KR20180078073A - Heat Pump For a Vehicle - Google Patents

Abstract

The present invention relates to a heat pump for a vehicle, and more specifically, to a heat pump for a vehicle including a double loop having a refrigerant loop and a cooling water loop and configured to perform cooling/heating/defrosting/dehumidifying operations by using the double loop. An embodiment of the present invention provides a double loop type heat pump for a vehicle including a first fluid line, through which a first fluid flows, and a second fluid line, through which a second fluid flows, wherein a compressor, a first direction switching valve, an internal heat exchanger, a first expansion unit, a second direction switching valve, a gas/liquid separating unit, an external heat exchanger, a second expansion unit, a third heat exchanger, and an accumulator are disposed on the first fluid line, the first fluid is supplied to the first expansion unit after passing through the internal heat exchanger through driving of the first direction switching valve or is supplied directly to the first expansion unit without passing through the internal heat exchanger, and the second fluid is supplied to the external heat exchanger after passing through the gas/liquid separating unit through driving of the second direction switching valve and is supplied directly to the external heat exchanger without passing through the gas/liquid separating unit.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a heat pump for a vehicle,

The present invention relates to a heat pump for an automobile, and more particularly, to a heat pump for an automobile, which is composed of a secondary-loop including a coolant loop and a cooling water loop, and performs a cooling / heating / defrosting / The present invention relates to an automotive heat pump.

In recent years, along with the demand for improvement of the global environment and the atmospheric environment, the demand for introduction of automobiles or low pollution vehicles powered by alternative energy sources is increasing.

As a vehicle using alternative energy, an electric vehicle using a battery and an electric motor, and a hybrid vehicle using an electric motor and an engine as a drive source are attracting attention.

In a general internal combustion engine using gasoline, diesel, or the like as a raw material, heating operation can be performed using a heat source from an internal combustion engine. However, in the case of an electric vehicle, an engine or cooling water is not provided as a heating source, At the level of technology development to date, there is a technical difficulty that the driving distance of the vehicle is drastically reduced when the battery is heated. Even in a hybrid vehicle, there is a motor driving mode in which the engine is stopped and driven only by an electric motor. In this section, the vehicle needs to travel only at the capacity of the battery, so that a sufficient heat source may not be secured at the time of heating as in an electric vehicle. Therefore, when an air conditioner installed in an automobile that uses a general engine for an electric vehicle and a hybrid vehicle is directly applied, there arises a problem that the heat source at the time of heating operation and the compressor driving force at the time of cooling operation are not sufficiently provided.

In order to overcome this problem, it is necessary to overcome the limitations of the conventional heating and cooling apparatus for cooling and heating the electric vehicle or the hybrid vehicle in such a case. As one of the measures to overcome this problem, the heat pump, A method for applying the present invention to a display device is proposed.

A heat pump refers to absorbing low temperature heat and moving the absorbed heat to high temperature. In one example, the heat pump has a cycle in which the liquid refrigerant evaporates in the evaporator, takes heat away from the evaporator, becomes a gas, and is again liquefied while releasing heat to the surroundings by the condenser. When this is applied to an electric vehicle or a hybrid vehicle, there is an advantage that a heat source insufficient for a conventional air conditioner can be secured.

Of course, there have been attempts to apply heat pumps to automobiles.

Korean Patent Laid-Open Publication No. 10-2000-0063254 discloses a heat pump comprising: a hot water heater as a heat pump which is installed on the downstream side of an air circulation unit and circulates cooling water of an engine; an air heater provided on the upstream side of the air circulation unit, A first bypass line for bypassing the refrigerant discharged from the compressor in the heating operation, and a second bypass line provided outside the air circulation unit for discharging the refrigerant discharged from the hot water heater A first electronic expansion valve disposed at a refrigerant inlet side of the indoor heat exchanger and a second electronic expansion valve disposed at a refrigerant inlet side of the dual pipe heat exchanger, Discloses a heat pump having an expansion valve and control means for controlling the opening degree of the first electronic expansion valve and the second electronic expansion valve It was.

In addition, Korean Patent Registration No. 10-1669826 discloses a refrigerant circulation system including a compressor installed on a refrigerant circulation line for compressing and discharging a refrigerant, and a heat exchanger installed inside the air conditioner case for exchanging heat between the air in the air conditioner case and the refrigerant discharged from the compressor An outdoor heat exchanger installed inside the air conditioner case for exchanging heat between the air in the air conditioner case and the refrigerant supplied to the compressor; an outdoor heat exchanger installed outside the air conditioner case for exchanging heat between the refrigerant circulating through the refrigerant circulation line and the outside air; A first expansion means provided on a refrigerant circulation line between the indoor heat exchanger and the outdoor heat exchanger for expanding the refrigerant; a second expansion means provided on the refrigerant circulation line at the inlet side of the evaporator for expanding the refrigerant; , And an inlet-side refrigerant circulation line of the second expansion means and an outlet-side refrigerant circulation line of the evaporator And a bypass line through which the refrigerant bypasses the second expansion means and the evaporator in the heat pump mode, wherein the refrigerant circulation line is provided with a bypass line for performing a dehumidification in the passenger compartment And a dehumidifying line for supplying a part of the refrigerant circulating in the refrigerant circulation line to the evaporator side is provided, wherein the dehumidifying line connects the outlet refrigerant circulation line of the first expansion means and the inlet refrigerant circulation line of the evaporator And a portion of the refrigerant passing through the first expansion means and before entering the outdoor heat exchanger is provided to the evaporator side.

