JP3275669B2 - Multi-room air conditioning system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve comfortable environment and attain energy saving state by a method wherein in the case that a capability of an outdoor device has a surplus for an indoor device, while a maximum load is supplied to the indoor device, the surplus capacity is supplied to the indoor device of maximum load. SOLUTION: In the case that a capacity of a compressor is calculated for every predetermined period under application of data obtained through a difference temperature calculating circuit 2, a rated capacity memory circuit 5, an ON-OFF discriminating circuit 4 and a load constant table 10 and further in the case that there is a difference temperature signal corresponding to a maximum air conditioning load zone even in one room and a capacity of the compressor is not fulfilled up to an operation allowable value, it is calculated by applying a load constant in the maximum air conditioning load obtained by the load constant memory means. Then, there is provided a compressor capacity control means for use in controlling a capacity of a capacity (frequency) variable type compressor, and also there is provided a valve opening degree control means for calculating a degree of opening of each of electrical expansion valves connected to an indoor device being operated for every predetermined period under application of the aforesaid data and data obtained by the memory means for storing an initial degree of opening of the aforesaid valve and for controlling a degree of opening of the electrical expansion valve in response to a result of this calculation.

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 in which the compressor capacity is controlled by comparing the capacity of an outdoor unit and the capacity of each indoor unit, and the flow rate of refrigerant to each indoor unit is controlled (for example, Japanese Patent Application Laid-Open No. Hei 6-1994).
-257827).

Hereinafter, the conventional multi-room air conditioning system will be described with reference to the drawings.

FIG. 9 is a refrigeration cycle diagram of a conventional multi-room air conditioning system. This multi-room air conditioning system is configured by connecting one indoor unit 20 to a plurality of indoor units, in this example, three indoor units 21a, 21b, 21c. An inverter-driven frequency variable compressor 22 (hereinafter simply referred to as a compressor), an outdoor heat exchanger 2
3. A four-way valve 24 for switching between air conditioning and heating is provided, and the indoor heat exchangers 25 are provided in the indoor units 21a, 21b and 21c, respectively.
a, 25b, and 25c are provided. The outdoor unit 20 and the indoor units 21a, 21b, 21c are connected to the liquid side branch pipe 2 branched from the liquid side main pipe 26 provided in the outdoor unit 20.
7a, 27b, 27c and gas side branch pipes 29a, 29b branched from a gas side main pipe 28 provided in the outdoor unit 20;
29c. Liquid side branch pipe 27a, 27
b and 27c have electric expansion valves 30a, 30b, 3
On the liquid side main pipe 26, a receiver 31 capable of storing the refrigerant liquid is provided, and an auxiliary throttle 32 is provided for maintaining the receiver 31 at an intermediate pressure for cooling and heating. Further, a bypass circuit 34 for connecting the receiver 31 and the suction pipe 33 to the compressor 22 is provided, and the bypass circuit 34 is provided with an auxiliary throttle 35. In addition, each indoor unit 21
a, 21b, and 21c include indoor temperature sensors 36a, 36b, and 36 that detect the room temperature of the room where each indoor unit is installed.
c and an operation setting circuit 37 which can set an operation mode (cooling or heating) desired by the occupant, room temperature, operation and stop.
a, 37b and 37c are provided.

