CN108361807A - A kind of heat pump system and its control method - Google Patents

Abstract

The invention belongs to the technical field of heat pump units, and specifically provides a heat pump system and a control method thereof. The invention aims to solve the problem of insufficient heat supply of the existing heat pump system. The heat pump system of the present invention includes a first heat exchanger, a heat exchange end, and a water inlet pipeline and an outlet pipeline arranged between the first heat exchanger and the heat exchange end. The water outlet pipeline is provided with a first solenoid valve and an electric auxiliary In the heating device, a bypass pipeline is arranged between the water inlet pipeline and the water outlet pipeline, and a second electromagnetic valve is arranged on the bypass pipeline. The control method of the present invention includes: opening the valve body of the first solenoid valve and closing the valve body of the second solenoid valve; obtaining the required temperature of the heat exchange end; when the required temperature is greater than the first temperature threshold, turning on the electric auxiliary heating device, so that The target temperature is obtained at the end of the heat exchange; when the required temperature is less than or equal to the first temperature threshold, the electric auxiliary heating device is selectively turned on. When heat is supplied by the heat pump system, the heat supplied by the air-conditioning unit and the electric auxiliary heating device can be used to provide heat, which improves the total heat supply of the heat pump system.

Description

A heat pump system and its control method

technical field

The invention belongs to the technical field of heat pump units, and specifically provides a heat pump system and a control method thereof.

Background technique

The working principle of the heat pump unit is the same as that of the compression refrigerator. The four-way reversing valve of the air conditioner is used to change the work of the evaporator and condenser to achieve the purpose of cooling or heating.

When the air conditioner cools down in summer, it operates under refrigeration conditions, and the high-pressure steam discharged from the compressor enters the second heat exchanger (used as a condenser) through the four-way reversing valve. When heating in winter, first turn the four-way reversing valve to the working position of the heat pump, and the high-temperature and high-pressure refrigerant vapor discharged from the compressor flows into the first heat exchanger (used as a condenser) after passing through the four-way reversing valve, and the refrigerant steam The heat released during condensation is used to supply heat to the end of the heat exchange to achieve the purpose of indoor heating. The condensed liquid refrigerant enters the second heat exchanger (used as an evaporator) through the throttling device to absorb external heat and evaporate. The final steam passes through the four-way reversing valve and is sucked by the compressor to complete the heating cycle.

However, most of the heat pump units currently used for heating/cooling in the user’s life, when heating in winter, the maximum temperature provided by the heat pump system to the heat exchange end is not enough to meet the needs of users, resulting in poor use of the heat pump unit in winter, reducing user experience.

Correspondingly, the art needs a heat pump system and its control method to solve the above problems.

Contents of the invention

In order to solve the above-mentioned problems in the prior art, that is, to solve the problem of insufficient heat supply of the existing heat pump system, on the one hand, the present invention provides a heat pump system, including an air conditioning unit and a heat exchange terminal, the air conditioning unit includes a first A heat exchanger, a heat exchange pipeline is arranged between the heat exchange terminal and the first heat exchanger, and the feature is that the heat pump system further includes an electric auxiliary heat device, and the electric auxiliary heat device is arranged on the The heat exchange pipeline is located downstream of the first heat exchanger.

In the preferred technical solution of the above-mentioned heat pump system, the heat exchange pipeline includes a water inlet pipeline and a water outlet pipeline, and a first electromagnetic valve is also arranged on the water outlet pipeline, and the electric auxiliary heating device is arranged on the water outlet pipeline. and located between the first solenoid valve and the first heat exchanger.

In a preferred technical solution of the above-mentioned heat pump system, the heat exchange pipeline further includes a bypass pipeline, the first end of the bypass pipeline communicates with the water inlet pipeline, and the second end of the bypass pipeline communicates with the water inlet pipeline. The second end communicates with the water outlet pipeline, wherein the second end is located between the first solenoid valve and the electric auxiliary heating device.

In a preferred technical solution of the above heat pump system, a second solenoid valve is provided on the bypass pipeline, so that when the first solenoid valve body is opened and the second solenoid valve body is closed, the first solenoid valve The heat exchanger, the heat exchange pipeline and the heat exchange end form a loop.

In a preferred technical solution of the above heat pump system, the electric auxiliary heating device is an annular electric heater.

