CN110793239B - Large-scale air source heat pump frosting judgment and online defrosting system and method - Google Patents
Large-scale air source heat pump frosting judgment and online defrosting system and method Download PDFInfo
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- CN110793239B CN110793239B CN201910956354.6A CN201910956354A CN110793239B CN 110793239 B CN110793239 B CN 110793239B CN 201910956354 A CN201910956354 A CN 201910956354A CN 110793239 B CN110793239 B CN 110793239B
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B30/00—Heat pumps
- F25B30/06—Heat pumps characterised by the source of low potential heat
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B47/00—Arrangements for preventing or removing deposits or corrosion, not provided for in another subclass
- F25B47/02—Defrosting cycles
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B49/00—Arrangement or mounting of control or safety devices
- F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B2347/00—Details for preventing or removing deposits or corrosion
- F25B2347/02—Details of defrosting cycles
- F25B2347/023—Set point defrosting
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Abstract
The invention discloses a frosting judgment and online defrosting system and a method thereof for a large-scale air source heat pump, belonging to the technical field of heat pump systems, wherein the control method comprises a step of frosting degree judgment and a step of starting online defrosting operation; the frosting degree of the ambient air heat exchanger and whether defrosting operation is carried out or not are judged by measuring the air temperature entering and exiting the ambient air heat exchanger and the temperature of the antifreeze solution entering and exiting the ambient air heat exchanger and calculating the temperature difference between the temperature difference and the temperature difference set by the system; when defrosting, the antifreeze enters the ambient air heat exchanger by direct heating, and the hot antifreeze flows through the ambient air heat exchanger to melt the frost condensed by the heat exchanger, so that online defrosting of the system is realized.
Description
Technical Field
The invention belongs to the technical field of heat pump systems, relates to an air source heat pump system, and particularly relates to a large-scale air source heat pump frosting judgment and online defrosting system and a method thereof.
Background
The air source heat pump unit is also called as an air-cooled heat pump unit and is a general name of an air-air heat pump and an air-water heat pump. The method is characterized by comprising the following steps: the machine has two purposes, and has double functions of cooling in summer and heating in winter; the environmental energy is taken from air in natural environment, and the energy source limiting factor is less; the installation is convenient, and the building top layer or the outdoor open field is placed in the open air; the one-time investment is low. And thus is widely used.
The traditional air source system is easy to generate the frosting phenomenon, after frosting, the compressor is usually adopted to work and change the direction, the evaporator is changed into a condenser, and the refrigerant is condensed to release heat to finish defrosting. The system consumes long time to complete one-time switching, has long balance time for work recovery after one-time switching, has high energy consumption and seriously influences normal heat supply.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a large-scale air source heat pump frost formation judgment and online defrosting system and a method thereof, which fully utilize the condition that antifreeze flows inside an ambient air heat exchanger tube, the antifreeze is heated to melt the frost on the interface of a heat exchange tube, namely, the frost is melted from inside to outside, the interface of the heat exchange tube only melts a small amount of frost to enable the condensed frost to directly slide freely with the tube wall, the frost with a loose structure starts to naturally peel off, the heat energy consumed by defrosting is far lower than the heat energy required for melting all the frost, and the online defrosting can be realized under the condition that the system is not stopped and does not run reversely.
In order to solve the technical problems, the invention adopts the technical scheme that:
the invention provides a large-scale air source heat pump frosting judgment and online defrosting system which comprises an ambient air heat exchanger module, a heat pump unit module, a user energy supply side module, an online monitoring system, a defrosting device and a control computer.
Further, the ambient air heat exchanger module comprises an ambient air heat exchanger, an antifreeze expansion water tank and an industrial fan, wherein the antifreeze expansion water tank is connected with the ambient air heat exchanger; the defrosting device is a resistance heater, is arranged on a path of the antifreeze medium flowing into the ambient air heat exchanger, and is connected with the control computer.
