Disclosure of Invention
In order to solve the above problems in the prior art, that is, to solve the problem of false defrosting of the existing air conditioner under outdoor low temperature conditions, the present invention provides a defrosting control method of an air conditioner, wherein the control method comprises:
collecting outdoor environment parameters and/or operating parameters of an air conditioner outdoor unit;
judging whether the air conditioner meets basic defrosting conditions or not according to the outdoor environment parameters and/or the operation parameters;
when the basic defrosting condition is met, comparing the current fluctuation rate of the outdoor fan with a first set threshold value;
and selectively starting the defrosting mode according to the comparison result.
In the preferred technical solution of the defrosting control method of the air conditioner, the step of "acquiring the outdoor environment parameters and/or the operation parameters of the outdoor unit of the air conditioner" specifically includes: the outdoor ambient temperature and the outdoor unit coil temperature are collected.
In a preferred embodiment of the defrosting control method of an air conditioner, the step of comparing the current fluctuation rate of the outdoor fan with a first predetermined threshold value includes:
judging the temperature interval of the outdoor environment temperature;
determining the first set threshold according to the temperature interval;
calculating the current fluctuation rate;
and comparing the current fluctuation rate with a first set threshold value.
In a preferred embodiment of the defrosting control method for an air conditioner, the first set threshold is decreased as the temperature range decreases.
In a preferred technical solution of the defrosting control method of the air conditioner, the step of "acquiring an outdoor environment parameter and/or an operation parameter of an outdoor unit of the air conditioner" further includes: and acquiring the running time of the air conditioner after the last defrosting.
In a preferred embodiment of the defrosting control method for an air conditioner, the step of "calculating the current fluctuation rate" includes: the current fluctuation ratio is calculated according to the following formula:
m=it/io
wherein m is the current fluctuation rate; i is describedtThe average value of the sampling current of the outdoor fan in the first set time period before the calculation is obtained; i is describedoThe average value of the sampling current of the outdoor fan in the second set time period after the last defrosting or the stable operation of the starting is obtained.
In a preferred technical solution of the defrosting control method of the air conditioner, the sampling method is AD sampling.
In a preferred embodiment of the defrosting control method of the air conditioner, the step of selectively turning on the defrosting mode according to the comparison result specifically includes:
and when the current fluctuation rate is greater than or equal to the first set threshold value, controlling the air conditioner to start a defrosting mode.
In a preferred embodiment of the defrosting control method of the air conditioner, the step of "selectively turning on the defrosting mode according to the comparison result" further includes:
when the current fluctuation rate is smaller than the first set threshold, further judging whether the current fluctuation rate is smaller than or equal to a second set threshold;
and selectively controlling the air conditioner to start the defrosting mode according to the comparison result.
In a preferred embodiment of the above defrosting control method for an air conditioner, the step of selectively controlling the air conditioner to turn on the defrosting mode according to the comparison result specifically includes: and when the current fluctuation rate is less than or equal to the second set threshold value, controlling the air conditioner to enter a defrosting mode.
As can be understood by those skilled in the art, in a preferred embodiment of the present invention, the control method includes: collecting outdoor environment parameters and/or operating parameters of an air conditioner outdoor unit; judging whether the air conditioner meets basic defrosting conditions or not according to the outdoor environment parameters and/or the operation parameters; when the basic defrosting condition is met, comparing the current fluctuation rate of the outdoor fan with a first set threshold value; and selectively starting the defrosting mode according to the comparison result.