On the other hand, the present invention also provides a control method of a heat pump system, the control method comprising the following steps: opening the first solenoid valve body and closing the second solenoid valve body; obtaining the required temperature of the heat exchange terminal ; Judging whether to turn on the electric auxiliary heating device according to the required temperature.

In the preferred technical solution of the above heat pump system control method, the step of "judging whether to turn on the electric auxiliary heating device according to the required temperature" further includes: comparing the required temperature with the first temperature threshold; when the required temperature > the first temperature When the threshold is reached, the electric auxiliary heating device is turned on, so that the heat exchange end can obtain a target temperature through the heating operation of the air conditioning unit and the electric auxiliary heating device.

In the preferred technical solution of the control method of the above-mentioned heat pump system, "when the required temperature>the first temperature threshold, turn on the electric auxiliary heat device so that the heat exchange terminal passes through the air conditioning unit and the electric auxiliary heat The step of obtaining the target temperature through the heating operation of the device" further includes: when the first temperature threshold < demand temperature < second temperature threshold, turn on the electric auxiliary heating device so that the heat exchange terminal passes through the air conditioner The heating operation of the unit and the electric auxiliary heating device obtains the required temperature.

In the preferred technical solution of the control method of the above-mentioned heat pump system, "when the required temperature>the first temperature threshold, turn on the electric auxiliary heat device so that the heat exchange terminal passes through the air conditioning unit and the electric auxiliary heat The step of obtaining the target temperature through the heating operation of the device" further includes: when the required temperature>the second temperature threshold, turn on the electric auxiliary heating device, so that the heat exchange terminal passes through the air conditioning unit and the electric auxiliary heating device. The heating operation of the auxiliary heating device obtains the second temperature threshold.

In the preferred technical solution of the control method of the above-mentioned heat pump system, the step of "judging whether to turn on the electric auxiliary heating device according to the required temperature" further includes: when the required temperature ≤ the first temperature threshold, selectively turning on the An electric auxiliary heating device, so that the heat exchange terminal obtains the required temperature only through the heating operation of the air conditioning unit, or obtains the required temperature through the heating operation of the air conditioning unit and the electric auxiliary heating device .

Those skilled in the art can understand that, in the preferred technical solution of the present invention, by setting the electric auxiliary heat device on the heat exchange pipeline of the heat pump system and setting the electric auxiliary heat device downstream of the first heat exchanger, the heat pump When the heat is supplied to the system, the heating and heating of the air conditioner unit and the heating of the electric auxiliary heating device can be used to increase the total amount of heat supplied by the heat pump system to the heat exchange end, thereby increasing the maximum temperature of the outlet water at the heat exchange end. value, improving the user experience of the heat pump system. By judging whether to turn on the electric auxiliary heating device according to the demand temperature of the heat exchange terminal, on the one hand, the heat supply temperature of the heat pump system to the heat exchange terminal is increased, and on the other hand, the heat supply efficiency of the heat pump system can be accelerated.

Description of drawings

Describe preferred embodiment of the present invention below with reference to accompanying drawing, in the accompanying drawing:

Fig. 1 is a system schematic diagram of a heat pump system according to an embodiment of the present invention;

Fig. 2 is a schematic diagram of the system during heating operation of the heat pump system according to an embodiment of the present invention;

Fig. 3 is a schematic flowchart of a control method of a heat pump system according to an embodiment of the present invention;

Fig. 4 is a schematic diagram of the heat pump system in cooling operation according to an embodiment of the present invention.

List of reference signs:

1. Heat exchange terminal; 2. First heat exchanger; 3. Heat exchange pipeline; 31. Water inlet pipeline; 32. Water outlet pipeline; 321. First solenoid valve; 33. Bypass pipeline; 331. The first 2. Solenoid valve; 4. Electric auxiliary heating device; 5. Compressor; 6. High pressure switch; 7. One-way valve; 8. Four-way reversing valve; 9. High pressure liquid receiver; 10. Electronic expansion valve; 11. The second heat exchanger; 12, the low pressure switch; 13, the gas-liquid separator.

Detailed ways

Those skilled in the art should understand that the embodiments in this section are only used to explain the technical principle of the present invention, and are not used to limit the protection scope of the present invention. For example, although the components in the drawings are drawn according to a certain proportion, the proportion is not static, and those skilled in the art can make adjustments to it according to the needs, so as to adapt to specific applications. The adjusted technology The scheme will still fall within the protection scope of the present invention.

It should be noted that, in the description of the present invention, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" etc. Terms indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are merely for convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, Therefore, it should not be construed as limiting the invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and should not be construed as indicating or implying relative importance.