Furthermore, the online monitoring system comprises an air temperature online testing system for monitoring the air temperature of the air heat exchanger in the inlet and outlet environment in real time and an antifreeze temperature online testing system for monitoring the antifreeze temperature of the air heat exchanger in the inlet and outlet environment in real time, wherein the air temperature online testing system and the antifreeze temperature online testing system are both connected with the control computer and transmit data acquired in real time to the control computer.
Furthermore, the heat pump unit module comprises an evaporator, an antifreeze heat exchange circulating system, a compressor unit, an expansion valve, a condenser and a water heat exchange circulating system, the user energy supply side module comprises a buffer water tank and a user heat supply water pump, the evaporator is connected with the antifreeze expansion water tank through the antifreeze heat exchange circulating system, and the condenser is connected with the buffer water tank through the water heat exchange circulating system; the compressor unit is composed of a plurality of compressors, the evaporators and the compressors are in a one-to-many relationship, low-temperature anti-freezing liquid generated by the evaporators is input into the ambient air heat exchanger module, the low-temperature anti-freezing liquid absorbs heat energy from the environment and is heated, then the high-temperature anti-freezing liquid returns to the evaporators, the condensers and the compressors are in a one-to-many relationship, high-temperature hot water generated by the condensers is input into the user energy supply side module, and the low-temperature hot water returns to the condensers after the high-temperature hot water releases heat energy to users and is cooled.
Furthermore, an antifreeze circulating pump is arranged on the antifreeze heat exchange circulating system, and a heat source circulating water pump is arranged on the water heat exchange circulating system.
The invention also provides a frost formation judgment and online defrosting method of the large-scale air source heat pump, which is carried out by the system and comprises the following steps:
judging the frosting degree;
and a step of starting an on-line defrosting operation.
Further, the frosting degree judgment method comprises the following specific steps:
on the premise of not influencing the air circulation passing through the ambient air heat exchanger, the surface of the ambient air heat exchanger is slightly frosted and does not influence the system operation, but the occurrence of a frost layer on the surface of the heat exchanger increases the thermal resistance between the antifreeze at the inner side of the heat exchanger and the air at the outer side of the heat exchanger, namely the temperature difference between the antifreeze and the air at the outer side of the heat exchanger is increased, the temperature difference is larger when the thickness of the frost layer is thicker, and the thickness of the frost layer on the surface is serious until the defrosting system can normally operate when the temperature difference reaches a certain degree, so that a certain quantitative relation exists between the temperature difference and the frosting degree.
By monitoring the temperature T of the inlet dry bulb of the ambient air heat exchanger in real timef1Outlet dry bulb temperature Tf2Ambient wet bulb temperature Tw1And the outlet wind speed V of the ambient air heat exchangerf(ii) a Simultaneously, the temperature T of the antifreezing heat exchange medium entering and exiting the evaporator is monitored on line in real timey1、Ty2Antifreezing heat exchange mediumMass flow rate Vy；
Calculating the average temperature of air at the inlet and the outlet of the ambient air heat exchanger: t isfp＝(Tf1+Tf2)/2
Calculating the average temperature of an inlet and an outlet of an anti-freezing heat exchange medium of the evaporator: t isyp＝(Ty1+Ty2)/2
Calculating the difference between the average temperature of the air at the inlet and the outlet of the ambient air heat exchanger and the average temperature of the anti-freezing heat exchange medium at the inlet and the outlet of the evaporator: delta Tfyp＝Tfp-Typ；
System basis Tf1、Tf2、Tw1、Vf；Ty1、Ty2、VySetting DeltaTfypBased on the measured Tf1、Tf2、Tw1、Vf；Ty1、Ty2、VyCorresponding delta T in real time in the databasefypIf Δ T is actually measuredfypAnd if the temperature is higher than the set value, starting a defrosting working procedure.