The invention adds the condition of judging the current fluctuation rate of the outdoor fan and the first set threshold value on the basis of the basic defrosting condition, judges whether the air conditioner really needs defrosting or not according to the current fluctuation rate of the outdoor fan, avoids the problem of false defrosting such as no defrosting or no defrosting with frost and the like caused by the basic defrosting condition, avoids the waste of resources and simultaneously improves the use experience of users. Specifically, when the current fluctuation rate of the outdoor fan is greater than the first set threshold, it is proved that the frost formation amount of the outdoor unit is increased at this time, the power of the fan is increased, and thus the current value fluctuation is large, and at this time, the defrosting mode is started, so that the outdoor unit can be effectively defrosted. When the current fluctuation rate of the outdoor unit is smaller than a first set threshold value, the fact that the outdoor unit does not frost or slightly frosts at the moment is proved, the operation of the air conditioner is not influenced enough, at the moment, although the basic frosting condition is met, the defrosting is probably false defrosting at the moment, therefore, the defrosting mode is not started at the moment, the energy is effectively saved, and the user experience is improved. That is to say, the defrosting control method of the air conditioner solves the problem of false defrosting of the existing air conditioner under the outdoor low-temperature condition, the control steps are simple and effective, the method can be realized by utilizing the existing detection element in the air conditioner or only adding a simple detection element, the cost is hardly influenced, and the method is suitable for batch production.
Detailed Description
Preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only for explaining the technical principle of the present invention, and are not intended to limit the scope of the present invention. For example, the second set threshold may be set to 0.95, or may be selected within a range smaller than 1 according to actual conditions, for example, 0.96, 0.97, 0.94, or the like.
First, referring to fig. 1, a defrosting control method of an air conditioner according to the present invention will be described. Fig. 1 is a schematic flowchart of a defrosting control method of an air conditioner according to the present invention.
As shown in fig. 1, in order to solve the problem of false defrosting of the existing air conditioner under outdoor low temperature conditions, the invention provides a defrosting control method of an air conditioner, which mainly comprises the following steps:
s100, collecting outdoor environment parameters and/or operation parameters of an outdoor unit of an air conditioner, for example, collecting outdoor environment parameters or operation parameters of the outdoor unit according to basic defrosting conditions or simultaneously collecting the outdoor environment parameters and the operation parameters of the outdoor unit, wherein the outdoor unit environment parameters comprise outdoor environment temperature, the outdoor unit operation parameters comprise outdoor unit coil temperature and operation time data (such as duration of temperature data and/or operation time after last defrosting), of course, those skilled in the art can also collect corresponding parameters according to other basic defrosting conditions, for example, when the defrosting control method of the difference between the evaporating temperature and the atmospheric temperature is adopted, acquiring the ambient temperature and the evaporating temperature, specifically, acquiring the pressure of a refrigerant at the outlet of the evaporator to be approximately used as the evaporating pressure, and calculating or looking up a table to obtain the evaporating temperature;
s200, judging whether the air conditioner meets basic defrosting conditions or not according to the outdoor environment parameters and/or the operation parameters of the outdoor unit of the air conditioner, for example, judging whether the duration time of outdoor environment temperature, outdoor unit coil temperature and temperature data simultaneously meets the basic defrosting conditions of the air conditioner or not after the parameters are collected;
s300, comparing the current fluctuation rate of the outdoor fan with a first set threshold value when the basic defrosting condition is met; for example, after the basic defrosting condition is met, acquiring the current value of the outdoor fan in the corresponding time period according to the running time data (the running time after the last defrosting), calculating the current fluctuation rate, and comparing the current fluctuation rate with the first set threshold value;
s400, selectively starting a defrosting mode according to the comparison result, for example, when the current fluctuation rate is greater than or equal to a first set threshold value, starting the defrosting mode; and when the current fluctuation rate is smaller than a first set threshold value, the defrosting mode is not started.
In the scheme, whether the air conditioner meets basic defrosting conditions is judged firstly, then the relation between the current fluctuation rate and the first set threshold and the second set threshold is judged, and finally the defrosting mode is selectively started according to the judgment result.
The defrosting control method of the air conditioner according to the present invention will be described in detail with reference to fig. 1 and 2. Fig. 2 is a flowchart for comparing the current fluctuation rate of the outdoor fan with a first set threshold in the method of the present invention.