In addition, it should be noted that, in the description of the present invention, unless otherwise clearly stipulated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a It is a detachable connection or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediary, and it may be the internal communication of two components. Those skilled in the art can understand the specific meanings of the above terms in the present invention according to specific situations.

As shown in FIG. 1 , FIG. 1 is a system diagram of a heat pump system according to an embodiment of the present invention. Referring to Figure 1, the heat pump system includes an air-conditioning unit and a heat exchange terminal 1, the air-conditioning unit includes a first heat exchanger 2, a heat exchange pipeline 3 is arranged between the heat exchange terminal 1 and the first heat exchanger 2, and the heat exchange pipeline 3 is provided with an electric auxiliary heating device 4 , and the electric auxiliary heating device 4 is located downstream of the first heat exchanger 2 . In the case of heat supply by the heat pump system, the air-conditioning unit heats and supplies heat while increasing the heat of the electric auxiliary heating device, which increases the heat supply of the heat pump system to the heat exchange end and improves the user experience of the heat pump system. Setting the electric auxiliary heat device downstream of the first heat exchanger can make full use of the heat of the first heat exchanger and the electric auxiliary heat device, and prevent the medium in the heat exchange end from obtaining the heat of the electric auxiliary heat device before entering the second heat exchanger. When the heat exchange of a heat exchanger may not reach the required heat at the end of the heat exchange, the air conditioning unit will shut down for protection due to excessive pressure, thus stopping the heat supply.

Continuing to refer to FIG. 1, the heat exchange pipeline 3 includes a water inlet pipeline 31 and a water outlet pipeline 32. The first electromagnetic valve 321 is arranged on the water outlet pipeline 32. Between the valve 321 and the first heat exchanger 2, so that the medium at the heat exchange terminal 1 flows through the first heat exchanger 2 for heat exchange, then passes through the electric auxiliary heat device 4 to further absorb heat, and finally flows back to the The heat exchange terminal 1 completes the heat exchange cycle. Through such arrangement, the heat provided by the first heat exchanger and the electric auxiliary heat device is fully utilized, and the heat supply efficiency of the heat pump system is improved.

Continuing to refer to Fig. 1, the heat exchange pipeline 3 also includes a bypass pipeline 33, the right end of the bypass pipeline 33 communicates with the water inlet pipeline 31, and the left end of the bypass pipeline 33 communicates with the water outlet pipeline 32 and is located in the first solenoid valve. Between the valve 321 and the electric auxiliary heating device 4. Wherein, the bypass pipeline 33 is provided with a second solenoid valve 331, so that when the valve body of the first solenoid valve 321 is opened and the valve body of the second solenoid valve 331 is closed, the first heat exchanger 2, the heat exchange pipeline 3 and the The heat exchange end 1 forms a circuit, and when the valve body of the first electromagnetic valve 321 is closed and the valve body of the second electromagnetic valve 331 is opened, the first heat exchanger 2 , the heat exchange pipeline 3 and the bypass pipeline 33 form a bypass circuit.

It should be noted that, when the valve body of the first electromagnetic valve and the valve body of the second electromagnetic valve are opened, the pipelines are connected, and when they are closed, the pipelines are blocked.

Specifically, the electric auxiliary heating device 4 may be a ring electric heater. It can be understood that the electric auxiliary heating device can also be other devices that can provide heat to the heat exchange pipeline, and those skilled in the art can choose a reasonable electric auxiliary heating device, such as an electric heating plate, according to actual conditions and needs.