According to these prior art vehicle heat pumps, it is possible to optimally control cooling and heating, and also to perform a dehumidifying operation smoothly in a vehicle interior. However, all of these inventions have various modes such as cooling / heating / Many bypass lines and valves are configured for operation to form a very complex system. Furthermore, in an environment where the outside air temperature is extremely low (for example, during winter), the external heat exchanger can be easily conceived. In order to remove the external heat exchanger, a complicated refrigerant defrost loop including a bypass line is used to remove the refrigerant.

When a large number of bypass lines and valves are constructed as in the prior art, the assembling and manufacturing processes of the heat pump system are complicated and the pressure drop of the refrigerant increases along the complicated line, There arises a problem that the refrigerant loop control for each operating mode becomes complicated. There is controversy as to whether the advantages of the heat pump system can be overcome due to the complexity of the control and the increase of the cost.

As long as there is a limitation on the battery for a vehicle, it is obvious that a conventional air conditioner should be modified or an air conditioner of a new concept should be developed.

There is a need to develop a new air conditioner suitable for electric cars or hybrid cars in keeping with the development of alternative energy, which is a trend of the times.

In addition, there is also a need to easily configure the air conditioning system to keep pace with the trend of downsizing and compacting of automobile equipment and components in order to improve the fuel efficiency of automobiles.

In order to meet such a demand, the present invention eliminates unnecessary bypass lines as an embodiment of the present invention, thereby avoiding the structural and control complexity of the conventional heat pump system. Thereby providing a heat pump system constituting a loop.

Particularly, when the heating operation is started when the outside air temperature is low, frost is conceived in the external heat exchanger, and the heat exchange in the external heat exchanger is not smooth due to the frost conceived, resulting in a problem of lowering the heating performance . Accordingly, the present invention proposes a heat pump construction and a heat pump operation method that prevent frost formation on the external heat exchanger while maintaining the heating performance when the outside air temperature is low.

According to an aspect of the present invention, there is provided a secondary-loop type vehicle comprising a first fluid line through which a first fluid flows and a second fluid line through which a second fluid flows, A heat pump comprising: a compressor having a compressor, a first direction switching valve, an internal heat exchanger, a first expansion means, a second direction switching valve, a gas-liquid separating means, an external heat exchanger, a second expansion means, And an accumulator is disposed in the first expansion valve and the first fluid is supplied to the first expansion means through the internal heat exchanger by driving the first direction switching valve or directly to the first expansion means without passing through the internal heat exchanger. And the second fluid is supplied to the external heat exchanger without passing through the gas-liquid separating means or passed through the gas-liquid separating means to the external heat exchanger by driving to the second direction switching valve A heat pump for an automobile.

According to one embodiment, the heat pump is used in an electric vehicle and a hybrid vehicle.

According to one embodiment, the first fluid may be a refrigerant, and the second fluid may be a cooling water.

According to an embodiment of the present invention, the first opening / closing valve and the cabin cooler are disposed in the first branch line of the second fluid line, and the second open / close valve and the waste heat recovery unit are disposed in the second branch line.

According to an embodiment, in the cooling mode, the first direction switching valve allows the first fluid to be directly supplied to the first expansion means without passing through the internal heat exchanger.

According to an embodiment, the first directional control valve may be configured to allow the first fluid to be supplied to the first expansion means through the internal heat exchanger in a heating mode, a defrost mode, and a dehumidification-heating mode.

According to an embodiment, the second directional control valve is configured to supply the first fluid to the external heat exchanger directly without passing through the gas-liquid separating means in the cooling mode and the defrost mode.

According to an embodiment, the second directional control valve is configured to allow the first fluid to be supplied to the external heat exchanger through the gas-liquid separating means in the heating mode and the dehumidifying-heating mode.

According to an embodiment of the present invention, the first expansion means and the second expansion means are electronic expansion means formed to be capable of selectively opening the refrigerant line fully.

According to another embodiment of the present invention, there is provided a method for controlling a flow rate of a fluid, comprising: a first fluid line through which a first fluid flows; a compressor; a first direction switching valve; an internal heat exchanger; a first expansion means; a second direction switching valve; Wherein the first fluid is supplied to the first expansion means through the internal heat exchanger by driving the first direction switching valve or through the internal heat exchanger without passing through the internal heat exchanger Liquid separating means and is supplied to the first expansion means, and the second fluid is supplied to the external heat exchanger through the gas-liquid separating means by driving to the second direction switching valve, Wherein the first fluid and the second fluid are supplied to an external heat exchanger, wherein the first fluid and the second fluid are supplied to a cooling mode, a heating mode, a defrost mode Wherein the first fluid flows through the gas-liquid separating means and flows through the first fluid in the liquid phase and the first fluid in the vapor phase in the dehumidifying-heating mode, , And only the first fluid in the liquid phase flows into the external heat exchanger. The present invention also provides a method of operating an automotive heat pump.

In the present invention, the invention has been proposed in which the bypass line of the heat pump system is minimized.

In the conventional heat pump system, the assembling and manufacturing processes are complicated for driving the heat pump mode, the pressure drop of the refrigerant is increased, and the refrigerant loop control for each operation mode is difficult. In particular, when the outside air temperature is low, frost is conceived in the external heat exchanger. In the conventional heat pump system, the defrosting operation is performed by using a complicated refrigerant loop in order to remove the frost. For example, in the conventional technology, the refrigerant at mid-high temperature and high pressure passing through the internal heat exchanger flows through the expansion valve and the bypass line by the chiller (third heat exchanger) without passing through the external heat exchanger.

