CN105092220A - Fault detection method and device for supercooling valve in supercooling device - Google Patents

Abstract

The invention discloses a fault detection method and device for a supercooling valve in a supercooling device, and the method comprises the steps: detecting a main inflowing temperature value and a main outflowing temperature value of a supercooling heat exchanger at preset time intervals till the number of detection times reaches a preset number, and juding whether there is an abnormality happening to the supercooling valve or not according to the corresponding main inflowing and outflowing temperature values at each time; controlling the supercooling valve to be switched to a first switching degree when the abnormality happens to the supercooling valve, obtaining a first temperature difference value, controlling the supercooling valve to be switched to a second switching degree, and obtaining a second temperature difference value; judging whether the difference between the first temperature difference value and the second temperature difference value is less than or equal to a preset threshold value or not; and judging that a fault happens to the supercooling valve when the difference between the first temperature difference value and the second temperature difference value is less than or equal to the preset threshold value. The method provided by the embodiment of the invention can detect a plurality of types of faults of the supercooling valves, improves the satisfaction degree of a user, and protects an air conditioner from being further damaged.

Description

Fault detection method and the device of low temperature valve is crossed in supercooling apparatus

Technical field

The present invention relates to air conditioner technical field, particularly in a kind of supercooling apparatus, cross fault detection method and the device of low temperature valve.

Background technology

At field of central air-conditioning, the advantage that multi-joint unit is applied widely with it, application scenario is many is more and more favored by market.But it is well known that multi-joint unit capacity loss in Super long tube situation is more.For retrieving the capacity loss that refrigerant flash distillation in Super long tube causes, simultaneously also for eliminating the noise problem that two-phase flow brings, applying more and more in the industry and coldly solving the problems referred to above.And instantly, effective fault detect, anticipation, alarm method are but lacked for the low temperature valve (being a kind of electric expansion valve) of crossing generally applied in supercooling apparatus.

Although there is the fault detection method of some electric expansion valves in correlation technique, but these methods can only detect based on electronic expansion valve portion specific fault reason and judge electric expansion valve fault, and the electric expansion valve fault that other reason causes can not be detected.Such as, propose a kind of wire break detection method of stepper motor in correlation technique, the method is detection stepper motor electric signal and by this signal feedback to control section, control section reads value of feedback and also makes fault diagnosis.This kind of method can only detected electrons expansion valve stepper motor line fault; other fault (such as valve body step-out, stuck etc.) just has no way of detecting; more leisure opinion is optimized system by the suitable adjustment of valve body, is protected, thus causes poor user experience.Judge low temperature valve fault as in conjunction with supercooling apparatus actual conditions, be also in space state at present in the industry.

Summary of the invention

The present invention is intended to solve one of technical matters in correlation technique at least to a certain extent.For this reason, first object of the present invention is the fault detection method proposing low temperature valve excessively in a kind of supercooling apparatus.The method can detect the various faults appearing low temperature valve, namely improves the satisfaction of user, turn avoid the further damage of air conditioner.

Second object of the present invention is the failure detector proposing to cross low temperature valve in a kind of supercooling apparatus.

To achieve these goals, the fault detection method of low temperature valve is crossed in the supercooling apparatus of first aspect present invention embodiment, comprise the following steps: the main flow being detected cold heat exchanger every Preset Time enters temperature value and main flow goes out temperature value, until detect number of times to reach preset times, and detect corresponding described main flow and enter temperature value and described main flow according to each and go out temperature value and judged whether low temperature valve exception occurs; When the generation of described low temperature valve is excessively abnormal, control described low temperature valve of crossing open to the first aperture and obtain the first temperature difference, and control described cross low temperature valve open to the second aperture and obtain the second temperature difference, wherein, described first temperature difference is that described low temperature valve of crossing is opened to go out temperature value and described main flow to main flow described during the first aperture and enter difference between temperature value, and described second temperature difference is that described low temperature valve of crossing is opened to go out temperature value and described main flow to main flow described during the second aperture and enter difference between temperature value; Judge whether the difference between described first temperature difference and described second temperature difference is less than or equal to predetermined threshold value; And the difference between described first temperature difference and described second temperature difference is when being less than or equal to predetermined threshold value, judge that described low temperature valve of crossing breaks down.

According to the fault detection method crossing low temperature valve in the supercooling apparatus of the embodiment of the present invention, be detected temperature difference between cold heat exchanger import and outlet, and judged whether low temperature valve exception occurs according to the secondary temperature difference obtained that detects of continuous preset times, and when judging that low temperature valve occurred abnormal, controlled low temperature valve open to the first aperture and obtain the first temperature difference, and controlled low temperature valve and open to the second aperture and obtain the second temperature difference, then judged whether low temperature valve breaks down according to the first temperature difference and the second temperature difference, the method can detect the various faults (step-out appearing low temperature valve, stuck, impurity blocks, asynchronous machine open circuit etc.), be convenient to user or after sale personnel follow up maintenance and safeguard, prevent air conditioner long-time running under mistake low temperature valve failure condition from causing air conditioner further to damage, not only improve the satisfaction of user but also extend the serviceable life of air conditioner.

In one embodiment of the invention, described main flow enters temperature value and enters the acquisition of temperature-sensitive bag by main flow, described main flow enters temperature-sensitive bag and is arranged on and describedly crosses the entrance of cold heat exchanger and do not cross after low temperature valve described, described main flow goes out temperature value and goes out the acquisition of temperature-sensitive bag by main flow, and described main flow goes out temperature-sensitive bag and is arranged on described outlet of crossing cold heat exchanger.

In one embodiment of the invention, the described main flow of described acquisition enters temperature value and specifically comprises: the force value of detected pressures sensor, and described pressure transducer is arranged on describedly to be crossed the entrance of cold heat exchanger and does not cross after low temperature valve described; Obtain described main flow according to described force value and enter temperature.

In one embodiment of the invention, described basis detects corresponding described main flow at every turn and enters temperature value and described main flow and go out temperature and judged whether low temperature valve occurs extremely specifically to comprise: obtain and describedly detect corresponding described main flow and go out temperature value and described main flow and enter difference between temperature value at every turn; Obtain the degree of deviation according to described difference and preset temperature difference, and the described difference corresponding to every twice detection obtains change degree; When the described degree of deviation is all greater than predetermined deviation degree threshold value and described change degree is all less than default change degree threshold value, judge that described low temperature valve of crossing occurs abnormal.

In one embodiment of the invention, when described difference between described first temperature difference and described second temperature difference is less than or equal to predetermined threshold value, judge that described low temperature valve excessively breaks down specifically to comprise: when the difference between described first temperature difference and described second temperature difference is less than or equal to predetermined threshold value, control described cross low temperature valve repeatedly open and close k time, k be more than or equal to 1 integer; Control described cross low temperature valve open to described first aperture and obtain described first temperature difference, and control described cross low temperature valve open to described second aperture and obtain described second temperature difference; And the difference between described first temperature difference and described second temperature difference is when being still less than or equal to described predetermined threshold value, judge that described low temperature valve of crossing breaks down.