As shown in FIG. 2 , FIG. 2 is a system schematic diagram of the heat pump system in heating operation according to an embodiment of the present invention. Referring to Figure 2, the air conditioner unit also includes a compressor 5, a high-pressure switch 6, a one-way valve 7, a four-way reversing valve 8, a high-pressure liquid reservoir 9, an electronic expansion valve 10, a second heat exchanger 11, a low-pressure switch 12, Gas-liquid separator 13. When the heat pump system is heating, the heating operation process of the air conditioning unit is as follows: the four-way reversing valve 8 switches to the heating mode, and the compressor 5 passes the high-temperature and high-pressure gaseous refrigerant through the high-pressure switch 6 and the one-way valve 7 into the In the four-way reversing valve 8, and enter the pipeline leading to the first heat exchanger 2 from the valve port of the four-way reversing valve 8, the high-pressure gaseous refrigerant liquefies and dissipates heat in the first heat exchanger 2 (at this time, the first heat exchanger 2 A heat exchanger is used as a condenser), and then it becomes a high-pressure liquid and enters the high-pressure liquid receiver 9, and then becomes a low-pressure liquid refrigerant after being throttled and depressurized by the electronic expansion valve 10, enters the second heat exchanger 11, and enters the second heat exchanger 11. Vaporization and heat absorption in the heat exchanger 11 (the second heat exchanger is used as an evaporator at this time), and then it becomes a low-pressure gaseous state and leads to the four-way reversing valve 8, and comes out from the valve port of the four-way reversing valve 8 and then passes through the low-pressure switch 12 enters the gas-liquid separator 13, and finally returns to the compressor 5, and the air-conditioning unit completes the heating cycle. During the heating process of the air conditioner unit, the medium in the heat exchange end 1 of the heat pump system enters the first heat exchanger 2 through the water inlet pipe 31 and exchanges heat. At this time, the valve body of the first electromagnetic valve 321 is opened, and the second electromagnetic valve The valve body of the valve 331 is closed, and the medium flows out from the first heat exchanger 2 into the water outlet pipe 32 after the heat exchange is completed, then flows through the electric auxiliary heating device 4 and absorbs the heat provided by the electric auxiliary heating device 4, and finally passes through the water outlet pipe 32 To heat exchange end 1, to provide heat for users. In the case of heat supply by the heat pump system, the air-conditioning unit heats and supplies heat while increasing the heat of the electric auxiliary heating device, which increases the heat supply of the heat pump system to the heat exchange end and improves the user experience of the heat pump system.

It should be noted that the second heat exchanger is installed in the outdoor unit as an outdoor heat exchanger, and the first heat exchanger can be installed outdoors or in the outdoor unit together with the second heat exchanger according to the actual installation situation, or The situation installs the first heat exchanger indoors. Those skilled in the art can reasonably set the installation position of the first heat exchanger according to the actual installation situation and needs.

As shown in Fig. 2 and Fig. 3, Fig. 3 is a schematic flowchart of a control method of a heat pump system according to an embodiment of the present invention. Referring to Fig. 2 and Fig. 3, the control method of the heat pump system includes the following steps:

S10. Opening the valve body of the first solenoid valve and closing the valve body of the second solenoid valve;

S20. Acquiring the required temperature of the heat exchange terminal;

S30. Determine whether to turn on the electric auxiliary heating device according to the required temperature.

Specifically, the valve body of the first solenoid valve 321 is opened and the valve body of the second solenoid valve 331 is closed, so that the heat exchanging terminal 1, the water inlet pipeline 31, the first heat exchanger 2 and the water outlet pipeline 32 form a loop, so that the heat exchanger The medium in the hot end 1 can smoothly enter the first heat exchanger 2 for heat exchange and return to the heat exchange end 1 . It should be noted that the required temperature at the heat exchange end is actually the outlet water temperature set by the user at the heat exchange end.

Specifically, step S30, judging whether to turn on the electric auxiliary heating device according to the required temperature, further includes: comparing the required temperature with the first temperature threshold; The target temperature is obtained through the heating operation of the air conditioning unit and the electric auxiliary heating device.

Wherein, the first temperature threshold is the highest temperature threshold that the original system can make the outlet water temperature at the heat exchange end reach when the heat pump system is not provided with an electric auxiliary heating device. In the original system, when it is detected that the outlet water temperature at the heat exchange end is greater than or equal to the maximum temperature threshold (ie, the first temperature threshold), the air conditioning unit will shut down for protection due to excessive pressure and end the heating. After adding an electric auxiliary heat device downstream of the first heat exchanger of the heat pump system, although the maximum heat that the air conditioner unit can provide remains unchanged, the total heat that the heat pump system can provide increases with the heat from the electric auxiliary heat device, which can make The outlet water temperature at the heat exchange end becomes higher to meet the higher temperature demand of users.

Specifically, when the first temperature threshold<required temperature<second temperature threshold, the electric auxiliary heating device is turned on so that the heat exchange end can obtain the required temperature through the heating operation of the air conditioning unit and the electric auxiliary heating device. When the required temperature>the second temperature threshold, the electric auxiliary heating device is turned on so that the heat exchanging end obtains the third temperature threshold through the heating operation of the air conditioner unit and the electric auxiliary heating device, and the third temperature threshold ≤ the second temperature threshold.