Further, after the defrosting operation is started, the circulation flow of the anti-freezing solution is firstly reduced to about 5% of the normal flow, the resistance heater is started to heat the flowing anti-freezing solution, the temperature is controlled to be above 5 ℃ after the heating, the hot anti-freezing solution flows into the ambient air heat exchanger tube, the frost ablation occurs on the interface of the tube wall, the frost layer condensed on the tube wall is naturally peeled off, the temperature of the anti-freezing solution flowing out of the ambient air heat exchanger reaches 0 ℃, and then the defrosting operation is finished.
And further, after the defrosting operation is finished, firstly, stopping heating of the resistance heater, recovering the circulation flow of the antifreeze solution, and recovering the normal operation of the system.
Compared with the prior art, the invention has the advantages that:
(1) the frosting degree of the ambient air heat exchanger and whether defrosting operation is carried out or not are judged by measuring the air temperature entering and exiting the ambient air heat exchanger and the temperature of the antifreeze solution entering and exiting the ambient air heat exchanger and calculating the temperature difference between the temperature difference and the temperature difference set by the system;
(2) the invention fully utilizes the condition that the antifreeze flows inside a tube of an ambient air heat exchanger, a resistance heater is arranged on the path of antifreeze medium flowing into the ambient air heat exchanger, the resistance heater is used for heating the antifreeze when defrosting, the antifreeze enters the ambient air heat exchanger by direct heating, firstly, the frost on the interface of the heat exchange tube is melted, namely, the frost is melted from inside to outside, as long as a small amount of frost is melted on the interface of the heat exchange tube, the condensed frost directly slides freely with the tube wall, the frost with loose structure starts to naturally peel off, and the heat energy consumed by defrosting is far lower than the heat energy required for melting all the frost.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a schematic diagram of the system structure of the present invention (the online monitoring system and the control computer are not shown in the figure);
FIG. 2 is a schematic diagram of the frosting decision and online defrosting method of the present invention.
In the figure, 1. ambient air heat exchanger; 2. an antifreeze expansion water tank; 3. an antifreeze circulating pump; 4. an evaporator; 5. a compressor; 6. an expansion valve; 7. a condenser; 8. a heat source circulating water pump; 9. a user hot water supply pump; 10. a buffer water tank; 11. an industrial fan; 12. a resistance heater.
Detailed Description
The invention is further described with reference to the following figures and specific embodiments.
As shown in fig. 1, the large-scale air source heat pump frosting judgment and online defrosting system comprises an ambient air heat exchanger module, a heat pump unit module, a user energy supply side module, an online monitoring system, a defrosting device and a control computer, wherein the ambient air heat exchanger module indirectly exchanges heat with the heat pump unit module through an antifreeze medium, the user energy supply side module indirectly exchanges heat with the heat pump unit module through water, and the defrosting device is installed on a path of the antifreeze medium flowing into the ambient air heat exchanger module.
The structure of each module is described in further detail as follows:
the environment air heat exchanger module comprises an environment air heat exchanger 1, an antifreeze expansion water tank 2 and an industrial fan 11, wherein the antifreeze expansion water tank 2 is connected with the environment air heat exchanger 1. The defrosting device is a resistance heater 12, is arranged on a path of the antifreeze medium flowing into the ambient air heat exchanger 1, and is connected with a control computer.
The heat pump unit module comprises an evaporator 4, an antifreeze heat exchange circulating system, a compressor unit, an expansion valve 6, a condenser 7 and a water heat exchange circulating system, wherein an antifreeze circulating pump 3 is arranged on the antifreeze heat exchange circulating system, and a heat source circulating water pump 8 is arranged on the water heat exchange circulating system.
The evaporator 4 is connected with the antifreeze expansion water tank 2 through an antifreeze heat exchange circulating system, and the condenser 7 is connected with the buffer water tank 10 through a water heat exchange circulating system. The compressor unit includes a plurality of compressors 5, and this embodiment will be described by exemplifying a configuration in which 4 compressors 5 are connected in parallel. The evaporator 4 and the compressor 5 are in a one-to-many relationship, the low-temperature antifreeze generated by the evaporator 4 is input into the ambient air heat exchanger module, the low-temperature antifreeze absorbs heat energy from the environment and returns to the evaporator 4 after being heated, the condenser 7 and the compressor 5 are in a one-to-many relationship, the high-temperature hot water generated by the condenser 7 is input into the user energy supply side module, and the high-temperature hot water releases heat energy to a user and returns to the condenser 7 after being cooled.
