JPH0914724A - Operation control device of air conditioner - Google Patents

Abstract

PURPOSE: To eliminate a 'stuffiness' or the like and to enable a comfortable air conditioning to be carried out by a method wherein a sufficient humidity control can be performed when a cooling operation is performed. CONSTITUTION: A volume variable compressor, an outdoor heat exchanger, an electrical expansion valve and an indoor heat exchanger having an air volume variable indoor fan are connected in sequence so as to constitute a refrigerant circuit in which a cooling operation can be performed. Then, a volume of the compressor and an air volume of an indoor fan are controlled in such a way that a detected temperature of a room temperature sensor (Th-r) may become a set temperature. In addition, as a temperature difference in respect to a set temperature of an indoor temperature detected by the room temperature sensor (Th-r) reaches a predetermined value, a desired sensible heat capability is held in such a way that a sensed humidity of a humidity sensor (Hu-r) may reaches a target humidity and then a volume of the indoor fan is reduced and a latent heat capability is increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner operation controller, and more particularly to a humidity control measure.

[0002]

2. Description of the Related Art Conventionally, Japanese Patent Publication No.
As disclosed in Japanese Unexamined Patent Publication No. 20339, there is a device having a dehumidifying operation function. When the dehumidifying operation is started, the air conditioner sets the indoor fan to a light wind state, and at the same time, repeats the operation and stop of the compressor to duty-control the evaporation of the refrigerant in the indoor heat exchanger to dehumidify the room. There is.

[0003]

In the above air conditioner, the capacity of the compressor is not controlled because the capacity is not controlled by the inverter or the like, and although the dehumidifying operation is performed, the cooling is intermittently performed. I'm just driving,
There is a problem that comfortable air conditioning operation is not performed due to the limitation of dehumidification.

On the other hand, in recent years, the compressor and the indoor fan are inverter-controlled to control the capacity of the compressor and the air volume of the indoor fan in multiple stages to improve the accuracy of the cooling operation. In this conventional cooling operation, since the relationship between the sensible heat capacity and the latent heat capacity is constant, that is, the sensible heat ratio (SHF) is controlled to be constant, as the capacity of the compressor is increased, the air volume of the indoor fan is increased. The air volume of the indoor fan also decreases as the compressor capacity decreases.

Therefore, for example, at the start of the cooling operation, since the amount of heat stored in the room is large, the compressor is operated at a high capacity and the indoor fan is operated at a high air volume. That is, when the compressor and the indoor fan are controlled by the inverter, the frequency of the compressor is set to a high frequency and the rotation speed of the indoor fan is set to a high rotation speed.

After that, when the cooling load decreases, the frequency of the compressor is lowered and the rotation speed of the indoor fan is lowered. Then, the frequency of the compressor and the rotation speed of the indoor fan are maintained in a state of being balanced with the sensible heat load.

However, in the above-mentioned control, although the user is in a comfortable state with respect to "hot and cold feeling",
Due to the lack of latent heat capacity, the humidity is high and you will feel "humid heat". In this case, conventionally, the set temperature of the dry-bulb temperature, that is, the set room temperature is reduced to remove "humidity".

However, in this case, since the set room temperature is lowered, the state becomes "too cold" and the cooling operation is performed in the state of "slightly cold and cold feeling". For this reason, there is a problem that the air conditioning is bad for the body and the comfortable air conditioning is not performed.

Further, the dehumidifying operation which has been generally performed conventionally is almost the same as the cooling operation condition in which the sensible heat load and the latent heat load are low, the compressor is operated at a low frequency, and the rotation speed of the indoor fan is decreased. The rotation speed is set. As a result, although the sensible heat capacity is low, the latent heat capacity is also low, so it is not possible to reliably eliminate "steam heat", and if the latent heat capacity is increased, the sensible heat capacity also rises. There was a problem that it was inferior in comfort due to the "slightly cold and warm feeling" dehumidification operation.

The present invention has been made in view of the above problems, and an object of the present invention is to enable sufficient humidity control during cooling operation to eliminate "steam and heat" and to provide comfortable air conditioning. It is what

[0011]

In order to achieve the above object, the means taken by the present invention is to change the latent heat capacity without lowering the sensible heat capacity.

Concretely, as shown in FIG. 1, the means taken by the invention according to claim 1 is as follows.
1), the heat source side heat exchanger (23), the expansion mechanism (24),
A refrigerant circuit (11) capable of performing at least cooling operation is provided by being sequentially connected to a usage-side heat exchanger (31) including a usage-side fan (3F) with variable air volume. Then, the room temperature detecting means (Th-r) for detecting the room temperature, and the room temperature detecting means (Th-r)
-r) The above compressor (2
Room temperature control means (51) for controlling the capacity of 1) and the air volume of the use side fan (3F) is provided. Further, humidity detecting means (Th-h) for detecting indoor humidity is provided. In addition, when the temperature difference between the room temperature detected by the room temperature detection means (Th-r) and the set temperature reaches a predetermined value, the humidity detected by the humidity detection means (Hu-r) is replaced by the room temperature control means (51). Humidity control means (52) is provided to change the latent heat capacity so that the target humidity becomes the target humidity.

