JP3096527B2 - Operation control method for air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operation control method for an air conditioner having an indoor unit.

[0002]

2. Description of the Related Art As an air conditioner of this type, for example, an outdoor unit having a compressor and an outdoor heat exchanger and a plurality of units having an indoor heat exchanger disclosed in Japanese Patent Application Laid-Open No. 3-50466 are known. 2. Description of the Related Art A cooling / heating device having a configuration in which an indoor unit and an indoor unit are connected by a piping between units is well known.

[0003] In the above-mentioned conventional apparatus, the flow control of the refrigerant to each of a plurality of indoor units is controlled by a temperature sensor installed in the indoor heat exchanger so that the indoor heat exchanger temperature of each indoor unit becomes equal, for example, during heating. To explain by way of example, the electric valve of the indoor unit having a high heat exchanger temperature is controlled by reducing the opening, and the electric valve of the indoor unit having a low temperature is controlled by opening the opening.

[0004]

However, since the setting of the outlet temperature in the above-mentioned conventional apparatus is determined irrespective of the type of the indoor unit and the set wind speed, for example, the floor is installed at a short distance from the hot air outlet to a person. In the type indoor unit, a comfortable heating state can be obtained by "low temperature low wind operation",

[0005] In the case of an indoor unit of a cassette type embedded in the ceiling or a type suspended from the ceiling, warm air stays in the ceiling and hot air does not reach a person, so that comfortable heating operation is not performed. In addition, since a feeling of warm air cannot be obtained even with a strong wind operation at a low temperature, it is necessary to perform a heating operation at a high temperature and a high wind speed in this type of indoor unit.

That is, in an air conditioner having an indoor unit, it is necessary to set the blowing temperature and the set wind speed to an optimum value in accordance with the type of the indoor unit so that the air conditioner can be operated. Had been an issue.

[0007]

According to the present invention, as a specific means for solving the above-mentioned problems of the prior art, a compressor for refrigerant, a four-way valve, an outdoor heat exchanger, an outdoor expansion valve, an indoor electric valve,
In an air conditioner in which a cooling / heating circuit is formed by sequentially connecting an indoor heat exchanger and an accumulator, a target outlet temperature is determined from a difference between a set room temperature and a measured room temperature, a set wind speed, and a type of an indoor unit. An operation control method in the air conditioner, wherein an air conditioning index is calculated from the target outlet temperature and the measured outlet temperature, and the number of rotations of the compressor is controlled based on the air conditioning index;

A plurality of indoor units having an indoor heat exchanger are provided, and a target outlet temperature is determined from a difference between a set room temperature and a measured room temperature, a set wind speed, a type and a capacity of the indoor unit, and the target outlet temperature is measured. The air conditioning index of each indoor unit is calculated from the blown air temperature and summed up, and the operation control method for the air conditioner according to the above description, wherein the rotation speed of the compressor is controlled based on the sum of the air conditioning indexes, An object of the present invention is to solve the above-described problem of the related art.

[0009]

[Action]

Heating operation: Determine the target outlet temperature of warm air from the difference between the set room temperature and the measured room temperature, the set wind speed, the type and capacity of the indoor unit, and calculate the difference between the measured outlet temperature and the target outlet temperature, for example, the capacity of the indoor unit. The air-conditioning index for each indoor unit is calculated by multiplying the air-conditioning indices. If the sum of the air-conditioning indices is negative, the rotation of the compressor is increased because the heating capacity of the entire system is insufficient. If so, the overall heating capacity is excessive, so reduce the rotation of the compressor.

[0010] Cooling operation: The target blow-off temperature of the cool air is determined from the difference between the set room temperature and the measured room temperature, the set wind speed, the type and capacity of the indoor unit, and the difference between the measured blow-out temperature and the target blow-out temperature is determined. The air-conditioning index of each indoor unit is calculated by multiplying the capacity of each of the indoor units. If the sum of the air-conditioning indices is positive, the cooling capacity of the entire system is insufficient. If the sum is negative, the overall heating capacity is excessive, so the rotation of the compressor is reduced.

