JP3223918B2 - Multi-room air conditioning system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-room air conditioning system in which a plurality of indoor units are connected to one outdoor unit, and the flow rate of refrigerant is controlled by an electric expansion valve.

[0002]

2. Description of the Related Art In recent years, a demand for a multi-room air conditioning system in which a plurality of indoor units are connected to one outdoor unit has been increasing in terms of outdoor space saving, exterior characteristics, and small power supply capacity. .

Conventionally, in this multi-chamber air conditioning system, a refrigerant flow control device for controlling a refrigerant flow to each indoor unit is provided in a liquid side refrigerant pipe of a refrigeration cycle using a variable capacity (frequency) compressor. There has been proposed an apparatus that controls the compressor capacity by comparing the capacity of an outdoor unit and the capacity of each indoor unit, and controls the flow rate of refrigerant to each indoor unit. (For example,
The conventional multi-room air conditioning system will be described below with reference to the drawings.

FIG. 1 is a refrigeration cycle diagram of a conventional multi-room air conditioning system.

[0005] This multi-room air conditioning system is constructed by connecting one outdoor unit 1, one branch unit 2 and a plurality of indoor units, in this example, three indoor units 3a, 3b and 3c. Is done.
In the outdoor unit 1, an inverter-driven frequency variable compressor 4 is provided.
(Hereinafter simply referred to as a compressor), an outdoor heat exchanger 5, a four-way valve 6 for cooling / heating switching, and an electric expansion valve 7, and the indoor heat exchangers 8a, 8c in the indoor units 3a, 3b, 3c, respectively.
b, 8c are provided. The outdoor unit 1 is connected to the branch 2, and the liquid-side main pipe 9 is branched into liquid-side branch pipes 10a, 10b, and 10c inside the branch unit. Each of the liquid-side branch pipes in the branching machine has an electric expansion valve 11a, 1
1b and 11c are provided. Branch machine 2 and indoor unit 3
a, 3b, 3c are the liquid side branch pipes 10a, 10b, 10c.
c and the gas side branch pipes 12a, 12b, 12c. The branch unit 2 and the outdoor unit 1 are connected by a gas-side main pipe 13.

The liquid side main pipe inside the outdoor unit 1 and the compressor 4
A bypass circuit 15 for connecting the suction pipe 14 to the
An auxiliary aperture 16 is provided in the bypass circuit 15. Each of the indoor units 3a, 3b, and 3c has an indoor temperature sensor 17 for detecting the room temperature of the room in which the indoor unit is installed.
a, 17b, 17c and operation setting circuits 30a, 30b, 30c capable of setting an operation mode (cooling or heating) desired by the occupant, room temperature, operation, and stop are provided.
The outdoor unit 1 is provided with a saturation temperature sensor 18 for detecting a low pressure saturation temperature of the refrigeration cycle and a suction temperature sensor 19 for detecting a suction temperature of the compressor 4.

In this refrigeration cycle, during cooling, the refrigerant discharged from the compressor 4 flows from the four-way valve 6 to the outdoor heat exchanger 5 where it exchanges heat with outdoor air to condense and liquefy.
The pressure is reduced by the electric expansion valve 7 to an intermediate pressure. Then, a part of the liquid refrigerant is diverted to the bypass circuit 15, and the rest flows through the liquid-side main pipe 9, and flows into the liquid-side branch pipes 10 a, 10 b, and 1 inside the branching machine.
Branch to 0c. The valve opening of the electric expansion valve 7 is
Are controlled so that they are most efficient and liquid compression is not performed (not described), and the valve openings of the electric expansion valves 11a, 11b, and 11c are controlled so as to correspond to the load of each room. (Not described), the refrigerant also has a low pressure at a flow rate corresponding to each load, and the indoor heat exchangers 8a, 8b, 8
c, and after evaporating, the gas-side branch pipes 12a, 12b, 12c inside the branching machine 2 pass through the gas-side main pipe 13, the four-way valve 6
And is sucked into the compressor 4 again. The liquid refrigerant from the bypass circuit 15 is decompressed by the auxiliary throttle 16 and flows to the suction pipe 14. Further, the compressor frequency is determined by a control method described later according to the total load.

At the time of heating, the refrigerant discharged from the compressor 4
The four-way valve 6 is switched to branch from the gas-side main pipe 13 to the gas-side branch pipes 12a, 12b, and 12c inside the branching machine 2, flow to the indoor heat exchangers 8a, 8b, and 8c, condense and liquefy, and branch to the liquid side. Motorized expansion valve 11a on pipes 10a, 10b, 10c,
The pressure is reduced to an intermediate pressure at 11b and 11c. The valve opening of the electric expansion valves 11a, 11b, 11c is controlled to an opening corresponding to the load of each room as in the case of cooling (not described), so that the refrigerant exchanges indoor heat at a flow rate corresponding thereto. Flow through the vessels 8a, 8b, 8c. The refrigerant having the intermediate pressure diverts a part of the liquid refrigerant to the bypass circuit 15, and the remainder is reduced in pressure by the electric expansion valve 7 to a low pressure, flows through the outdoor heat exchanger 5, evaporates, and then evaporates. And is sucked into the compressor 4 again. The liquid refrigerant from the bypass circuit 15 is decompressed by the auxiliary throttle 16 and decompressed, and flows to the suction pipe 14.
Further, the compressor frequency is determined by a control method described later according to the total load as in the case of cooling.