Further, the means taken by the invention according to claim 2 is, in place of the humidity detecting means (Th-h) and the humidity controlling means (52) of the invention according to claim 1, first, the utilization side heat exchanger. (31)
Evaporation temperature detection means (Th-e) for detecting the evaporation temperature of the refrigerant is provided. In addition, room temperature detection means (Th
-r) when the temperature difference between the detected room temperature and the set temperature reaches a specified value, instead of the room temperature control means (51), the latent temperature is changed so that the temperature detected by the evaporation temperature detection means (Th-e) becomes the target temperature. Humidity control means (52) for changing the capacity is provided.

Further, the means taken by the invention according to claim 3 is the invention according to claim 1 or 2, wherein the humidity control means (52) maintains a predetermined sensible heat capacity to increase the latent heat capacity. It is configured as follows.

Further, the means taken by the invention according to claim 4 is the invention according to claim 3, wherein the humidity control means (52) increases the capacity of the compressor (21) at the same time.
It is configured to increase the latent heat capacity by lowering the air volume of the user side fan (3F).

[0016] According to a fifth aspect of the invention, in the first or second aspect of the invention, the humidity control means (52) maintains a predetermined sensible heat capacity to reduce the latent heat capacity. It is configured as follows.

Further, the means taken by the invention according to claim 6 is the invention according to claim 5, wherein the humidity control means (52) reduces the capacity of the compressor (21) at the same time.
It is configured to reduce the latent heat capacity by increasing the air volume of the user side fan (3F).

Further, in the means of the invention according to claim 7, in the invention of claim 2, the evaporation temperature detecting means (Th-e) determines the intermediate refrigerant temperature in the utilization side heat exchanger (31). It is provided in the utilization side heat exchanger (31) so as to be detected.

[0019]

According to the first aspect of the present invention,
First, in the cooling operation, the room temperature control means (51) gives priority to control of the room temperature, and the compressor (21) is controlled based on the set temperature.
And the air volume of the fan (3F) on the use side are controlled to predetermined values. Then, it is determined whether or not the room temperature detected by the room temperature detecting means (Th-r) has reached the set temperature, the normal cooling operation is executed until the set temperature is reached, and the capacity of the compressor (21) and the use side The air volume of the fan (3F) is controlled to a specified value.

After that, when the room temperature becomes almost the set temperature, the humidity control means (52) controls the latent heat capacity, and whether the room humidity detected by the humidity detection means (Hu-r) is the target humidity or not. To judge. In the invention according to claim 2, it is determined whether the detected temperature detected by the evaporation temperature detecting means (Th-e) is the target temperature. Specifically, in the invention according to claim 7, the evaporation temperature detecting means (Th-e) detects the intermediate refrigerant temperature of the intermediate portion of the refrigerant pipe in the utilization side heat exchanger (31), and this intermediate refrigerant temperature is the target. Determine whether it is temperature.

In the inventions according to claims 3 and 4, when the indoor humidity is high, the capacity of the compressor (21) and the air volume of the use side fan (3F) are calculated, and the use side fan (3F) is calculated.
To reduce the heat exchange capacity of the utilization side heat exchanger (31), and increase the capacity of the compressor (21) to reduce the low pressure. As a result, the latent heat capacity is increased while the latent heat capacity is increased, and the dehumidification capacity is increased.
Increase the amount of water removed.

In the inventions according to claims 5 and 6, when the indoor humidity is low, the capacity of the compressor (21) and the air volume of the user side fan (3F) are calculated, and the user side fan (3F) is calculated. To increase the heat exchange capacity of the utilization side heat exchanger (31), and further reduce the capacity of the compressor (21),
Increase low pressure. As a result, the latent heat capacity is reduced while the sensible heat capacity is maintained, the dehumidification capacity is reduced, and the amount of water to be removed is reduced.

[0023]

Therefore, according to the first aspect of the present invention,
When the temperature difference between the room temperature Tri and the set temperature Trset reaches a predetermined value, the latent heat capacity is increased or decreased so that the detected humidity RH becomes the target humidity RH-T. Therefore, it is possible to control the humidity while removing the sensible heat load. As a result, it is possible to improve comfort.

Further, in the inventions according to claims 3 and 4, since the latent heat capacity is increased when the indoor humidity is high, it is possible to surely dehumidify the room and eliminate the "humid heat". In particular, while maintaining a predetermined sensible heat capacity and increasing the capacity of the compressor (21), the fan (3F) on the use side
Since the amount of airflow is decreased to increase the latent heat capacity, it is possible to prevent the room temperature from decreasing and avoid the "too cold" state. As a result, good air conditioning can be performed on the body, and comfort can be improved.

Further, in the invention according to claim 2, since the detected evaporation temperature of the evaporation temperature detecting means (Th-e) is used, it is not necessary to provide the humidity detecting means (Hu-r), and the increase in the number of parts is prevented. can do. That is, since the detected evaporation temperature of the evaporation temperature detecting means (Th-e) can be used for controlling other actuators, the detecting means can be shared, and the structure can be simplified. .

Further, in the inventions according to claims 5 and 6, since the latent heat capacity is lowered when the indoor humidity is low, dehumidification in the room can be reduced and "overdrying" can be avoided. In particular, it maintains the prescribed sensible heat capacity and reduces the capacity of the compressor (21), and at the same time, the fan (3F) on the user side
Since the amount of airflow is increased to reduce the latent heat capacity, it is possible to prevent the room temperature from decreasing and avoid the "overdry" condition.

Furthermore, since the input reduction due to the capacity decrease of the compressor (21) is large compared to the input increase due to the increase in the air volume of the user side fan (3F), it is possible to reduce the power consumption and the power consumption. Can save money.