In one embodiment of the invention, also comprise: show failure message or carry out fault prompting, keeping in repair to point out user.

In one embodiment of the invention, also comprise: when the difference between described first temperature difference and described second temperature difference is greater than described predetermined threshold value, judge that described low temperature valve of crossing recovers normal.

In one embodiment of the invention, the described degree of deviation obtains according to following formula:

d＝|ΔTs-ΔTn _i|/ΔTs，

Wherein, d is the described degree of deviation, and Δ Ts is described preset temperature difference, Δ Tn _ibe detect corresponding described main flow for i-th time to go out temperature value and described main flow and enter difference between temperature value, Δ Tn _i=TOn _i-TIn _i, TOn _idescribed main flow when being i-th detection goes out temperature value, TIn _idescribed main flow when being i-th detection enters temperature value, and wherein i is integer, and 1≤i≤m, m is described preset times.

In one embodiment of the invention, described change degree obtains according to following formula:

c＝|ΔTn _i-ΔTn _j|/ΔTn _i，

Wherein, c is described change degree, Δ Tn _ibe detect corresponding described main flow for i-th time to go out temperature value and described main flow and enter difference between temperature value, Δ Tn _i=TOn _i-TIn _i, TOn _idescribed main flow when being i-th detection goes out temperature value, TIn _idescribed main flow when being i-th detection enters temperature value, Δ Tn _jgo out temperature value and described main flow enter difference between temperature value, Δ Tn for jth time detects corresponding described main flow _j=TOn _j-TIn _j, TOn _jfor described main flow when jth time detects goes out temperature value, TIn _jfor described main flow when jth time detects enters temperature value, wherein i, j are integer, and 1≤i, j≤m, i ≠ j, m is described preset times.

In one embodiment of the invention, described low temperature valve is excessively electric expansion valve.

To achieve these goals, the failure detector of low temperature valve is crossed in the supercooling apparatus of second aspect present invention embodiment, comprise: detection module, the main flow for being detected cold heat exchanger every Preset Time enters temperature value and main flow goes out temperature value, until detect number of times to reach preset times; Abnormal judge module, for detecting corresponding described main flow and enter temperature value and described main flow according to each and go out temperature value and judged whether low temperature valve exception occurs; Control module, for when the generation of described low temperature valve is excessively abnormal, control described low temperature valve of crossing open to the first aperture and obtain the first temperature difference, and control described cross low temperature valve open to the second aperture and obtain the second temperature difference, wherein, described first temperature difference is that described low temperature valve of crossing is opened to go out temperature value and described main flow to main flow described during the first aperture and enter difference between temperature value, and described second temperature difference is that described low temperature valve of crossing is opened to go out temperature value and described main flow to main flow described during the second aperture and enter difference between temperature value; Judge module, for judging whether the difference between described first temperature difference and described second temperature difference is less than or equal to predetermined threshold value; And breakdown judge module, when being less than or equal to predetermined threshold value for the difference between described first temperature difference and described second temperature difference, judge that described low temperature valve of crossing breaks down.

According to the failure detector crossing low temperature valve in the supercooling apparatus of the embodiment of the present invention, the temperature difference between cold heat exchanger import and outlet is detected by detection module, abnormal judge module detects according to continuous preset times time the temperature difference obtained and judged whether low temperature valve exception occurs, and when judging that low temperature valve occurred abnormal, control module controlled low temperature valve and opens to the first aperture and obtain the first temperature difference, and controlled low temperature valve and open to the second aperture and obtain the second temperature difference, then according to the first temperature difference and the second temperature difference, breakdown judge module judged whether low temperature valve breaks down, this device can detect the various faults (step-out appearing low temperature valve, stuck, impurity blocks, asynchronous machine open circuit etc.), be convenient to user or after sale personnel follow up maintenance and safeguard, prevent air conditioner long-time running under mistake low temperature valve failure condition from causing air conditioner further to damage, not only improve the satisfaction of user but also extend the serviceable life of air conditioner.

In one embodiment of the invention, described abnormal judge module comprises: the first acquiring unit, described for obtaining detect corresponding described main flow and goes out temperature value and described main flow and enter difference between temperature value at every turn; Second acquisition unit, for obtaining the degree of deviation according to described difference and preset temperature difference, and the described difference corresponding to every twice detection obtains change degree; Abnormal deciding means, for when the described degree of deviation is all greater than predetermined deviation degree threshold value and described change degree is all less than default change degree threshold value, judges that described low temperature valve of crossing occurs abnormal.

In one embodiment of the invention, described breakdown judge module comprises: the first control module, when being less than or equal to predetermined threshold value for the difference between described first temperature difference and described second temperature difference, control described cross low temperature valve repeatedly open and close k time, k be more than or equal to 1 integer; Second control module, for control described cross low temperature valve open to described first aperture and obtain described first temperature difference, and control described cross low temperature valve open to described second aperture and obtain described second temperature difference; And breakdown judge unit, when being still less than or equal to described predetermined threshold value for the difference between described first temperature difference and described second temperature difference, judge that described low temperature valve of crossing breaks down.

In one embodiment of the invention, also comprise: fault cues module, for showing failure message or carrying out fault prompting, keep in repair to point out user.

In one embodiment of the invention, described breakdown judge unit also for, when the difference between described first temperature difference and described second temperature difference is greater than described predetermined threshold value, judge that described low temperature valve of crossing recovers normal.

In one embodiment of the invention, the described degree of deviation obtains according to following formula:

d＝|ΔTs-ΔTn _i|/ΔTs，

Wherein, d is the described degree of deviation, and Δ Ts is described preset temperature difference, Δ Tn _ibe detect corresponding described main flow for i-th time to go out temperature value and described main flow and enter difference between temperature value, Δ Tn _i=TOn _i-TIn _i, TOn _idescribed main flow when being i-th detection goes out temperature value, TIn _idescribed main flow when being i-th detection enters temperature value, and wherein i is integer, and 1≤i≤m, m is described preset times.

In one embodiment of the invention, described change degree obtains according to following formula:

c＝|ΔTn _i-ΔTn _j|/ΔTn _i，

Wherein, c is described change degree, Δ Tn _ibe detect corresponding described main flow for i-th time to go out temperature value and described main flow and enter difference between temperature value, Δ Tn _i=TOn _i-TIn _i, TOn _idescribed main flow when being i-th detection goes out temperature value, TIn _idescribed main flow when being i-th detection enters temperature value, Δ Tn _jgo out temperature value and described main flow enter difference between temperature value, Δ Tn for jth time detects corresponding described main flow _j=TOn _j-TIn _j, TOn _jfor described main flow when jth time detects goes out temperature value, TIn _jfor described main flow when jth time detects enters temperature value, wherein i, j are integer, and 1≤i, j≤m, i ≠ j, m is described preset times.