Next, a method of controlling the compressor frequency will be described. FIG. 2 is a block diagram of control of the compressor frequency, and FIG.
FIG. 3 is a temperature zone division diagram of a difference temperature ΔT between the room temperature Tr and the set temperature Ts.

First, in the indoor unit 3a, the output of the indoor temperature sensor 17a is sent from the indoor temperature detecting circuit 31 to the differential temperature calculating circuit 32 as a temperature signal, and is set by the operation setting circuit 30a in the indoor temperature setting storage circuit 33. The determined set temperature and operation mode are discriminated and sent to the temperature difference calculating circuit 32, where the temperature difference ΔT (= Tr−Ts) is calculated, converted into the load number Ln value shown in FIG. The difference temperature signal is used. For example, at the time of cooling operation, Tr = 27.3 ° C., Ts =
Assuming that the temperature is 26 ° C., Ln = 6 at the temperature difference ΔT = 1.3 ° C. Further, the ON-OFF determination circuit 34 determines whether the indoor unit 3a is operated (ON) or stopped (OFF) set by the operation setting circuit 30a, and further stores the rated capacity of the indoor unit 3a in the rated capacity storage circuit 35. The rated capacity signal, the differential temperature signal, the operation mode signal, and the ON / OFF discrimination signal are transmitted from the signal transmitting circuit 38 to the signal receiving circuit 4 of the branching machine 2.
Send to 1. A similar signal is sent from the indoor units 3b and 3c to the signal receiving circuit 41. The signal received by the signal receiving circuit 41 reads out a load constant from the load constant table shown in Table 1 below and transmits the read load constant to the load constant calculation circuit 42. The load constant calculation circuit calculates the total load and calculates the sum of the load constants. The signal is sent from the signal sending circuit 43 to the signal receiving circuit 50 of the outdoor unit 1.

A compressor frequency calculation circuit 51 determines the frequency of the compressor 4 by multiplying the sum of the load constants of the branching machine 2 by a constant.

[0012]

[Table 1]

As an example, a case where signals from the indoor units 3a, 3b and 3c are shown in Table 2 below will be described.

[0014]

[Table 2]

According to Tables 1 and 2, the indoor units 3a, 3b, 3c
Are 1.5, 1.0, and 1.9, respectively.
Assuming that A is a constant, the frequency Hz of the compressor is as follows: Hz = A × (1.5 + 1.0 + 1.9) = A × 4.4, and the calculation result is sent to the compressor drive circuit as a frequency signal to be transmitted to the compressor. 4 is performed. Thereafter, a calculation is performed based on the rated capacity signal, the differential temperature signal, the operation mode signal, and the ON / OFF determination signal of each of the indoor units 3a, 3b, and 3c at predetermined intervals, and the calculation result is transmitted to the compressor drive circuit as a frequency signal. Then, the frequency of the compressor 4 is controlled.

As described above, by controlling the compressor frequency in accordance with the sum of the required capacity of each room, the most efficient and reliable on the refrigeration cycle can be obtained. , Necessary abilities can be allocated to necessary rooms, thereby improving comfort and saving energy.

[0017]

However, the above-mentioned conventional multi-room air conditioning system has the following problems.

That is, for example, in the cooling operation, the indoor unit 3
a, 3b, and 3c, when the differential temperature signals are both Ln = 6 and the rated capacities of the indoor units 3a, 3b, and 3c are the same as those in Table 2, the frequency Hz of the compressor 4
Is Hz = A × (2.0 + 2.5) = A × 4.5. The temperature difference signals of the indoor units 3a, 3b, 3c are all Ln =
6, Hz = A × (2.0 + 2.5 + 3.
2) = A × 7.7, and assuming that this is the allowable operating value of the compressor 4, it becomes 4.5 / 7.7 = 0.58, which is about 4
This means that there is some room left. That is, the indoor unit 3
a, 3b, and 3c are in the maximum load state, and require the outdoor unit 4 to have the maximum capacity of the indoor unit. On the other hand, the outdoor unit 4 leaves the indoor unit 3a with a capacity of about 40%. , 3b, 3c
Is supplying the refrigerant. Therefore, even when the capacity of the indoor unit is at the maximum load, only the rated capacity corresponding to the load constant can be obtained even though the outdoor unit 4 has a capacity margin, and much time is required to reach the set temperature. I needed it.