[0028]

Embodiments of the present invention will be described below in detail with reference to the drawings.

<First Embodiment> -Structure of First Embodiment-As shown in FIG. 2, the air conditioner (1
0) is configured as a so-called separate type, and one indoor unit (3) with respect to one outdoor unit (20).
0) are connected to form one refrigerant circuit (11).

The outdoor unit (20) includes a variable capacity compressor (21) and a four-way switching valve (22) which is switched during a cooling operation cycle as indicated by a solid line in the figure and during a heating operation cycle as indicated by a broken line in the figure. And an outdoor heat exchanger (23) that is a heat source side heat exchanger that functions as a condenser during cooling operation and as an evaporator during heating operation, and an electric expansion valve (24) that constitutes an expansion mechanism for decompressing the refrigerant. And are provided.

In the compressor (21), the frequency of the compressor motor (CM) is variably adjusted by an inverter so that the compressor capacity is variable. Further, the outdoor heat exchanger (23) has an outdoor fan (2F) which is a heat source side fan.
The outdoor fan (2F) is configured such that the rotation speed of the external fan motor (FM-O) is variably adjusted by an inverter so that the air volume is variable.

On the other hand, the indoor unit (30) is provided with an indoor heat exchanger (31) which is a utilization side heat exchanger that functions as an evaporator during cooling operation and as a condenser during heating operation. The indoor heat exchanger (31) is provided with an indoor fan (3F) that is a use side fan, and the indoor fan (3F)
Is configured such that the rotation speed of the inner fan motor (FM-I) is variably adjusted by an inverter and the air volume is variable.

The compressor (21), the four-way switching valve (22), the outdoor heat exchanger (23), the electric expansion valve (24) and the indoor heat exchanger (31) are arranged in this order in the refrigerant pipe (12). Are connected by a refrigerant circuit (11), and the refrigerant circuit (11) is
A closed circuit capable of reversible operation is formed by switching the four-way switching valve (22) between a cooling operation cycle and a heating operation cycle so that heat is transferred by circulating the refrigerant.

FIG. 3 shows a main part of the electric control system (40) in the air conditioner (10), and an AC power source (41).
AC power is supplied from the power converter to the power converter (42), and the AC power is converted to predetermined control power by the power converter (42). Furthermore, the control power is supplied to, for example, a frequency control unit (43) and a rotation speed control unit (44) each including an inverter circuit, and the frequency control unit (43) and the rotation speed control unit (4) are supplied.
Driving power is supplied from 4) to the compressor motor of the compressor (21) and the inner fan motor (FM-I) of the indoor fan (3F). Although not shown, drive power is also supplied to the outdoor fan motor (FM-O) of the outdoor fan (2F) from the power conversion unit (42) through the rotation speed control unit as with the indoor fan (3F). There is.

Further, the power conversion section (42), the frequency control section (43) and the rotation speed control section (44) receive a control signal from the CPU (50), and the frequency control section (43) causes the compressor motor to operate. (CM) frequency control to control the capacity of the compressor (21), while the rotation speed control section (44) controls the rotation speed of the inner fan motor (FM-I) to control the air volume of the indoor fan (3F). Are in control.

Further, the CPU (50) detects a room temperature sensor (Th-r) which is a room temperature detecting means for detecting the room temperature Tri in the room in which the indoor unit (30) is installed, and the room humidity RH. The humidity sensor (Hu-r), which is the humidity detection means, is connected, and the compressor rotation speed sensor (Th-p) that detects the rotation speed of the compressor (21) and the rotation speed of the indoor fan (3F) Is connected to a fan rotation speed sensor (Th-f). The CPU (50) is a room temperature sensor (Th-
r) detection temperature Tri and humidity sensor (Hu-r) detection humidity RH
The capacity of the compressor (21) and the air volume of the indoor fan (3F) are controlled based on the detected rotation speed of each rotation speed sensor (Th-p, Th-f), and the electric expansion valve (24) is controlled. The opening and the air volume of the outdoor fan (2F) are controlled.

The CPU (50) is provided with a room temperature control means (51) and a humidity control means (52) as a feature of the present invention. The room temperature control means (51) controls the capacity of the compressor (21) and the air volume of the user side fan (3F) so that the detected temperature Tri of the room temperature sensor (Th-r) becomes the set temperature Trset. . Specifically, the room temperature sensor (Th-r) outputs a frequency signal and a rotation speed signal to the frequency control unit (43) and the rotation speed control unit (44) to output the frequency of the compressor (21) (compressor). (21) capacity) and the rotation speed of the indoor fan (3F) (air volume of the indoor fan (3F)) are controlled.

When the temperature difference between the room temperature Tri detected by the room temperature sensor (Th-r) and the set temperature Trset reaches a predetermined value, the humidity control means (52) replaces the room temperature control means (51) with the humidity sensor ( The latent heat capacity is increased so that the detected humidity RH of Hu-r) becomes the target humidity (comfort humidity) RH-T. That is, the humidity control means (52) increases the frequency of the compressor (21) while maintaining a predetermined sensible heat capacity, and at the same time,
It is configured to reduce the rotation speed of the indoor fan (3F), increase the latent heat capacity, and increase the dehumidification capacity.

-Principle of controlling latent heat capacity- Therefore, the basic principle of increasing the latent heat capacity of the humidity control means (52) will be described.