In one embodiment of the invention, described low temperature valve is excessively electric expansion valve.

Accompanying drawing explanation

Fig. 1 is the process flow diagram of the fault detection method crossing low temperature valve according to an embodiment of the invention in supercooling apparatus;

Fig. 2 (a) is the structural representation of supercooling apparatus according to an embodiment of the invention;

Fig. 2 (b) is the structural representation of supercooling apparatus in accordance with another embodiment of the present invention;

Fig. 3 detects corresponding main flow and enters temperature value and main flow according to each and go out temperature and judged whether low temperature valve abnormal process flow diagram occurs according to an embodiment of the invention;

Fig. 4 is according to an embodiment of the invention when the difference of the first temperature difference and the second temperature difference is less than or equal to predetermined threshold value, judges the process flow diagram that low temperature valve breaks down;

Fig. 5 is the structural representation of the failure detector crossing low temperature valve according to an embodiment of the invention in supercooling apparatus;

Fig. 6 is the structural representation of the failure detector crossing low temperature valve according to an embodiment of the invention in supercooling apparatus;

Fig. 7 is the structural representation of the failure detector crossing low temperature valve in accordance with another embodiment of the present invention in supercooling apparatus;

Fig. 8 is the structural representation of the failure detector crossing low temperature valve in the supercooling apparatus according to another embodiment of the present invention.

Reference numeral: detection module 100, abnormal judge module 200, control module 300, judge module 400, breakdown judge module 500, first acquiring unit 210, second acquisition unit 220, abnormal deciding means 230, first control module 510, second control module 520, breakdown judge unit 530, fault cues module 600.

Embodiment

Be described below in detail embodiments of the invention, the example of described embodiment is shown in the drawings, and wherein same or similar label represents same or similar element or has element that is identical or similar functions from start to finish.Be exemplary below by the embodiment be described with reference to the drawings, be intended to for explaining the present invention, and can not limitation of the present invention be interpreted as.

Below with reference to the accompanying drawings the fault detect detection method and device of crossing low temperature valve in supercooling apparatus according to the embodiment of the present invention are described.

Fig. 1 is the process flow diagram of the fault detection method crossing low temperature valve according to an embodiment of the invention in supercooling apparatus.As shown in Figure 1, the fault detection method crossing low temperature valve in the supercooling apparatus of the embodiment of the present invention comprises the steps.

S101, the main flow being detected cold heat exchanger every Preset Time enters temperature value and main flow goes out temperature value, until detect number of times to reach preset times, and detects corresponding main flow and enters temperature value and main flow according to each and go out temperature value and judged whether low temperature valve exception occurs.

Particularly, in the indoor set of air conditioner or off-premises station, there is supercooling apparatus.When the duty of air conditioner be refrigerating state or heat state time, in supercooling apparatus, refrigerant flows to contrary.

In one embodiment of the invention, crossing low temperature valve is electric expansion valve.

The fault detection method crossing low temperature valve in the supercooling apparatus of the embodiment of the present invention is described for the refrigerating state of air conditioner below.

In one embodiment of the invention, the main flow crossing cold heat exchanger enters temperature value and enters the acquisition of temperature-sensitive bag by main flow, main flow enters temperature-sensitive bag and was arranged on the entrance of cold heat exchanger and was not crossing after low temperature valve, main flow goes out temperature value and goes out the acquisition of temperature-sensitive bag by main flow, and main flow goes out the outlet that temperature-sensitive bag was arranged on cold heat exchanger.

Particularly, as Fig. 2 (a) is depicted as the structural representation of supercooling apparatus, wherein, 10 go out temperature-sensitive bag for main flow, and 11 enter temperature-sensitive bag for main flow, and 12 is main electric expansion valve, and 13 was low temperature valve, and 14 was cold heat exchanger.In refrigerating operaton process, off-premises station controlled low temperature valve aperture according to preset program.

Particularly, in the normal refrigerating operaton process of air conditioner, along with the propelling of time, crossing the aperture of low temperature valve is change, and main flow enters temperature value and main flow, and to go out temperature value be also change.In the refrigerating operaton process of air conditioner, detect with the equal time interval (i.e. Preset Time) main flow that main flow enters temperature-sensitive bag 11 and enter the main flow that temperature value TIn and main flow go out temperature-sensitive bag 10 and go out temperature value TOn, until detect number of times to reach preset times.Such as, Preset Time can be 1min, and preset times can be 10 times, and so total detection time is 10 minutes.More specifically, occur abnormal if cross low temperature valve, generally there will be that the temperature difference between the import of cold heat exchanger 14 and outlet (namely main flow goes out temperature value and main flow and enters difference between temperature value) is long-time not to be changed or microvariations and the temperature difference between import and outlet depart from setting value always.So, corresponding main flow can be detected enter temperature value and main flow and go out temperature value to judge low temperature valve and whether exception occurs according to each.Such as, continuous detecting 10 times, if each temperature difference crossed between the import of cold heat exchanger 14 and outlet changes hardly or microvariations and the temperature difference between each import and outlet all depart from setting value, so just illustrated that low temperature valve there occurs exception.

In another embodiment of the present invention, cross the main flow of cold heat exchanger and enter temperature value and can be converted by the force value of pressure transducer and obtain, pressure transducer be arranged on cold heat exchanger entrance and not after crossing low temperature valve.As Fig. 2 (b) is depicted as the structural representation of supercooling apparatus, wherein, 10 go out temperature-sensitive bag for main flow, and 11 is pressure transducer, and 12 is main electric expansion valve, and 13 was low temperature valve, and 14 was cold heat exchanger.Particularly, the first force value of detected pressures sensor 11, then calculate corresponding saturation temperature value according to the force value detected, namely main flow enters temperature value.It is more accurate that the main flow obtained in this way enters temperature value.

S102, when having served as low temperature valve generation exception, controlled low temperature valve open to the first aperture and obtain the first temperature difference, and controlled low temperature valve and open to the second aperture and obtain the second temperature difference, wherein, first temperature difference was that low temperature valve is opened to go out temperature value and main flow to main flow during the first aperture and enter difference between temperature value, and the second temperature difference was that low temperature valve is opened to go out temperature value and main flow to main flow during the second aperture and enter difference between temperature value.

Particularly, such as, when having served as low temperature valve generation exception, controlling low temperature valve opens to the first aperture (minimum aperture, be designated as EVmin) and obtain the first temperature difference (being designated as Δ Tmin), and controlled low temperature valve and open to the second aperture (maximum opening is designated as EVmax) and obtain the second temperature difference (being designated as Δ Tmax).Wherein, the first temperature difference was that low temperature valve is opened to go out temperature value and main flow to main flow during minimum aperture and enter difference between temperature value, and the second temperature difference was that low temperature valve is opened to go out temperature value and main flow to main flow during maximum opening and enter difference between temperature value.

S103, judges whether the difference between the first temperature difference and the second temperature difference is less than or equal to predetermined threshold value.