The same problem occurs even when the indoor unit 3a starts operating under the maximum load state while the indoor units 3a, 3b, 3c operate at a low load.

In view of the above-mentioned problems, the multi-room air conditioning system of the present invention does not complicate the configuration of the refrigeration cycle and has a sufficient capacity of the outdoor unit 4 with the indoor unit having the maximum load. The purpose of this is to supply the capacity margin to the indoor unit having the maximum load.

In addition, the multi-room air conditioning system of the present invention supplies an indoor unit with a small load to a room unit having a maximum load without supplying a capacity higher than a required capacity. To improve comfort and save energy
The purpose is to plan.

[0022]

In order to solve the above-mentioned problems, a multi-room air conditioning system according to the present invention comprises an indoor temperature setting means capable of setting a desired indoor temperature in each of the indoor units and detecting the indoor temperature. Provided a room temperature detecting means, and a room temperature calculating means for calculating a temperature difference between the set room temperature and the room temperature from the room temperature setting means and the room temperature detecting means,
Further, capacity determining means for determining the rated capacity of each of the indoor units and on / off determining means for determining whether each of the indoor units is in operation or stopped is provided. Divided into zones, further provided with a rated air flow variable means and a rated air flow set value for each of the indoor units within the temperature zone range, and a load constant corresponding to an indoor load for each temperature zone and for each of the rated capacities of the indoor units. In addition to the above, a maximum air conditioning load zone of a predetermined temperature zone or less is provided for cooling in a predetermined temperature zone or more, and a load constant storage unit for determining and storing a load constant of a rated capacity or more for each rated capacity of an indoor unit is provided, The compressor capacity is calculated at predetermined intervals using data obtained from the temperature difference calculating means, the capacity determining means, the on / off determining means, and the load constant storing means. When there is a differential temperature signal corresponding to the air conditioning load maximum zone even in one room, when the compressor capacity is less than the allowable operation value, the load constant of the air conditioning load maximum zone obtained from the load constant storage means is used. Compressor capacity control means for controlling the capacity of the variable capacity (frequency) compressor based on the calculated capacity and the capacity value;
When the compressor capacity meets the operation allowance, a compressor capacity control means is provided within the range of the operation allowance, and the rated air flow is set such that the set air flow is larger than the set value obtained from the rated air flow set value. By performing the air volume variable control of each indoor unit using the air conditioning load maximum zone air volume set value that is not set in the variable range, for indoor units with a small load,
Since the compressor frequency is controlled to supply the capacity according to the load and to supply the extra outdoor capacity only to the indoor unit with the maximum load, the time to reach the set temperature can be shortened, and the comfort can be increased. Performance and energy saving.

Further , even one room corresponds to the maximum zone of the air conditioning load.
If there is a differential temperature signal, the compressor capacity is
Air conditioner is obtained from the load constant storage means.
The capacity calculated using the load constant of the load maximum zone,
Based on this capacity value, the capacity (frequency) variable type compressor
A compressor capacity control means for controlling the capacity of the compressor.
If the quantity meets the operation allowance, it is within the operation allowance
The compressor capacity control means is provided, and the rated air volume is further set.
If the set air volume is larger than the set value obtained from the value
Maximum air-conditioning load zone not set in the rated air flow variable range
The air volume variable control of each indoor unit is performed using the air volume set value.
If you do, set a delay time after the compressor capacity is changed.
It is what you do. Use the air-conditioning load maximum zone airflow setting value
By performing variable air volume control of each indoor unit, the load
For indoor units with a small number, provide the capacity according to the load.
Power supply, and provide sufficient outdoor capacity only for the indoor unit with the maximum load.
To control the compressor frequency to supply
Time to reach can be shortened, improving comfort
By performing a variable air volume control with a delay time after the compressor capacity is varied, it is possible to prevent the path balance from being lost due to the rapid indoor air volume increase and to cause fan condensation due to rapid indoor air volume increase. Preventing or increasing the indoor air volume without raising the high pressure during heating prevents a feeling of cool air, which significantly deteriorates comfort and prevents excessive subcools from forming an appropriate refrigeration cycle. , Quality can be improved.

