JP2007085659A - Controller for air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a comfortable space by preventing dew condensation in an indoor unit without causing significant capacity deterioration during dew condensation preventing operation, and without freezing an indoor heat exchanger. <P>SOLUTION: In the controller for the air conditioner, the dew condensation preventing operation is carried out by reducing rotation of an outdoor fan 36 by an outdoor fan rotational frequency control means 41, and raising an evaporation temperature, such that an outdoor fan rotational frequency becomes a second condensation temperature Tc2 just a predetermined temperature difference ΔT2 higher than a first condensation temperature Tc1, when dew condensation conditions are detected by a dew condensation condition detecting means 39. Capacity deterioration due to rising of the condensation temperature is covered by refrigerant circulation amount increase due to rising of the evaporation temperature. By this, significant capacity deterioration is prevented. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a control device for an air conditioner, and more particularly to a dew prevention control device.

  Conventionally, in a dew prevention control device for an air conditioner, an indoor heat exchanger by restricting an expansion valve while maintaining high performance by changing the control target value of the discharge refrigerant temperature according to the suction humidity of the indoor unit. There was one that prevented dew condensation by reducing the capacity (for example, see Patent Document 1).

Below, the dew prevention control apparatus of the conventional air conditioner is demonstrated. FIG. 11 shows a conventional dew prevention control device for an air conditioner. 4 is a compressor, 5 is an outdoor heat exchanger, 7 is an electric expansion valve, and sequentially connects with one indoor heat exchanger. 17 is an evaporating temperature detecting means for detecting the evaporating temperature of the refrigerant in the indoor heat exchanger 1 during the cooling operation, and 10 is a condensing temperature detecting means for detecting the condensing temperature of the refrigerant in the outdoor heat exchanger 5 during the cooling operation. Yes, receiving the outputs of the evaporating temperature detecting means 17 and the condensing temperature detecting means 10, calculating means 18 for calculating the optimum temperature of the discharged refrigerant temperature which gives the optimum refrigeration effect at that time, and discharging temperature detection for detecting the discharged refrigerant temperature Means 19 and an opening degree control means 20 that receives the output of the discharge temperature detection means 19 and controls the opening degree of the electric expansion valve 7 using the optimum temperature calculated by the calculation means 18 as a control target value of the discharge refrigerant temperature. It is a thing. 21 is a changing means, and when the humidity of the intake air detected by the humidity detecting means 22 becomes higher than a predetermined value, the control target value of the discharge refrigerant temperature is changed to a value higher than the optimum temperature by a constant value. The intake refrigerant temperature that matches the control target value of the refrigerant temperature is also increased, and the opening degree of the electric expansion valve 7 is throttled accordingly, and the superheat degree of the intake refrigerant is controlled to be increased. That is, the refrigerant state on the outlet side of the indoor heat exchanger 1 is maintained on the dry side, the capacity of the indoor heat exchanger 1 is reduced, and dew is prevented.
JP-A-4-98049

  However, in the conventional configuration, since the refrigerant state on the outlet side of the indoor heat exchanger is maintained on the dry side by restricting the expansion valve, the capacity of the indoor heat exchanger is actually significantly reduced and the indoor heat is reduced. Since the exchanger could not be used effectively, the evaporation temperature was lowered and the indoor heat exchanger was frozen.

  The present invention solves the above-described conventional problems, and an object thereof is to provide an air conditioner control device that prevents dew without significantly reducing the cooling performance under dew conditions.