Particularly, such as, judging whether the first temperature difference and the second temperature difference meet | Δ Tmax-Δ Tmin|≤c1, wherein, c1 is predetermined threshold value, and c1 is a smaller value.

S104, when the difference between the first temperature and the second temperature difference is less than or equal to predetermined threshold value, judged that low temperature valve broke down.

Particularly, when | during Δ Tmax-Δ Tmin|≤c1, judged that low temperature valve broke down, and such as, crossed low temperature valve and be in the unadjustable states such as step-out, stuck, impurity blocking, asynchronous machine open circuit.

The fault detection method crossing low temperature valve for air conditioner of the embodiment of the present invention, be detected temperature difference between cold heat exchanger import and outlet, and judged whether low temperature valve exception occurs according to the secondary temperature difference obtained that detects of continuous preset times, and when judging that low temperature valve occurred abnormal, controlled low temperature valve open to the first aperture and obtain the first temperature difference, and controlled low temperature valve and open to the second aperture and obtain the second temperature difference, then judged whether low temperature valve breaks down according to the first temperature difference and the second temperature difference, the method can detect the various faults (step-out appearing low temperature valve, stuck, impurity blocks, asynchronous machine open circuit etc.), be convenient to user or after sale personnel follow up maintenance and safeguard, prevent air conditioner long-time running under mistake low temperature valve failure condition from causing air conditioner further to damage, not only improve the satisfaction of user but also extend the serviceable life of air conditioner.

In one embodiment of the invention, as shown in Figure 3, detect corresponding main flow and enter temperature value and main flow according to each and go out temperature and judged whether low temperature valve occurs extremely specifically to comprise the following steps.

S201, obtains and each detect corresponding main flow and go out temperature value and main flow and enter difference between temperature value.

Particularly, detect corresponding main flow for i-th time to go out temperature value and main flow and enter difference DELTA Tn between temperature _ifor: Δ Tn _i=TOn _i-TIn _i, TOn _imain flow when being i-th detection goes out temperature value, TIn _imain flow when being i-th detection enters temperature value, and wherein i is integer, and 1≤i≤m, m is preset times, the preset times namely detected.

S202, obtains the degree of deviation according to difference and preset temperature difference, and the difference corresponding to every twice detection obtains change degree.

In an embodiment of the present invention, the degree of deviation obtains according to following formula (1):

d＝|ΔTs-ΔTn _i|/ΔTs，(1)

Wherein, d is the degree of deviation, and Δ Ts is preset temperature difference, Δ Tn _ibe detect corresponding main flow for i-th time to go out temperature value and main flow and enter difference between temperature value, Δ Tn _i=TOn _i-TIn _i, TOn _imain flow when being i-th detection goes out temperature value, and main flow when TIni is i-th detection enters temperature value, and wherein i is integer, and 1≤i≤m, m is preset times.

In an embodiment of the present invention, change degree obtains according to following formula (2):

c＝|ΔTn _i-ΔTn _j|/ΔTn _i，(2)

Wherein, c is change degree, Δ Tn _ibe detect corresponding main flow for i-th time to go out temperature value and main flow and enter difference between temperature value, Δ Tn _i=TOn _i-TIn _i, TOn _imain flow when being i-th detection goes out temperature value, TIn _imain flow when being i-th detection enters temperature value, Δ Tn _jgo out temperature value and main flow enter difference between temperature value, Δ Tn for jth time detects corresponding main flow _j=TOn _j-TIn _j, TOn _jfor main flow when jth time detects goes out temperature value, TIn _jfor main flow when jth time detects enters temperature value, wherein i, j are integer, and 1≤i, j≤m, i ≠ j, m is preset times.

S203, when the degree of deviation is all greater than predetermined deviation degree threshold value and change degree is all less than default change degree threshold value, judged that low temperature valve occurred abnormal.

Particularly, if for continuous m (preset times) secondary detection, each detection all meets d >=a and c≤b (a is predetermined deviation degree threshold value, b is for presetting change degree threshold value, b is a minimum value and a>>b) time, namely at every turn detect time heat exchanger assembly import and outlet between the temperature difference all depart from setting value (predetermined deviation degree threshold value a) and the import of heat exchanger assembly and export between the temperature difference change hardly or microvariations, so just illustrated that low temperature valve may have occurred step-out, stuck, the faults such as impurity blocking or asynchronous machine open circuit.

In one embodiment of the invention, as shown in Figure 4, when the difference of the first temperature difference and the second temperature difference is less than or equal to predetermined threshold value, judged that low temperature valve broke down and specifically comprised the following steps.

S301, when the difference of the first temperature and the second temperature difference is less than or equal to predetermined threshold value, controlled low temperature valve and repeatedly opens and close k time, k be more than or equal to 1 integer.

Particularly, when the difference of the first temperature and the second temperature difference is less than or equal to predetermined threshold value, illustrated that low temperature valve was in the unadjustable states such as step-out, stuck, impurity blocking, asynchronous machine open circuit, so now controlled low temperature valve and carried out self-regeneration, namely controlled low temperature valve and repeatedly open and close several times.

S302, controlled low temperature valve and opens to the first aperture and obtain the first temperature difference, and controlled low temperature valve and open to the second aperture and obtain the second temperature difference.

Particularly, controlled low temperature valve repeatedly to open and after closing several times, controlled low temperature valve open to the first aperture (i.e. minimum aperture EVmin) and obtain the first temperature difference (Δ Tmin), and controlled low temperature valve and open to the second aperture (i.e. maximum opening EVmax) and obtain the second temperature difference (Δ Tmax).

S303, when the difference of the first temperature difference and the second temperature difference is still less than or equal to predetermined threshold value, judged that low temperature valve broke down.

Particularly, again compare the difference of the first temperature difference and the second temperature difference | the size of Δ Tmax-Δ Tmin| and predetermined threshold value c1, when the difference of the first temperature difference and the second temperature difference still meets | during Δ Tmax-Δ Tmin|≤c1, judged that low temperature valve broke down.

In one embodiment of the invention, also comprise: when the difference of the first temperature difference and the second temperature difference is greater than predetermined threshold value, judged that low temperature valve recovered normal.Particularly, if | Δ Tmax-Δ Tmin| > c1, then judged that low temperature valve recovered normal.Namely cross low temperature valve repeatedly open and close several times, self-regeneration success, cross low temperature valve and recover normal.

In an embodiment of invention, after judging that low temperature valve broke down, also comprised: show failure message or carry out fault prompting, keeping in repair to point out user.

