阅读说明：本技术 一种热泵模块机组及其防冻控制方法 (Heat pump module unit and anti-freezing control method thereof ) 是由 王维兵 陈炳泉 杨伟 王彬 管祥华 李羲龙 楚毅 陈朋举 曹永根 李欣 董金运 于 2020-12-01 设计创作，主要内容包括：本发明公开了一种热泵模块机组及其防冻控制方法,其中防冻控制方法包括：接收进入防冻模式的信号；控制循环水泵运行,经过第一设定时间后获取循环水温度,根据不同的循环水温度采用不同级别的防冻运行模式。本发明在选择实际的防冻运行模式前首先控制循环水先循环一段时间,可使热泵模块机组中的水流动起来,检测的循环水温度较为真实,避免由于循环水回水管或者循环水出水管上设置传感器的位置由于局部低温造成的“假报警”情况发生,从而避免频繁启动防冻模式给热泵模块机组带来的负担,以及给用户造成的能耗负担。(The invention discloses a heat pump module unit and an anti-freezing control method thereof, wherein the anti-freezing control method comprises the following steps: receiving a signal for entering an anti-freezing mode; and controlling the circulating water pump to operate, acquiring the temperature of circulating water after a first set time, and adopting different levels of anti-freezing operation modes according to different temperatures of the circulating water. According to the invention, before the actual anti-freezing operation mode is selected, the circulating water is firstly controlled to circulate for a period of time, so that the water in the heat pump module unit can flow, the detected circulating water temperature is relatively real, and the condition of false alarm caused by local low temperature at the position of a sensor arranged on a circulating water return pipe or a circulating water outlet pipe is avoided, so that the load of the heat pump module unit and the energy consumption load of a user caused by frequently starting the anti-freezing mode are avoided.)

1. An anti-freezing control method of a heat pump module unit is characterized in that: comprises that

Receiving a signal for entering an anti-freezing mode;

and controlling the circulating water pump to operate, acquiring the temperature of circulating water after a first set time, and adopting different levels of anti-freezing operation modes according to different temperatures of the circulating water.

2. The antifreeze control method of a heat pump module unit as set forth in claim 1, wherein: before receiving the signal for entering the anti-freezing mode, the method comprises

Acquiring the ambient temperature and the shutdown time of the circulating water pump;

judging whether the environmental temperature is less than or equal to an environmental temperature threshold value or not, and whether the shutdown time of the circulating water pump reaches an anti-freezing time interval threshold value or not;

and if the judgment results are yes, sending the signal for entering the anti-freezing mode.

3. The antifreeze control method of a heat pump module unit according to claim 2, wherein:

judging whether the environment temperature is greater than or equal to the anti-freezing spacer ring temperature standard or not;

if so, taking a first anti-freezing time interval threshold as the anti-freezing time interval threshold;

if not, the second anti-freezing time interval threshold is taken as the anti-freezing time interval threshold;

the first freeze protection interval threshold is greater than the second freeze protection interval threshold.

4. The antifreeze control method of a heat pump module unit as set forth in claim 1, wherein: before receiving the signal for entering the anti-freezing mode, the method comprises

Acquiring the ambient temperature and the circulating water temperature;

judging whether the environmental temperature is less than or equal to an environmental temperature threshold value or not, and whether the circulating water temperature is less than or equal to a first circulating water anti-freezing temperature threshold value or not;

and if the judgment results are yes, sending the signal for entering the anti-freezing mode.

5. The antifreeze control method of a heat pump module group according to any one of claims 1 to 4, wherein: the different levels of the anti-freezing operation modes are adopted according to different circulating water temperatures and comprise

Judging whether the temperature of the circulating water is less than or equal to a first circulating water anti-freezing temperature threshold value or not, and if so, controlling the compressor to start;

judging whether the temperature of the circulating water is greater than a first circulating water anti-freezing temperature threshold value and less than or equal to a second circulating water anti-freezing temperature threshold value, and if so, controlling an auxiliary heating unit to start;

judging whether the temperature of the circulating water is greater than a second circulating water anti-freezing temperature threshold value and less than or equal to a third circulating water anti-freezing temperature threshold value, and if so, controlling the circulating water pump to continuously operate;

and judging whether the temperature of the circulating water is greater than a third circulating water anti-freezing temperature threshold value or not, and if so, controlling the circulating water pump to stop running.