Further , even one room corresponds to the maximum air conditioning load zone.
If there is a differential temperature signal, the compressor capacity is
Air conditioner is obtained from the load constant storage means.
The capacity calculated using the load constant of the load maximum zone,
Based on this capacity value, the capacity (frequency) variable type compressor
A compressor capacity control means for controlling the capacity of the compressor.
If the quantity meets the operation allowance, it is within the operation allowance
The compressor capacity control means is provided, and the rated air volume is further set.
If the set air volume is larger than the set value obtained from the value
Maximum air-conditioning load zone not set in the rated air flow variable range
The air volume variable control of each indoor unit is performed using the air volume set value.
In addition to performing air volume variable control of each indoor unit,
The maximum load adjustment zone is released and the air volume increases
When the air flow falls below the rated air flow variable range
While maintaining the fixed time, gradually reduce the air volume and
The variable air volume control is performed so that the air volume is set. Sky
The maximum load of the indoor unit using
By performing variable air volume control, indoor units with small loads can be controlled.
Supply the capacity corresponding to the load, and
Compressor circumference to supply extra outdoor capacity to indoor units only
To control the wave number, set the time to reach the set temperature.
Faster, improved comfort and energy saving
While performing the air volume variable control of each indoor unit, when the air conditioning load maximum zone is released and the air volume falls from the air conditioning load maximum zone air volume set value to the rated air volume variable range, while maintaining a certain time, By performing the air volume variable control so as to reduce the air volume stepwise so that the air volume becomes a predetermined set air volume, it is possible to prevent a rapid air volume reduction and eliminate a sense of incongruity that is actually heard, thereby improving comfort.

Further , even one room corresponds to the maximum zone of the air conditioning load.
If there is a differential temperature signal, the compressor capacity is
Air conditioner is obtained from the load constant storage means.
The capacity calculated using the load constant of the load maximum zone,
Based on this capacity value, the capacity (frequency) variable type compressor
A compressor capacity control means for controlling the capacity of the compressor.
If the quantity meets the operation allowance, it is within the operation allowance
The compressor capacity control means is provided, and the rated air volume is further set.
If the set air volume is larger than the set value obtained from the value
Maximum air-conditioning load zone not set in the rated air flow variable range
The air volume variable control of each indoor unit is performed using the air volume set value.
The difference temperature signal corresponding to the air conditioning load maximum zone
Time lapse storage means for storing the time lapse since the detection of
With the data obtained from the time lapse storage means.
Control compressor capacity control and indoor air volume control with time limit
Things. Using the air conditioning load maximum zone airflow setting value
Note that by performing variable air volume control of each indoor unit,
Supply the capacity according to the load to
Supply extra room capacity only to the indoor unit with the maximum load
To reach the set temperature in order to control the compressor frequency
Time to get to work faster, improving comfort and
And time lapse storage means for storing the time lapse since the detection of the temperature difference signal corresponding to the air conditioning load maximum zone, and using the data obtained from the time lapse storage means. By controlling the compressor capacity control and indoor air volume control with a time limit, it is possible to prevent dew condensation around the blow-off and mist blowing phenomenon due to rinsing during cooling, and improve quality and comfort. .

[0026]

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

The refrigeration cycle diagram of the first embodiment of the multi-chamber air conditioning system according to the present invention is the same as that of the conventional example, and therefore the description is omitted. In this embodiment, one branch unit 2 and three indoor units 3a are provided for one outdoor unit 1;
The case where 3b and 3c are connected will be described. FIG. 2 is a block diagram showing the flow of control of the compressor frequency, and FIG. 4 is a temperature zone division diagram of a temperature difference ΔT between the room temperature Tr and the set temperature Ts.

First, in the indoor unit 3a, the output of the indoor temperature sensor 17a is sent from the indoor temperature detecting circuit 19a to the differential temperature calculating circuit 32 as a temperature signal, and is set by the operation setting circuit 30a in the indoor temperature setting storage circuit 33. The determined set temperature and operation mode are determined and sent to the differential temperature calculation circuit 32. Here, the temperature difference ΔT (= Tr−Ts) is calculated,
The value is converted into a load number Ln value shown in FIG. For example, Tr = 29.3 ° C. during cooling operation,
Assuming that Ts = 26 ° C., the air-conditioning load maximum zone Ln = 8 at the temperature difference ΔT = 3.3 ° C. The ON / OFF determination circuit 34 sets the indoor unit 3a set by the operation setting circuit 30a.
Of the indoor unit 3a is stored in the rated capacity storage circuit 35, and these rated capacity signal, differential temperature signal, operation mode signal, ON-OFF The determination signal is sent from the signal sending circuit 38 to the signal receiving circuit 41 of the branching machine 2. A similar signal is sent from the indoor units 3b and 3c to the signal receiving circuit 41. The signal received by the signal receiving circuit 41 reads a load constant from the load constant table shown in Table 3 below, transmits the read load constant to the load constant calculation circuit 42, calculates the total load in the load constant calculation circuit, and sums the load constants. From the signal transmission circuit 43 to the signal reception circuit 50 of the outdoor unit 1.

The compressor frequency calculation circuit 51 determines the frequency of the compressor 4 by multiplying the sum of the load constants of the branching machine 2 by a constant.

[0030]

[Table 3]

As an example, a case where the signals from the indoor units 3a, 3b and 3c at the start of the cooling operation, as shown in Table 4 below, will be described.

