KR100381178B1 - A power saving control method of air conditioner - Google Patents

Abstract

The present invention relates to a power saving control method of an air conditioner for controlling the compressor operation frequency of the air conditioner using the inverter circuit,

Calculate the standard operating current value for each operating frequency according to the indoor / outdoor temperature difference, and adjust the operating frequency up / down one step at the current operating frequency to reduce the power consumption by comparing the current operating current value with the standard operating current value when the compressor is operated at a specific operating frequency. By doing so, it is possible to prevent overcooling through efficient compressor operation control, thereby improving comfort, and providing an effect of significantly reducing power consumption.

Description

A power saving control method of air conditioner

The present invention relates to a power saving control method of an air conditioner for controlling the compressor operation frequency of the air conditioner using an inverter circuit, and in particular, the standard operating current value for each standard operating frequency under various indoor and outdoor temperature conditions is calculated and The present invention relates to a power saving control method of an air conditioner that performs efficient control while reducing power consumption by performing frequency control by comparing a standard operating current value with a current operating current value.

In general, an air conditioner is installed for the purpose of air-conditioning or purifying the air with a heater, an air conditioner, an air purifier, etc., to create a more comfortable indoor environment. Such an air conditioner is a machine for the purpose of air conditioning in a room, and there are many models for indoor air conditioning and heating, and additionally have functions such as dehumidification and cleanliness.

The air conditioner is roughly provided with an indoor and outdoor heat exchanger and a refrigeration system consisting of a capillary tube, a four-way valve, a compressor, and a condenser. The compressor is a device for compressing a refrigerant, and the rotation speed is determined by the frequency of a power source applied to the compressor. do.

In the above, if the frequency of the power applied to the compressor can be changed, the rotation speed of the compressor can be changed, so that the refrigerant flow rate can be freely controlled to directly control the capability of the air conditioner itself. A compressor capable of changing the frequency of the compressor by changing the frequency as described above is called an inverter compressor.

Accordingly, the inverter compressor is capable of controlling the air conditioner's ability by changing the number of revolutions by changing the feed voltage or frequency. The inverter compressor takes a short time to reach the set temperature by rotating at a high speed. The continuous change of the number reduces the change in the room temperature and reduces the chance of power loss, improving the efficiency.The frost, which is attached to the outdoor heat exchanger during the heating operation and degrades the heating capacity, is removed in a short time by rotating the compressor at high speed. The heating operation can be efficiently performed, and the starting current is reduced by rotating the compressor at low speed during starting.

1 is a schematic configuration diagram of an air conditioner according to the prior art.

The conventional air conditioner for air conditioning is installed on the indoor side as shown in FIG. 1 to operate as an evaporator when cooling and to operate as a condenser when heating, and to be installed on the outdoor side when cooling An outdoor heat exchanger (2) operating as a condenser and an evaporator during heating, a compressor (3) for sucking and discharging gas refrigerant of low temperature and low pressure into a gas refrigerant of high temperature and high pressure, and an expansion mechanism for adjusting the flow pressure of the refrigerant (4), a pipe (5) connecting the indoor heat exchanger (1) and the outdoor heat exchanger (2), the compressor (3), the expansion mechanism (4), and the operating frequency of the compressor (3) to vary. The inverter circuit 6 is comprised.

In particular, it is possible to perform operation control by changing the cooling capability from high output to low output using the inverter circuit 6 which is not possible in the on / off air conditioner.

The various operating frequencies of the compressor 3 in the inverter circuit 6 set the operating frequency by the difference between the current room temperature and the set temperature. Therefore, in the case of cooling, the inverter circuit 6 allows the compressor 3 to be operated at the maximum operating frequency when the difference between the room temperature and the set temperature becomes 2.0 ° C or more.

That is, if the room temperature and the set temperature is 2.0 ℃ or more to operate at the cooling maximum operating frequency, if less than 2.0 ℃ to operate by reducing the operating frequency little by little.

In this way, the room temperature control corresponds to the indoor load by setting the operating frequency of the compressor 3 as the difference between the room temperature and the set temperature by increasing the operating frequency of the compressor 3 when the room temperature is high or the user desires a low temperature. Do it.

For example, in the condition that the outdoor temperature is 35 ℃, the initial indoor temperature is 33 ℃, as shown in Figure 2, the set temperature is 25 ℃, as shown in (a) at 27 ℃ or more as the maximum operating frequency (Fmax) , At 26 ° C. is operated as the cooling energetic force (Fc), and at 25 ° C. or lower, the operation is performed at the minimum operating frequency (F min). By the way, when the set temperature is 20 ℃, as shown in (b) is operated at Fmax at 22 ℃ or more, Fc at 21 ℃, Fmin below 20 ℃.