FIG. 4 shows the relationship between the sensible heat capacity and the latent heat capacity with respect to changes in the frequency of the compressor (21) and the air volume of the indoor fan (3F). In FIG. 4, when the frequency of the compressor (21) is increased from H1 to H5 while keeping the air volume of the indoor fan (3F) constant, the sensible and latent heat capacities change along the broken lines A1 to A5, that is, the As the heat capacity increases, so does the latent heat capacity. On the other hand, with the frequency of the compressor (21) kept constant, the air volume of the indoor fan (3F) changes from A1 to A5.
If it increases to, the sensible heat capacity and the latent heat capacity change along the solid lines H1 to H5, and the sensible heat capacity increases as the latent heat capacity decreases. Conversely, the air volume of the indoor fan (3F) increases. When it decreases, the latent heat capacity increases as the sensible heat capacity decreases.

In the conventional cooling operation, since the sensible heat ratio (SHF) is controlled to be constant, the sensible heat capacity and the latent heat capacity correspond to each other. When the cooling operation is started from the state point SP-1, the compression is performed. The machine (21) is operated at high frequency and the indoor fan (3F) is operated at high air volume (high rotation speed). After that, as the cooling load decreases, the state transitions to SP-2 and SP-3, and the compressor (2
The frequency of 1) and the air volume of the indoor fan (3F) are reduced, and the sensible heat capacity and latent heat capacity change substantially linearly along the state line C1 in FIG.

On the other hand, the change lines L1, L2, L3 in FIG.
It shows the cooling load of the room to be air-conditioned, and the change line
L1 indicates the cooling load of the room of the wooden house, change line L2 indicates the cooling load of the room of the condominium, and change line L3 indicates the cooling load of the room of the airtight house. These cooling loads shift to the right side in FIG. 3 when the outside air rises (in the daytime) and the sunshine amount and the indoor / outdoor temperature difference increase, and shift to the left side in FIG. 3 with time in the early morning and at night. In this way, the sensible heat load is
The latent heat load remains constant, although it varies with the time of day. The reason for this is that the latent heat load is theoretically a constant value because it is determined by the ventilation volume and the indoor heat generation such as the number of people in the room.

Therefore, in the conventional cooling operation, since the amount of heat retained is large at the beginning of the operation, the state point becomes SP-1, and the compressor (21) is operated at high frequency and the indoor fan (3F) is operated at high air volume. However, at the state point SP-3 where the cooling load and the cooling capacity are balanced, only the amount of heat entering is processed, and the compressor (21)
Is operated at low frequency and the indoor fan (3F) is operated at low air volume. As a result, for example, in the room L1 of the wooden house, the latent heat capacity becomes insufficient, and "steam and heat" is felt.

Therefore, the present inventor, as described above, increases the frequency of the compressor (21) while keeping the air volume of the indoor fan (3F) constant, while the latent heat capacity increases as the sensible heat capacity increases. The present invention has been made by focusing on the fact that when the frequency of the compressor (21) is kept constant and the air volume of the indoor fan (3F) is reduced, the latent heat capacity increases as the sensible heat capacity decreases. That is, when the sensible heat load decreases, the compressor (21)
At the same time as increasing the frequency of, the number of rotations of the indoor fan (3F) is reduced, the latent heat capacity is increased and the dehumidification capacity is increased.

More specifically, when the rotation speed of the indoor fan (3F) is reduced, the heat exchange capacity of the indoor heat exchanger (31) is reduced, so that the low pressure on the suction side of the compressor (21) is reduced. , Specifically, indoor heat exchangers that are evaporators (31)
That is, the refrigerant pressure is reduced. In addition, the compressor (2
Since the capacity which is the frequency of 1) is increased, the low pressure decreases, the dew point temperature of the refrigerant pipe surface in the indoor heat exchanger (31) decreases, and the amount of condensed water increases.

FIG. 5 shows the relationship between the frequency of the compressor (21) shown in FIG. 4 and the air volume of the indoor fan (3F). When the sensible heat is 1000 W, the change in latent heat capacity is It is shown that the air volume of the indoor fan (3F) decreases as the frequency of 21) increases. From this, when the frequency corresponding to the predetermined latent heat capacity is determined, the air volume of the indoor fan (3F), that is, the rotation speed of the indoor fan (3F) is determined.

On the contrary, when the frequency of the compressor (21) is lowered and the rotation speed of the indoor fan (3F) is increased at the same time,
The latent heat capacity decreases and the dehumidification capacity decreases, that is, excessive dehumidification is prevented. Based on the above principle, the latent heat capacity is increased or decreased.

-Air conditioning operation- Next, the operation of the air conditioning apparatus (10) in the cooling operation and the heating operation will be described.

First, during the cooling operation cycle of the refrigerant circuit (11), the high-pressure refrigerant discharged from the compressor (21) is condensed and liquefied in the outdoor heat exchanger (23), and this liquid refrigerant is After the pressure is reduced by the electric expansion valve (24), the vapor is evaporated in the indoor heat exchanger and returns to the compressor (21) for circulation. On the other hand, during the heating operation cycle, the high-pressure refrigerant discharged from the compressor (21) is condensed and liquefied in the indoor heat exchanger (31), and this liquid refrigerant is decompressed by the electric expansion valve (24). After that, circulation is performed by evaporating in the outdoor heat exchanger (23) and returning to the compressor (21).

-Control Operation- Next, the control operation of the compressor (21) and the like during the cooling operation will be described. 6 shows the detailed control operation,
FIG. 7 shows a conceptual operation.