[0032]

[Table 4]

From Tables 3 and 4, the indoor units 3a, 3b, 3c
Are 2.4, 3.0, and 0, respectively. Therefore, the frequency Hz of the compressor 4 is given by: Hz = A × (2.4 + 3.0 + 0) = A × 5.4 where A is a constant.

The allowable operation value of the compressor 4 is determined by the indoor units 3a, 3
2.0, 2.5, 3.2 corresponding to the rated capacities of b and 3c
Is 7.7, the frequency calculation result is
4 and has a margin of about 30%, and sends the calculation result as a frequency signal to a compressor drive circuit (not shown) to control the frequency of the compressor 4. Do. Thereafter, the rated capacity signal, the differential temperature signal, the operation mode signal, and the ON
-Calculation is performed from the OFF determination signal, and both indoor units are Ln
= 7, and the calculation result is sent to a compressor drive circuit (not shown) as a frequency signal to control the frequency of the compressor 4.

Next, a case where the operation of the indoor unit 3c is started while the indoor units 3a and 3b are operating at a low load as shown in Table 5 will be described.

[0036]

[Table 5]

According to Tables 3 and 5, the indoor units 3a, 3b, 3c
Are 0.8, 1.0 and 3.8, respectively.
Accordingly, the frequency Hz of the compressor 4 is similarly given by Hz = A × (0.8 + 1.0 + 3.8) = A × 5.6, and the frequency calculation result has not reached the allowable operation value of the compressor 4; A margin of about 30% is left, and the calculation result is sent to a compressor drive circuit (not shown) as a frequency signal to control the frequency of the compressor 4. Thereafter, calculation is performed from each of the rated capacity signals, the differential temperature signals, the operation mode signals, and the ON / OFF discrimination signals of the indoor units 3a, 3b, 3c at predetermined intervals, and if the loads of the indoor units 3a, 3b are the same. The frequency is continued until the indoor unit 3c reaches Ln = 7, and the calculation result is sent to a compressor drive circuit (not shown) as a frequency signal to control the frequency of the compressor 4.

The load on the indoor units 3a and 3b is Ln = 7.
In the case of, Hz = A × (2.0 + 2.5 + 3.8) = A × 8.3, which exceeds the allowable operating value of the compressor 4, and the frequency becomes Hz = A × 7.7. The frequency is transmitted to the compressor drive circuit as the allowable operation value of 4 to control the frequency of the compressor 4.

Next, the setting of the indoor air volume will be described. FIG.
FIG. 7 is an indoor fan speed setting diagram.

The air volume range that can be set by the user is, for example, five speeds of Hi, Me +, Me, Me-, and Lo as one example. Here, when the air conditioning load maximum zone signal is detected at the maximum Hi as the set air volume, the air volume setting is changed so that the air conditioning load maximum air volume setting PHi exceeds the Hi setting that cannot be set by the user through an external operation using a remote controller or the like. . And when the load of the indoor unit becomes Ln = 7,
Change to the original set airflow Hi.

Although the above description has been made mainly for cooling, heating can also be controlled similarly.

As described above, the capacity corresponding to the load is supplied to the indoor unit having a small load, and only the indoor unit in the maximum air-conditioning load zone is designed to have a capacity exceeding the rated capacity of the indoor unit. Since the compressor frequency and the indoor air volume are controlled so as to supply a sufficient outdoor capacity, the time until the set temperature is reached can be shortened, and the comfort can be improved and the energy can be saved.

Next, a second embodiment of the present invention will be described. Note that the refrigeration cycle in the second embodiment is the same as that in the first embodiment, and a description thereof will be omitted.
FIG. 6 is a time chart showing the correlation between the indoor load constant, the compressor frequency, and the indoor air flow according to the second embodiment of the present invention. As in the first embodiment, the second embodiment
Also, when the set air volume is the maximum Hi, the air conditioning load
When a large zone signal is detected, the user
Air conditioning load exceeding Hi setting that cannot be set by external operation due to
Change the air volume setting to achieve the maximum load air volume setting PHi.
U. This figure is different from the first embodiment in that even if an indoor unit detects a signal with a load constant of Ln = 8 and changes the compressor frequency, the indoor air volume is not changed to PHi at the same time.
The delay time is set such that the air volume setting is changed to PHi after the refrigeration cycle is stabilized by delaying the time by seconds. For this reason, it is obtained from the first embodiment.
In addition to the effects of cooling, the rapid rise of indoor air volume in cooling can prevent the path balance from breaking down and prevent fan condensation, and the heating can increase the indoor air volume without increasing the high pressure, resulting in a feeling of cool air and comfortable. It is possible to improve the quality such that the refrigerating property becomes extremely poor and the subcool is too large to form an appropriate refrigeration cycle.