However, the present invention proposes a heat pump system that is shorter in length than a conventional heat pump system and has a shorter refrigerant loop length, and is superior in defrosting efficiency to the prior art. It has a technical advantage of reducing the cost because the bypass line is omitted and the cost is reduced and the refrigerant loop length is short so that the pressure drop amount is reduced and the internal heat exchanger is circulated to the external heat exchanger The defrost performance is improved and the defrosting time can be shortened. In addition, it has an advantage that the heating performance is prevented from being reduced during the defrosting operation.

From the control point of view, the present invention is a dual loop system, so temperature control can be individually performed for each loop, which is advantageous in terms of system stability. In the case of a system failure diagnosis, There are advantages.

Further, when the heating operation is started when the outside air temperature is low, frost is conceived on the external heat exchanger, thereby solving the problem that the heating performance is deteriorated. Liquid separation is performed before the first fluid is introduced into the external heat exchanger in the heating operation mode or the dehumidification-heating operation mode of the heat pump, so that only the liquid fluid flows in the external heat exchanger, thereby raising the evaporation temperature in the external heat exchanger. As a result, the heating of the outer surface of the external heat exchanger is delayed and the heat exchange performance is improved, so that the heating performance is improved.

1 is a view showing a first fluid and a second fluid circulation path in a cooling operation mode in the construction of a heat pump system having a double loop according to an embodiment of the present invention.
FIG. 2 is a view showing a first fluid and a second fluid circulation path in a heating operation mode in the construction of a heat pump system having a dual loop according to an embodiment of the present invention.
3 is a view showing a first fluid and a second fluid circulation path in the defrost operation mode in the construction of a heat pump system having a double loop according to an embodiment of the present invention.
FIG. 4 is a view showing a first fluid and a second fluid circulation path in a heating-dehumidifying operation mode in a configuration of a heat pump system having a dual loop according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an automotive heat pump according to the present invention will be described in detail with reference to the accompanying drawings. The embodiments are provided so that those skilled in the art can easily understand the technical spirit of the present invention, and thus the present invention is not limited thereto. In addition, the matters described in the attached drawings may be different from those actually implemented by the schematic drawings to easily describe the embodiments of the present invention.

The expression "including" any element is merely referred to as being an "open" expression and should not be understood as excluding the additional elements.

Further, when a component is referred to as being connected or connected to another component, it may be directly connected or connected to the other component, but it should be understood that there may be other components in between.

Also, the expressions such as 'first, second', etc. are used only to distinguish a plurality of configurations, and do not limit the order or other features between configurations.

1 to 4, an automotive heat pump system and a heat pump operation method according to the present invention will be described. 1 is a view showing a first fluid and a second fluid circulation path in a cooling operation mode in the construction of a heat pump system having a double loop according to an embodiment of the present invention. FIG. 2 is a view showing a first fluid and a second fluid circulation path in a heating operation mode in the construction of a heat pump system having a dual loop according to an embodiment of the present invention. 3 is a view showing a first fluid and a second fluid circulation path in the defrost operation mode in the construction of a heat pump system having a double loop according to an embodiment of the present invention. 4 is a view showing a first fluid and a second fluid circulation path in the dehumidification-heating operation mode in the construction of a heat pump system having a double loop according to an embodiment of the present invention.

First, the structure of a heat pump for a vehicle according to an embodiment of the present invention is as follows. The main feature of the heat pump of the present invention is that it is composed of a secondary-loop. In the case of a dual-loop configuration, configurations on a first fluid line (line 1) through which a first fluid flows and configurations on a second fluid line (line 2) through which a second fluid flows. When the vehicle of the present invention is an electric vehicle, the first fluid and the second fluid may denote different refrigerants. In the case of a hybrid vehicle, the first fluid may be a refrigerant and the second fluid may be a refrigerant or a coolant different from the first fluid. It can mean. Preferably, the first fluid may be a refrigerant provided for air conditioning of a passenger compartment, and the second fluid may be a cooling water line flowing into a vehicle through a water pump (PUMP).

The heat pump system of the present invention may be applied to an electric vehicle that does not have an internal combustion engine using fossil fuel but that is driven only by a battery and a hybrid vehicle that is equipped with an internal combustion engine and a battery. According to an embodiment of the present invention, when the heat pump system of the present invention is applied to the electric vehicle, a cooling water line for cooling the engine is not separately provided. Therefore, the second fluid is preferably a refrigerant other than cooling water.

A heat pump for an automobile according to an embodiment of the present invention includes a secondary fluid line (line 1) through which a first fluid flows and a second fluid line (line 2) through which a second fluid flows, a first direction switching valve, an internal heat exchanger, a first expansion means, a second direction switching valve, a gas-liquid separating means, an external heat exchanger, and a second heat exchanger are provided on the first fluid line (line 1) The first opening and closing valve 240 and the cabin cooler 140 are arranged in the first branch line (line 2-1) of the second fluid line (line 2), the second expansion means, the third heat exchanger and the accumulator And the second open / close valve 250 and the waste heat recovery unit 150 may be disposed in the second branch line (line 2-2) of the second fluid line (line 2).

More specifically, on the first fluid line (line 1) through which the first fluid flows, a compressor (COMP) for compressing and discharging the first fluid; An internal heat exchanger (110) for heat-exchanging the first fluid with air in the passenger compartment; An external heat exchanger (120) for heat-exchanging the first fluid with outside air; A first expansion means (220) disposed on a first fluid line between the internal heat exchanger (110) and the external heat exchanger (120), the first expansion means (220) being arranged to expand the first fluid; Liquid separating means (300) for separating only the liquid in the first fluid flowing into the external heat exchanger (120) and flowing it to the external heat exchanger (120); A second expansion means (230) disposed on the first fluid line, the second expansion means being arranged to expand the first fluid passing through the external heat exchanger (120); An accumulator (ACC) for introducing gaseous refrigerant in the liquid phase and gaseous phase refrigerant on the first fluid line passing through the second expansion means (230) into the compressor; A third heat exchanger 130 disposed on the first fluid line 1 between the second expansion means 230 and the accumulator ACC and capable of heat exchange with the second fluid is disposed.