6. The antifreeze control method of heat pump module group according to claim 5, wherein:

and when the circulating water pump is controlled to continuously operate, judging whether the circulating water pump exits the anti-freezing mode after continuously operating for a second set time, and if not, controlling the compressor to start.

7. The antifreeze control method of a heat pump module group according to claim 5 or 6, wherein:

controlling the starting of the compressors comprises controlling the starting of a plurality of compressors in the heat pump module unit one by one;

preferably, whether the temperature rise of the circulating water temperature reaches the temperature rise standard is judged every third set time, if not, one compressor is added, and if yes, the currently started compressor is kept running.

8. The antifreeze control method of a heat pump module group according to any one of claims 5 to 7, wherein:

when the anti-freezing operation mode is compressor starting, judging whether the temperature of the circulating water exceeds a first circulating water anti-freezing temperature threshold value in real time, and if so, exiting the anti-freezing mode;

when the anti-freezing operation mode is that the heating unit is started, judging whether the temperature of the circulating water exceeds a second circulating water anti-freezing temperature threshold value or not in real time, and if so, exiting the anti-freezing mode;

and when the anti-freezing operation mode is that the circulating water pump continuously operates, judging whether the temperature of the circulating water exceeds a third circulating water anti-freezing temperature threshold value in real time, and if so, exiting the anti-freezing mode.

9. The antifreeze control method of a heat pump module unit as set forth in claim 8, wherein:

judging whether the operation mode of the heat pump module unit is a refrigeration mode before the stop of the circulating water pump;

if so, taking the first circulating water refrigeration de-freezing temperature as the first circulating water de-freezing temperature threshold, taking the second circulating water refrigeration de-freezing temperature as the second circulating water de-freezing temperature threshold, and taking the third circulating water refrigeration de-freezing temperature as the third circulating water de-freezing temperature threshold;

if not, the first circulating water non-refrigeration anti-freezing temperature threshold value is the first circulating water non-refrigeration anti-freezing temperature, the second circulating water non-refrigeration anti-freezing temperature threshold value is the second circulating water non-refrigeration anti-freezing temperature, and the third circulating water non-refrigeration anti-freezing temperature threshold value is the third circulating water non-refrigeration anti-freezing temperature;

the refrigeration de-freezing temperature of the first circulating water is less than the non-refrigeration de-freezing temperature of the first circulating water, the refrigeration de-freezing temperature of the second circulating water is less than the non-refrigeration de-freezing temperature of the second circulating water, and the refrigeration de-freezing temperature of the third circulating water is less than the non-refrigeration de-freezing temperature of the third circulating water.

10. A heat pump module unit characterized by employing the antifreeze control method as set forth in any one of claims 1 to 9.

Technical Field

The invention belongs to the technical field of heat pumps, and particularly relates to a heat pump module unit and an anti-freezing control method thereof.

Background

The air source heat pump unit is known by more and more people because of high heating and refrigerating performance coefficients, and with the more and more mature air source heat pump technology, the application range of the air source heat pump is expanded from the north of a Yangtze river basin to a yellow river basin, and because the winter temperature of the part of the area is lower, the possibility that a water side heat exchanger is frozen down exists under the condition that the heat pump is shut down in winter or does not work at night.

The more common solutions at present include: firstly, the water pump does not stop when running for a long time in winter. And secondly, the unit is in linkage control with the water pump, the water pump is controlled to operate after the unit detects the anti-freezing control requirement, and then the heat pump is started to operate if the water temperature continues to drop until the water temperature reaches an anti-freezing exit condition. Thirdly, a water pipeline or a heat exchanger is electrified for heating and other control methods.

However, these control methods have different drawbacks.

First, the water pump operates without stopping for long periods in the winter. The situation is suitable for occasions with heating demands both in the daytime and at night in winter, but the situation that only heating is needed in the daytime or the machine needs to be stopped for a long time can cause waste of energy.