Next, a third embodiment of the present invention will be described. Note that the refrigeration cycle in the third embodiment is the same as that in the first embodiment, and a description thereof will be omitted.
FIG. 7 is a time chart showing the correlation between the indoor load constant, the compressor frequency, and the indoor air flow according to the third embodiment of the present invention. As in the first embodiment, the second embodiment
Also, when the set air volume is the maximum Hi, the air conditioning load
When a large zone signal is detected, the user
Air conditioning load exceeding Hi setting that cannot be set by external operation due to
Change the air volume setting to achieve the maximum load air volume setting PHi.
U. The difference of this figure from the first embodiment is that when the load constant of an indoor unit changes from Ln = 8 to Ln = 7 and the air-conditioning load maximum zone is canceled, cooling will be described as an example at the same time. Then, the indoor set air volume is changed to FanNo19 (PH
From i) to FanNo12 (Hi), without any change, FanNo17 two tap down from FanNo1
For 10 seconds, and then repeats the same operation to set the air volume fanNo12 (Hi) before the air conditioning load is applied.
The purpose is to vary the indoor air volume. For this reason,
In addition to the functions and effects obtained from the first embodiment, it is possible to prevent a rapid decrease in the amount of airflow, eliminate the sense of incongruity in actual listening, and improve comfort.

Next, a fourth embodiment of the present invention will be described. Note that the refrigeration cycle in the fourth embodiment is the same as that in the first embodiment, and thus the description is omitted.
FIG. 8 is a time chart showing the correlation between the indoor load constant, the compressor frequency, and the indoor air flow according to the third embodiment of the present invention. As in the first embodiment, the second embodiment
Also, when the set air volume is the maximum Hi, the air conditioning load
When a large zone signal is detected, the user
Air conditioning load exceeding Hi setting that cannot be set by external operation due to
Change the air volume setting to achieve the maximum load air volume setting PHi.
U. This figure differs from the first embodiment in that when the load constant of a certain indoor unit changes from Ln = 7 to Ln = 8 and the elapsed time of Ln = 8 exceeds one hour, the differential temperature signal Is forced to be Ln even though Ln = 8
= 7 for releasing the air conditioning load maximum zone for a certain time (T1). For this reason, it can be obtained from the first embodiment.
In addition to the functions and effects that can be obtained, it is possible to prevent dew condensation around the blow-off and mist blowing caused by rinsing during cooling, thereby improving quality and comfort.

[0046]

As is clear from the above embodiment, the multi-room air conditioning system of the present invention detects the indoor temperature and the indoor temperature setting means capable of setting a desired indoor temperature for each indoor unit. An indoor temperature detecting means, and a differential temperature calculating means for calculating a differential temperature between the set indoor temperature and the indoor temperature from the indoor temperature setting means and the indoor temperature detecting means, and further defining a rated capacity of each of the indoor units. A capacity discriminating means for discriminating and an on / off discriminating means for discriminating whether the indoor unit is in operation or stopped is provided, a temperature range in which the temperature difference can be taken is divided into a plurality of temperature zones, and the temperature zone range is further divided. Within each of the indoor units is provided a rated air flow variable means and a rated air flow set value, and a load constant corresponding to an indoor load is determined for each temperature zone and for each rated capacity of the indoor unit. The cooling provided the air-conditioning load maximum zone below the predetermined temperature zone in the heating above a predetermined temperature zone,
Load constant storage means for determining and storing a load constant equal to or greater than the rated capacity for each rated capacity of the indoor unit is provided, and the differential temperature calculating means,
When calculating the compressor capacity at predetermined intervals using the data obtained from the capacity determination means, the on / off determination means, and the load constant storage means, when there is a differential temperature signal corresponding to the air conditioning load maximum zone even in one room. When the compressor capacity is less than the allowable operation value, the capacity is calculated using the load constant of the maximum air conditioning load zone obtained from the load constant storage means, and the capacity (frequency) variable compression is calculated based on this capacity value. The compressor capacity control means for controlling the capacity of the compressor is provided, and when the compressor capacity meets the operation allowance value, the compressor capacity control means is provided within a range of the operation allowance value. By performing the air volume variable control of each of the indoor units by using the air conditioning load maximum zone air volume set value that is not set in the rated air volume variable range such that the set air volume is larger than the obtained set value, For the indoor unit with a small load, the capacity corresponding to the load is supplied, and the compressor frequency is controlled so that the indoor unit with the maximum load is supplied with the extra outdoor capacity only until the set temperature is reached. Can be shortened, and comfort can be improved and energy can be saved.