And the user energy supply side module comprises a buffer water tank 10 and a user hot water supply pump 9.
The online monitoring system comprises an air temperature online testing system for monitoring the air temperature of the in-and-out ambient air heat exchanger 1 in real time and an antifreeze temperature online testing system for monitoring the antifreeze temperature of the in-and-out ambient air heat exchanger 1 in real time, wherein the air temperature online testing system and the antifreeze temperature online testing system are both connected with the control computer and transmit data acquired in real time to the control computer. The air temperature online test system can be a temperature sensor f1 arranged at an air inlet of the ambient air heat exchanger 1 and a temperature sensor f2 arranged at an air outlet of the ambient air heat exchanger 1, and the antifreeze temperature online test system can be temperature sensors y1 and y2 arranged on a path of antifreeze entering and exiting the ambient air heat exchanger 1, namely, on an outlet and an inlet position of an antifreeze heat exchange medium of the evaporator. The system also comprises a sensor W1 for monitoring the temperature of the environmental wet bulb, an air speed sensor f arranged at the outlet of the environmental air heat exchanger 1 and a flow meter y arranged on the antifreeze liquid heat exchange circulating system.
In actual design, the ambient air heat exchanger 1 is single, or multiple in parallel, or multiple in series, and this embodiment and fig. 1 exemplify a single unit. Meanwhile, the ambient air heat exchanger 1 can be freely matched with the heat pump unit module according to requirements, and can be one-to-one, or realize one-to-many or many-to-one in a series or parallel mode. The ambient air heat exchanger 1 and the heat pump unit module shown in this embodiment and fig. 1 are matched in a one-to-one manner, and 4 compressors 5 in the heat pump unit module are provided in parallel as an example.
According to the invention, the ambient air heat exchanger module is adopted to indirectly exchange heat with the heat pump unit module through an antifreeze medium, the heat exchange mode is changed from a double-high heat exchange mode to a double-low heat exchange mode (low temperature difference heat exchange of air at the inlet and the outlet of the ambient air heat exchanger and low temperature difference heat exchange of the wall surface of the ambient air heat exchanger), the system does not frost under normal conditions, but if the system is in a low-temperature and high-humidity climate condition for a long time, such as a low-temperature and heavy-fog climate, and is continued for a long time, the air source heat pump in the double-low heat exchange mode can also generate a frosting phenomenon.
Under the low-temperature and high-humidity climatic conditions, if the temperature of the outlet air passing through the ambient air heat exchanger is lower than the dew point temperature of the inlet air, the outlet air generates condensation; if the wall temperature of the heat exchanger is lower than 0 ℃, the frosting phenomenon is easily generated on the tube wall, the heat exchange capacity of the heat exchanger is reduced after the frosting phenomenon occurs, in order to meet the requirement of ensuring the heat exchange quantity of the system, the system automatically controls and automatically adjusts the operation parameters to enlarge the difference between the ambient air temperature and the anti-freezing temperature, the heat exchange capacity between the media is improved by improving the temperature difference of the heat exchange media, namely, the temperature of the anti-freezing solution entering the ambient air heat exchanger is finally reduced, the wall temperature of the heat exchanger is further reduced, the frosting phenomenon is further aggravated, and the difference between the ambient air temperature and the anti-freezing temperature is enlarged.
And setting the temperature difference between the allowable ambient air temperature and the antifreeze liquid temperature under different environmental conditions according to the theoretical calculation result and the actual operation data of the frosting phenomenon under different ambient air temperatures, wherein if the actual test result is greater than the set value, the frosting phenomenon on the surface of the heat exchanger is considered to exceed the allowable range, and the defrosting operation can be started.