In order to solve the above-described conventional problems, the dew prevention control device of the present invention includes an indoor unit having an indoor heat exchanger and an indoor fan, and an outdoor unit having an outdoor heat exchanger and an outdoor fan. The air conditioner includes a dew condition detection unit, a condensation temperature detection unit, and an outdoor fan rotation speed control unit, and when the dew condition is not detected by the dew condition detection unit, the outdoor fan rotation speed is When the outdoor fan rotation speed control means controls so that the condensation temperature becomes 1 and the dew condition is detected by the dew condition detection means, the outdoor fan rotation speed is more predetermined than the first condensing temperature. The outdoor fan speed control means decelerates and rotates the outdoor fan to increase the evaporation temperature so that the second condensing temperature is increased by the temperature difference of the temperature. Noh By covering the reduction in refrigerant circulation amount increases due to the evaporation temperature rises, so as not to cause significant capacity decrease.

  The dew prevention control device for an air conditioner according to the present invention prevents dew condensation in the indoor unit without causing a significant decrease in capacity during the dew prevention operation, and creates a comfortable space without freezing the indoor heat exchanger. Can be provided.

  1st invention is an air conditioner comprised from the indoor unit which has an indoor heat exchanger and an indoor fan, the outdoor heat exchanger, and the outdoor unit which has an outdoor fan, Dew condition detection means and outdoor heat exchange When the dew condition is not detected by the dew condition detection unit, the outdoor fan rotation number is set to the first condensing temperature. When the dew condition is detected by the dew condition detector and controlled by the fan speed controller, the outdoor fan speed is a second condensing temperature that is higher than the first condensing temperature by a predetermined temperature difference. By rotating the outdoor fan at a reduced speed by the outdoor fan rotation speed control means so as to increase the evaporation temperature, it is possible to prevent dew condensation in the indoor unit without causing a significant decrease in performance during the dew prevention operation, Also indoor heat It is possible to provide a comfortable without freezing the exchanger.

  According to a second aspect of the present invention, there is provided an air conditioner including an indoor unit having an indoor heat exchanger and an indoor fan, an outdoor heat exchanger, and an outdoor unit having an outdoor fan. When the indoor humidity detected by the indoor humidity detecting means is equal to or lower than a predetermined indoor humidity, the outdoor fan rotational speed becomes the first condensing temperature. As described above, when the indoor humidity exceeds a predetermined indoor humidity, the outdoor fan rotational speed is controlled by the outdoor fan rotation speed control means, and the outdoor fan rotation speed is higher by a predetermined temperature difference than the first condensation temperature. By rotating the outdoor fan at a reduced speed by the outdoor fan rotation speed control means so as to reach a temperature, the evaporation temperature is increased, thereby preventing dew condensation in the indoor unit without causing a significant decrease in capacity during the dew prevention operation. Also it is possible to provide a comfortable without freezing the indoor heat exchanger.

  According to a third aspect of the present invention, there is provided an air conditioner including an indoor unit having an indoor heat exchanger and an indoor fan, an outdoor heat exchanger, and an outdoor unit having an outdoor fan. A condensing temperature detection means, an outdoor fan rotation speed control means, and an indoor temperature detection means, and when the indoor temperature detected by the indoor temperature detection means is below a predetermined indoor temperature, or detected by the indoor humidity detection means When the indoor humidity is less than or equal to the predetermined indoor humidity, the outdoor fan rotational speed is controlled by the outdoor fan rotational speed control means so as to be the first condensation temperature, the indoor temperature exceeds the indoor temperature, and the indoor humidity is When the indoor humidity is exceeded, the outdoor fan rotation speed control means decelerates the outdoor fan so that the outdoor fan rotation speed becomes a second condensation temperature higher than the first condensation temperature by a predetermined temperature difference. By increasing the evaporation temperature, it is possible to prevent dew condensation in the indoor unit without causing a significant decrease in capacity during the dew prevention operation and to provide a comfortable space without freezing the indoor heat exchanger. it can.