In the above operation, when operating the compressor 3 at the maximum operating frequency, regardless of the room temperature, if the set temperature is low, it can be operated at a high frequency, and when operating at a high frequency compared to the low room temperature, supercooling may occur and become inefficient operation. There is a high probability problem.

In addition, the air conditioner using the inverter circuit 6 has a high cooling capacity (Kcal / h) / power consumption (W) in the low frequency operating range of the compressor 3, which helps to save power, but at high frequency. In the operating range, the comfort due to the fast cooling ability is increased, but there is a problem in that it does not help power saving because the EER is lowered.

In addition, the conventional air conditioner has a high possibility that the power consumption increases due to bad installation position of the outdoor unit or overfilling of the refrigerant, and the control itself becomes quite complicated to measure and judge all the above factors by the sensor. There is also.

The present invention has been made to solve the above-mentioned problems of the prior art, the purpose of which is to calculate the standard operating current value for each operating frequency according to the indoor and outdoor temperature difference, comparing the current operating current value and the standard operating current value when operating the compressor at a specific operating frequency By controlling the operating frequency so that the power consumption is reduced, it is possible to prevent overcooling through efficient compressor operation control, thereby improving comfort, and to provide a power saving control method of an air conditioner that can increase power saving effect. .

1 is a block diagram showing the configuration of a typical refrigeration cycle,

2 is a view showing the operating frequency control of the compressor for each set temperature according to the prior art,

3 is a flowchart illustrating a power saving control method of an air conditioner according to the present invention;

4 and 5 are diagrams showing the results of the cooling capacity / power consumption test at the cooling low frequency and the lowest frequency, respectively,

6 is a view showing the operating frequency control of the compressor by the set temperature when the outdoor temperature is 35 ℃, the initial indoor temperature is 33 ℃ according to the present invention,

7 is a view showing the operation frequency control of the compressor for each set temperature when the outdoor temperature 30 ℃, the initial indoor temperature is 28 ℃ according to the present invention.

According to a feature of the power saving control method of the air conditioner according to the present invention for solving the above problems, the first step of determining the standard frequency for each indoor and outdoor temperature and calculating the standard operating current value according to each standard frequency, by the user The second step of determining the operation of the compressor by measuring the indoor and outdoor temperature when setting the power-saving operation, and using the indoor and outdoor temperature measured in the second step to read the test standard frequency and the standard operating current value and the test standard frequency for a certain time And a fourth step of measuring a current operating current value when the test standard frequency is operated and comparing the standard operating current value with each other, and a step by step at the test standard frequency according to the comparison result of the fourth step. And a fifth step of performing frequency control or determining a final operating frequency.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a flowchart illustrating a power saving control method of an air conditioner according to the present invention. Referring to this, first, in the first step, a standard operating frequency and a standard operating current value for each standard operating frequency in a standardized indoor / outdoor temperature condition are calculated. (See S1).

4 and 5, the cooling rating Fc and the minimum frequency Fmin are set as operating frequency conditions, and the outdoor temperature is set to 35 ° C. and the room temperature is 27 ° C. as the standard cooling condition. Experimental table showing the experiment is shown.

4 and 5, as the indoor temperature is lowered without changing the outdoor temperature, the cooling capacity is remarkably lowered, the power consumption is gradually increased, and eventually, the EER is also lowered. Through this, it is confirmed that the driving efficiency is largely caused by the indoor and outdoor temperature difference and the operating frequency, and the standard operating frequency and the standard operating current value are calculated.

For example, assuming that the cooling standard condition is the summer temperature in Korea, the power consumption is 812.7W / h, the operating current is about 3.7A for Fc, and the power consumption is 478W / h, and the current value is 2.2A for Fmin.

Therefore, when the outdoor temperature is 35 ℃, the standard current value of Fc is set to 3.6 ~ 3.8A, and for Fmin, the standard current value is set to 2.1 ~ 2.3A, and these standard current values are set according to the change of the outdoor temperature, the indoor temperature, and the operating frequency. do.

At this time, the coil is mounted on one power line to which power is supplied from the indoor unit to the outdoor unit. The outdoor microcomputer measures the current value of the electric power flowing to the outdoor unit through the coil, and informs the indoor unit of the current value through communication.

Next, in the second step, when the user turns on the air conditioner and selects the power saving operation, the indoor and outdoor temperature (Ti, To) is measured (see S2). In the third step, the indoor temperature and the set temperature are different. It is determined whether the compressor is operated. If the determination result is no, the process returns to the second step S2 (see S3).

However, when the determination result of the third step S3 is YES, in the fourth step, the test standard frequency Kl 및 and the standard current value Bm by Ti-To are determined. Read from S1) (see S4).

Then, in the fifth step, the compressor is operated at the test standard frequency of the fourth step S4, and in the sixth step, it is checked whether the test time is completed (see S5 and S6).