First, the operation of the basic concept of the present control will be described with reference to FIG. 7. In the cooling operation control of the present embodiment, the control of the room temperature Tri is given priority, and in step ST21, It is determined whether the room temperature Tri is stable. That is, the room temperature control means (51) executes the normal cooling operation until the room temperature Tri reaches the set temperature Trset. After that, when the indoor temperature Tri becomes stable, the routine proceeds to step ST22, where the indoor humidity RH is the target humidity RH-T.
Is determined. When the indoor humidity RH is high, the process proceeds to step ST23, and the humidity control means (52)
Calculates the frequency of the compressor (21) and the rotation speed of the indoor fan (3F), and then proceeds to step ST24 to output the frequency signal and the rotation speed signal for dehumidification.

Next, the detailed control operation will be described with reference to FIG. First, when the cooling operation is started, the set temperature Trset of the room temperature is input to the CPU (50) in step ST1. Subsequently, in step ST2, the room temperature control means (51) of the CPU (50) outputs the frequency signal of the compressor (21) to the frequency control section (43) based on the set temperature Trset, and the compressor (21). The frequency is controlled and the capacity is controlled to a predetermined value.

Further, the above steps ST2 to ST3
Then, it is determined whether the room temperature Tri detected by the room temperature sensor (Th-r) has become lower than the set temperature Trset. Since the present indoor temperature Tri is higher than the set temperature Trset, that is, the cooling load is large and the sensible heat load is high, the determination in step ST3 is NO
Moving to ST4, the detection signal of the room temperature sensor (Th-r) will be fetched.

After that, the process proceeds to step ST2, and the room temperature control means (51) controls the frequency signal of the compressor (21) based on the detected room temperature Tri and the set temperature Trset to the frequency control section (4).
Output to 3) and control the frequency of the compressor (21). At that time, in response to the capacity control of the compressor (21), the indoor fan (3
It also controls the air volume of F). Then, the operation of steps ST2 to ST4 is repeated to execute the cooling operation, and the steps ST2 to ST4 constitute a room temperature control loop.

That is, the room temperature control means (51) executes the normal cooling operation, and gives priority to the room temperature control, and
As indicated by the state line C2 in (1), first, the cooling load is removed.
Specifically, as shown in Table 1 below, the compressor (21) is kept at a high frequency and the indoor fan (3F) until the indoor temperature Tri reaches the set temperature Trset, that is, until the indoor temperature Tri stabilizes. After making the air flow rate high, the frequency of the compressor (21) and the air flow of the indoor fan (3F) are sequentially decreased as the cooling load is decreased, and both the sensible heat capacity and the latent heat capacity are proportionally decreased. When the indoor temperature Tri rises, the frequency of the compressor (21) and the air volume of the indoor fan (3F) are both proportionally increased to proportionally increase both the sensible heat capacity and the latent heat capacity. The increase / decrease operation will be repeated.

[0056]

[Table 1]

After that, when the room temperature Tri becomes lower than the set temperature Trset, the determination in step ST3 becomes YES, the room temperature control loop is exited, and the process proceeds to step ST11 to proceed to the humidity control loop. That is, at the state point SP-4 in FIG. 8, the frequency of the compressor (21) and the air volume of the indoor fan (3F) are balanced corresponding to the sensible heat load.

Subsequently, in step ST11, the humidity control means (52) executes the humidity control, that is, the indoor humidity RH detected by the humidity sensor (Hu-r) is fetched. Then, the process proceeds from step ST11 to step ST12, and it is determined whether or not the current indoor humidity RH is the target humidity RH-T stored in the memory in advance. Specifically, the humidity difference ΔRH between the indoor humidity RH and the target humidity RH-T (ΔRH =
RH-RH-T) is less than 5%.

If the humidity difference ΔRH is within 5%, the determination in step ST12 is YES and step ST1
3, the current operating state is maintained, specifically, the current frequency of the compressor (21) and the current air volume of the indoor fan (3F) are maintained, and the process returns to step ST4 to repeat the above operation. .

On the other hand, when the humidity difference ΔRH is 5% or more, the determination in step ST12 is NO and the step is
Moving to ST14, the current frequency of the compressor (21) and the air volume of the indoor fan (3F) will be corrected. That is, for example, the current frequency of the compressor (21) and the indoor fan (3F)
When the indoor air humidity RH is higher than the target humidity RH-T in the case where the air flow rate is the state point SP-4 in FIG. 8, the occupant is in a state of feeling "humid and hot".

Therefore, the humidity control means (52) increases the frequency of the compressor (21) and at the same time lowers the rotation speed of the indoor fan (3F) to set it to the state point SP-5 in FIG. , The sensible heat capacity is maintained as it is, the latent heat capacity is increased, and the dehumidification capacity is increased. This point is the most characteristic point of the present invention, as indicated by the solid arrow in the humidity control in Table 1 above, and in the normal cooling operation, the frequency of the compressor (21) and the indoor fan (3F). Instead of reducing the air volume proportionally, the rotation speed of the indoor fan (3F) is reduced to reduce the heat exchange capacity of the indoor heat exchanger (31), and then the compressor (21). Increase the frequency of
The low pressure is reduced to increase the amount of condensed water.

Then, as the correction of the compressor (21), for example, a constant Ch is added to the current frequency output Comp.out and a new frequency output Comp.out (Comp.out = Comp.out +
Ch) and proportional control (P control). In addition, as a correction for the indoor fan (3F), proportional control (P control) is performed as with the compressor (21), and the frequency output Comp.o of the compressor (21) is used.
Multiply ut by a constant (-11) and add a constant (1100) to obtain a new rotation speed Fan.out (rpm) (Fan.out (rpm) =
-11 x Comp.out + 1100).