4th invention is an air conditioner comprised from the indoor unit which has an indoor heat exchanger and an indoor fan, the outdoor heat exchanger, and the outdoor unit which has an outdoor fan, An indoor humidity detection means and an outdoor heat exchanger When the outdoor temperature detected by the outdoor temperature detection means exceeds a predetermined outdoor temperature, or the condensing temperature detection means, the outdoor fan rotation speed control means, the indoor temperature detection means, and the outdoor temperature detection means. When the indoor temperature detected by the indoor temperature detecting means is lower than a predetermined indoor temperature, or when the indoor humidity detected by the indoor humidity detecting means is equal to or lower than the predetermined indoor humidity, the outdoor fan rotational speed is first. When the outdoor temperature is controlled below the predetermined outdoor temperature, the indoor temperature exceeds the predetermined indoor temperature, and the indoor humidity exceeds the predetermined indoor humidity. The outdoor fan rotational speed control means decelerates and rotates the outdoor fan to increase the evaporation temperature so that the outdoor fan rotational speed becomes a second condensing temperature that is higher than the first condensing temperature by a predetermined temperature difference. Thus, it is possible to prevent dew condensation in the indoor unit without causing a significant decrease in performance during the dew prevention operation, and to provide a comfortable space without freezing the indoor heat exchanger.

  5th invention is an air conditioner comprised from the indoor unit which has an indoor heat exchanger and an indoor fan, the outdoor heat exchanger, and the outdoor unit which has an outdoor fan, In an indoor humidity detection means and an outdoor heat exchanger When the indoor humidity detected by the indoor humidity detecting means is equal to or lower than a predetermined indoor humidity, the outdoor fan rotational speed becomes the first condensing temperature. When the indoor humidity detected by the indoor humidity detecting means exceeds a predetermined indoor humidity, the outdoor fan rotational speed is set to be higher than the first condensing temperature. The outdoor fan rotational speed control means decelerates and rotates the outdoor fan to increase the evaporation temperature so that the second condensing temperature is increased by a temperature difference of a predetermined temperature, and the indoor humidity detected by the indoor humidity detecting means is a predetermined room. When the other predetermined indoor humidity higher than the humidity is exceeded, the outdoor fan rotational speed control is performed so that the outdoor fan rotational speed becomes a third condensing temperature higher by a predetermined temperature difference than the first condensing temperature. By rotating the outdoor fan at a reduced speed by means to increase the evaporation temperature, it is possible to prevent dew condensation in the indoor unit without causing a significant decrease in capacity during the dew prevention operation, and without freezing the indoor heat exchanger. A comfortable space can be provided.

(Embodiment 1)
FIG. 1 is a schematic diagram of the air conditioner according to the first embodiment, and FIG. 2 is a flowchart of the dew prevention operation of the air conditioner according to the first embodiment. In FIG. 1, an indoor unit 33 having an indoor heat exchanger 31 and an indoor fan 32 includes a compressor 34, an outdoor heat exchanger 35, an outdoor fan 36, and an outdoor unit 38 having a pressure reducing device 37. It is connected in a ring. The indoor unit 33 has dew condition detection means 39, and the outdoor unit 38 has condensation temperature detection means 40 and outdoor fan rotation speed control means 41. The operation of the control device for a harmonic machine configured as described above will be described below.

  The high-pressure gas refrigerant discharged from the compressor 34 is liquefied by exchanging heat with the outdoor fan 36 in the outdoor heat exchanger 35, depressurized by the decompression device 37, and then sent to the indoor unit 33. In the indoor unit 33, heat is exchanged by the indoor fan 32 in the indoor heat exchanger 31, and the low pressure gas is converted into the compressor 34 again. At this time, since the outdoor fan rotation speed control means 41 controls the outdoor fan rotation speed to keep the temperature of the outdoor heat exchanger 35 at a predetermined condensation temperature, a comfortable air conditioning state is always maintained. When the humidity of the indoor unit rises due to a load change and becomes a dew condition, the dew prevention operation is performed. The detailed operation will be described with reference to the flowchart of the dew operation in FIG.