In addition, even one room corresponds to the maximum air-conditioning load zone.
If there is a differential temperature signal, the compressor capacity is
Air conditioner is obtained from the load constant storage means.
The capacity calculated using the load constant of the load maximum zone,
Based on this capacity value, the capacity (frequency) variable type compressor
A compressor capacity control means for controlling the capacity of the compressor.
If the quantity meets the operation allowance, it is within the operation allowance
The compressor capacity control means is provided, and the rated air volume is further set.
If the set air volume is larger than the set value obtained from the value
Maximum air-conditioning load zone not set in the rated air flow variable range
The air volume variable control of each indoor unit is performed using the air volume set value.
If you do, set a delay time after the compressor capacity is changed.
It is what you do. Use the air-conditioning load maximum zone airflow setting value
By performing variable air volume control of each indoor unit, the load
For indoor units with a small number, provide the capacity according to the load.
Power supply, and provide sufficient outdoor capacity only for the indoor unit with the maximum load.
To control the compressor frequency to supply
Time to reach can be shortened, improving comfort
By performing a variable air volume control with a delay time after the compressor capacity is varied, it is possible to prevent the path balance from being lost due to the rapid indoor air volume increase and to cause fan condensation due to rapid indoor air volume increase. Preventing or increasing the indoor air volume without raising the high pressure during heating prevents a feeling of cool air, which significantly deteriorates comfort and prevents excessive subcools from forming an appropriate refrigeration cycle. , Quality can be improved.

In addition, even one room corresponds to the maximum air conditioning load zone.
If there is a differential temperature signal, the compressor capacity is
Air conditioner is obtained from the load constant storage means.
The capacity calculated using the load constant of the load maximum zone,
Based on this capacity value, the capacity (frequency) variable type compressor
A compressor capacity control means for controlling the capacity of the compressor.
If the quantity meets the operation allowance, it is within the operation allowance
The compressor capacity control means is provided, and the rated air volume is further set.
If the set air volume is larger than the set value obtained from the value
Maximum air-conditioning load zone not set in the rated air flow variable range
The air volume variable control of each indoor unit is performed using the air volume set value.
In addition to performing air volume variable control of each indoor unit,
The maximum load adjustment zone is released and the air volume increases
When the air flow falls below the rated air flow variable range
While maintaining the fixed time, gradually reduce the air volume and
The variable air volume control is performed so that the air volume is set. Sky
The maximum load of the indoor unit using
By performing variable air volume control, indoor units with small loads can be controlled.
Supply the capacity corresponding to the load, and
Compressor circumference to supply extra outdoor capacity to indoor units only
To control the wave number, set the time to reach the set temperature.
Faster, improved comfort and energy saving
While performing the air volume variable control of each indoor unit, when the air conditioning load maximum zone is released and the air volume falls from the air conditioning load maximum zone air volume set value to the rated air volume variable range, while maintaining a certain time, By performing the air volume variable control so as to reduce the air volume stepwise so that the air volume becomes a predetermined set air volume, it is possible to prevent a rapid air volume reduction and eliminate a sense of incongruity that is actually heard, thereby improving comfort.

Also, even one room corresponds to the maximum air conditioning load zone.
If there is a differential temperature signal, the compressor capacity is
Air conditioner is obtained from the load constant storage means.
The capacity calculated using the load constant of the load maximum zone,
Based on this capacity value, the capacity (frequency) variable type compressor
A compressor capacity control means for controlling the capacity of the compressor.
If the quantity meets the operation allowance, it is within the operation allowance
The compressor capacity control means is provided, and the rated air volume is further set.
If the set air volume is larger than the set value obtained from the value
Maximum air-conditioning load zone not set in the rated air flow variable range
The air volume variable control of each indoor unit is performed using the air volume set value.
The difference temperature signal corresponding to the air conditioning load maximum zone
Time lapse storage means for storing the time lapse since the detection of
With the data obtained from the time lapse storage means.
Control compressor capacity control and indoor air volume control with time limit
Things. Using the air conditioning load maximum zone airflow setting value
Note that by performing variable air volume control of each indoor unit,
Supply the capacity according to the load to
Supply extra room capacity only to the indoor unit with the maximum load
To reach the set temperature in order to control the compressor frequency
Time to get to work faster, improving comfort and
And time lapse storage means for storing the time lapse since the detection of the temperature difference signal corresponding to the air conditioning load maximum zone, and using the data obtained from the time lapse storage means. By controlling the compressor capacity control and indoor air volume control with a time limit, it is possible to prevent dew condensation around the blow-off and mist blowing phenomenon due to rinsing during cooling, and improve quality and comfort. .

[Brief description of the drawings]

FIG. 1 is a refrigeration cycle diagram of the multi-room air conditioning system of the present invention.

FIG. 2 is a control block diagram of a compressor frequency in the embodiment.

FIG. 3 is a temperature zone division diagram of a differential temperature ΔT of a conventional example.

FIG. 4 is a temperature zone division diagram of a temperature difference ΔT in the first embodiment.