Thereafter, the steps from step ST14
Returning to ST4, the above operation is repeated, and steps ST11 to ST14 constitute a humidity control loop. This humidity control loop does not perform only dehumidification as described above, but performs dehumidification while performing the cooling operation, that is, dehumidification is performed by increasing the latent heat capacity while removing the sensible heat load. .

-Effects of Embodiment 1- As described above, according to this embodiment, when the temperature difference between the room temperature Tri and the set temperature Trset reaches a predetermined value, the detected humidity RH.
Since the latent heat capacity is increased to reach the target humidity RH-T, dehumidification in the room can be reliably performed, and "humid heat"
Can be resolved.

Furthermore, the predetermined sensible heat capacity is maintained and the capacity of the compressor (21) is increased, and at the same time, the air volume of the indoor fan (3F) is decreased to increase the latent heat capacity, so that the indoor temperature is prevented from decreasing. It is possible to avoid the "too cold" condition. As a result, good air conditioning can be performed on the body, and comfort can be improved.

Specifically, as shown in the psychrometric chart of FIG.
When the indoor air condition is indicated by a ● mark, conventionally, the sensible heat capacity and the latent heat capacity are dehumidified at a constant ratio (constant sensible heat ratio SHF), so that the user feels “steamy heat” and changes the set room temperature. In order to lower the temperature, the air state marked with ◎ was in the "too cold" state, whereas in this embodiment the latent heat capacity was increased while keeping the sensible heat capacity constant, so the air condition was marked with ○. It is possible to eliminate only "steam and heat".

<Embodiment 2> -Structure of Embodiment 2 In this embodiment, as shown by the chain line in FIG. 3, instead of the humidity detecting means (Hu-r) in Embodiment 1, evaporation temperature detecting means is used. The heat exchange sensor (Th-e) is used.

The heat exchange sensor (Th-e) is configured to detect the evaporation temperature of the refrigerant in the indoor heat exchanger (31). Specifically, as shown in FIGS. 10 and 11,
The indoor heat exchanger (31) is configured such that a large number of fins (3b, 3b, ...) Are attached to the refrigerant pipe (3a), and the heat exchange sensor (Th-e) is a refrigerant in the refrigerant pipe (3a). It is attached to an intermediate portion between the inlet side and the outlet side of to detect the intermediate refrigerant temperature.

On the other hand, when the temperature difference between the room temperature detected by the room temperature sensor (Th-r) and the set temperature reaches a predetermined value, the humidity control means (52) replaces the room temperature control means (51) with the heat exchange sensor. The latent heat capacity is increased so that the detected heat exchange temperature ET of (Th-e) becomes the target temperature ET-T.

Therefore, the reason why the indoor humidity can be controlled by the heat exchange temperature ET will be described. In the psychrometric chart shown in FIG. 12, for example, the state of air in the room is the state point S
, The dry bulb temperature is 26 ° C. and the dew point temperature is 17.5
° C.

On the other hand, since the indoor temperature is set at the dry-bulb temperature, assuming that the comfortable humidity at the dry-bulb temperature of 26 ° C. is 60%, the heat exchange temperature ET of the indoor heat exchanger (31) is 17.5.
It must be below ℃. That is, the heat exchange temperature ET is set to 17.
Unless the temperature is 5 ° C. or less, dehumidification against intrusion load cannot be performed and indoor humidity cannot be maintained at 60%.

From the above, the set temperature Trs of the room temperature is set.
When et and target humidity RH-T are set, the heat exchange temperature that should be
ET can be envisioned. That is, when it is assumed that the sensible heat load and the latent heat load are within the predetermined range, the target heat exchange temperature ET-T should be experimentally set to be 3 ° C to 4 ° C lower than the dew point temperature. Become.

Therefore, for example, when the set temperature Trset of the room temperature is 26 ° C., the target temperature which is the target heat exchange temperature.
ET-T is set to 13 ℃ and the set temperature Trset of the room temperature is 25 ℃
In this case, the target temperature ET-T of the heat exchange temperature is set to 12 ° C., and this target temperature ET-T is stored in the memory in advance.

-Control Operation- Next, the control operation of the compressor (21) and the like during the cooling operation will be described. 13 and 14 show the first embodiment.
13 corresponds to FIGS. 6 and 7, and FIG. 13 shows a detailed control operation, and FIG. 14 shows a conceptual operation.

The operation of the basic concept of this control will now be described with reference to FIG. 14. The cooling operation control of this embodiment is almost the same as the operation of FIG. 7 in the first embodiment. In step ST41, it is determined whether or not the indoor temperature Tri is stable. That is, the room temperature control means (51) executes the normal cooling operation until the room temperature Tri reaches the set temperature Trset. After that, when the room temperature Tri stabilizes,
Move to Step ST42, heat exchange temperature of the indoor heat exchanger (31)
It is determined whether ET is within a predetermined range with respect to the target temperature ET-T. And when the heat exchange temperature ET is out of the predetermined range,
In step ST43, the humidity control means (52) calculates the frequency of the compressor (21) and the rotation speed of the indoor fan (3F), and then moves to step ST44 to output the frequency signal and the rotation speed signal. Will be dehumidified.