As shown in fig. 1 and fig. 2, in a preferred embodiment, step S200 specifically includes:
and judging whether the air conditioner meets the basic defrosting condition or not according to the outdoor environment temperature, the outdoor unit coil temperature and the duration time of the temperature data. For example, it is determined whether the above parameters satisfy the following conditions:
1)Taonot less than 4 ℃ and TdefAt ≦ 6 ℃ for 5 minutes;
2)-6℃≦Taot at < 4 DEG Cdef≦0.8Tao8.5 and last 5 minutes;
3)-15℃≦Taot at less than-6 DEG CdefAt ≦ (5 × Tao-72)/7/1.08 for 5 min;
4)Taot at < -15 DEG CdefAt ≦ 20 ℃ for 5 minutes;
wherein, TaoIs the outdoor ambient temperature; t isdefThe outdoor unit coil temperature.
When any one of the above 4 conditions is satisfied, it is determined that the outdoor unit satisfies the basic defrosting condition.
Of course, the above-described defrosting conditions are merely exemplary, and naturally, the defrosting conditions are different for different air conditioners. For example, two temperature sensors may be provided in the outdoor unit coil, and when one or both of the two temperatures detected by the two temperature sensors is lower than the corresponding set temperature on the premise that the outdoor environment temperature satisfies the condition, it is determined that the basic defrosting condition is satisfied.
Referring to fig. 2, after determining that the air conditioner satisfies the basic defrosting condition, in one possible embodiment, step S300 specifically includes:
s310, judging a temperature interval in which the outdoor environment temperature is located, for example, judging a set temperature interval in which the temperature is located according to the previously acquired environment temperature, wherein the temperature interval can be divided into three intervals of (-infinity, -10), [ -10, -5) and [ -5, 10);
s320, determining a first set threshold according to the temperature interval;
in step S320, as the frost formation amount of the outdoor fan increases, the power of the outdoor fan increases, and thus the current value gradually increases. Therefore, when defrosting is required, the value of the current fluctuation rate is greater than 1, and therefore, the first set threshold is at least 1. Further, since the change in current is smaller as the frost formation is smaller with a decrease in temperature, the first set threshold is smaller, and thus different temperature ranges correspond to different first set thresholds, and the first set threshold decreases as the temperature ranges decrease. For example, in one possible arrangement:
10℃>Taothe first set threshold value is 1.08 when the temperature is not less than-5 ℃;
-5℃>Taothe first set threshold value is 1.06 when the temperature is ≧ 10 ℃;
Tao-10 ℃ below zero, the first set threshold is 1.04;
the values of the temperature interval and the current fluctuation rate are only exemplary, and those skilled in the art can make different temperature ranges and select other current fluctuation rates according to the type and model of the air conditioner and the difference of the geographic environment. For example, in the south, the air humidity is relatively high in winter, the frosting amount of the air conditioner is relatively large, and therefore the first set threshold value can be increased, for example, 10 ℃ is higher than TaoThe first set threshold value was 1.1 ≧ 5 ℃.
S330, calculating the current fluctuation rate;
in a more preferred embodiment, the current ripple ratio can be calculated according to the following equation (1):
m=it/io (1)
in the formula (1), m is the current fluctuation rate; i.e. itThe average value of the sampling current of the outdoor fan in the first set time period before the calculation is obtained; i.e. ioAnd the average value of the sampling current of the outdoor fan in the second set time period after the last defrosting operation or the starting operation. Specifically, the firstThe time period and the second time period are preferably 3 minutes, itThe average value of the sampling current of the outdoor fan within 3 minutes before the calculation is calculated ioThe average value of the sampling current can be calculated by timing 3 minutes after defrosting is finished and operating the indoor air supply fan and the outdoor air supply fan. The skilled person can select different first time period and second time period according to different types and models of air conditioners, for example, the first time period and the second time period are respectively 2 minutes or 4 minutes, etc. The sampling method is preferably AD sampling, but other sampling methods such as interval sampling may be adopted. In addition, when the current average value is calculated, the maximum value and the minimum value in the sampling can be removed, so that the calculation accuracy of the current average value is ensured.