Wherein, the second temperature threshold is the highest temperature threshold that the heat pump system with the electric auxiliary heating device can make the outlet water temperature at the heat exchange end reach. The third temperature threshold is a preset temperature threshold ≤ the second temperature threshold. When the actual temperature at the end of the heat exchange is equal to the third temperature threshold, the electric auxiliary heating device and the heat pump air conditioner unit are turned off to avoid damage to the air conditioner due to excessive pressure. The unit produces damage, which improves the reliability and stability of the heat pump system.

Preferably, when the required temperature is greater than the second temperature threshold, the electric auxiliary heating device is turned on, so that the heat exchanging end obtains the second temperature threshold through the heating operation of the air conditioning unit and the electric auxiliary heating device. In addition, when it is detected that the actual outlet water temperature at the heat exchange end is greater than or equal to the second temperature threshold (ie, the maximum temperature threshold), the electric auxiliary heating device and the heat pump air-conditioning unit are turned off to avoid damage to the air-conditioning unit due to excessive pressure. Through such setting, on the basis of ensuring the reliable operation of the heat pump system, the user's demand for heat can be satisfied to the greatest extent, and the user experience is improved. It can be understood that those skilled in the art may also take other protection measures according to actual conditions and needs. As an example, when the required temperature>the second temperature threshold, in order to protect the reliable operation of the heat pump system, the electric auxiliary heating device and the heat pump air conditioner unit may also be directly turned off.

It should be noted that the maximum temperature threshold is a floating value due to uncertain factors during the operation of the air-conditioning unit. When determining the second temperature threshold, the average value of multiple maximum temperature thresholds can be taken in advance as the second temperature threshold. It can be understood that those skilled in the art can also choose a reasonable method to determine the second temperature threshold according to actual conditions and needs.

Specifically, step S30, judging whether to turn on the electric auxiliary heating device according to the required temperature, further includes: selectively turning on the electric auxiliary heating device when the required temperature≤the first temperature threshold. Since when the demand temperature ≤ the first temperature threshold, only the heat provided by the air conditioner unit can meet the heat required to reach the demand temperature. Therefore, when the demand temperature ≤ the first temperature threshold, you can choose not to turn on the electric auxiliary The hot end gets the required temperature only through the heating operation of the air conditioning unit. Or turn on the electric auxiliary heating device, so that the heat exchange end can obtain the required temperature through the joint heating operation of the air conditioning unit and the electric auxiliary heating device, so as to improve the heating efficiency of the heat pump system.

It can be seen that the control method of the heat pump system of the present invention includes opening the first solenoid valve body and closing the second solenoid valve body; obtaining the required temperature of the heat exchange end; judging whether to open the electric auxiliary heating device according to the required temperature. When the heat pump system is used to supply heat, the heat supply of the electric auxiliary heating device is increased, so that the total amount of heat supplied by the heat pump system to the heat exchange end is increased, and the user experience of the heat pump system is improved. Further, when the required temperature is greater than the first temperature threshold, the electric auxiliary heating device is turned on, so that the air conditioner unit and the electric auxiliary heating device jointly heat and supply heat, and the maximum temperature of the outlet water at the heat exchange end can be increased. Furthermore, when the actual outlet water temperature at the heat exchange end is greater than or equal to the second temperature threshold, the air-conditioning unit is shut down, avoiding damage to the air-conditioning unit due to excessive temperature, and improving the reliability and stability of the heat pump system. Furthermore, when the required temperature ≤ the first temperature threshold, the electric auxiliary heating device is selectively turned on to improve the heating efficiency of the heat pump system.