The fault detection method of low temperature valve is crossed in the supercooling apparatus of the embodiment of the present invention, when the difference of the first temperature and the second temperature difference is less than or equal to predetermined threshold value, control low temperature valve and carry out self-regeneration, namely controlled low temperature valve repeatedly open and close several times, and then once controlled low temperature valve and open to the first aperture and obtain the first temperature difference, and controlled low temperature valve and open to the second aperture and obtain the second temperature difference, if the difference between the first temperature difference and the second temperature difference is still less than or equal to predetermined threshold value, then judged that low temperature valve broke down; If the difference between the first temperature difference and the second temperature difference becomes be greater than predetermined threshold value, then judged that low temperature valve recovered normal.If long-time running under low temperature valve failure condition crossed by air conditioner, high temperature, high pressure, low pressure can be brought, return the series of problems such as liquid, oily dilution, thus cause the further damage of air conditioner, therefore, the method can detect the fault appearing low temperature valve, and appears in detection and to show failure message after low temperature valve breaks down or carry out fault prompting, keeps in repair to point out user, thus prevent the further damage of air conditioner, improve the satisfaction of user.

In addition, it should be noted that, in the above supercooling apparatus all described for the refrigerating state of air conditioner, cross the fault detection method of low temperature valve, when air conditioner be in heat state time, the fault detection method crossing low temperature valve in supercooling apparatus is suitable for too, does not repeat them here.Difference is, when air conditioner be in heat state time, refrigerant flows to contrary, outlet when entrance during refrigeration is outlet when heating, refrigeration is entrance when heating, and the difference between the first temperature difference corresponding when also having low temperature valve aperture to be the first aperture, the second aperture and the second temperature difference is different.

In order to realize above-described embodiment, the present invention also proposes the failure detector crossing low temperature valve in a kind of supercooling apparatus.

Fig. 5 is the structural representation of the failure detector crossing low temperature valve according to an embodiment of the invention in supercooling apparatus.As shown in Figure 5, the failure detector crossing low temperature valve in the supercooling apparatus of the embodiment of the present invention comprises: detection module 100, abnormal judge module 200, control module 300, judge module 400 and breakdown judge module 500.

In one embodiment of the invention, crossing low temperature valve is electric expansion valve.

Wherein, detection module 100 enters temperature value for the main flow being detected cold heat exchanger every Preset Time and main flow goes out temperature value, until detect number of times to reach preset times.

Particularly, in the indoor set of air conditioner or off-premises station, there is supercooling apparatus.When the duty of air conditioner be refrigerating state or heat state time, in supercooling apparatus, refrigerant flows to contrary.

Below citing all illustrates with the refrigerating state of air conditioner.

In one embodiment of the invention, the main flow crossing cold heat exchanger enters temperature value and enters the acquisition of temperature-sensitive bag by main flow, main flow enters temperature-sensitive bag and was arranged on the entrance of cold heat exchanger and was not crossing after low temperature valve, main flow goes out temperature value and goes out the acquisition of temperature-sensitive bag by main flow, and main flow goes out the outlet that temperature-sensitive bag was arranged on cold heat exchanger.

Particularly, as Fig. 2 (a) is depicted as the structural representation of supercooling apparatus, wherein, 10 go out temperature-sensitive bag for main flow, and 11 enter temperature-sensitive bag for main flow, and 12 is main electric expansion valve, and 13 was low temperature valve, and 14 was cold heat exchanger.In refrigerating operaton process, indoor set controlled low temperature valve aperture according to preset program.

Particularly, in the normal refrigerating operaton process of air conditioner, along with the propelling of time, crossing the aperture of low temperature valve is change, and main flow enters temperature value and main flow, and to go out temperature value be also change.In air conditioner refrigerating operaton process, detection module 100 enters temperature-sensitive bag 11 main flow for detecting main flow with the equal time interval (i.e. Preset Time) enters the main flow that temperature value TIn and main flow go out temperature-sensitive bag 10 and goes out temperature value TOn, until detect number of times to reach preset times.Such as, Preset Time can be 1min, and preset times can be 10 times, and so total detection time is 10 minutes.

In another embodiment of the present invention, cross the main flow of cold heat exchanger and enter temperature value and can be converted by the force value of pressure transducer and obtain, pressure transducer be arranged on cold heat exchanger entrance and not after crossing low temperature valve.As Fig. 2 (b) is depicted as the structural representation of supercooling apparatus, wherein, 10 go out temperature-sensitive bag for main flow, and 11 is pressure transducer, and 12 is main electric expansion valve, and 13 was low temperature valve, and 14 was cold heat exchanger.Particularly, the first force value of detected pressures sensor 11, then calculate corresponding saturation temperature value according to the force value detected, namely main flow enters temperature value.It is more accurate that the main flow obtained in this way enters temperature value.

Abnormal judge module 200 is for detecting corresponding main flow and enter temperature value and main flow according to each and go out temperature value and judged whether low temperature valve exception occurs.

Particularly, occur abnormal if cross low temperature valve, generally there will be that the temperature difference between the import of cold heat exchanger 14 and outlet (namely main flow goes out temperature value and main flow and enters difference between temperature value) is long-time not to be changed or microvariations and the temperature difference between import and outlet depart from setting value always.So abnormal judge module 200 is for detecting corresponding main flow and enter temperature value and main flow according to each and go out temperature value to judge low temperature valve and whether exception occurs.Such as, continuous detecting 10 times, if each temperature difference crossed between the import of cold heat exchanger 14 and outlet changes hardly or microvariations and the temperature difference between each import and outlet all depart from setting value, so just illustrated that low temperature valve there occurs exception.

When control module 300 occurs abnormal for having served as low temperature valve, controlled low temperature valve open to the first aperture and obtain the first temperature difference, and controlled low temperature valve and open to the second aperture and obtain the second temperature difference, wherein, first temperature difference was that low temperature valve is opened to go out temperature and main flow to main flow during the first aperture and enter difference between temperature value, and the second temperature difference was that low temperature valve is opened to go out temperature and main flow to main flow during the second aperture and enter difference between temperature value.

Particularly, such as, when having served as low temperature valve generation exception, control module 300 is opened to the first aperture (minimum aperture for controlling low temperature valve, be designated as EVmin) and obtain the first temperature difference (being designated as Δ Tmin), and controlled low temperature valve and open to the second aperture (maximum opening is designated as EVmax) and obtain the second temperature difference (being designated as Δ Tmax).Wherein, the first temperature difference was that low temperature valve is opened to go out temperature and main flow to main flow during minimum aperture and enter difference between temperature value, and the second temperature difference was that low temperature valve is opened to go out temperature and main flow to main flow during maximum opening and enter difference between temperature value.

Judge module 400 is for judging whether the difference between the first temperature difference and the second temperature difference is less than or equal to predetermined threshold value.

Particularly, such as, judge module 400 is for judging whether the first temperature difference and the second temperature difference meet | Δ Tmax-Δ Tmin|≤c1, wherein, c1 is predetermined threshold value, and c1 is a smaller value.

When breakdown judge module 500 is less than or equal to predetermined threshold value for the difference between the first temperature difference and the second temperature difference, judged that low temperature valve broke down.

Particularly, breakdown judge module 500 for when | during Δ Tmax-Δ Tmin|≤c1, judged that low temperature valve broke down, and such as, crossed low temperature valve and be in the unadjustable states such as step-out, stuck, impurity blocking, asynchronous machine open circuit.