  In STEP 1 which is normally operated, as shown in STEP 2, the outdoor fan rotation speed is controlled to keep the first condensing temperature Tc 1 constant. If the dew condition detecting unit 39 detects the dew condition in STEP 3, the outdoor fan speed is controlled so that the second condensing temperature Tc2 is higher than the first condensing temperature by a predetermined temperature difference ΔT2 in STEP 4. Thus, the evaporation temperature is kept high. In STEP5, the exposure condition detection means 39 detects the avoidance of the exposure condition. If the avoidance of the exposure condition is detected, the process returns to STEP2 which is the normal operation, and if the avoidance of the exposure condition is not detected, the process returns to STEP4. By repeating the above cycle, it is possible to prevent dew condensation in the indoor unit without causing a significant decrease in capacity during dew prevention operation, provide a comfortable space without freezing the indoor heat exchanger, and load fluctuations It is possible to provide an air conditioner that can cope with an overload condition caused by the above.

(Embodiment 2)
FIG. 3 is a schematic diagram of the air conditioner according to the second embodiment, and FIG. 4 is a flowchart of the dew prevention operation of the air conditioner according to the second embodiment. Note that those already described in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  In FIG. 3, the indoor unit 33 has an indoor humidity detecting means 42, and starts the dew prevention operation when the indoor humidity h exceeds a predetermined indoor humidity h1. This is the same as the first embodiment.

(Embodiment 3)
FIG. 5 is a schematic diagram of the air conditioner in the third embodiment, and FIG. 6 is a flowchart of the dew prevention operation of the air conditioner in the third embodiment. Note that those already described in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  In FIG. 5, the indoor unit 33 includes an indoor temperature detection unit 43, the indoor humidity h detected by the indoor humidity detection unit 43 exceeds a predetermined indoor humidity h <b> 1, and the indoor temperature Tin detected by the indoor temperature detection unit 44. When the temperature is lower than the predetermined indoor temperature Tin1, the dew prevention operation is started, and the operation after the start is the same as in the first embodiment.

(Embodiment 4)
FIG. 7 is a schematic diagram of the air conditioner according to the fourth embodiment, and FIG. 8 is a flowchart of the dew prevention operation of the air conditioner according to the fourth embodiment. Note that those already described in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  In FIG. 7, the outdoor unit 38 has an outdoor temperature detecting means 44, the indoor humidity h detected by the indoor humidity detecting means 43 exceeds a predetermined indoor humidity h1, and the indoor temperature Tin detected by the indoor temperature detecting means 44. When the outdoor temperature Tout detected by the outdoor temperature detecting means 45 is less than the predetermined outdoor temperature Tout1, the dew prevention operation is started. This is the same as Form 1.

(Embodiment 5)
FIG. 9 is a flowchart at the time of dew prevention operation of the air conditioner according to the fifth embodiment. In STEP 1 that is operating normally, as shown in STEP 2, the outdoor fan rotation speed increases or decreases so as to keep the first condensing temperature Tc 1 constant. In step 3, the indoor humidity h is detected. In STEP 4, it is determined whether the indoor humidity h is higher than the predetermined indoor humidity h2. If the indoor humidity h is higher than the predetermined indoor humidity h2, the process proceeds to STEP 5, otherwise. Proceed to STEP 8.

  In STEP5, the evaporating temperature is kept high by increasing or decreasing the outdoor fan rotation speed so that the third condensing temperature Tc3 is higher than the first condensing temperature Tc1 by a predetermined temperature difference ΔT3. In STEP 6, the indoor humidity h is detected again. In STEP 7, it is determined whether the indoor humidity h is equal to or lower than the predetermined indoor humidity h2. If the indoor humidity h is equal to or lower than the predetermined indoor humidity h2, the process proceeds to STEP 11. Return to STEP5.

  In STEP 8, it is determined whether or not the indoor humidity h is higher than a predetermined indoor humidity h3 set lower than the indoor humidity h2. If the indoor humidity h is higher than the predetermined indoor humidity h3, the process proceeds to STEP 9, and if not, STEP3. Return to.