[0011]

FIG. 3 shows an outdoor unit U0 and an indoor unit U.
1 shows an example of an air conditioner system in which U2 is connected in parallel. In the figure, reference numeral 1 denotes a compressor driven by a gasoline engine, a gas engine, an electric motor, or the like;
A four-way valve for heating switching, 3 is an indoor heat exchanger, 4 is an indoor electric valve (hereinafter, referred to as an electric valve), which acts as an expander during cooling and acts as a refrigerant distribution control valve of each indoor unit during heating. Is a receiver tank, 6 is an outdoor expansion valve, 7 is an outdoor heat exchanger, 8 is an accumulator, each of which is a conventionally well-known device, which is sequentially connected via a refrigerant pipe L and is shown by a solid line. A cooling circuit A and a heating circuit B indicated by a broken line are formed.

The indoor units U1 and U2 exchange the air existing in the room with a refrigerant such as Freon flowing through the indoor heat exchanger 3 and blow it into the room, in addition to the indoor heat exchanger 3 and the motor-operated valve 4, respectively. An indoor fan 12, a temperature sensor 9 for measuring the temperature of air when exchanging heat with the indoor heat exchanger 3 and blowing out the room, and a temperature sensor 10 for measuring the temperature of air taken in from the room (that is, room temperature). And each is connected to transmit measurement data to the controller 11 of the outdoor unit U0 and to operate based on a control signal output from the controller.

The indoor units U1 and U2 include:
A remote controller 13 is electrically connected to each of the switches. The remote controller 13 has a switch for starting / stopping the system, a switch for setting a room temperature, a switch for setting a wind speed, etc. (none of them are shown). Is provided.

The refrigerant compressed by the compressor 1 and discharged to the refrigerant pipe L can be circulated in the two directions of the solid line and the broken line by switching the four-way valve 2 as described above.

When the heating circuit B shown by the dashed line is formed, the refrigerant which has been compressed by the compressor 1 and has been in a high temperature and high pressure state flows into the indoor units U1 and U2 via the four-way valve 2. In the indoor heat exchanger 3, the indoor fan 1
2 exchanges heat with the room air to be blown and heats it, and the refrigerant itself cools down and condenses. The indoor unit U
The distribution control of the refrigerant to each of 1 and U2 is performed by adjusting the opening of the electric valve 4 using a step motor or the like so as to correspond to each load.

The liquefied refrigerant is adiabatically expanded by the outdoor expansion valve 6 to become a low-temperature and low-pressure gaseous substance and passes through the outdoor heat exchanger 7 to be blown by an outdoor fan (not shown). The air is warmed by the outside air having a high temperature and flows back to the compressor 1 via the four-way valve 2 and the accumulator 8.

On the other hand, when the four-way valve 2 is switched to form the cooling circuit A shown by the solid line, the refrigerant which has been compressed by the compressor 1 and has become high temperature and high pressure when passing through the outdoor heat exchanger 7 Cooled and condensed by the relatively low-temperature outside air blown by an outdoor fan (not shown), the receiver tank 5
Through each of the indoor units U1 and U2, in this case, adiabatic expansion by passing through the electric valve 4 functioning as an expansion valve, flows into the corresponding indoor heat exchanger 3 as a low-temperature / low-pressure gas body, The indoor fan 12 exchanges heat with the room air blown from the room to cool the room air and returns to the compressor 1 via the four-way valve 2 and the accumulator 8.

First, a heating operation will be described as an example.
From the indoor units U1, U2, the remote controller 13 to the controller of the controller 11, the types of indoor units such as the blowout temperature, the indoor temperature, the cassette type embedded in the ceiling surface, the ceiling hanging type suspended from the ceiling, and the floor type provided on the floor, and the like. Information on capacity, set room temperature, set wind speed, and presence / absence of operation is input.
For example, the rotation of the compressor 1 is controlled by the calculation based on FIG.

When calculating the target blowout temperature Trgt-i (i is the number of the indoor unit) of each indoor unit Ui, its characteristics are taken into consideration depending on the type of the indoor unit Ui and the wind speed to be set.