The failure detector of low temperature valve is crossed in the supercooling apparatus of the embodiment of the present invention, the temperature difference between cold heat exchanger import and outlet is detected by detection module, abnormal judge module detects according to continuous preset times time the temperature difference obtained and judged whether low temperature valve exception occurs, and when judging that low temperature valve occurred abnormal, control module controlled low temperature valve and opens to the first aperture and obtain the first temperature difference, and controlled low temperature valve and open to the second aperture and obtain the second temperature difference, then according to the first temperature difference and the second temperature difference, breakdown judge module judged whether low temperature valve breaks down, this device can detect the various faults (step-out appearing low temperature valve, stuck, impurity blocks, asynchronous machine open circuit etc.), be convenient to user or after sale personnel follow up maintenance and safeguard, prevent air conditioner long-time running under mistake low temperature valve failure condition from causing air conditioner further to damage, not only improve the satisfaction of user but also extend the serviceable life of air conditioner.

In one embodiment of the invention, as shown in Figure 6, abnormal judge module 200 specifically comprises: the first acquiring unit 210, second acquisition unit 220 and abnormal deciding means 230.

Wherein, the first acquiring unit 210 each detect corresponding main flow for obtaining and goes out temperature value and main flow and enter difference between temperature value.

Particularly, detect corresponding main flow for i-th time to go out temperature value and main flow and enter difference DELTA Tn between temperature _ifor: Δ Tn _i=TOn _i-TIn _i, TOn _imain flow when being i-th detection goes out temperature value, TIn _imain flow when being i-th detection enters temperature value, and wherein i is integer, and 1≤i≤m, m is preset times, the preset times namely detected.

Second acquisition unit 220 is for obtaining the degree of deviation according to difference and preset temperature difference, and the difference corresponding to every twice detection obtains change degree.

In an embodiment of the present invention, the degree of deviation obtains according to following formula (1):

d＝|ΔTs-ΔTn _i|/ΔTs，(1)

Wherein, d is the degree of deviation, and Δ Ts is preset temperature difference, Δ Tn _ibe detect corresponding main flow for i-th time to go out temperature value and main flow and enter difference between temperature value, Δ Tn _i=TOn _i-TIn _i, TOn _imain flow when being i-th detection goes out temperature value, TIn _imain flow when being i-th detection enters temperature value, and wherein i is integer, and 1≤i≤m, m is preset times.

In an embodiment of the present invention, change degree obtains according to following formula (2):

c＝|ΔTn _i-ΔTn _j|/ΔTn _i，(2)

Wherein, c is change degree, Δ Tn _ibe detect corresponding main flow for i-th time to go out temperature value and main flow and enter difference between temperature value, Δ Tn _i=TOn _i-TIn _i, TOn _imain flow when being i-th detection goes out temperature value, TIn _imain flow when being i-th detection enters temperature value, Δ Tn _jgo out temperature value and main flow enter difference between temperature value, Δ Tn for jth time detects corresponding main flow _j=TOn _j-TIn _j, TOn _jfor main flow when jth time detects goes out temperature value, TIn _jfor main flow when jth time detects enters temperature value, wherein i, j are integer, and 1≤i, j≤m, i ≠ j, m is preset times.

Abnormal deciding means 230, for when the degree of deviation is all greater than predetermined deviation degree threshold value and change degree is all less than default change degree threshold value, judged that low temperature valve occurred abnormal.

Particularly, if for continuous m (preset times) secondary detection, each detection all meets d >=a and c≤b (a is predetermined deviation degree threshold value, b is for presetting change degree threshold value, b is a minimum value and a>>b) time, namely at every turn detect time heat exchanger assembly import and outlet between the temperature difference all depart from setting value (predetermined deviation degree threshold value a) and the import of heat exchanger assembly and export between the temperature difference change hardly or microvariations, so just illustrated that low temperature valve may have occurred step-out, stuck, the faults such as impurity blocking or asynchronous machine open circuit.

In one embodiment of the invention, as shown in Figure 7, breakdown judge module 500 comprises: the first control module 510, second control module 520 and breakdown judge unit 530.

First control module 510, for when the difference of the first temperature and the second temperature difference is less than or equal to predetermined threshold value, controlled low temperature valve and repeatedly opens and close k time, k be more than or equal to 1 integer.

Particularly, when the difference of the first temperature and the second temperature difference is less than or equal to predetermined threshold value, illustrated that low temperature valve was in the unadjustable states such as step-out, stuck, impurity blocking, asynchronous machine open circuit, so now the first control module 510 carried out self-regeneration for controlling low temperature valve, namely controlled low temperature valve and repeatedly opened and close several times.

Second control module 520 was opened to the first aperture for controlling low temperature valve and obtained the first temperature difference, and controlled low temperature valve and open to the second aperture and obtain the second temperature difference.

Particularly, first control module 510 controlled low temperature valve and repeatedly to open and after closing several times, second control module 520 controlled low temperature valve and opens to the first aperture (i.e. minimum aperture EVmin) and obtain the first temperature difference (Δ Tmin), and controlled low temperature valve and open to the second aperture (i.e. maximum opening EVmax) and obtain the second temperature difference (Δ Tmax).

Breakdown judge unit 530, for when the difference of the first temperature difference and the second temperature difference is still less than or equal to predetermined threshold value, judged that low temperature valve broke down.

Particularly, again compare the difference of the first temperature difference and the second temperature difference | the size of Δ Tmax-Δ Tmin| and predetermined threshold value c1, breakdown judge unit 530 is for still meeting when the difference of the first temperature difference and the second temperature difference | during Δ Tmax-Δ Tmin|≤c1, judged that low temperature valve broke down.

In one embodiment of the invention, breakdown judge unit 530 also for, when the difference between the first temperature difference and the second temperature difference is greater than predetermined threshold value, judged that low temperature valve recovered normal.Particularly, if | Δ Tmax-Δ Tmin| > c1, then breakdown judge unit 530 judged that low temperature valve recovered normal.Namely cross low temperature valve repeatedly open and close several times, self-regeneration success, cross low temperature valve and recover normal.

In an embodiment of invention, as shown in Figure 8, the failure detector crossing low temperature valve in supercooling apparatus also comprises: fault cues module 600.Fault cues module 600, for showing failure message or carrying out fault prompting, is keeped in repair to point out user.