And secondly, a unit and water pump linkage control scheme. The principle of the control scheme is that after the unit detects an anti-freezing control signal, a system circulating water pump is started to circulate water in a pipeline, and if the water temperature continues to drop, and meanwhile, the heat pump equipment detects that a water flow switch is in a closed state, the heat pump is forcibly started to operate or auxiliary electric heating output is controlled. It can be seen that the precondition for ensuring the effective anti-freezing effect is that firstly the circulating water pump of the system must be linked with the control system of the air source heat pump unit, that is, the automatic control of the water pump is completed by the heat pump unit. However, in an engineering field, most of circulating water pumps of the system are independent of the heat pump unit to operate independently due to reasons that the early engineering design is not smooth to link or the heat pump unit modules have more water pump control signals and the like, so that after the anti-freezing control request of the equipment occurs, the water pump of the system is not linked with the heat pump equipment, the water flow switch of the heat pump equipment is usually caused to alarm, and the equipment is stopped.

And the third scheme is that electric heating is added on a water pipeline or a heat exchanger of a heat pump unit, and the scheme has more applications in early heat pump system applications. However, with the popularization of air source heat pump units, the competition among manufacturers of heat pump equipment is more and more intense, and the cost control of each manufacturer on the respective equipment is more and more strict, so that unnecessary configurations such as electric heating and the like are generally cancelled. This antifreeze control measure cannot be realized.

In addition, in the second and third antifreeze control methods, the antifreeze mode is entered whenever the circulating water temperature is low, and a false alarm may occur.

In view of the above, the present invention is particularly proposed.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides an anti-freezing control method of a heat pump module unit.

Another object of the present invention is to provide a heat pump module unit for implementing the above-mentioned anti-freezing control method.

In order to solve the technical problems, the invention adopts the technical scheme that:

an antifreezing control method for heat pump module unit includes

Receiving a signal for entering an anti-freezing mode;

and controlling the circulating water pump to operate, acquiring the temperature of circulating water after a first set time, and adopting different levels of anti-freezing operation modes according to different temperatures of the circulating water.

Further, before receiving the signal for entering the anti-freeze mode, the method comprises

Acquiring the ambient temperature and the shutdown time of the circulating water pump;

judging whether the environmental temperature is less than or equal to an environmental temperature threshold value or not, and whether the shutdown time of the circulating water pump reaches an anti-freezing time interval threshold value or not;

and if the judgment results are yes, sending the signal for entering the anti-freezing mode.

Further, judging whether the environment temperature is greater than or equal to the anti-freezing interval ring temperature standard or not;

if so, taking a first anti-freezing time interval threshold as the anti-freezing time interval threshold;

if not, the second anti-freezing time interval threshold is taken as the anti-freezing time interval threshold;

the first freeze protection interval threshold is greater than the second freeze protection interval threshold.

It is also possible that before receiving the signal to enter the freeze protection mode, it comprises

Acquiring the ambient temperature and the circulating water temperature;

judging whether the environmental temperature is less than or equal to an environmental temperature threshold value or not, and whether the circulating water temperature is less than or equal to a first circulating water anti-freezing temperature threshold value or not;

and if the judgment results are yes, sending the signal for entering the anti-freezing mode.

Further, the different levels of the anti-freezing operation modes according to different circulating water temperatures comprise

Judging whether the temperature of the circulating water is less than or equal to a first circulating water anti-freezing temperature threshold value or not, and if so, controlling the compressor to start;

judging whether the temperature of the circulating water is greater than a first circulating water anti-freezing temperature threshold value and less than or equal to a second circulating water anti-freezing temperature threshold value, and if so, controlling an auxiliary heating unit to start;

judging whether the temperature of the circulating water is greater than a second circulating water anti-freezing temperature threshold value and less than or equal to a third circulating water anti-freezing temperature threshold value, and if so, controlling the circulating water pump to continuously operate;

and judging whether the temperature of the circulating water is greater than a third circulating water anti-freezing temperature threshold value or not, and if so, controlling the circulating water pump to stop running.

Further, when the circulating water pump is controlled to continuously operate, whether the circulating water pump exits the anti-freezing mode after continuously operating for a second set time is judged, and if not, the compressor is controlled to start.

Further, the step of controlling the starting of the compressors comprises controlling the starting of a plurality of compressors in the heat pump module unit one by one;

preferably, whether the temperature rise of the circulating water temperature reaches the temperature rise standard is judged every third set time, if not, one compressor is added, and if yes, the currently started compressor is kept running.