Next, the detailed control operation will be described with reference to FIG. First, when the cooling operation is started, it is controlled similarly to step ST1 to step ST4 of FIG. 6 in the first embodiment, and when the indoor temperature Tri becomes stable and the indoor temperature Tri becomes lower than the set temperature Trset, the determination of step ST3 is made. If YES, exit the room temperature control loop and move to step ST31.
Enter the humidity control loop.

Then, in step ST31, the humidity control means (52) executes the humidity control, and the heat exchange sensor (Th
-The heat exchange temperature ET detected by e) will be imported. Then, the process proceeds to step ST32, and it is determined whether or not the current heat exchange temperature ET is within a predetermined range with respect to the target temperature ET-T stored in the memory in advance. Specifically, heat exchange temperature ET
Difference between the target temperature and target temperature ET-T ΔET (ΔET = ET-ET-T) is ±
It is determined whether it is within the range of 1 ° C (-1 <ΔET <+1).

When the temperature difference ΔET is within the range of ± 1 ° C., the determination at step ST32 is YES, the process proceeds to step ST33, the current operating state is maintained, and step ST
It will return to 4.

On the other hand, when the temperature difference ΔET is out of the range of ± 1 ° C., the determination in step ST32 becomes NO and the process moves to step ST34, where the current frequency of the compressor (21) and the indoor fan (3F) are present. Will be corrected. That is, as in the first embodiment, the current state point SP-4 in FIG.
If the indoor humidity is RH, the indoor humidity RH is higher than the target humidity RH-T, and the occupants are in a state of feeling "humid heat".

Therefore, the humidity control means (52) increases the frequency of the compressor (21) and at the same time lowers the rotation speed of the indoor fan (3F), and shifts to the state point SP-5 in FIG. , The sensible heat capacity is increased and the latent heat capacity is increased to increase the dehumidification capacity. This point is the characteristic point of the present invention as in the case of the first embodiment, and in normal cooling operation, the compressor (21)
Although the frequency of the indoor fan (3F) and the air volume of the indoor fan (3F) were both reduced proportionally, the rotation speed of the indoor fan (3F) was reduced and the frequency of the compressor (21) was increased to reduce the low pressure. The amount of water to be condensed and condensed is increased.

Then, as the correction of the compressor (21), as in the first embodiment, for example, the present frequency output Comp.o.
A new frequency output Comp.out (Com
Performs proportional control (P control) with p.out = Comp.out + Ch). In addition, as the correction of the indoor fan (3F), proportional control (P control) is performed as in the compressor (21), and the compressor (2
1) Multiply the frequency output Comp.out by a constant (-11) and add the constant (1100) to obtain a new rotation speed Fan.out (rpm)
(Fan.out (rpm) = − 11 × Comp.out + 1100).

After that, the above-mentioned steps from ST34 to
Returning to ST4, the above operation is repeated, and steps ST31 to ST34 constitute a humidity control loop.

As described above, according to this embodiment, when the temperature difference between the room temperature Tri and the set temperature Trset reaches a predetermined value, the latent heat capacity is increased so that the detected heat exchange temperature ET becomes the target temperature ET-T. As a result, dehumidification in the room can be reliably performed, and "humid heat" can be eliminated. Further, it is possible to prevent a decrease in the room temperature, and it is possible to avoid a "too cold" state. As a result, good air conditioning can be performed on the body, and comfort can be improved.

The evaporation temperature detected by the heat exchange sensor (Th-e)
Since ET is used, it is not necessary to provide a humidity sensor (Hu-r), and it is possible to prevent an increase in the number of parts. That is,
Since the detected evaporation temperature ET of the heat exchange sensor (Th-e) can also be used for controlling other actuators, the detection means can be shared and the structure can be simplified.

<Other Embodiments> In each of the above embodiments, the compressor (21) and the indoor fan (3F) are proportionally controlled (P).
However, in the present invention, the compressor (21) and the indoor fan (3F) may be subjected to proportional-plus-integral control (PI control) or fuzzy control. In short, the control may be performed so as to increase the latent heat capacity so that the indoor humidity RH becomes the target humidity RH-T and the heat exchange temperature ET becomes the target temperature ET-T.

In each of the above embodiments, the case of dehumidifying the inside of the room has been described, but the dehumidifying ability may be reduced as an embodiment of the invention of claims 5 and 6.
That is, when the indoor humidity becomes too low in the airtight house, the humidity control means (52) lowers the frequency of the compressor (21) and at the same time increases the rotation speed of the indoor fan (3F). Along with the state line C4 from the state point SP-4 in, the latent heat ability is reduced and the dehumidification ability is reduced while keeping the sensible heat ability. In this respect, as indicated by the chain line arrow in the humidity control in Table 1 above, in normal cooling operation,
The frequency of the compressor (21) and the air volume of the indoor fan (3F) were both reduced proportionally, but instead of the indoor fan (3F)
To increase the heat exchange capacity of the indoor heat exchanger (31), and then to reduce the frequency of the compressor (21) and increase the low pressure to reduce the amount of condensed water. . With respect to this dehumidifying ability reduction control, the latent heat ability is also reduced while performing the cooling operation.

As a result, it is possible to prevent the room temperature from decreasing and avoid the "overdry" condition. Furthermore, the input reduction due to the capacity reduction of the compressor (21) is greater than the input increase due to the increase in the air volume of the indoor fan (3F), so it is possible to reduce the power consumption and to reduce the power cost. You can

In each of the above embodiments, the dehumidifying capacity is increased or decreased while the cooling operation is performed. However, the dry operation may be performed by a separate control. It goes without saying that the control may be executed as one.