The failure detector of low temperature valve is crossed in the supercooling apparatus of the embodiment of the present invention, when the difference of the first temperature and the second temperature difference is less than or equal to predetermined threshold value, first control module controlled low temperature valve and carried out self-regeneration, namely controlled low temperature valve repeatedly open and close several times, then the second control module controlled low temperature valve and opens to the first aperture and obtain the first temperature difference, and controlled low temperature valve and open to the second aperture and obtain the second temperature difference, if the difference between the first temperature difference and the second temperature difference is still less than or equal to predetermined threshold value, breakdown judge unit then judged that low temperature valve broke down, if the difference between the first temperature difference and the second temperature difference becomes be greater than predetermined threshold value, breakdown judge unit then judged that low temperature valve recovered normal.If long-time running under low temperature valve failure condition crossed by air conditioner, high temperature, high pressure, low pressure can be brought, return the series of problems such as liquid, oily dilution, thus cause the further damage of air conditioner, therefore, this device can detect the fault appearing low temperature valve, and detection appear low temperature valve break down after fault cues module display failure message or carry out fault prompting, keep in repair to point out user, thus prevent the further damage of air conditioner, improve the satisfaction of user.

In describing the invention, it will be appreciated that, term " " center ", " longitudinal direction ", " transverse direction ", " length ", " width ", " thickness ", " on ", D score, " front ", " afterwards ", " left side ", " right side ", " vertically ", " level ", " top ", " end " " interior ", " outward ", " clockwise ", " counterclockwise ", " axis ", " radial direction ", orientation or the position relationship of the instruction such as " circumference " are based on orientation shown in the drawings or position relationship, only the present invention for convenience of description and simplified characterization, instead of indicate or imply that the device of indication or element must have specific orientation, with specific azimuth configuration and operation, therefore limitation of the present invention can not be interpreted as.

In addition, term " first ", " second " only for describing object, and can not be interpreted as instruction or hint relative importance or imply the quantity indicating indicated technical characteristic.Thus, be limited with " first ", the feature of " second " can express or impliedly comprise at least one this feature.In describing the invention, the implication of " multiple " is at least two, such as two, three etc., unless otherwise expressly limited specifically.

In the present invention, unless otherwise clearly defined and limited, the term such as term " installation ", " being connected ", " connection ", " fixing " should be interpreted broadly, and such as, can be fixedly connected with, also can be removably connect, or integral; Can be mechanical connection, also can be electrical connection; Can be directly be connected, also indirectly can be connected by intermediary, can be the connection of two element internals or the interaction relationship of two elements, unless otherwise clear and definite restriction.For the ordinary skill in the art, above-mentioned term concrete meaning in the present invention can be understood as the case may be.

In the present invention, unless otherwise clearly defined and limited, fisrt feature second feature " on " or D score can be that the first and second features directly contact, or the first and second features are by intermediary indirect contact.And, fisrt feature second feature " on ", " top " and " above " but fisrt feature directly over second feature or oblique upper, or only represent that fisrt feature level height is higher than second feature.Fisrt feature second feature " under ", " below " and " below " can be fisrt feature immediately below second feature or tiltedly below, or only represent that fisrt feature level height is less than second feature.

In the description of this instructions, specific features, structure, material or feature that the description of reference term " embodiment ", " some embodiments ", " example ", " concrete example " or " some examples " etc. means to describe in conjunction with this embodiment or example are contained at least one embodiment of the present invention or example.In this manual, to the schematic representation of above-mentioned term not must for be identical embodiment or example.And the specific features of description, structure, material or feature can combine in one or more embodiment in office or example in an appropriate manner.In addition, when not conflicting, the feature of the different embodiment described in this instructions or example and different embodiment or example can carry out combining and combining by those skilled in the art.

Although illustrate and describe embodiments of the invention above, be understandable that, above-described embodiment is exemplary, can not be interpreted as limitation of the present invention, and those of ordinary skill in the art can change above-described embodiment within the scope of the invention, revises, replace and modification.

Claims (18)

1. cross a fault detection method for low temperature valve in supercooling apparatus, it is characterized in that, comprise the following steps:

The main flow being detected cold heat exchanger every Preset Time enters temperature value and main flow goes out temperature value, until detect number of times to reach preset times, and detects corresponding described main flow and enters temperature value and described main flow according to each and go out temperature value and judged whether low temperature valve exception occurs;

When the generation of described low temperature valve is excessively abnormal, control described low temperature valve of crossing open to the first aperture and obtain the first temperature difference, and control described cross low temperature valve open to the second aperture and obtain the second temperature difference, wherein, described first temperature difference is that described low temperature valve of crossing is opened to go out temperature value and described main flow to main flow described during the first aperture and enter difference between temperature value, and described second temperature difference is that described low temperature valve of crossing is opened to go out temperature value and described main flow to main flow described during the second aperture and enter difference between temperature value;

Judge whether the difference between described first temperature difference and described second temperature difference is less than or equal to predetermined threshold value; And

When difference between described first temperature difference and described second temperature difference is less than or equal to predetermined threshold value, judge that described low temperature valve of crossing breaks down.

2. in supercooling apparatus as claimed in claim 1, cross the fault detection method of low temperature valve, it is characterized in that, described main flow enters temperature value and enters the acquisition of temperature-sensitive bag by main flow, described main flow enters temperature-sensitive bag and is arranged on and describedly crosses the entrance of cold heat exchanger and do not cross after low temperature valve described, described main flow goes out temperature value and goes out the acquisition of temperature-sensitive bag by main flow, and described main flow goes out temperature-sensitive bag and is arranged on described outlet of crossing cold heat exchanger.

3. cross the fault detection method of low temperature valve in supercooling apparatus as claimed in claim 1, it is characterized in that, the described main flow of described acquisition enters temperature value and specifically comprises:

The force value of detected pressures sensor, described pressure transducer is arranged on describedly to be crossed the entrance of cold heat exchanger and does not cross after low temperature valve described;

Obtain described main flow according to described force value and enter temperature.

4. cross the fault detection method of low temperature valve in supercooling apparatus as claimed in claim 1, it is characterized in that, described basis detects corresponding described main flow at every turn and enters temperature value and described main flow and go out temperature and judged whether low temperature valve occurs extremely specifically to comprise:

Obtain and describedly detect corresponding described main flow and go out temperature value and described main flow and enter difference between temperature value at every turn;

Obtain the degree of deviation according to described difference and preset temperature difference, and the described difference corresponding to every twice detection obtains change degree;

When the described degree of deviation is all greater than predetermined deviation degree threshold value and described change degree is all less than default change degree threshold value, judge that described low temperature valve of crossing occurs abnormal.

5. in the supercooling apparatus as described in claim 1 or 4, cross the fault detection method of low temperature valve, it is characterized in that, when described difference between described first temperature difference and described second temperature difference is less than or equal to predetermined threshold value, judges that described low temperature valve excessively breaks down and specifically comprise:

When difference between described first temperature difference and described second temperature difference is less than or equal to predetermined threshold value, control described cross low temperature valve repeatedly open and close k time, k be more than or equal to 1 integer;

Control described cross low temperature valve open to described first aperture and obtain described first temperature difference, and control described cross low temperature valve open to described second aperture and obtain described second temperature difference; And

When difference between described first temperature difference and described second temperature difference is still less than or equal to described predetermined threshold value, judge that described low temperature valve of crossing breaks down.