FIG. 5 is an indoor fan speed setting diagram in the first embodiment.

FIG. 6 is a time chart illustrating a correlation between an indoor load constant, a compressor frequency, and an indoor air flow according to the second embodiment.

FIG. 7 is a time chart showing a correlation between an indoor load constant, a compressor frequency, and an indoor air flow according to a third embodiment.

FIG. 8 is a time chart showing a correlation between an indoor load constant, a compressor frequency, and an indoor air flow according to a fourth embodiment.

FIG. 9 is a correlation diagram between indoor unit load and compressor frequency.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outdoor unit 2 Branching machine 3a, 3b, 3c Indoor unit 4 Compressor 5 Outdoor heat exchanger 6 Four-way valve 7 Electric expansion valve 8a, 8b, 8c Indoor heat exchanger 9 Liquid side main pipe 10a, 10b, 10c Liquid side branch pipe 11a, 11b, 11c Electric expansion valve 12a, 12b, 12c Gas-side branch pipe 13 Gas-side main pipe 14 Suction pipe 15 Bypass circuit 16 Auxiliary throttle 17a, 17b, 17c Suction temperature sensor 18 Saturation temperature sensor 19 Suction temperature sensor 20a, 20b 20c pipe temperature sensor

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-62-225842 (JP, A) JP-A-1-208644 (JP, A) JP-A-2-64341 (JP, A) JP-A-1- 269872 (JP, A) JP-A-4-20734 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F24F 11/02 102

Claims (4)

(57) [Claims] 1. A capacity (frequency) variable compressor, a four-way valve,
One outdoor unit having an outdoor heat exchanger, and a plurality of indoor units having an indoor heat exchanger, a liquid-side branch pipe provided in the outdoor unit and branching a liquid-side main pipe through which a refrigerant liquid mainly flows, and A motor-operated expansion valve which is provided in the outdoor unit and is connected to a gas-side main pipe through which a gas-side main pipe through which refrigerant gas mainly flows is branched, so that a valve opening can be electrically controlled for each of the liquid-side branch pipes. A refrigeration cycle is configured by interposing a room temperature, and an indoor temperature setting unit that can set a desired indoor temperature and an indoor temperature detection unit that detects an indoor temperature are provided in each of the indoor units. A differential temperature calculating means for calculating a temperature difference between the set indoor temperature and the indoor temperature from the indoor temperature detecting means, and a capacity determining means for determining a rated capacity of each of the indoor units, and an operation of each of the indoor units. Whether it is stopped or stopped A temperature range in which the temperature difference can be obtained is divided into a plurality of temperature zones, and a rated air volume variable device and a rated air volume set value are provided for each of the indoor units within the temperature zone range. A load constant corresponding to the indoor load is determined for each temperature zone and for each rated capacity of the indoor unit, and an air conditioning load maximal zone of a predetermined temperature zone or less for cooling is provided for a predetermined temperature zone or more for cooling,
Load constant storage means for determining and storing a load constant equal to or greater than the rated capacity for each rated capacity of the indoor unit is provided, and the differential temperature calculating means,
When calculating the compressor capacity at predetermined intervals using the data obtained from the capacity determination means, the on / off determination means, and the load constant storage means, when there is a differential temperature signal corresponding to the air conditioning load maximum zone even in one room. When the compressor capacity is less than the allowable operation value, the capacity is calculated using the load constant of the maximum air conditioning load zone obtained from the load constant storage means, and the capacity (frequency) variable compression is calculated based on this capacity value. The compressor capacity control means for controlling the capacity of the compressor is provided, and when the compressor capacity meets the operation allowance value, the compressor capacity control means is provided within a range of the operation allowance value. It is characterized in that the air volume variable control of each of the indoor units is performed using the airflow load maximum zone air volume set value which is not set in the rated air volume variable region where the set air volume becomes larger than the obtained set value. Multi-room air conditioning system according to. 2. A set value obtained from a rated air flow set value.
Set the rated airflow variable range so that the set airflow becomes large.
Are each have use have not the air conditioning load maximum zone air volume set value
When performing variable air volume control of indoor units, the compressor capacity is variable.
After that, a delay time is provided to perform the operation.
2. The multi-room air conditioning system according to 1. 3. An air volume variable control of each indoor unit is performed, and
The maximum load adjustment zone is released and the air volume increases
When the air flow falls below the rated air flow variable range
While maintaining the fixed time, gradually reduce the air volume and
It is characterized by performing air volume variable control so as to reach the set air volume.
The multi-room air conditioning system according to claim 1. 4. A temperature difference signal corresponding to an air-conditioning load maximum zone.
Time lapse storage means for storing the time lapse since the detection of
With the data obtained from the time lapse storage means.
Control compressor capacity control and indoor air volume control with time limit
The multi-chamber air conditioning system according to claim 1, wherein
M