For example, in the case of a cassette type to be embedded in the ceiling, it is necessary to increase the blowing speed of the hot air in order to prevent hot air from accumulating on the ceiling. The blowing temperature is required. On the other hand, when the wind speed is set to "weak wind", the blow-out temperature is set to a slightly lower temperature in order to prevent accumulation of hot air on the ceiling.

On the other hand, in the floor installation type in which warm air is blown from the floor, a high outlet temperature is not required because the distance between the outlet and the person is short, so a lower temperature is set.

In consideration of various conditions as described above, even if the difference between the set room temperature and the measured room temperature is the same as shown in FIG. 2, for example, depending on the type of the indoor unit Ui and the air blowing conditions, etc.
Different target outlet temperatures Trgt-i are set.

One specific control example during the heating operation will be described with reference to the flowchart of FIG. 1 in which there are n (n ≧ 2) indoor units. In step S1, i = 1, that is, the first indoor unit. Select unit U1 and step S2
Then, the set room temperature Tset-1, the measured room temperature Troom-1, the blowout temperature Tout-1, the set wind speed FM-1, the indoor unit type TP-1, and the indoor unit capacity Cap-1 in the indoor unit U1 are input.

In step S3, the target outlet temperature Trgt-1 in the indoor unit U1 is determined based on the relational expression of FIG.
, And in a subsequent step 4, the air blowing temperature Tout-1 measured by the temperature sensor 9 and the target blowing temperature calculated by the above calculation.
An outlet temperature difference δout-1 from Trgt-1 (= Tout-1-Trgt-1) is calculated and calculated.

In step S5, the air-conditioning index during the heating operation, that is, the heating index H1, is calculated by using the calculated outlet temperature difference δ.
It is obtained as the product of out-1 and the indoor unit capacity Cap-1.

If the heating index H1 is positive, the room in which the indoor unit is placed is overheated, and if negative, it means that the room is insufficiently heated. Since the capacity is converted into an index by taking into account the capacity Cap-1 of the indoor unit U1, the excess or deficiency of the capacity during the heating operation can be accurately grasped.

In step S6, a determination is made on i. In this case, since i = 1, the process proceeds to the side of i <n.
In step S7, the new i is set to i (= 1) + 1 = 2, and the process returns to step S2. Then, Step S2 to Step S
The above control 6 is repeated until i = n. That is, the heating index Hi is calculated by calculation for all the indoor units U1, U2,... Un.

Then, in step S8, all the heating indexes Hi (i; 1 to n) are summed, and the sum is obtained.

In step S9, the sum of the heating indices Hi obtained by the above calculation is determined. If this value is negative, the heating is insufficient in the entire system, so that the flow shifts to step S10 and the rotational speed of the compressor 1 is reduced. Raise the heating capacity. On the other hand, if the value is positive, the heating of the entire system is too high, so the process proceeds to step S11, where the rotation speed of the compressor 1 is reduced, and the heating capacity is reduced. Also, if the sum is zero, there is no excess or deficiency in the heating capacity of the entire system,
The rotation speed of the compressor 1 is not changed.

FIG. 4 shows an example of control during the cooling operation. The basic control is the same as in the case of the heating operation shown in FIG.

Even in the cooling operation, when calculating the target outlet temperature Trgt-i (i is the number of the indoor unit) of each indoor unit Ui in step P3, the indoor unit U
The characteristics are added depending on the type of i and the set wind speed.

That is, during the cooling operation, the greater the wind speed, the more the sense of cold wind is felt. Therefore, in a floor-mounted type in which the distance between the cold air outlet and the person is short, the temperature and the weakness are higher than those of the ceiling-mounted indoor unit. Set the wind speed.

Then, in step P4, an outlet temperature difference δout-i (= Tout-i-Trgt-i) between the outlet temperature Tout-i measured by the temperature sensor 9 and the target outlet temperature Trgt-i is obtained, and in step P5 The air conditioning index during the cooling operation, that is, Ci, is obtained as the product of the blowout temperature difference δout-i and the indoor unit capacity Cap-i.

In the case of the cooling index Ci, if the value is positive, the room in which the indoor unit is placed has insufficient cooling, and if the value is negative, the room has too much cooling.