The second fluid line (line 2) through which the second fluid flows is connected to a cabin cooler 140 that performs heat exchange with the air in the passenger compartment and is connected to a waste heat recovery unit The first fluid line (line 2) may be connected to the first open / close valve 240 and the waste heat recovery unit 150 for opening / closing the flow to / from the cabin cooler 140, (Or intermittently) the second open / close valve 250 may be provided.

The heat pump of the present invention further includes a first direction switching valve 210 for switching the flow direction of the first fluid discharged from the compressor COMP and a first fluid passing through the first expansion means 220, And a second direction switching valve 260 for directly supplying the gas to the gas-liquid separating means 300 or supplying it to the gas-liquid separating means 300.

1, a compressor COMP, a directional control valve 210, an internal heat exchanger 110, a first expansion means 220, a second directional control valve 260, and a second directional control valve 260 are disposed on a first fluid line (line 1) A first fluid part 131 of the third heat exchanger 130 and an accumulator ACC are provided in the first fluid passage 130. The first fluid part 131 and the second fluid part 131 of the second fluid On the line 2, a second fluid part 132 of the third heat exchanger 130, a pump, a first opening / closing valve 240, a cabin cooler 140, a second opening / closing valve 250, A recovery unit 150 is provided.

The first directional control valve 210 provided on the first fluid line line 1 supplies the first fluid discharged from the compressor COMP to the internal heat exchanger 110 side according to the air conditioning mode of the vehicle, To the external heat exchanger (120) without passing through the heat exchanger (110). For this purpose, the first directional control valve 210 may be a 3-way valve. When the first directional control valve 210 is a 3-way valve, the operation of supplying the first fluid to the external heat exchanger 120 and the operation of supplying the first fluid to the internal heat exchanger 110 may be selectively performed .

Further, a pressure sensor (not shown) is mounted on the first fluid line (line 1) connecting the compressor COMP and the first directional control valve 210 so that the refrigerant discharged from the compressor COMP in a compressed state Pressure can be detected.

Specifically, the first direction switching valve 210 allows the first fluid to be directly supplied to the first expansion means 220 without passing through the internal heat exchanger 110 in the cooling mode. At this time, the high-temperature and high-pressure first fluid discharged from the compressor (COMP) passes through the first expansion means (220) and evaporates in the external heat exchanger (120). Meanwhile, the first directional control valve 210 allows the first fluid to be supplied to the first expansion means 220 through the heat exchanger 110 in the heating mode, the defrost mode, and the dehumidification-heating mode. At this time, since the first fluid of high temperature and high pressure discharged from the compressor COMP is condensed while passing through the internal heat exchanger 110, the temperature is lowered, and the first fluid after being condensed passes through the first expansion means 220, And flows into the heat exchanger 120 side.

The second directional control valve 260 of the present invention can directly supply the first fluid to the external heat exchanger 120 or to the gas-liquid separating means 300 according to the air conditioning mode of the vehicle. In the cooling mode and the defrost mode, the first fluid flows directly into the external heat exchanger 120 without passing through the gas-liquid separating means 300. In the heating mode and the dehumidifying-heating mode, the first fluid flows into the gas- And then flows into the external heat exchanger 120 indirectly.

More specifically, in the heating mode and the dehumidification-heating mode, only the first fluid is separated from the liquid first fluid and the gaseous first fluid after the first fluid is passed through the gas-liquid separator 300, And the first fluid in the gaseous state bypasses the external heat exchanger 120 and flows directly into the second expansion means 230. [ In this process, only the first liquid in the liquid phase flows into the external heat exchanger 120, so that the evaporation temperature of the external heat exchanger 120 is raised, which prevents or delays frost congestion in the external heat exchanger. This improves the heat exchange performance and ultimately improves the heating performance.

The second directional control valve 260 may also be a 3-way valve. Operation in which the first fluid is directly supplied to the external heat exchanger 120 when the second directional control valve 260 is a 3-way valve and operation in which the first fluid is supplied via the gas-liquid separating means 300 Can be made selectively.

The gas-liquid separating means 300 of the present invention plays a role similar to that of the accumulator ACC. However, in the case of the gas-liquid separating means 300, the first fluid introduced from one side is separated into a gas phase and a liquid phase, Liquid separator 300 is a means for discharging the liquid first fluid to the external heat exchanger 120 while the accumulator ACC is a means for separating the gas phase and the liquid phase from the downstream end of the external heat exchanger 120 The first fluid is discharged to the compressor COMP, and the first fluid is stored or discharged to the outside.

On the other hand, the cabin cooler 140 and the waste heat recovering unit 150 provided on the second fluid line (line 2) are configured in parallel, and the first open / close valve 240, the second open / close valve 250, The second fluid can selectively flow toward the cabin cooler 140 and the waste heat recovering unit 150 by the opening and closing operation. However, in some cases, the first opening / closing valve 240 and the second opening / closing valve 250 may be opened at the same time, and the second fluid may flow simultaneously to the cabin cooler 140 and the waste heat recovering unit 150. That is, the temperature of the second fluid can be changed by selectively providing the waste heat source.

According to the embodiment, the waste heat recovery unit 150 may collect waste heat from electrical equipment or recover waste heat from the cabin. Here, the electrical component connected to the waste heat recovery unit 150 may mean a product that can generate heat, such as a motor M, an inverter, a converter, a battery, or the like. The waste heat of the cabin connected to the waste heat recovery unit 150 means all kinds of waste heat provided inside and outside the cabin room, for example, heating means separately provided for heating, This may be the solar panel that recovers.

