Air conditioner and control method therefor

1. An air conditioner comprising:

a main body;

a filter configured to filter impurities externally introduced into the main body;

a fan configured to introduce the impurities into the main body through the filter;

a fan motor configured to drive the fan;

a sensor configured to detect a filter state value for determining a state of the filter, wherein an initial state value of the filter includes a current and a voltage input to the fan motor; and

a processor configured to determine a replacement time for notification of replacing the filter when an impurity purification capacity calculated based on the filter state value detected in real time by the sensor is lower than a reference value,

wherein the reference value is calculated on based on the initial state value of the filter detected by the sensor.

2. The air conditioner of claim 1 , wherein the processor is further configured to:

calculate an initial amount of power consumption of the fan motor based on an initial current and voltage input to the fan motor, and

set an initial impurity purification capacity at a point of time at which a calculated initial amount of power consumption of the fan motor and the initial state value of the filter are detected as an initial setting value of the filter.

3. The air conditioner of claim 2 , wherein:

the impurity purification capacity (Y) is calculated based on Y=Ax 2 +Bx+C,

x represents a change in a current amount of power consumption relative to the initial setting value of the filter,

A represents whether the impurity purification capacity is increased or decreased corresponding to an increase and a decrease of the change in the current amount of power consumption,

B presents an instantaneous change rate of the impurity purification capacity when the change in the current amount of power consumption is 0, and

C represents the impurity purification capacity when the change in the current amount of power consumption is 0.

4. The air conditioner of claim 1 , wherein:

the initial state value of the filter is a wind velocity on an outlet side; and

the processor is further configured to:

calculate an air flow based on the wind velocity on the outlet side, and

set the impurity purification capacity at a point of time at which the calculated air flow and the initial state value of the filter are detected as an initial setting value of the filter.

5. The air conditioner of claim 4 , wherein:

the impurity purification capacity (Y) is calculated based on Y=DE+F,

D represents a ratio of a change in the impurity purification capacity to a change in the air flow,

E represents a current air flow relative to the initial setting value of the filter, and

F represents the impurity purification capacity when the air flow is 0.

6. The air conditioner of claim 1 , wherein:

the initial state value of the filter is a differential pressure before and after the filter on a route to which the impurities are introduced.

7. The air conditioner of claim 6 , wherein the processor is further configured to:

calculate a pressure loss rate based on the differential pressure before and after the filter, and

set the impurity purification capacity at a point of time at which the calculated pressure loss rate and the initial state value of the filter are detected as an initial setting value of the filter.

8. The air conditioner of claim 7 , wherein:

the impurity purification capacity (Y) is calculated based on Y=GH′,

G represents a ratio of a change in an impurity purification capacity logarithm value to a change in a pressure loss rate logarithm value,

H represents a current pressure loss rate relative to the initial setting value of the filter, and

I represents the impurity purification capacity when the pressure loss rate logarithm value is 0.

9. The air conditioner of claim 1 , wherein the processor is further configured to:

before detecting of a current state value of the filter in real time and after setting an initial setting value, determine the reference value by which the impurity purification capacity is reduced from the initial setting value of the filter as the replacement time.

10. A method of controlling an air conditioner, the method comprising:

detecting, by the air conditioner, an initial state value of a filter through a sensor, the initial state value of the filter including a current and a voltage input to a fan motor;

setting an initial setting value of the filter based on the initial state value of the filter detected by the sensor;

detecting a current state value of the filter through the sensor in real time;

checking whether an impurity purification capacity calculated based on the detected current state value of the filter is lower than a reference value; and

outputting a filter replacement notification by determining a replacement time of the filter when the impurity purification capacity is lower than the reference value as a result of the checking,

wherein the reference value is calculated based on the initial state value of the filter detected by the sensor.

11. The method of claim 10 , further comprising, before the detecting of a current state value of the filter in real time and after the setting of an initial setting value, determining the reference value by which the impurity purification capacity is reduced from the initial setting value of the filter as a filter replacement time.

12. The method of claim 11 , wherein:

the impurity purification capacity (Y) is calculated based on Y=Ax 2 +Bx+C,

x represents a change in a current amount of power consumption in comparison to the initial setting value of the filter,

A represents whether the impurity purification capacity is increased or decreased corresponding to an increase and a decrease of the change in the current amount of power consumption,

B presents an instantaneous change rate of the impurity purification capacity when the change in the current amount of power consumption is 0, and

C represents the impurity purification capacity when the change in the current amount of power consumption is 0.

13. The method of claim 11 , wherein the setting of the initial setting value of the filter includes:

calculating an amount of power consumption of the fan motor based on the current and the voltage input to the fan motor; and

setting an initial impurity purification capacity at a point of time at which the initial state value of the filter and the calculated amount of power consumption of the fan motor are detected as the initial setting value of the filter.

14. The method of claim 10 , wherein:

the initial state value of the filter is a wind velocity on an outlet side; and

the setting of the initial setting value of the filter includes:

calculating a wind velocity based on the wind velocity on the outlet side, and

setting an initial impurity purification capacity at a point of time at which the calculated wind velocity and the initial state value of the filter are detected as the initial setting value of the filter.

15. The method of claim 14 , wherein:

the impurity purification capacity (Y) is calculated based on Y=DE+F,

D represents a ratio of a change in the impurity purification capacity to a change in an air flow,

E represents a current air flow relative to the initial setting value of the filter, and

F represents the impurity purification capacity when the air flow is 0.

16. The method of claim 10 , wherein:

the initial state value of the filter is a differential pressure before and after the filter on a route to which impurities are introduced.

17. The method of claim 16 , wherein the setting of the initial setting value of the filter includes:

calculating a pressure loss rate based on the differential pressure before and after the filter; and

setting the impurity purification capacity at a point of time at which the calculated pressure loss rate and the initial state value of the filter are detected as the initial setting value of the filter.

18. The method of claim 17 , wherein:

the impurity purification capacity (Y) is calculated based on Y=GH′,

G represents a ratio of a change in an impurity purification capacity logarithm value to a change in a pressure loss rate logarithm value,

H represents a current pressure loss rate relative to the initial setting value of the filter, and

I represents the impurity purification capacity when the pressure loss rate logarithm value is 0.