The method for determining frosting and online defrosting of a large-scale air source heat pump according to the present embodiment will be described with reference to fig. 1 and 2, in which the frosting degree and the defrosting operation of an ambient air heat exchanger are determined by measuring the temperature of air entering and exiting the ambient air heat exchanger and the temperature of antifreeze entering and exiting the ambient air heat exchanger, calculating the temperature difference between the two temperatures and comparing the temperature difference with the temperature difference set by the system. And if the measured temperature difference is larger than the set temperature difference, starting the defrosting operation by the system.
That is, the method for determining frosting and online defrosting of the large-scale air source heat pump mainly comprises the following steps:
judging the frosting degree;
and a step of starting an on-line defrosting operation.
The frosting degree judgment method comprises the following specific steps of:
real-time monitoring of ambient air heat exchanger inlet dry bulb temperature T through air temperature online testing systemf1Outlet dry bulb temperature Tf2Ambient wet bulb temperature Tw1And the outlet wind speed V of the ambient air heat exchangerf(ii) a Meanwhile, the temperature T of the antifreezing heat exchange medium entering and exiting the evaporator is monitored in real time on line through an antifreezing solution temperature online test systemy1、Ty2Flow V of antifreezing heat exchange mediumy。
Calculating the average temperature of air at the inlet and the outlet of the ambient air heat exchanger: t isfp＝(Tf1+Tf2)/2
Calculating the average temperature of an inlet and an outlet of an anti-freezing heat exchange medium of the evaporator: t isyp＝(Ty1+Ty2)/2
Calculating the difference between the average temperature of the air at the inlet and the outlet of the ambient air heat exchanger and the average temperature of the anti-freezing heat exchange medium at the inlet and the outlet of the evaporator: delta Tfyp＝Tfp-Typ；
System basis Tf1、Tf2、Tw1、Vf；Ty1、Ty2、VySetting DeltaTfypBased on the measured Tf1、Tf2、Tw1、Vf；Ty1、Ty2、VyCorresponding delta T in real time in the databasefypIf Δ T is actually measuredfypAnd if the temperature is higher than the set value, starting a defrosting working procedure.
After the defrosting operation is started, firstly, the circulation flow of the anti-freezing solution is reduced to about 5% of the normal flow, the resistance heater is started to heat the flowing anti-freezing solution, the temperature is controlled to be above 5 ℃ after the heating, the hot anti-freezing solution flows into the ambient air heat exchanger tube, the frost ablation occurs on the interface of the tube wall, the frost layer condensed on the tube wall is naturally peeled off, the temperature of the anti-freezing solution flowing out of the ambient air heat exchanger reaches 0 ℃, and then the defrosting operation is finished.
And (4) after the defrosting operation is finished, stopping heating of the resistance heater, recovering the circulation flow of the anti-freezing solution, and recovering the normal operation of the system.
In conclusion, the frosting degree of the ambient air heat exchanger and whether the defrosting operation is carried out are judged by measuring the air temperature entering and exiting the ambient air heat exchanger and the temperature of the antifreeze solution entering and exiting the ambient air heat exchanger, calculating the temperature difference between the air temperature entering and exiting the ambient air heat exchanger and the temperature difference set by the system, and comparing the temperature difference with the temperature difference set by the system; when defrosting, the antifreeze enters the ambient air heat exchanger by direct heating, and the hot antifreeze flows through the ambient air heat exchanger to melt the frost condensed by the heat exchanger, so that online defrosting of the system is realized.
It is understood that the above description is not intended to limit the present invention, and the present invention is not limited to the above examples, and those skilled in the art should understand that they can make various changes, modifications, additions and substitutions within the spirit and scope of the present invention.
