical solution of the present invention has been described in connection with the preferred embodiments shown in the drawings, but it is easily understood by those skilled in the art that the scope of protection of the present invention is not limited to these specific embodiments. Equivalent modifications and substitutions for related technical features may be made by those skilled in the art without departing from the principles of the present invention, and such modifications and substitutions will fall within the scope of the present invention.

Claims (10)

1. A heat pump system, comprising: the device comprises a compressor, a first four-way valve, an indoor heat exchanger, an outdoor heat exchanger and a gas-liquid separator;

wherein the heat pump system further comprises a valve group;

the valve group includes:

the first throttling component is arranged on a first pipeline, a first end of the first pipeline is connected with the gas-liquid separator, and a second end of the first pipeline is connected with the indoor heat exchanger;

the second throttling component is arranged on a second pipeline, the first end of the second pipeline is connected with the gas-liquid separator, and the second end of the second pipeline is connected with the outdoor heat exchanger;

a second four-way valve comprising a first side, a second side, a third side, and a fourth side;

the first side and the second side are connected to the first pipeline, the third side and the fourth side are connected to the second pipeline, and the second four-way valve is arranged close to the first end of the first pipeline and close to the second end of the second pipeline section.

2. The heat pump system of claim 1, wherein the valve train further comprises a first valve disposed in the third conduit;

the first end of the third pipeline is connected with the first side of the first throttling component on the first pipeline, and the third pipeline is connected with the second side of the first throttling component on the first pipeline.

3. The heat pump system of claim 1, wherein the valve train further comprises a second valve disposed in a fourth line;

the first end of the fourth pipeline is connected with the first end of the second throttling component, and the fourth pipeline is connected with the second end of the second throttling component.

4. The heat pump system of claim 1, wherein the valve train further comprises a third valve disposed in a fifth line, a first end of the fifth line being connected to the gas-liquid separator, a second end of the fifth line being connected to the compressor; and/or

The valve group further comprises: and the third throttling component is arranged on the fifth pipeline and is arranged between the gas-liquid separator and the third valve.

5. The heat pump system of claim 2, wherein the first valve is a one-way valve that allows only liquid-phase refrigerant to flow from the gas-liquid separator to the indoor heat exchanger.

6. A heat pump system according to claim 3, wherein the second valve is a one-way valve allowing only liquid-phase refrigerant to flow from the gas-liquid separator to the outdoor heat exchanger.

7. The heat pump system of claim 4, wherein the third valve is a check valve that allows only gas phase refrigerant to flow from the gas-liquid separator to the compressor.

8. The heat pump system of claim 1, wherein the outdoor heat exchanger comprises

The outdoor heat exchanger comprises a plurality of heat exchange pieces which are sequentially arranged from top to bottom, two adjacent heat exchange pieces are connected through a sixth pipeline, a first end of each heat exchange piece at the top is connected with the first four-way valve, and a first end of each heat exchange piece at the bottom is connected with the indoor heat exchanger;

a fourth valve provided on the sixth pipeline;

a seventh pipe having a first end connected to the heat exchange member except the bottom heat exchange member and a second end connected to the indoor heat exchanger;

a fifth valve provided on the seventh pipe;

an eighth pipeline, the first end of which is connected with the heat exchange piece except the bottom heat exchange piece, and the second end of which is connected with the first four-way valve;

a sixth valve provided on the eighth pipe;

and a fourth throttling part arranged on the eighth pipeline.

9. A control method for the heat pump system according to claim 1, characterized in that the control method comprises the steps of:

under the condition that the heat pump system is in a refrigeration mode, the opening degree of the first throttling component can be adjusted, and the second throttling component is fully opened;

the refrigerant subjected to heat exchange by the outdoor heat exchanger enters the gas-liquid separator after being throttled by the first throttling component, and the separated liquid refrigerant is subjected to heat exchange by the indoor heat exchanger through the second throttling component in a fully opened state; and/or

Under the condition that the heat pump system is in a heating mode, the opening degree of the second throttling component can be adjusted, so that the first throttling component is fully opened;

and the refrigerant subjected to heat exchange by the indoor heat exchanger enters the gas-liquid separator after being throttled by the second throttling component, and the separated liquid refrigerant is subjected to heat exchange by the outdoor heat exchanger through the first throttling component in a fully opened state.

10. A control method for the heat pump system according to claim 6, characterized by comprising the steps of:

under the condition that the heat pump system is in a refrigeration mode, the fourth valve is opened, the fifth valve and the sixth valve are closed, and the refrigerant completes heat exchange of the outdoor unit;

the opening degree of the first throttling component is adjustable, and the second throttling component is fully opened;

the refrigerant subjected to heat exchange by the outdoor heat exchanger enters the gas-liquid separator after being throttled by the first throttling component, and the separated liquid refrigerant is subjected to heat exchange by the indoor heat exchanger through the second throttling component in a fully opened state; and/or

Under the condition that the heat pump system is in a heating mode, the opening degree of the second throttling component can be adjusted, so that the first throttling component is fully opened;

and the refrigerant subjected to heat exchange by the outdoor heat exchanger enters the gas-liquid separator after being throttled by the second throttling component, and the liquid refrigerant subjected to separation is subjected to heat exchange by the outdoor heat exchanger through the first throttling component in a fully opened state.

And closing the fourth valve, opening the fifth valve and the six valves, and finishing heat exchange of the outdoor unit by the refrigerant.