For this reason, if it is determined in step P9 that the sum of the cooling indexes Ci is positive, the process proceeds to step P10 in order to increase the cooling capacity of the entire system, the rotational speed of the compressor 1 is increased, and it is determined as negative. Then, the process proceeds to step P11 to reduce the cooling capacity, and the rotation speed of the compressor 1 is reduced. If the sum is zero, there is no excess or deficiency in the cooling capacity, so that the rotation speed of the compressor 1 is not changed.

Since the present invention is not limited to the above embodiment, various modifications can be made without departing from the spirit of the appended claims.

For example, in the above embodiment, the target outlet temperature Trgt-i is changed depending on the type and the set wind speed of the indoor unit Ui in both the heating operation and the cooling operation. Is not affected by
The target outlet temperature at the time of cooling can be uniquely set simply by the difference between the set room temperature and the actually measured room temperature.

The control of each indoor unit Ui is performed individually by adjusting the opening of the motor-operated valve 4 according to the magnitude of the air conditioning index (Hi, Ci).

Even when the number of the indoor units Ui is 1, that is, when only one indoor unit is used, the operation is naturally controlled in the same manner.

[0040]

As described above, according to the present invention, a refrigerant compressor is connected to a four-way valve, an outdoor heat exchanger, an outdoor expansion valve, an indoor electric valve, an indoor heat exchanger, an accumulator, and the like in this order. In an air conditioner in which a heating circuit is formed, a target outlet temperature is determined from a difference between a set room temperature and a measured room temperature, a set wind speed, and a type of an indoor unit, and an air conditioning index is calculated from the target outlet temperature and the measured outlet temperature. An operation control method for an air conditioner, comprising controlling a rotation speed of a compressor based on the air conditioning index,

A plurality of indoor units having an indoor heat exchanger are provided, and a target outlet temperature is determined from a difference between a set room temperature and a measured room temperature, a set wind speed, a type and a capacity of the indoor unit, and the target outlet temperature is measured. Since the air conditioning index of each indoor unit is calculated and summed from the blown air temperatures, and the air conditioning index is controlled based on the sum of the air conditioning indexes, the operation control method for the air conditioner according to the above description,

Even if the types and capacities of the indoor units to be installed vary from room to room, all the indoor units are operated under the optimum conditions, and the sum of the air-conditioning indices for all the indoor units is obtained to determine the rotational speed of the compressor. , The air conditioning is good and the energy efficiency is excellent.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a control method during a heating operation.

FIG. 2 is an explanatory diagram showing a procedure for setting a target outlet temperature Trgt during a heating operation.

FIG. 3 is an apparatus configuration diagram of an embodiment.

FIG. 4 is an explanatory diagram showing a control method during a cooling operation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 2 Four-way valve 3 Indoor heat exchanger 4 Electric valve 5 Receiver tank 6 Outdoor expansion valve 7 Outdoor heat exchanger 8 Accumulator 9, 10 Temperature sensor 11 Controller 12 Indoor fan U0 Outdoor unit U1, U2 Indoor unit A Cooling circuit B Heating circuit L Refrigerant pipe

Claims (2)

(57) [Claims] An air conditioner in which a cooling / heating circuit is formed by sequentially connecting a refrigerant compressor with a four-way valve, an outdoor heat exchanger, an outdoor expansion valve, an indoor electric valve, an indoor heat exchanger, an accumulator, and the like. In, the target outlet temperature is determined from the difference between the set room temperature and the measured room temperature, the set wind speed, and the type of indoor unit, an air conditioning index is calculated from the target outlet temperature and the measured outlet temperature, and the compressor is determined based on the air conditioning index. An operation control method for an air conditioner, comprising controlling the number of revolutions of the air conditioner. 2. A target outlet temperature is determined based on a difference between a set room temperature and a measured room temperature, a set wind speed, a type and a capacity of the indoor unit, and a plurality of indoor units each having an indoor heat exchanger. The operation control method for an air conditioner according to claim 1, wherein the air conditioning index of each indoor unit is calculated and summed from the measured outlet temperatures and the total number of the air conditioning indexes is controlled based on the sum of the air conditioning indexes.