Claims (6)
1. The large-scale air source heat pump frosting judgment and online defrosting system is characterized by comprising an ambient air heat exchanger module, a heat pump unit module, a user energy supply side module, an online monitoring system, a defrosting device and a control computer, wherein the ambient air heat exchanger module indirectly exchanges heat with the heat pump unit module through an antifreeze medium, the user energy supply side module indirectly exchanges heat with the heat pump unit module through water, and the defrosting device is arranged on a path of the antifreeze medium flowing into the ambient air heat exchanger module;
the environment air heat exchanger module comprises an environment air heat exchanger, an antifreeze expansion water tank and an industrial fan, wherein the antifreeze expansion water tank is connected with the environment air heat exchanger; the defrosting device is a resistance heater, is arranged on a path of the antifreeze medium flowing into the ambient air heat exchanger, and is connected with the control computer;
the online monitoring system comprises an air temperature online testing system for monitoring the air temperature of the air heat exchanger in and out of the environment in real time and an antifreeze temperature online testing system for monitoring the temperature of antifreeze in and out of the air heat exchanger in and out of the environment in real time, and the air temperature online testing system and the antifreeze temperature online testing system are both connected with the control computer and transmit data acquired in real time to the control computer;
the heat pump unit module comprises an evaporator, an antifreeze heat exchange circulating system, a compressor unit, an expansion valve, a condenser and a water heat exchange circulating system, the user energy supply side module comprises a buffer water tank and a user heat supply water pump, the evaporator is connected with the antifreeze expansion water tank through the antifreeze heat exchange circulating system, and the condenser is connected with the buffer water tank through the water heat exchange circulating system; the compressor unit is composed of a plurality of compressors, the evaporators and the compressors are in a one-to-many relationship, low-temperature anti-freezing liquid generated by the evaporators is input into the ambient air heat exchanger module, the low-temperature anti-freezing liquid absorbs heat energy from the environment and is heated, then the high-temperature anti-freezing liquid returns to the evaporators, the condensers and the compressors are in a one-to-many relationship, high-temperature hot water generated by the condensers is input into the user energy supply side module, and the low-temperature hot water returns to the condensers after the high-temperature hot water releases heat energy to users and is cooled.
2. The large-scale air source heat pump frost judgment and online defrosting system according to claim 1, wherein an antifreeze circulating pump is provided on the antifreeze heat exchange circulating system, and a heat source circulating water pump is provided on the water heat exchange circulating system.
3. The method for judging frosting and online defrosting of the large-scale air source heat pump is characterized by being carried out by using the antifreeze heat exchange circulating system and the water heat exchange circulating system of claim 2, and comprises the following steps: judging the frosting degree; and a step of starting an on-line defrosting operation.
4. The frost formation determination and online defrosting method for an enlarged air source heat pump according to claim 3, wherein the frost formation degree determination includes the following specific steps:
real-time monitoring ambient air heat exchanger inlet dry bulb temperature Tf1Outlet dry bulb temperature Tf2Ambient wet bulb temperature Tw1And the outlet wind speed V of the ambient air heat exchangerf(ii) a Simultaneously, the temperature T of the antifreezing heat exchange medium entering and exiting the evaporator is monitored on line in real timey1、Ty2Flow V of antifreezing heat exchange mediumy；
Calculating the average temperature of air at the inlet and the outlet of the ambient air heat exchanger: t isfp=（Tf1 +Tf2）/2
Calculating the average temperature of an inlet and an outlet of an anti-freezing heat exchange medium of the evaporator: t isyp=（Ty1 +Ty2）/2
Calculating the difference between the average temperature of the air at the inlet and the outlet of the ambient air heat exchanger and the average temperature of the anti-freezing heat exchange medium at the inlet and the outlet of the evaporator: delta Tfyp =Tfp-Typ；
System basis Tf1、Tf2、Tw1、Vf；Ty1、Ty2、VySetting DeltaTfypBased on the measured Tf1、Tf2、Tw1、Vf；Ty1、Ty2、VyCorresponding delta T in real time in the databasefypIf Δ T is actually measuredfypAnd if the temperature is higher than the set value, starting a defrosting working procedure.