S340, comparing the current fluctuation rate with the first set threshold, for example, comparing the calculated current fluctuation rate with the first set threshold determined in S320.
After comparing the current fluctuation rate with the first set threshold, in a possible implementation, step S400 specifically includes: and selectively starting the defrosting mode according to the comparison result. E.g., 10 ℃ TaoThe defrosting mode is started when the temperature is not less than-5 ℃ and m is not less than 1.08; -5 ℃ TaoThe defrosting mode is started when the temperature is larger than or equal to-10 ℃ and m is larger than or equal to 1.06; t isaoWhen the temperature is lower than-10 ℃, and m is larger than or equal to 1.04, the defrosting mode is started.
Further, in a more preferred embodiment, when the current fluctuation rate is less than the first set threshold, the defrosting control method of the air conditioner further includes:
and further judging the current fluctuation rate and a second set threshold value, and selectively controlling the air conditioner to start the defrosting mode according to the comparison result, for example, when the current fluctuation rate is greater than the second set threshold value, defrosting is not performed, and when the current fluctuation rate is less than or equal to the second set threshold value, the defrosting mode is started. Wherein the second set threshold is less than 1, preferably 0.95. If the current fluctuation rate is in a decreasing trend, the situation that the outdoor fan is in failure to operate and the operation is not smooth is indicated, at the moment, the current fluctuation rate is not needed to be used for judging the frosting condition of the outdoor unit, and defrosting is directly carried out according to the basic frosting condition. The second set threshold may be selected within a range smaller than 1 according to actual conditions, and may be, for example, 0.96, 0.97, 0.94, or the like.
In the invention, the steps can be eliminated, and under the condition of eliminating the steps, the invention can also be realized, so that the problem of frost-free defrosting in the prior art is solved.
In summary, the above preferred embodiments have the advantages that: the outdoor environment temperature is divided into a plurality of ranges, different first set thresholds are set in different ranges, the fact that the current change trend of the outdoor fan is different along with the change of the temperature is fully considered, the accuracy of current fluctuation rate judgment conditions is guaranteed, and the defrosting accuracy of the control method is improved. The current fluctuation rate is compared with the two set thresholds, so that the fluctuation range of the current fluctuation rate is refined, the accuracy of judgment by using the current fluctuation rate is improved, and the problem of inaccurate judgment caused by comparison with one set threshold is avoided. In addition, in the control method, the invention can be realized by using the existing detection element in the air conditioner or only adding a simple detection element, has little influence on the cost and is suitable for mass production.
The operation of the defrosting control method of the air conditioner according to the present invention will be briefly described with reference to fig. 3. Fig. 3 is a logic diagram of a defrosting control method of an air conditioner according to the present invention.
As shown in fig. 3, in a possible control logic, the outdoor environment temperature and the outdoor unit coil temperature are collected → whether the basic defrosting condition is satisfied is judged, if so, the next step is performed, otherwise, the current value is returned to be collected → the AD sampling current value is returned, the current fluctuation ratio m → judgment m > 1.08 is satisfied, if so, the defrosting mode is started, otherwise, the next step → judgment m <0.95 is satisfied, if so, the defrosting mode is started, otherwise, the basic defrosting condition is again collected.
So far, the technical solutions of the present invention have been described in connection with the preferred embodiments shown in the drawings, but it is easily understood by those skilled in the art that the scope of the present invention is obviously not limited to these specific embodiments. Equivalent changes or substitutions of related technical features can be made by those skilled in the art without departing from the principle of the invention, and the technical scheme after the changes or substitutions can fall into the protection scope of the invention.