Further, when the anti-freezing operation mode is compressor starting, judging whether the temperature of the circulating water exceeds a first circulating water anti-freezing temperature threshold value in real time, and if so, exiting the anti-freezing mode;

when the anti-freezing operation mode is that the heating unit is started, judging whether the temperature of the circulating water exceeds a second circulating water anti-freezing temperature threshold value or not in real time, and if so, exiting the anti-freezing mode;

and when the anti-freezing operation mode is that the circulating water pump continuously operates, judging whether the temperature of the circulating water exceeds a third circulating water anti-freezing temperature threshold value in real time, and if so, exiting the anti-freezing mode.

Further, judging whether the operation mode of the heat pump module unit is a refrigeration mode before the circulating water pump is stopped;

if so, taking the first circulating water refrigeration de-freezing temperature as the first circulating water de-freezing temperature threshold, taking the second circulating water refrigeration de-freezing temperature as the second circulating water de-freezing temperature threshold, and taking the third circulating water refrigeration de-freezing temperature as the third circulating water de-freezing temperature threshold;

if not, the first circulating water non-refrigeration anti-freezing temperature threshold value is the first circulating water non-refrigeration anti-freezing temperature, the second circulating water non-refrigeration anti-freezing temperature threshold value is the second circulating water non-refrigeration anti-freezing temperature, and the third circulating water non-refrigeration anti-freezing temperature threshold value is the third circulating water non-refrigeration anti-freezing temperature;

the refrigeration de-freezing temperature of the first circulating water is less than the non-refrigeration de-freezing temperature of the first circulating water, the refrigeration de-freezing temperature of the second circulating water is less than the non-refrigeration de-freezing temperature of the second circulating water, and the refrigeration de-freezing temperature of the third circulating water is less than the non-refrigeration de-freezing temperature of the third circulating water.

A heat pump module unit adopts the anti-freezing control method.

After the technical scheme is adopted, compared with the prior art, the invention has the following beneficial effects.

1. According to the invention, before the actual anti-freezing operation mode is selected, the circulating water is firstly controlled to circulate for a period of time, so that the water in the heat pump module unit can flow, the detected circulating water temperature is relatively real, and the condition of false alarm caused by local low temperature at the position of a sensor arranged on a circulating water return pipe or a circulating water outlet pipe is avoided, so that the load of the heat pump module unit and the energy consumption load of a user caused by frequently starting the anti-freezing mode are avoided.

2. The invention determines the anti-freezing time interval according to the environment temperature, enters the anti-freezing operation modes of different levels according to the temperature of the circulating water, can greatly reduce the possibility that the heat pump module unit is frozen in a shutdown state in winter through triple anti-freezing, and provides a guarantee for the application of the heat pump in cold regions.

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention, are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention without limiting the invention to the right. It is obvious that the drawings in the following description are only some embodiments, and that for a person skilled in the art, other drawings can be derived from them without inventive effort. In the drawings:

FIG. 1 is a schematic flow chart diagram illustrating an embodiment of an antifreeze control method for a heat pump module unit according to the present invention;

fig. 2 is a schematic flow chart of another embodiment of the anti-freezing control method for the heat pump module unit.

It should be noted that the drawings and the description are not intended to limit the scope of the inventive concept in any way, but to illustrate it by a person skilled in the art with reference to specific embodiments.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and the following embodiments are used for illustrating the present invention and are not intended to limit the scope of the present invention.

In the description of the present invention, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred devices or elements must have specific orientations, be constructed in specific orientations, and be operated, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

As shown in fig. 1 and 2, the present invention provides a heat pump module unit and an anti-freeze control method thereof. The heat pump module unit comprises a plurality of compressors, and a circulating water return pipe and a circulating water outlet pipe are arranged between the compressors and the user side. And sensors for detecting the temperature of the circulating water are arranged on the circulating water return pipe and the circulating water outlet pipe. According to the invention, a low temperature is selected between the circulating return water temperature and the circulating outlet water temperature as the circulating water temperature for judging whether to enter the actual anti-freezing mode. When a sensor on the circulating water return pipe or the circulating water outlet pipe breaks down, the temperature detected by the sensor which can normally work is selected as the circulating water temperature.

Furthermore, an electric heating unit is arranged on the circulating water return pipe and/or the circulating water outlet pipe, and can heat water in the circulating water return pipe and/or the circulating water outlet pipe.