Because the air conditioning unit of the heat pump system is in the process of heating operation, the fins of the second heat exchanger (the second heat exchanger is used as an evaporator at this time) will form a frost layer due to the evaporation and heat absorption of the refrigerant and the low outdoor temperature. . In this case, the air conditioner needs to turn on the defrosting mode, that is, switch from the heating mode to the cooling mode, as shown in FIG. 4 , which is a system schematic diagram of the heat pump system in cooling operation according to an embodiment of the present invention. Referring to Figure 4, the cooling and defrosting operation process of the air conditioning unit is as follows: the four-way reversing valve 8 switches to the cooling mode, and the compressor 5 passes the high-temperature and high-pressure gaseous refrigerant into the four-way reversing valve through the high-pressure switch 6 and the one-way valve 7. into the valve 8, and enter the pipeline leading to the second heat exchanger 11 from the valve port of the four-way reversing valve 8, and the high-pressure gaseous refrigerant liquefies and dissipates heat in the second heat exchanger 11, and the second heat exchanger 11 The fins heat up to melt the frost to achieve the effect of defrosting. The high-pressure gaseous refrigerant turns into a high-pressure liquid after heat dissipation and liquefaction, and then becomes a low-pressure liquid refrigerant after being throttled and reduced by the electronic expansion valve 10, and then passed into the high-pressure liquid receiver 9 , and then enter the first heat exchanger 2 and vaporize and absorb heat in the first heat exchanger 2, then become a low-pressure gaseous state and lead to the four-way reversing valve 8, and come out from the valve port of the four-way reversing valve 8 and then pass through the low-pressure The switch 12 enters the gas-liquid separator 13, and finally returns to the compressor 5, and the air-conditioning unit completes the refrigeration cycle.

Specifically, the heat pump system includes an air conditioning unit, and the defrosting control method of the heat pump system includes the following steps: closing the first solenoid valve body and opening the second solenoid valve body; opening the electric auxiliary heating device, and making the air conditioning unit enter the defrosting frost pattern. Specifically, the valve body of the first electromagnetic valve 321 is closed and the valve body of the second electromagnetic valve 331 is opened, the heat exchange terminal 1 is cut off, and the water inlet pipeline 31, the first heat exchanger 2, the water outlet pipeline 32 and the bypass The line 33 forms a bypass circuit.

Since the first heat exchanger 2 needs to absorb heat as an evaporator when the defrosting mode is turned on, the temperature of the first heat exchanger 2 drops. The effect of a heat exchanger 2 on the temperature of the heat exchanging terminal 1 improves the thermal comfort of the user's room. At the same time, turn on the electric auxiliary heating device 4 in the defrosting mode, so that the medium in the bypass circuit absorbs the heat of the electric auxiliary heating device 1 and circulates in the bypass circuit, and the medium with heat flows to the first heat exchanger 2, heat can be provided to the first heat exchanger 2, so that the process of heat absorption and vaporization of the low-pressure liquid refrigerant passing into the first heat exchanger 2 is accelerated, and the total heat absorbed is also increased, leading to the second heat exchanger 2. The total heat of the heater 11 becomes faster and more, which speeds up the whole defrosting process and improves the defrosting efficiency of the air conditioning unit. Moreover, since the medium with heat has been circulating in the first heat exchanger 2, after the defrosting is completed, the temperature in the first heat exchanger 2 will not drop too much. When the defrosting is completed and the heating mode is entered, Initially, the influence on the temperature of the heat exchange terminal 1 is small, which further improves the indoor thermal comfort.

The second heat exchanger 11 of the air conditioning unit includes a defrosting sensor. During the defrosting process, the temperature of the defrosting sensor of the second heat exchanger 11 gradually rises, and the temperature of the defrosting sensor is obtained to determine whether the temperature of the defrosting sensor is high. At the first set temperature for the first set time, when the temperature of the defrosting sensor is higher than the first set temperature for the first set time, it is determined that the air conditioner completes the defrosting. It should be noted that the first set temperature and the first set time are also preset before the air conditioner leaves the factory.

After the defrosting is completed, the air conditioner unit exits the defrosting mode and the valve body of the first electromagnetic valve 321 is opened and the valve body of the second electromagnetic valve 331 is closed, so that the heat exchange terminal 1, the water inlet pipeline 31, the first exchange valve The heater 2 and the water outlet pipeline 32 form a loop, and the heating mode is resumed.

It should be noted that the method for judging whether defrosting is completed is not limited to the methods described in the above-mentioned embodiments, and a differential pressure gauge defrosting controller can also be set. The high voltage connection of the differential pressure gauge defrosting controller is The air inlet side of the surface of the second heat exchanger is connected to the air outlet side of the surface of the second heat exchanger at low pressure. After the second heat exchanger is frosted, the airflow resistance increases, and the front-to-back pressure difference changes; after the frost melts, the airflow resistance decreases, and the front-to-back pressure difference returns to normal, so it is judged that the defrosting is completed. It can be understood that those skilled in the art can set a reasonable method for judging whether to complete the defrosting according to the actual situation and needs.