5. The method for determining frosting and online defrosting of an upsized air source heat pump according to claim 4, wherein after the defrosting operation is started, the circulation flow rate of the antifreeze is firstly reduced to about 5% of the normal flow rate, the resistance heater is started to heat the flowing antifreeze, the temperature is controlled to be above 5 ℃ after heating, the hot antifreeze flows into the ambient air heat exchanger tube, frost is ablated at the interface of the tube wall, a frost layer condensed on the tube wall naturally peels off, and the temperature of the antifreeze flowing out of the ambient air heat exchanger reaches 0 ℃, so that the defrosting operation is finished.
6. The method for determining frosting and online defrosting of an enlarged air source heat pump according to claim 5, wherein when the defrosting operation is finished, the heating of the resistance heater is stopped, the circulation flow rate of the antifreeze solution is recovered, and the system is recovered to normal operation.
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100734537B1 (en) * | 2005-03-04 | 2007-07-04 | 엘에스전선 주식회사 | Operation Algorithm for Removing Frost in a Gas Engine Heat Pump System And Apparatus therefor |
| JP2011127853A (en) * | 2009-12-18 | 2011-06-30 | Mitsubishi Electric Corp | Heat pump device |
| JP2014094676A (en) * | 2012-11-09 | 2014-05-22 | Sanden Corp | Air conditioner for vehicle |
| CN106403422A (en) * | 2016-09-21 | 2017-02-15 | 广东工业大学 | Defrosting start point judgment method and defrosting start point judgment system for multi-loop heat exchanger of air source heat pump |
| WO2017096595A1 (en) * | 2015-12-10 | 2017-06-15 | 暵旸绿能科技股份有限公司 | Heat pump system |
| CN107763896A (en) * | 2017-12-01 | 2018-03-06 | 青岛新欧亚能源有限公司 | A kind of Split type air source heat pump system |
| CN107917561A (en) * | 2016-10-11 | 2018-04-17 | 青岛海尔新能源电器有限公司 | The defroster and Teat pump boiler of a kind of Teat pump boiler |
| CN110173940A (en) * | 2019-05-24 | 2019-08-27 | 百尔制冷(无锡)有限公司 | A method of control aerial cooler starting defrosting |
| CN209341628U (en) * | 2019-01-11 | 2019-09-03 | 山东美天能源科技有限公司 | A kind of self-defrosting type mine wind-lack heat energy deep exploitation device |
-
2019
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Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100734537B1 (en) * | 2005-03-04 | 2007-07-04 | 엘에스전선 주식회사 | Operation Algorithm for Removing Frost in a Gas Engine Heat Pump System And Apparatus therefor |
| JP2011127853A (en) * | 2009-12-18 | 2011-06-30 | Mitsubishi Electric Corp | Heat pump device |
| JP2014094676A (en) * | 2012-11-09 | 2014-05-22 | Sanden Corp | Air conditioner for vehicle |
| WO2017096595A1 (en) * | 2015-12-10 | 2017-06-15 | 暵旸绿能科技股份有限公司 | Heat pump system |
| CN106403422A (en) * | 2016-09-21 | 2017-02-15 | 广东工业大学 | Defrosting start point judgment method and defrosting start point judgment system for multi-loop heat exchanger of air source heat pump |
| CN107917561A (en) * | 2016-10-11 | 2018-04-17 | 青岛海尔新能源电器有限公司 | The defroster and Teat pump boiler of a kind of Teat pump boiler |
| CN107763896A (en) * | 2017-12-01 | 2018-03-06 | 青岛新欧亚能源有限公司 | A kind of Split type air source heat pump system |
| CN209341628U (en) * | 2019-01-11 | 2019-09-03 | 山东美天能源科技有限公司 | A kind of self-defrosting type mine wind-lack heat energy deep exploitation device |
| CN110173940A (en) * | 2019-05-24 | 2019-08-27 | 百尔制冷(无锡)有限公司 | A method of control aerial cooler starting defrosting |
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