6. cross the fault detection method of low temperature valve in supercooling apparatus as claimed in claim 5, it is characterized in that, also comprise:

Show failure message or carry out fault prompting, keeping in repair to point out user.

7. cross the fault detection method of low temperature valve in supercooling apparatus as claimed in claim 5, it is characterized in that, also comprise:

When difference between described first temperature difference and described second temperature difference is greater than described predetermined threshold value, judge that described low temperature valve of crossing recovers normal.

8. cross the fault detection method of low temperature valve in supercooling apparatus as claimed in claim 4, it is characterized in that, the described degree of deviation obtains according to following formula:

d＝|ΔTs-ΔTn _i|/ΔTs，

Wherein, d is the described degree of deviation, and Δ Ts is described preset temperature difference, Δ Tn _ibe detect corresponding described main flow for i-th time to go out temperature value and described main flow and enter difference between temperature value, Δ Tn _i=TOn _i-TIn _i, TOn _idescribed main flow when being i-th detection goes out temperature value, TIn _idescribed main flow when being i-th detection enters temperature value, and wherein i is integer, and 1≤i≤m, m is described preset times.

9. cross the fault detection method of low temperature valve in supercooling apparatus as claimed in claim 4, it is characterized in that, described change degree obtains according to following formula:

c＝|ΔTn _i-ΔTn _j|/ΔTn _i，

Wherein, c is described change degree, Δ Tn _ibe detect corresponding described main flow for i-th time to go out temperature value and described main flow and enter difference between temperature value, Δ Tn _i=TOn _i-TIn _i, TOn _idescribed main flow when being i-th detection goes out temperature value, TIn _idescribed main flow when being i-th detection enters temperature value, Δ Tn _jgo out temperature value and described main flow enter difference between temperature value, Δ Tn for jth time detects corresponding described main flow _j=TOn _j-TIn _j, TOn _jfor described main flow when jth time detects goes out temperature value, TIn _jfor described main flow when jth time detects enters temperature value, wherein i, j are integer, and 1≤i, j≤m, i ≠ j, m is described preset times.

10. cross the fault detection method of low temperature valve in supercooling apparatus as claimed in claim 1, it is characterized in that, described low temperature valve is excessively electric expansion valve.

Cross the failure detector of low temperature valve in 11. 1 kinds of supercooling apparatus, it is characterized in that, comprising:

Detection module, the main flow for being detected cold heat exchanger every Preset Time enters temperature value and main flow goes out temperature value, until detect number of times to reach preset times;

Abnormal judge module, for detecting corresponding described main flow and enter temperature value and described main flow according to each and go out temperature value and judged whether low temperature valve exception occurs;

Control module, for when the generation of described low temperature valve is excessively abnormal, control described low temperature valve of crossing open to the first aperture and obtain the first temperature difference, and control described cross low temperature valve open to the second aperture and obtain the second temperature difference, wherein, described first temperature difference is that described low temperature valve of crossing is opened to go out temperature value and described main flow to main flow described during the first aperture and enter difference between temperature value, and described second temperature difference is that described low temperature valve of crossing is opened to go out temperature value and described main flow to main flow described during the second aperture and enter difference between temperature value;

Judge module, for judging whether the difference between described first temperature difference and described second temperature difference is less than or equal to predetermined threshold value; And

Breakdown judge module, when being less than or equal to predetermined threshold value for the difference between described first temperature difference and described second temperature difference, judges that described low temperature valve of crossing breaks down.

Cross the failure detector of low temperature valve in 12. supercooling apparatus as claimed in claim 11, it is characterized in that, described abnormal judge module comprises:

First acquiring unit, described for obtaining detect corresponding described main flow and goes out temperature value and described main flow and enter difference between temperature value at every turn;

Second acquisition unit, for obtaining the degree of deviation according to described difference and preset temperature difference, and the described difference corresponding to every twice detection obtains change degree;

Abnormal deciding means, for when the described degree of deviation is all greater than predetermined deviation degree threshold value and described change degree is all less than default change degree threshold value, judges that described low temperature valve of crossing occurs abnormal.

Cross the failure detector of low temperature valve in 13. supercooling apparatus as described in claim 11 or 12, it is characterized in that, described breakdown judge module comprises:

First control module, when being less than or equal to predetermined threshold value for the difference between described first temperature difference and described second temperature difference, control described cross low temperature valve repeatedly open and close k time, k be more than or equal to 1 integer;

Second control module, for control described cross low temperature valve open to described first aperture and obtain described first temperature difference, and control described cross low temperature valve open to described second aperture and obtain described second temperature difference; And

Breakdown judge unit, when being still less than or equal to described predetermined threshold value for the difference between described first temperature difference and described second temperature difference, judges that described low temperature valve of crossing breaks down.

Cross the failure detector of low temperature valve in 14. supercooling apparatus as claimed in claim 13, it is characterized in that, also comprise:

Fault cues module, for showing failure message or carrying out fault prompting, keeps in repair to point out user.

The failure detector of low temperature valve is crossed in 15. supercooling apparatus as claimed in claim 13, it is characterized in that, described breakdown judge unit also for, when the difference between described first temperature difference and described second temperature difference is greater than described predetermined threshold value, judge that described low temperature valve of crossing recovers normal.

Cross the failure detector of low temperature valve in 16. supercooling apparatus as claimed in claim 12, it is characterized in that, the described degree of deviation obtains according to following formula:

d＝|ΔTs-ΔTn _i|/ΔTs，

Wherein, d is the described degree of deviation, and Δ Ts is described preset temperature difference, Δ Tn _ibe detect corresponding described main flow for i-th time to go out temperature value and described main flow and enter difference between temperature value, Δ Tn _i=TOn _i-TIn _i, TOn _idescribed main flow when being i-th detection goes out temperature value, TIn _idescribed main flow when being i-th detection enters temperature value, and wherein i is integer, and 1≤i≤m, m is described preset times.

Cross the failure detector of low temperature valve in 17. supercooling apparatus as claimed in claim 12, it is characterized in that, described change degree obtains according to following formula:

c＝|ΔTn _i-ΔTn _j|/ΔTn _i，

Wherein, c is described change degree, Δ Tn _ibe detect corresponding described main flow for i-th time to go out temperature value and described main flow and enter difference between temperature value, Δ Tn _i=TOn _i-TIn _i, TOn _idescribed main flow when being i-th detection goes out temperature value, TIn _idescribed main flow when being i-th detection enters temperature value, Δ Tn _jgo out temperature value and described main flow enter difference between temperature value, Δ Tn for jth time detects corresponding described main flow _j=TOn _j-TIn _j, TOn _jfor described main flow when jth time detects goes out temperature value, TIn _jfor described main flow when jth time detects enters temperature value, wherein i, j are integer, and 1≤i, j≤m, i ≠ j, m is described preset times.

In 18. supercooling apparatus as claimed in claim 11, the failure detector of mistake low temperature valve, is characterized in that, described low temperature valve is excessively electric expansion valve.