It is understood that the heat pump module unit of the present invention should further include a circulating water pump for driving the flow of the circulating water.

The invention discloses an anti-freezing control method of a heat pump module unit, which comprises the following steps:

receiving a signal for entering an anti-freezing mode;

and controlling the circulating water pump to operate, acquiring the temperature of circulating water after a first set time, and adopting different levels of anti-freezing operation modes according to different temperatures of the circulating water.

In the above scheme, when the control unit of the heat pump module unit receives a signal for entering the anti-freezing mode after logical operation, at this time, the circulating water pump is controlled to start operation, and after a first set time, for example, 60 seconds, the circulating water temperature is acquired, so that the anti-freezing operation mode corresponding to the circulating water temperature is selected according to the grade of the circulating water temperature, and the actual anti-freezing mode is entered.

According to the invention, before the actual anti-freezing operation mode is selected, the circulating water is firstly controlled to circulate for a period of time, so that the water in the heat pump module unit can flow, the detected circulating water temperature is relatively real, and the condition of false alarm caused by local low temperature at the position of a sensor arranged on a circulating water return pipe or a circulating water outlet pipe is avoided, so that the load of the heat pump module unit and the energy consumption load of a user caused by frequently starting the anti-freezing mode are avoided.

In some embodiments of the present invention, before receiving the signal to enter the anti-freeze mode, the method further comprises:

acquiring the ambient temperature and the shutdown time of the circulating water pump;

judging whether the environmental temperature is less than or equal to an environmental temperature threshold value or not, and whether the shutdown time of the circulating water pump reaches an anti-freezing time interval threshold value or not;

and if the judgment results are yes, sending the signal for entering the anti-freezing mode.

In detail, the control unit of the heat pump module unit judges whether to enter the anti-freezing mode based on the ambient temperature and the shutdown time of the circulating water pump.

Specifically, a sensor for detecting the ambient temperature is arranged on the heat pump module unit, the control unit is connected with the sensor, and the ambient temperature is obtained through the sensor. Meanwhile, the control unit is also electrically connected with the circulating water pump, so that the shutdown time of the circulating water pump can be acquired.

When the actual temperature of the user side reaches the set temperature for cooling or heating of the heat pump module unit, the user side enters a standby state, and at the moment, the circulating water pump, the compressor and the like enter the standby state. When the external environment is low, the water-side heat exchanger may be frozen when the heat pump module unit is in a standby state.

Therefore, after acquiring the environment temperature and the shutdown time of the circulating water pump, the control unit of the invention judges whether the environment temperature is less than or equal to the environment temperature threshold value and whether the shutdown time of the circulating water pump reaches the anti-freezing time interval threshold value, and if the judgment results are yes, the control unit sends the signal for entering the anti-freezing mode.

It will be appreciated that both the ambient temperature threshold and the freeze protection interval threshold are preset in the control unit.

In the scheme, the judgment parameter of the shutdown time of the circulating water pump is increased, because the temperature of the water inside the water side heat exchanger which is just in a standby state cannot be immediately reduced to the degree of freezing the water side heat exchanger, if only the judgment parameter of the environmental temperature is adopted, the heat pump module unit can be in an anti-freezing mode for a long time, great energy consumption burden can be caused to users, and energy conservation and emission reduction are not facilitated.

In a further scheme, the antifreezing time interval threshold value can also be selected according to different parameters of the environment temperature.

In detail, when the ambient temperature is greater than or equal to the antifreezing spacer ring temperature standard, the antifreezing time interval threshold is a first antifreezing time interval threshold.

And when the environment temperature is lower than the antifreezing spacer ring temperature standard, taking a second antifreezing time interval threshold as the antifreezing time interval threshold.

Preferably, the antifreezing interval ring temperature standard is 0 ℃.

The first freeze protection time interval threshold value can be selected within 50-70min, preferably 60 min.

The second freeze protection time interval threshold value may be selected within 20-40min, preferably 30 min.

In a special case, when a sensor detecting the ambient temperature fails, it is uniformly executed at the second freeze prevention time interval threshold.