Further, the control system of each of the above-described embodiments includes the frequency of the compressor (21) and the indoor fan (3F) shown in FIGS. 4 and 8.
It is of course possible to store a characteristic diagram of sensible heat and latent heat showing the relationship with the number of revolutions in the memory as a map and control the compressor (21) and the indoor fan (3F) based on this map. Is.

In each of the above embodiments, the outdoor unit (2
0) and the indoor unit (30) are provided for each of the air conditioners (10), the present invention may be a multi-type having a plurality of indoor units (30), Further, it goes without saying that it may include a plurality of outdoor units (20).

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of the present invention.

FIG. 2 is a refrigerant circuit diagram of the air conditioner.

FIG. 3 is a control block diagram showing an electric control system.

FIG. 4 is a characteristic diagram of sensible heat and latent heat with respect to a compressor frequency and a fan air volume.

FIG. 5 is a characteristic diagram of compressor capacity with respect to fan air volume.

FIG. 6 is a flowchart of air conditioning control according to the first embodiment.

7 is a flowchart showing a schematic operation of air conditioning control in FIG.

FIG. 8 is a characteristic diagram of sensible heat and latent heat with respect to a compressor frequency and a fan air flow, which shows the room temperature control and the dehumidification control of FIG.

9 is a psychrometric chart showing room temperature control and dehumidification control of FIG.

FIG. 10 is a front view showing an indoor heat exchanger of Example 2.

11 is a side view of the indoor heat exchanger of FIG.

FIG. 12 is a psychrometric chart for explaining the control of the second embodiment.

FIG. 13 is a flowchart of air conditioning control according to the second embodiment.

14 is a flowchart showing a schematic operation of the air conditioning control of FIG.

[Explanation of symbols]

 10 Air conditioner 11 Refrigerant circuit 20 Outdoor unit 21 Compressor 22 Four-way switching valve 23 Outdoor heat exchanger 24 Electric expansion valve 30 Indoor unit 31 Indoor heat exchanger 3F Indoor fan 40 Electric control system 50 CPU 51 Room temperature control means 52 Humidity Control means Th-r Room temperature sensor Hu-r Humidity sensor Th-e Heat exchange sensor

Claims (7)

[Claims] 1. A usage-side heat exchanger comprising a variable capacity compressor (21), a heat source side heat exchanger (23), an expansion mechanism (24), and a variable air volume usage side fan (3F). 31) are connected in sequence and at least the refrigerant circuit (11) capable of cooling operation, the room temperature detecting means (Th-r) for detecting the room temperature, and the temperature detected by the room temperature detecting means (Th-r) are set. A room temperature control means (51) for controlling the capacity of the compressor (21) and the air volume of the use side fan (3F) so that the temperature becomes the temperature; a humidity detection means (Hu-r) for detecting indoor humidity; When the temperature difference between the room temperature detected by the room temperature detection means (Th-r) and the set temperature reaches a predetermined value, the room temperature control means (51)
Instead of the above, the humidity control means (5) for changing the latent heat capacity so that the detected humidity of the humidity detection means (Hu-r) becomes the target humidity.
2) An operation control device for an air conditioner, characterized by comprising: 2. A usage-side heat exchanger including a variable capacity compressor (21), a heat source side heat exchanger (23), an expansion mechanism (24), and a variable air volume usage side fan (3F). 31) are connected in sequence and at least the cooling circuit (11) capable of cooling operation, the room temperature detecting means (Th-r) for detecting the room temperature, and the detected temperature of the room temperature detecting means (Th-r) are set temperatures. Room temperature control means (51) for controlling the capacity of the compressor (21) and the air flow rate of the use side fan (3F) so that the evaporation temperature of the refrigerant in the use side heat exchanger (31) is detected. When the temperature difference between the room temperature detected by the temperature detection means (Th-e) and the room temperature detection means (Th-r) with respect to the set temperature reaches a predetermined value, the room temperature control means (51)
In place of the above, the operation control of the air conditioner is provided with a humidity control means (52) for changing the latent heat capacity so that the temperature detected by the evaporation temperature detection means (Th-e) becomes a target temperature. apparatus. 3. The operation control device for an air conditioner according to claim 1 or 2, wherein the humidity control means (52) is configured to maintain a predetermined sensible heat capacity and increase the latent heat capacity. An air conditioner operation control device characterized by: 4. The operation control device for an air conditioner according to claim 3, wherein the humidity control means (52) increases the capacity of the compressor (21) and at the same time reduces the air volume of the use side fan (3F). An air conditioner operation control device characterized by being configured to increase the latent heat capacity. 5. The operation control device for an air conditioner according to claim 1 or 2, wherein the humidity control means (52) is configured to hold a predetermined sensible heat capacity and reduce the latent heat capacity. An air conditioner operation control device characterized by: 6. The operation control device for an air conditioner according to claim 5, wherein the humidity control means (52) reduces the capacity of the compressor (21) and at the same time increases the air volume of the use side fan (3F). An air conditioner operation control device characterized by being configured to reduce the latent heat capacity. 7. The operation control device for an air conditioner according to claim 2, wherein the evaporation temperature detecting means (Th-e) detects the intermediate refrigerant temperature in the heat exchanger on the use side (31). An operation control device for an air conditioner, which is provided in the heat exchanger (31).