If the check result of the sixth step (S6) is no, go to the fifth step (S5) to continue to operate the shaft, but if the check result is 'yes' for the test in the seventh step The current value An is measured at the standard frequency (see S7).

In this case, the eighth step compares whether the standard operating current value read in the fourth step S4 and the current current value measured in the seventh step S7 are similar to each other. The standard operating frequency for the test is determined as the final operating frequency. (Refer to S8 and S9.) However, when the comparison result of the eighth step S8 is no, in the tenth step, the current current value is the standard operating current value. The greater is compared (see S10).

When the comparison result of the tenth step (S10) is 'Yes', the first step frequency is lowered from the standard operating frequency for the test so that the current value decreases in the eleventh step, and the comparison result of the tenth step In case of No, the first step frequency is increased from the standard operating frequency for the test in step 12 (see S11 and S12).

Thereafter, in the thirteenth step, it is determined whether the frequency control time has ended, and when the determination result is YES, the frequency changed in the eleventh step S11 or the twelfth step S12 in step 14 is used for testing. After setting the standard operating frequency and reading the standard operating current value, the compressor is operated for a predetermined time, and then the flow goes to the seventh step S7 to perform the current value comparison and the frequency control / determination operation (see S13 and S14).

However, when the determination result of the thirteenth step S13 is no, in the fifteenth step, it is monitored whether the outdoor temperature is changed from the initial measured value according to the change of the external environment. While going to step S2, subsequent steps S3 to S14 are performed, whereas when the outdoor temperature is not changed, the process returns to step 14 (S14).

For example, when the user turns on the air conditioner and selects a power saving operation, the present invention allows the user to move to the set frequency after operating at rated speed for several minutes to stabilize the cycle.

As shown in (a) of FIG. 6, when the outdoor temperature is 35 ° C., the initial indoor temperature is 33 ° C., and the set temperature is 25 ° C., operating at the set frequency causes the indoor temperature to decrease little by little. The current value is monitored.

As the temperature continuously decreases, the operating current increases while the compressor operates at the set frequency. As shown in FIG. 6 (b), when the set temperature is 20 ° C, the indoor unit responds to the maximum frequency from the initial room temperature of 33 ° C. Therefore, when the room temperature decreases, the operating current value increases from the initial stage, so the operating frequency is lowered to prevent the current value rising.

At this time, since the current value setting of the frequency for the indoor temperature is changed according to the outdoor temperature, in FIG. 7, when the outdoor temperature is 30 ° C. and the initial indoor temperature is 28 ° C., the set temperature is set to 25 ° C./20° C. The current value is shown.

Power saving control method of the air conditioner of the present invention configured as described above is to calculate the standard operating current value for each operating frequency according to the indoor and outdoor temperature difference, the current power consumption by comparing the current operating current value and the standard operating current value when the compressor operation at a specific operating frequency By increasing and decreasing the operation frequency by one step at the current operating frequency to be less, it is possible to prevent overcooling through efficient compressor operation control, thereby improving comfort and reducing power consumption.

Claims (5)

A first step of determining a standard frequency for each indoor / outdoor temperature and calculating a standard operating current value according to each standard frequency; and a second step of determining whether the compressor is operated by measuring an indoor / outdoor temperature when the power saving operation is set by the user; A third step of reading the test standard frequency and the standard operating current value using the indoor and outdoor temperature measured in step 2 and driving at the test standard frequency for a predetermined time; and measuring the current operating current value when operating at the test standard frequency. A fourth step of comparing the standard operating current with each other, and a fifth step of performing step-by-step frequency control at the test standard frequency or determining a final operating frequency according to the comparison result of the fourth step. How to control the power saving of the unit The method of claim 1, In the fifth step, when the current operating current value is greater than the standard operating current value, the first stage frequency is lowered from the test standard frequency, and when the current operating current value is smaller than the standard operating current value, the first stage frequency is increased. And when the current operating current value is about the standard operating current value, determining a test standard frequency as a final operating frequency. The method of claim 1, In the fifth step, after performing the step-by-step frequency control, the changed frequency is updated to the test standard frequency, and the standard operation current value is read and the current value comparison and the frequency control / determination operation are performed. Control method. The method of claim 1, In the second step, the environmental condition of the air conditioner is continuously monitored by changing the outdoor temperature according to the change of the external environment, and updating the test standard frequency and the standard operating current due to the indoor and outdoor temperature difference according to the monitoring result. Control method. The method of claim 1, In the power saving control method of the air conditioner, an air conditioner comprising: mounting a coil on a power line supplied with electric power from an indoor unit to an outdoor unit, measuring a current value of electric power flowing through the coil to the outdoor unit, and transmitting the current value to the indoor unit; How to control power saving.