In some other embodiments of the present invention, before receiving the signal to enter the anti-freeze mode, the method further includes:

acquiring the ambient temperature and the circulating water temperature;

judging whether the environmental temperature is less than or equal to an environmental temperature threshold value or not, and whether the circulating water temperature is less than or equal to a first circulating water anti-freezing temperature threshold value or not;

and if the judgment results are yes, sending the signal for entering the anti-freezing mode.

In the scheme, the environmental temperature and the circulating water temperature are used as judgment parameters for judging whether to send out a signal for entering the anti-freezing mode.

In some embodiments of the invention, different levels of anti-freezing operation modes are adopted according to different circulating water temperatures, and the anti-freezing operation modes comprise three different levels of anti-freezing operation modes, namely a water pump anti-freezing operation mode, an auxiliary heat anti-freezing operation mode and a press anti-freezing operation mode. Similarly, the three different levels of antifreeze modes of operation also include three different levels of antifreeze mode criteria.

Specifically, after the control unit obtains the temperature of the circulating water, whether the temperature of the circulating water is smaller than or equal to a first circulating water anti-freezing temperature threshold value is judged, if yes, the compressor is controlled to start, and the mode is the press anti-freezing operation mode.

In detail, the step of controlling the starting of the compressor comprises controlling the starting of a plurality of compressors in the heat pump module unit one by one.

Preferably, whether the temperature rise of the circulating water temperature reaches the temperature rise standard is judged every third set time, if not, one compressor is added, and if yes, the currently started compressor is kept running.

For example, if the temperature rise of the circulating water temperature is less than 1 ℃ every 8min, one compressor is loaded until all the compressors in the heat pump module unit are loaded.

And if the circulating water temperature is higher than the first circulating water anti-freezing temperature threshold value, judging whether the circulating water temperature is lower than or equal to a second circulating water anti-freezing temperature threshold value, and if so, controlling an auxiliary heating unit to start, which is an auxiliary heating anti-freezing operation mode.

In detail, the auxiliary heating unit may be an electric heater. The electric heater is started, a water flow switch needs to be detected, and the auxiliary electric heating is started to prevent freezing when the conditions are met.

And if the temperature of the circulating water is greater than the second circulating water anti-freezing temperature threshold value, judging whether the temperature of the circulating water is less than or equal to a third circulating water anti-freezing temperature threshold value, and if so, controlling the circulating water pump to continuously operate, namely a water pump anti-freezing operation mode.

In detail, when the temperature of the circulating water is between the second circulating water anti-freezing temperature threshold and the third circulating water anti-freezing temperature threshold, the circulating water pump is controlled to start to operate before entering the anti-freezing operation modes of different levels, and the circulating water pump is controlled to continuously operate at the moment, so that the water in the water side heat exchanger and the circulating water return pipe or the circulating water outlet pipe is prevented from being frozen due to over-low local temperature caused by non-circulation.

Further, when the circulating water pump is controlled to continuously operate, whether the circulating water pump exits the anti-freezing mode after continuously operating for a second set time is judged, and if not, the compressor is controlled to start.

In detail, when the anti-freezing mode of the heat pump module unit is in the water pump anti-freezing operation mode, if the standard of exiting the anti-freezing mode is not met after the circulating water pump operates for a period of time, the anti-freezing effect of the water pump anti-freezing operation mode is very small, and therefore the compressor anti-freezing operation mode is entered.

Specifically, the second setting time can be selected within 15-35min, and preferably, the second setting time is 20 min.

And if the temperature of the circulating water is greater than the third circulating water anti-freezing temperature threshold value, controlling the circulating water pump to stop running and waiting for entering an anti-freezing mode next time.

In the scheme, the anti-freezing time interval is determined according to the environment temperature, the anti-freezing operation modes of different levels are entered according to the temperature of the circulating water, the possibility that the heat pump module unit is frozen in a winter shutdown state can be greatly reduced through triple anti-freezing, and the application of the heat pump module unit in cold regions is guaranteed.

For some special conditions which may occur in the heat pump module unit, the invention carries out anti-freezing according to the following conditions:

A. and selecting a low temperature between the circulating return water temperature and the circulating outlet water temperature as the circulating water temperature, and selecting another temperature capable of working normally as the circulating water temperature when one of the circulating return water temperature and the circulating outlet water temperature cannot be obtained.