The third heat exchanger 130 of the present invention may be divided into a first fluid side part 131 and a second fluid side part 132. [ The third heat exchanger 130 receives two different fluids and transmits thermal energy of the respective fluids. Since no separate heat providing means is connected to the third heat exchanger 130, the third heat exchanger 130 Heat will be transferred from a fluid with a hotter temperature to a fluid with a colder temperature. The fluid flowing in the third heat exchanger 130 is configured not to be mixed with each other. For this purpose, the shape of the third heat exchanger 130 is preferably formed like a chiller widely used as a cooler.

The function of the second fluid line (line 2) is to move the heat of the hot second fluid to the cooler first fluid side through the third heat exchanger 130 during cooling, thereby cooling the cabin cooler 140 side, And collects the waste heat at the time of heating to transfer heat to the first fluid side through the third heat exchanger 130. At the time of the advanced heating, the waste heat and / or the heat of the cabin side are recovered together, 3 heat exchanger (130).

Hereinafter, an operation method of a heat pump for an automobile according to the present invention will be described in detail with reference to the drawings.

According to the operation method of the automotive heat pump of the present invention, the compressor (COMP), the first direction switching valve (210), the internal heat exchanger (110), the first fluid line The second expansion valve 230, the third heat exchanger 130 and the accumulator ACC are connected to the expansion valve 220, the second direction switching valve 260, the gas-liquid separator 300, the external heat exchanger 120, The first fluid is supplied to the first expansion means 220 through the internal heat exchanger 110 by driving the first direction switching valve 210 or through the internal heat exchanger 110 And the second fluid is supplied to the external heat exchanger 120 through the gas-liquid separating means 300 by driving the second direction switching valve 260 Liquid separator (300), and is directly supplied to the external heat exchanger (120) without passing through the gas-liquid separator (300). Wherein the controller performs the operation in any one of a cooling mode, a heating mode, a defrost mode, and a dehumidification-heating mode by connecting the flows of the first fluid and the second fluid to each other, wherein in the heating mode or the defrost mode, The first fluid passes through the gas-liquid separating means 300 and is separated into a liquid first fluid and a gaseous first fluid so that only the liquid first fluid flows to the external heat exchanger 120 .

The cooling mode, the heating mode, the defrost mode, the dehumidification-heating mode on / off, the switching and the temperature control of the present invention can be automatically adjusted and operated by the user's selection or the controller of the vehicle. Here, the controller may mean a conventional VCU (Vehicle Control Unit) provided in the vehicle.

The first expansion means 220 and the second expansion means 230 of the present invention may be electronic expansion means formed to selectively open the refrigerant line fully. The opening amount of the refrigerant line can be freely adjusted according to the input of the user or the controller. Unlike the mechanical expansion means in which the amount of opening is determined according to the piping shape and the pressure of the refrigerant line can not be freely adjusted.

The controller senses the pressure information of the first fluid received through the pressure sensor (not shown), the pressure information of the second fluid, the temperature of the first fluid and the second fluid received through the temperature sensor (not shown) The valves are driven to operate the compressors to adjust the opening of each of the expansion means and the opening / closing valve. In addition, the controller may control the flow rate of the water pump according to the air-conditioning mode of the vehicle and the temperature state of the electrical waste heat source, or may control the airflow of the opening / closing door and the blowing fan. The controller also determines whether the waste heat recovery unit is provided with the heat recovery and the heat quantity according to the heating load required by the vehicle or the vehicle air conditioning mode.

The cooling mode of the present invention will be described with reference to Fig.

As the cooling operation method, the first fluid is supplied to the compressor (COMP), the first expansion means 220, the external heat exchanger 120, the second expansion means 230, the third heat exchanger 130, the accumulator (ACC) The first expansion means 220 is fully opened and the second fluid is introduced into the third heat exchanger 130, the cabin cooler 140, the third heat exchanger 140, (130) in this order.

Here, the path of the first directional control valve 210 to the internal heat exchanger 110 side is closed and only the path directly connected to the external heat exchanger 120 side is opened.

The path to the gas-liquid separating means 300 side of the second direction switching valve 210 is closed and only the path directly connected to the external heat exchanger 120 side is opened. Accordingly, the high-temperature, high-pressure, and gaseous first fluid discharged from the compressor (COMP) flows directly to the external heat exchanger (120) through the first expansion means (220).

At this time, the first expansion means 220 is fully opened to minimize the pressure drop and the state change of the first fluid. Accordingly, the high-temperature, high-pressure, and gaseous first fluid discharged from the compressor COMP passes through the first expansion means 220 as it is, and is then condensed while being exchanged with the cool outside air by the external heat exchanger 120, The first fluid in the gas phase is converted into the first fluid in the liquid phase.

Subsequently, the first fluid having passed through the external heat exchanger 120 is decompressed and expanded in the process of passing through the second expansion means 230 to become a low-temperature, low-pressure liquid first fluid, and then flows into the third heat exchanger 130 .

The low-temperature low-pressure liquid phase first fluid introduced into the third heat exchanger 130 can heat-exchange with the second fluid on the second fluid line. At this time, the first fluid in the third heat exchanger 130 evaporates while exchanging heat with the second fluid, and at the same time, the second fluid is cooled by an endothermic effect due to the latent heat of evaporation, whereby the cooled second fluid flows to the cabin cooler 140 so that the air supplied by the blowing fan 11 is cooled to be cooled. In this process, the door 12 closes the air flow on the side of the internal heat exchanger 110, flows into the air conditioner case, and then meets the cabin cooler 140 and discharges the cooled air directly into the passenger compartment.