It can be seen that the defrosting control method of the heat pump system of the present invention includes closing the first solenoid valve body and opening the second solenoid valve body; opening the electric auxiliary heating device, and making the air conditioning unit enter the defrosting mode. Through such arrangement, the influence of the first heat exchanger on the temperature of the heat exchange terminal is reduced, the thermal comfort of the user's room is improved, the defrosting process is accelerated, and the defrosting efficiency of the air conditioning unit is improved. In addition, the defrosting control method further includes: judging whether the defrosting is completed; when the defrosting is completed, opening the first solenoid valve body and closing the second solenoid valve body. With such a setting, after the defrosting is completed, the system immediately resumes the circulation loop in the heating mode, which improves the switching efficiency between the defrosting mode and the heating mode.

So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings, but those skilled in the art will easily understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to relevant technical features, and the technical solutions after these changes or substitutions will all fall within the protection scope of the present invention.

Claims (10)

1. a kind of heat pump system, including air-conditioner set and heat exchange end, the air-conditioner set includes First Heat Exchanger, the heat exchange It is provided with heat exchanging pipe between end and the First Heat Exchanger, which is characterized in that the heat pump system further includes the auxiliary hot charging of electricity It sets, the auxiliary thermal of electricity is set to the heat exchanging pipe and the downstream positioned at the First Heat Exchanger.

2. heat pump system according to claim 1, which is characterized in that the heat exchanging pipe includes inlet pipeline and outlet pipe Road, the first solenoid valve is additionally provided on the outlet pipeline, and the auxiliary thermal of electricity is set to the outlet pipeline and is located at institute It states between the first solenoid valve and the First Heat Exchanger.

3. heat pump system according to claim 2, which is characterized in that the heat exchanging pipe further includes bypass line, described The first end of bypass line is connected to the inlet pipeline, and the second end of the bypass line is connected to the outlet pipeline,

Wherein, the second end is between first solenoid valve and the auxiliary thermal of electricity.

4. heat pump system according to claim 3, which is characterized in that it is provided with second solenoid valve on the bypass line, To be opened in first electromagnetic valve body, when the second solenoid valve valve body is closed, the First Heat Exchanger, the heat exchange Pipeline and heat exchange end forming circuit.

5. heat pump system according to any one of claim 1 to 4, which is characterized in that the auxiliary hot charging of electricity is set to annular Electric heater.

6. a kind of control method of heat pump system, which is characterized in that the control method includes the following steps：

So that the first electromagnetic valve body is opened and second solenoid valve valve body is made to be closed；

Obtain the demand temperature of heat exchange end；

Judged whether to open the auxiliary thermal of electricity according to the demand temperature.

7. control method according to claim 6, which is characterized in that " judged whether to open electricity according to the demand temperature The step of auxiliary thermal ", further comprises：

Compare demand temperature and the first temperature threshold；

When demand temperature the first temperature thresholds of ＞, the auxiliary thermal of electricity is opened, it is described to make the heat exchange end pass through Air-conditioner set and the heating operation of the auxiliary thermal of electricity obtain target temperature.

8. control method according to claim 7, which is characterized in that " when demand temperature the first temperature thresholds of ＞, open The auxiliary thermal of electricity, to make the heat exchange end be obtained by the heating operation of the air-conditioner set and the auxiliary thermal of electricity The target temperature " the step of further comprise：

When the first temperature threshold ＜ demand temperature ＜ second temperature threshold values, the auxiliary thermal of electricity is opened, to make described change Hot end obtains the demand temperature by the air-conditioner set and the heating operation of the auxiliary thermal of electricity.

9. control method according to claim 7, which is characterized in that " when demand temperature the first temperature thresholds of ＞, open The auxiliary thermal of electricity, to make the heat exchange end be obtained by the heating operation of the air-conditioner set and the auxiliary thermal of electricity The target temperature " the step of further comprise：

When demand temperature ＞ second temperature threshold values, the auxiliary thermal of electricity is opened, it is described to make the heat exchange end pass through Air-conditioner set and the heating operation of the auxiliary thermal of electricity obtain the second temperature threshold value.

10. control method according to claim 7, which is characterized in that " judged whether to open institute according to the demand temperature State the auxiliary thermal of electricity " the step of further include：

When demand temperature≤first temperature threshold, it is selectively opened the auxiliary thermal of electricity, to make the heat exchange end The demand temperature is only obtained by the heating operation of the air-conditioner set, or

The demand temperature is obtained by the air-conditioner set and the heating operation of the auxiliary thermal of electricity.