  In STEP 9, the evaporating temperature is kept high by increasing or decreasing the outdoor fan rotation speed so that the fourth condensing temperature Tc4 is higher than the first condensing temperature Tc1 by a predetermined temperature temperature difference ΔT4. In STEP 10, the indoor humidity h is detected again. In STEP 11, it is determined whether or not the indoor humidity h is equal to or lower than the predetermined indoor humidity h3. If the indoor humidity h is equal to or lower than the predetermined indoor humidity h3, the process returns to STEP 2, otherwise. Return to STEP9.

  By repeating the above cycle, it is possible to prevent dew condensation in the indoor unit without causing a significant decrease in capacity during dew prevention operation, provide a comfortable space without freezing the indoor heat exchanger, and load fluctuations It is possible to provide an air conditioner that can cope with an overload condition caused by the above.

  The air conditioner control device of the present invention can provide an air conditioner control device that prevents dew without significantly reducing the cooling performance under the dew conditions, so that only the separation type air conditioner can be provided. It can also be applied to an integrated air conditioner.

The schematic diagram of the air conditioner in Embodiment 1 of this invention The flowchart of the dew prevention operation of the air conditioner in Embodiment 1 of this invention. The schematic diagram of the air conditioner in Embodiment 2 of this invention Flowchart of dew prevention operation of air conditioner in Embodiment 2 of the present invention The schematic diagram of the air conditioner in Embodiment 3 of this invention Flowchart of dew prevention operation of air conditioner in Embodiment 3 of the present invention The schematic diagram of the air conditioner in Embodiment 4 of this invention Flowchart of dew prevention operation of air conditioner in Embodiment 4 of the present invention Flowchart of dew prevention operation of air conditioner in Embodiment 5 of the present invention Schematic diagram of a conventional air conditioner

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,31 Indoor heat exchanger 32 Indoor fan 33 Indoor unit 4,34 Compressor 5,35 Outdoor heat exchanger 36 Outdoor fan 7,37 Pressure reducing device 38 Outdoor unit 39 Dew condition detection means 10, 40 Condensation temperature detection means 41 Outdoor fan rotation speed control means 42 Indoor humidity detection means 43 Indoor temperature detection means 44 Outdoor temperature detection means 17 Evaporation temperature detection means 18 Calculation means 19 Discharge temperature detection means 20 Opening control means 21 Change means Tc Condensing temperature Tc1 First condensation temperature Tc2 Second condensation temperature Tc3 Third condensation temperature Tc4 Fourth condensation temperature h Indoor humidity h1, h2 Predetermined indoor humidity Tin Indoor temperature Tin1 Predetermined indoor temperature Tout Outdoor temperature Tout1 Predetermined outdoor temperature ΔT2, ΔT3, ΔT4 Predetermined Temperature difference

Claims (5)