Thereafter, the first fluid, which has passed through the third heat exchanger 130 and is mixed with the low-temperature and low-pressure gaseous and liquid phases, passes through the accumulator ACC and flows back to the compressor COMP, thereby circulating the cycle. The accumulator ACC separates the liquid refrigerant and the gaseous refrigerant from the refrigerant supplied to the compressor COMP so that only the gaseous refrigerant can be supplied to the compressor COMP.

That is, in the cooling mode, the first fluid passes through the first expansion means 220 as it is discharged from the compressor, the first expansion means 220 is condensed in the external heat exchanger 120, the second expansion means 230 is decompressed, And evaporating in the third heat exchanger 130. The second fluid cools the inside of the vehicle by contacting with the air in a state in which heat is taken by the first fluid.

Referring to Fig. 2, the heating mode will be described.

As the heating operation method, the first fluid is supplied to the compressor (COMP), the internal heat exchanger 110, the first expansion means 220, the gas-liquid separation means 300, the external heat exchanger 120, the second expansion means 230, The third heat exchanger 130, the accumulator ACC, and the compressor COMP in this order. At this time, the second expansion means 230 is fully opened. And the second fluid is passed through the third heat exchanger 130, the waste heat recovering unit 150, and the third heat exchanger 130 in this order.

Here, the path to the internal heat exchanger 110 side is opened by driving the first direction switching valve 210, and the path directly connected to the external heat exchanger 120 side is closed. Therefore, the high temperature, high pressure, and gaseous first fluid discharged from the compressor flows into the internal heat exchanger 110 side.

The first fluid of high temperature, high pressure and gaseous phase introduced into the internal heat exchanger 110 is condensed while exchanging heat with the air blown into the air conditioning case through the blowing fan 11 to convert the gaseous first fluid into a liquid first fluid do. The air passing through the internal heat exchanger 110 is converted into a warm air and then supplied to the interior of the vehicle to heat the inside of the interior of the vehicle.

The first fluid passed through the internal heat exchanger 110 is decompressed and expanded through the first expansion means 220 to become a low-pressure first fluid.

In the heating mode, the path directly connected to the external heat exchanger 120 side is closed by driving the second direction switching valve 210, and only the path to the gas-liquid separating means 300 side is opened.

The gas fluid and liquid phase are mixed in the low-pressure first fluid introduced into the gas-liquid separating means 300, and the gas-liquid separating means 300 separates the gas and liquid and discharges them to the other. The separated first fluid is supplied to the external heat exchanger 120. The first fluid in the liquid phase in the external heat exchanger 120 evaporates and meets with the gaseous first fluid discharged from the gas-liquid separating means 300 to the downstream end of the external heat exchanger 120. The first fluid in a low-temperature, low-pressure gas-liquid mixture state passes through the third heat exchanger 130 and flows into the accumulator (ACC).

At this time, the second expansion means 230 is fully opened and does not affect the state change of the first fluid.

The first fluid introduced into the third heat exchanger 130 may be heat-exchanged with the second fluid on the second fluid line (line 2). The heat exchange may be selectively performed, and the first fluid exchanges heat in the form of receiving heat from the second fluid in order to improve the heating performance by mainly increasing the temperature of the first fluid. For example, when the outdoor temperature is a low temperature state at a predetermined temperature (for example, -10 ° C or lower), the heating performance due to the flow of the first fluid and the operation mode High) heating mode) so as to satisfy the heating load required for the vehicle.

At this time, the first fluid in the third heat exchanger 130 can be heat-exchanged with the second fluid and can receive heat from the second fluid. Referring to FIG. 2, the second fluid serves to recover the waste heat and to supply heat to the first fluid through the third heat exchanger 130. To this end, the first on-off valve 240 on the second fluid line (line 2) is closed to block the flow of the second fluid on the cabin cooler 140 side, and the second on-off valve 250 is opened, So that the second fluid can flow only toward the first fluid passage 150 side.

The first fluid, which is relatively low in temperature, low in pressure, and mixed with the gas phase and the liquid phase when introduced into the third heat exchanger 130, becomes a first fluid having a relatively high temperature, low pressure and a mixed gas phase and liquid phase, . As a result, the efficiency of the compressor (COMP) is increased and the heating efficiency is increased.

 In this process, the door 12 opens the air flow on the side of the internal heat exchanger 110, introduces into the air conditioning case, and then meets the internal heat exchanger 110 to discharge hot air into the passenger compartment.

That is, in the heating mode, the first fluid is discharged from the compressor COMP, condensed in the internal heat exchanger 110, reduced in pressure expansion in the first expansion means 220, gas-liquid separation in the gas-liquid separation means 300, Evaporated in the external heat exchanger 120, passed through the completely opened second expansion means 230, and passed through the selective heat exchange process in the third heat exchanger 130 in sequence. And the second fluid serves to provide waste heat to the first fluid.

Referring to Fig. 3, the defrost mode will be described.

As the defrosting operation method, the first fluid is supplied to the compressor (COMP), the internal heat exchanger 110, the first expansion device 220, the external heat exchanger 120, the second expansion device 230, the third heat exchanger 130 ), The accumulator (ACC), and the compressor (COMP) in this order, the first expansion means (220) is fully opened and the second fluid is introduced into the third heat exchanger (130) (150) and / or the second waste heat recovering unit (170), and the third heat exchanger (130).

If the outside air is very cold in the above-described heating operation mode, there may arise a problem that frost is concealed on the surface due to the endothermic action of the external heat exchanger 120. If the defrost mode shown in FIG. 3 is temporarily applied, It is possible to prevent the frost from being frosted or to remove frost frost.