B. When the environmental temperature cannot be obtained, no environmental temperature limiting condition exists, as long as the shutdown time of the circulating water pump exceeds a second anti-freezing time interval threshold value or the circulating water temperature is less than or equal to a first circulating water anti-freezing temperature threshold value, the circulating water pump is started to operate for 60 seconds, the circulating water temperature is detected, and then anti-freezing operation modes of different levels are adopted according to the circulating water temperature.

C. When the circulating return water temperature and the circulating outlet water temperature cannot be obtained, the anti-freezing operation mode only selects the water pump anti-freezing operation mode, namely, the compressor is not started and the electric heating action is not performed, wherein the starting and the stopping of the circulating water pump are determined according to the ambient temperature.

D. When the circulating return water temperature, the circulating outlet water temperature and the environment temperature cannot be obtained, the circulating water pump is operated as long as the shutdown time of the circulating water pump is greater than or equal to the second anti-freezing time interval threshold value.

E. When the water flow switch fails or the circulating water pump fails and cannot be started, the highest frequency of the anti-freezing operation of the compressor cannot exceed 60 Hz.

F. When the fan cannot be operated due to a fault, the maximum frequency of the anti-freeze operation of the compressor cannot exceed 44 Hz.

G. When the circulating water pump fails and cannot be started, the water pump is not allowed to be prevented from being frozen, and freezing can be performed only by starting the compressor in the module needing freezing prevention.

Further, the water pump anti-freezing operation mode, the auxiliary heating anti-freezing operation mode and the press anti-freezing operation mode comprise three different levels of anti-freezing mode standards:

and when the anti-freezing operation mode is the press anti-freezing operation mode, judging whether the temperature of the circulating water exceeds a first circulating water anti-freezing temperature withdrawal threshold value in real time, and if so, exiting the anti-freezing mode.

And when the anti-freezing operation mode is the auxiliary heating anti-freezing operation mode, judging whether the temperature of the circulating water exceeds a second circulating water anti-freezing temperature threshold value in real time, and if so, exiting the anti-freezing mode.

And when the anti-freezing operation mode is the water pump anti-freezing operation mode, judging whether the temperature of the circulating water exceeds a third circulating water anti-freezing temperature threshold value in real time, and if so, exiting the anti-freezing mode.

In the preferred scheme, whether the operation mode of the heat pump module unit is a refrigeration mode before the circulating water pump is stopped is judged; if the operation mode of the heat pump module unit is a refrigeration mode before the circulating water pump is stopped, the first circulating water refrigeration anti-freezing temperature threshold value is the first circulating water refrigeration anti-freezing temperature, the second circulating water refrigeration anti-freezing temperature threshold value is the second circulating water refrigeration anti-freezing temperature, and the third circulating water refrigeration anti-freezing temperature threshold value is the third circulating water refrigeration anti-freezing temperature. If the operation mode of the heat pump module unit before the stop of the circulating water pump is a heating mode or other modes, the first circulating water non-refrigeration anti-freezing temperature threshold value is the first circulating water non-refrigeration anti-freezing temperature, the second circulating water non-refrigeration anti-freezing temperature threshold value is the second circulating water non-refrigeration anti-freezing temperature, and the third circulating water non-refrigeration anti-freezing temperature threshold value is the third circulating water non-refrigeration anti-freezing temperature.

The refrigeration and antifreeze temperature of the first circulating water is lower than the non-refrigeration and antifreeze temperature of the first circulating water, the refrigeration and antifreeze temperature of the second circulating water is lower than the non-refrigeration and antifreeze temperature of the second circulating water, and the refrigeration and antifreeze temperature of the third circulating water is lower than the non-refrigeration and antifreeze temperature of the third circulating water.

It is noted that when the freeze protection mode is exited, the circulating water pump is stopped after all the compressor/electric heating units have been stopped for 60 seconds.

The compressor stops and reports faults when high-pressure protection, exhaust temperature overhigh protection, driving compressor faults and the like occur, other faults or protections do not affect entering of the anti-freezing operation mode of the compressor, and when faults occur in the operation process of the anti-freezing mode, the heat pump module unit is processed according to the anti-freezing mode.

In the preferred scheme, when the environmental temperature is greater than the sum of the environmental temperature threshold and the temperature difference of the anti-freezing environment, the circulating water temperature is not detected, and the anti-freezing mode is directly exited.