In an air conditioner composed of an indoor unit having an indoor heat exchanger and an indoor fan, an outdoor heat exchanger and an outdoor unit having an outdoor fan, the dew condition detection means and the condensation temperature detection of the outdoor heat exchanger And the outdoor fan rotation speed control means, and when the dew condition is not detected by the dew condition detection means, the outdoor fan rotation speed control means so that the outdoor fan rotation speed becomes the first condensing temperature. And when the dew condition is detected by the dew condition detector, the outdoor fan speed is set to a second condensing temperature that is higher than the first condensing temperature by a predetermined temperature difference. A control device for an air conditioner, characterized in that the outdoor fan is decelerated and rotated by an outdoor fan rotation speed control means to raise the evaporation temperature. In an air conditioner composed of an indoor unit having an indoor heat exchanger and an indoor fan, an outdoor heat exchanger and an outdoor unit having an outdoor fan, an indoor humidity detecting means and a condensation temperature detecting means of the outdoor heat exchanger And the outdoor fan rotation speed control means, and when the indoor humidity detected by the indoor humidity detection means is equal to or lower than a predetermined indoor humidity, the outdoor fan rotation speed is set to the first condensing temperature. When the indoor humidity exceeds the predetermined indoor humidity as controlled by the rotational speed control means, the outdoor fan rotational speed becomes a second condensing temperature that is higher by a predetermined temperature difference than the first condensing temperature. A control device for an air conditioner characterized in that the outdoor fan rotation speed control means decelerates and rotates the outdoor fan to raise the evaporation temperature. In an air conditioner composed of an indoor unit having an indoor heat exchanger and an indoor fan, an outdoor heat exchanger and an outdoor unit having an outdoor fan, an indoor humidity detecting means and a condensation temperature detecting means of the outdoor heat exchanger And an outdoor fan rotation speed control means and an indoor temperature detection means, and when the indoor temperature detected by the indoor temperature detection means is equal to or lower than a predetermined indoor temperature, or the indoor humidity detected by the indoor humidity detection means When the humidity is lower than the predetermined indoor humidity, the outdoor fan rotation speed is controlled by the outdoor fan rotation speed control means so as to become the first condensation temperature, the indoor temperature exceeds the predetermined indoor temperature, and the indoor humidity is When the predetermined indoor humidity is exceeded, the outdoor fan rotational speed control means adjusts the outdoor fan rotational speed to a second condensing temperature that is higher than the first condensing temperature by a predetermined temperature difference. Serial control device for an air conditioner characterized by the outdoor fan rotates at a reduced speed to increase the evaporation temperature. In an air conditioner composed of an indoor unit having an indoor heat exchanger and an indoor fan, an outdoor heat exchanger and an outdoor unit having an outdoor fan, an indoor humidity detecting means and a condensation temperature detecting means of the outdoor heat exchanger An outdoor fan rotation speed control means, an indoor temperature detection means, and an outdoor temperature detection means, and the outdoor temperature detected by the outdoor temperature detection means exceeds a predetermined outdoor temperature, or the indoor temperature detection means When the indoor temperature detected at the temperature is lower than the predetermined indoor temperature, or when the indoor humidity detected by the indoor humidity detecting means is equal to or lower than the predetermined indoor humidity, the outdoor fan rotation speed is set to the first condensing temperature. The outdoor fan speed control means controls the outdoor temperature to be equal to or lower than the predetermined outdoor temperature, the indoor temperature exceeds the predetermined indoor temperature, and the indoor humidity is the predetermined indoor humidity. When the outdoor fan rotation speed is exceeded, the outdoor fan rotation speed control means decelerates and rotates the outdoor fan so that the outdoor fan rotation speed becomes a second condensation temperature that is higher than the first condensation temperature by a predetermined temperature difference. A control device for an air conditioner, characterized by raising an evaporation temperature. In an air conditioner composed of an indoor unit having an indoor heat exchanger and an indoor fan, an outdoor heat exchanger and an outdoor unit having an outdoor fan, an indoor humidity detecting means and a condensation temperature detecting means of the outdoor heat exchanger And the outdoor fan rotation speed control means, and when the indoor humidity detected by the indoor humidity detection means is equal to or lower than a predetermined indoor humidity, the outdoor fan rotation speed is set to the first condensing temperature. When the indoor humidity exceeds the predetermined indoor humidity controlled by the rotational speed control means, the outdoor fan rotational speed is a second higher than the first condensing temperature by a predetermined temperature difference.
When the outdoor fan is decelerated and rotated by the outdoor fan rotation speed control means to increase the evaporation temperature so as to reach the condensation temperature, and the indoor humidity exceeds another predetermined indoor humidity higher than the predetermined indoor humidity The outdoor fan rotational speed control means decelerates and rotates the outdoor fan to increase the evaporation temperature so that the outdoor fan rotational speed becomes a third condensing temperature that is higher than the first condensing temperature by a predetermined temperature difference. A control device for an air conditioner characterized in that