Here, the path of the directional control valve 210 to the internal heat exchanger 110 side is opened and the path directly connected to the external heat exchanger 120 side is closed. Therefore, the high temperature, high pressure, and gaseous first fluid discharged from the compressor flows into the internal heat exchanger 110 side.

The first fluid of high temperature, high pressure and gaseous phase introduced into the internal heat exchanger 110 is partially condensed while exchanging heat with the air blown into the air conditioning case through the air blowing fan 11 so that the gaseous first fluid flows into the first fluid Can be converted.

Subsequently, the first expansion means 220, located on the path through which the first fluid flows, is fully open to minimize the pressure drop and state change of the first fluid. The first fluid that has passed through the internal heat exchanger 110 can be condensed once again while exchanging heat with the outside air in the external heat exchanger 120.

At this time, since the first fluid maintains a certain amount of heat at a high temperature when it is discharged from the compressor COMP, it is possible to prevent the frost concealment in the external heat exchanger 120 or to remove frost frost. In other words, the refrigerant passing through the internal heat exchanger 110 is circulated to the external heat exchanger 120 at a medium-temperature high-pressure state without expanding, thereby exhibiting an improved defrosting ability. The defrosting time can be shortened by exerting the defrosting effect through simple valve operation without passing through a separate bypass line for defrosting.

The first fluid passing through the external heat exchanger 120 is decompressed and expanded while being passed through the second expansion means 230 to be brought into the low temperature, low pressure and liquid state, and then flows into the third heat exchanger 130 side. In the third heat exchanger 130, it is evaporated by the second fluid and converted into a low-temperature and low-pressure gas and liquid state, and flows into the accumulator ACC side.

Here, the second fluid may pass through the waste heat recovering unit 150 to transfer the waste heat to the first fluid, so that the evaporating action in the third heat exchanger 130 may be more actively performed.

That is, in the defrosting mode, the first fluid is discharged from the compressor, condensed in the internal heat exchanger 110, passed through the fully opened first expansion means 220, re-condensed in the external heat exchanger 120, The second expansion means 230 and the third heat exchanger 130, and the second fluid provides waste heat to the first fluid.

In the defrosting mode of the present invention, the operation of switching the flow direction of the first fluid is not accompanied, so that the amount of power consumption consumed in the operation of switching the flow direction can be reduced and frequent valve opening / And vibration and noise due to the vibration are reduced. Most of all, it is very simple and effective to configure and control the heat pump.

In addition, conventionally, a method has been mainly used in which the heating of the vehicle is temporarily stopped during the defrosting operation or the fluid flow cycle is reversed to temporarily reduce the heating performance. However, according to the present invention, since the first expansion means 220 is fully opened during the heating and the second expansion means 230 is switched so as to perform the expansion under reduced pressure, the interior of the vehicle can be continuously heated Therefore, the present invention has the advantage of preventing the phenomenon that the heating performance is temporarily reduced.

Referring to FIG. 4, the dehumidification-heating mode will be described.

As the dehumidification-heating operation method, the first fluid is supplied to the compressor (COMP), the internal heat exchanger 110, the first expansion means 220, the gas-liquid separation means 300, the external heat exchanger 120, 230, the third heat exchanger 130, the accumulator ACC, and the compressor COMP in this order. At this time, the second expansion means 230 is fully opened. And the second fluid is passed through the third heat exchanger 130, the cabin cooler 140, and the third heat exchanger 130 in this order.

Here, the path to the internal heat exchanger 110 side is opened by driving the first direction switching valve 210, and the path directly connected to the external heat exchanger 120 side is closed. Therefore, the high temperature, high pressure, and gaseous first fluid discharged from the compressor flows into the internal heat exchanger 110 side.

The first fluid of high temperature, high pressure and gaseous phase introduced into the internal heat exchanger 110 is condensed while exchanging heat with the air blown into the air conditioning case through the blowing fan 11 to convert the gaseous first fluid into a liquid first fluid do. The air passing through the internal heat exchanger 110 is converted into a warm air and then supplied to the interior of the vehicle to heat the inside of the interior of the vehicle.

The first fluid having passed through the internal heat exchanger 110 is decompressed and expanded through the first expansion means 220 to become a low pressure liquid first fluid and then supplied to an external heat exchanger 120 serving as an evaporator. Here, the path directly connected to the external heat exchanger 120 side is closed by driving the second direction switching valve 210, and only the path to the gas-liquid separator 300 side is opened.

The gas fluid and liquid phase are mixed in the low-pressure first fluid introduced into the gas-liquid separating means 300, and the gas-liquid separating means 300 separates the gas and liquid and discharges them to the other. The separated first fluid is supplied to the external heat exchanger 120. The first fluid in the liquid phase in the external heat exchanger 120 evaporates and meets with the gaseous first fluid discharged from the gas-liquid separating means 300 to the downstream end of the external heat exchanger 120. The first fluid in a low-temperature, low-pressure gas-liquid mixture state passes through the third heat exchanger 130 and flows into the accumulator (ACC).

At this time, the second expansion means 220 is fully opened and does not affect the state change of the first fluid.

The first fluid introduced into the third heat exchanger 130 may be heat-exchanged with the second fluid on the second fluid line (line 2). At this time, the second fluid in the third heat exchanger 130 may be heat-exchanged with the first fluid, and may be heated by the first fluid. The cooled second fluid may be supplied to the cabin cooler 140 side to cool the air supplied by the blowing fan.