And when the environmental temperature is less than or equal to the sum of the environmental temperature threshold and the temperature difference of the anti-freezing environment, or the environmental temperature cannot be obtained, exiting the anti-freezing mode according to the rule.

As shown in fig. 1, the anti-freezing control method of the heat pump module unit specifically includes the following steps:

s100, acquiring the ambient temperature and the shutdown time of the circulating water pump;

s101, judging whether the environment temperature is less than or equal to an environment temperature threshold value or not, judging whether the shutdown time of the circulating water pump reaches an anti-freezing time interval threshold value or not, and if yes, entering S102; if not, standby;

s102, controlling a circulating water pump to operate, acquiring the temperature of circulating water after a first set time, judging whether the temperature of the circulating water is less than or equal to a first circulating water anti-freezing temperature threshold value, if so, entering a step S103, and if not, entering a step S104;

s103, adopting a press anti-freezing operation mode;

s104, judging whether the temperature of the circulating water is greater than a first circulating water anti-freezing temperature threshold value and less than or equal to a second circulating water anti-freezing temperature threshold value, if so, entering S105, and if not, entering S106;

s105, adopting an auxiliary heating anti-freezing operation mode;

s106, judging whether the temperature of the circulating water is greater than a second circulating water anti-freezing temperature threshold value and less than or equal to a third circulating water anti-freezing temperature threshold value, if so, entering a step S107; if not, go to step S108;

s107, adopting a water pump anti-freezing operation mode;

and S108, judging whether the temperature of the circulating water is greater than a third circulating water anti-freezing temperature threshold value, and if so, controlling the circulating water pump to stop running.

Or, as shown in fig. 2, the anti-freezing control method of the heat pump module unit specifically includes the following steps:

s200, acquiring the ambient temperature and the circulating water temperature;

s201, judging whether the environment temperature is less than or equal to an environment temperature threshold value or not, and whether the circulating water temperature is less than or equal to a first circulating water anti-freezing temperature threshold value or not, and if yes, entering S202; if not, standby;

s202, controlling a circulating water pump to operate, acquiring the temperature of circulating water after a first set time, judging whether the temperature of the circulating water is less than or equal to a first circulating water anti-freezing temperature threshold value, if so, entering a step S203, and if not, entering a step S204;

s203, adopting a press anti-freezing operation mode;

s204, judging whether the temperature of the circulating water is greater than a first circulating water anti-freezing temperature threshold value and less than or equal to a second circulating water anti-freezing temperature threshold value, if so, entering S205, and if not, entering S206;

s205, adopting an auxiliary heating anti-freezing operation mode;

s206, judging whether the temperature of the circulating water is greater than a second circulating water anti-freezing temperature threshold value and less than or equal to a third circulating water anti-freezing temperature threshold value, if so, entering a step S207; if not, go to step S208;

s207, adopting a water pump anti-freezing operation mode;

and S208, judging whether the temperature of the circulating water is greater than a third circulating water anti-freezing temperature threshold value, and if so, controlling the circulating water pump to stop running.

For each of the above parameters of the present invention, the ranges and preferred values thereof can be referred to table 1.

TABLE 1 value ranges and preferred values for the respective parameters

Type of parameter	Value range	Preferred numerical values
			First set time	40～80s	60s
The second set time	15～35min	20min
			The third setting time	6～10min	8min
Ambient temperature threshold	1～3℃	2℃
			Standard of anti-freezing spacer ring temperature	-1～1℃	0℃
First freeze interval threshold	50-70min	60min
			Second freeze protection interval threshold	20-40min	30min
First circulating water antifreezing temperature threshold	2～5℃	3℃
			Second circulating water anti-freezing temperature threshold	3～6℃	4℃
Third circulating water anti-freezing temperature threshold	4～6℃	5℃
			First circulating water refrigeration anti-freezing temperature	5～9℃	7℃
Second circulating water refrigeration anti-freezing temperature	6～10℃	6℃
			Third circulating water refrigeration anti-freezing temperature	6～10℃	6℃
First circulating water uncooled anti-freezing temperature	12～18℃	15℃
			Non-refrigeration anti-freezing temperature of second circulating water	8～12℃	10℃
Third circulating water non-refrigeration anti-freezing temperature	6～10℃	8℃

Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.