That is, in the dehumidification-heating mode, the first fluid is discharged from the compressor, condensed in the internal heat exchanger 110, decompression expanded in the first expansion means 220, gas-liquid separation in the gas-liquid separation means 300, Passes through the evaporator in the heat exchanger 120, passes through the completely opened second expansion means 230 and passes through the heat exchanger 130 in the third heat exchanger 130. The second fluid is heat- And cools the inside of the vehicle.

The humid air introduced by the blowing fan is brought into contact with the surface of the cabin cooler 140 to be condensed, and then the air is introduced into the cabin cooler 140 to the side of the internal heat exchanger 110 which is in the heat-generating operation, so that dry air with moisture removed as a result is discharged into the passenger compartment.

As described above, according to the system of the present invention, a heat pump system that is shorter in length than the conventional heat pump system and shorter in length than the conventional heat pump system and superior in defrost efficiency to the prior art is proposed. It has a technical advantage of reducing the cost due to omission of the bypass line unlike the prior art and having a cost advantage in that the refrigerant loop length is short and the pressure drop amount is small and the internal heat exchanger does not expand the refrigerant past the internal heat exchanger, And can be circulated to the external heat exchanger, thereby improving defrost performance and shortening the time required for defrosting. In addition, it has an advantage that the heating performance is prevented from being reduced during the defrosting operation.

From the control point of view, since the present invention is a dual loop system, temperature control can be individually performed for each loop, which is advantageous in terms of system stability. Loops are dualized so that individual diagnosis can be done for each loop when a system fault diagnosis is made.

Further, when the heating operation is started when the outside air temperature is low, frost is conceived on the external heat exchanger, thereby solving the problem that the heating performance is deteriorated. Liquid separation is performed before the first fluid is introduced into the external heat exchanger in the heating mode or the dehumidification-heating mode operation of the heat pump, so that only the liquid fluid flows into the external heat exchanger, thereby raising the evaporation temperature in the external heat exchanger. As a result, the heating of the outer surface of the external heat exchanger is delayed and the heat exchange performance is improved, so that the heating performance is improved.

In the foregoing detailed description of the present invention, only specific embodiments thereof have been described. It is to be understood, however, that the invention is not to be limited to the specific forms thereof, which come within the scope of the appended claims, and all variations, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims Should be understood.

10: Air conditioning case (duct)
11: blowing fan
12: Door
110: internal heat exchanger
120: External heat exchanger
130: third heat exchanger
140: cabin cooler
150: waste heat recovery unit
210: first direction switching valve
220: first expansion means
230: second expansion means
240: first opening / closing valve
250: Second open / close valve
260: second direction switching valve
300: gas-liquid separation means

Claims (10)

A secondary-loop-type vehicle heat pump comprising a first fluid line through which a first fluid flows and a second fluid line through which a second fluid flows,
A compressor, a first direction switching valve, an internal heat exchanger, a first expansion means, a second direction switching valve, a gas-liquid separating means, an external heat exchanger, a second expansion means, a third heat exchanger, and an accumulator are disposed on the first fluid line. However,
The first fluid is supplied to the first expansion means directly through the internal heat exchanger by being driven by the first direction switching valve or supplied to the first expansion means without passing through the internal heat exchanger,
And the second fluid is supplied to the external heat exchanger without passing through the gas-liquid separating means and supplied to the external heat exchanger or the gas-liquid separating means by driving to the second direction switching valve. Heat pump.
The method according to claim 1,
Wherein the heat pump is used in an electric vehicle and a hybrid vehicle.
The method according to claim 1,
Wherein the first fluid is a refrigerant, and the second fluid is a cooling water.
The method according to claim 1,
Wherein a first open / close valve and a cabin cooler are disposed in a first branch line of the second fluid line, and a second open / close valve and a waste heat recovery unit are disposed in a second branch line.
The method according to claim 1,
Wherein the first directional control valve causes the first fluid to be directly supplied to the first expansion means without passing through the internal heat exchanger in the cooling mode.
The method according to claim 1,
Wherein the first directional control valve allows the first fluid to be supplied to the first expansion means through the internal heat exchanger in the heating mode, the defrost mode, and the dehumidification-heating mode.
The method according to claim 1,
And the second directional control valve causes the first fluid to be supplied directly to the external heat exchanger without passing through the gas-liquid separating means in the cooling mode and the defrost mode.
The method according to claim 1,
Wherein the second directional control valve allows the first fluid to be supplied to the external heat exchanger through the gas-liquid separating means in the heating mode and the dehumidifying-heating mode.
The method according to claim 1,
Wherein the first expansion means and the second expansion means are electronic expansion means formed so as to be capable of selectively opening the refrigerant line fully.
A first direction switching valve, an internal heat exchanger, a first expansion means, a second direction switching valve, a gas-liquid separating means, an external heat exchanger, a second expansion means, and a third heat exchange on a first fluid line through which the first fluid flows And an accumulator,
The first fluid is supplied to the first expansion means directly through the internal heat exchanger by being driven by the first direction switching valve or supplied to the first expansion means without passing through the internal heat exchanger,
And the second fluid is supplied to the external heat exchanger without passing through the gas-liquid separating means and supplied to the external heat exchanger or the gas-liquid separating means by driving to the second direction switching valve. A method of operating a heat pump,
Wherein the controller performs an operation in any one of a cooling mode, a heating mode, a defrost mode, and a dehumidification-heating mode by connecting the flows of the first fluid and the second fluid to each other,
In the heating mode or the dehumidifying-heating mode, the first fluid passes through the gas-liquid separating means to be separated into the liquid first fluid and the gaseous first fluid, and only the liquid first fluid flows into the external heat exchanger Wherein the control unit controls the operation of the heat pump.

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