In this refrigeration cycle, during cooling, the refrigerant discharged from the compressor 22 flows from the four-way valve 24 to the outdoor heat exchanger 23 where it exchanges heat with outdoor air to condense and liquefy, and the auxiliary throttle 32 The pressure is reduced to an intermediate pressure. Then, a part of the liquid refrigerant is stored in the receiver 31, and the rest branches to the liquid side branch pipes 27a, 27b, 27c. The valve opening of the electric expansion valves 30a, 30b, 30c is controlled by a control method described later so as to be an opening corresponding to the load of each room, so that the refrigerant also has a low pressure at a flow rate corresponding to each load. After flowing into the indoor heat exchangers 25a, 25b, 25c and evaporating, the gas-side branch pipes 29a, 29b, 29
c, the gas passes through the gas-side main pipe 28 and the four-way valve 24 and is sucked into the compressor 22 again. Also, a very small amount of liquid refrigerant flows from the receiver 31 to the bypass circuit 34, and the auxiliary throttle 35
And flows to the suction pipe 33. 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 22 switches the four-way valve 24 to branch from the gas-side main pipe 28 to the gas-side branch pipes 29a, 29b, 29c, and the indoor heat exchangers 25a, 25b, 25c. , And condensed and liquefied, and the electric expansion valves 30a, 3a on the liquid side branch pipes 27a, 27b, 27c
The pressure is reduced at 0b and 30c to an intermediate pressure. Electric expansion valve 3
The opening degrees of the valves 0a, 30b, and 30c are controlled to the opening degrees corresponding to the loads of the respective rooms by a control method described later in the same manner as during cooling, so that the refrigerant also has a flow rate corresponding to the room heat exchanger 25a, It flows through 25b and 25c. In the refrigerant having the intermediate pressure, a part of the liquid refrigerant is stored in the receiver 31, and the remaining refrigerant is reduced in pressure by the auxiliary throttle 32 to have a low pressure, so that the outdoor heat exchanger 2
After passing through 3 and evaporating, it passes through the four-way valve 24 and is sucked into the compressor 22 again. Also, a very small amount of liquid refrigerant flows from the receiver 31 to the bypass circuit 34, and the auxiliary throttle 35
And flows to the suction pipe 33. 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 for controlling the compressor frequency and the electric expansion valve opening will be described. FIG. 10 is a block diagram showing a flow of control of the compressor frequency and the electric expansion valve opening, and FIG. 11 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 21a, the output of the indoor temperature sensor 36a is sent from the indoor temperature detecting circuit 41 to the differential temperature calculating circuit 42 as a temperature signal.
In step 3, the set temperature and the operation mode set by the operation setting circuit 37a are determined and sent to the temperature difference calculation circuit 42, where the temperature difference ΔT (= Tr−Ts) is calculated, and the load number shown in FIG. The value is converted into an Ln value and is used as a differential temperature signal. For example, during cooling operation, Tr = 27.3 ° C., Ts = 26 ° C.
Then, Ln = 6 at the temperature difference ΔT = 1.3 ° C. The ON-OFF determination circuit 44 operates (ON) or stops (O) the indoor unit 21a set by the operation setting circuit 37a.
FF), and further stores the rated capacity of the indoor unit 21a in the rated capacity storage circuit 45, and outputs the rated capacity signal, the differential temperature signal, the operation mode signal, and the ON-OFF determination signal from the signal transmission circuit 46. Signal receiving circuit 47 of outdoor unit 20
Send to A similar signal is sent from the indoor units 21b and 21c to the signal receiving circuit 47. The signal received by the signal receiving circuit 47 is transmitted to a compressor frequency calculating circuit 48 and an expansion valve opening calculating circuit 4.
9 is sent.

In the compressor frequency calculation circuit 48, the indoor unit 21
The load constants are read from the load constant table 50 shown in Table 1 below from the rated capacity signals, the differential temperature signals, the operation mode signals, and the ON / OFF discrimination signals of a, 21b, and 21c, and the sum of the load constants is multiplied by the constant. Thus, the frequency of the compressor 22 is determined.

[0011]

[Table 1]

As an example, the indoor units 21a, 21b, 21
The case where the signal from c is as shown in Table 2 below will be described.

[0013]

[Table 2]

From Tables 1 and 2, the indoor units 21a, 21b,
The load constants of the compressor 21c are 1.5, 1.0, and 1.9, respectively, and the frequency Hz of the compressor 22 is as follows: where A is a constant, Hz = A × (1.5 + 1.0 + 1.9) = A × 4 .4, the result of this operation is sent to the compressor drive circuit as a frequency signal to control the frequency of the compressor 22. Thereafter, the rated capacity signal, the differential temperature signal, the operation mode signal, the ON-OF signal of each of the indoor units 21a, 21b, 21c are provided at predetermined intervals.
Calculation is performed from the F determination signal, and the calculation result is sent to the compressor drive circuit as a frequency signal to control the frequency of the compressor 22.

Similarly, in the expansion valve opening calculating circuit 49, the load constant from the load constant table 50 is obtained from the rated capacity signal, the differential temperature signal, the operation mode signal, and the ON-OFF discrimination signal of each of the indoor units 21a, 21b, 21c. Then, it is read out from the valve initial opening degree table 51 from the rated capacity of each of the indoor units 21a, 21b, 21c. Note that the valve initial opening is determined so that each indoor unit can perform a predetermined capacity control even with a combination of indoor units having different rated capacities.

The valve opening of the electric expansion valves 30a, 30b and 30c is obtained by dividing each load constant by a predetermined value of the load constant and multiplying the result by the initial valve opening. This calculation result is sent to an expansion valve drive circuit (not shown) as an expansion valve opening signal.

The output of the suction temperature sensor 38 is used as a temperature signal by the suction temperature detection circuit 52 as a superheat degree calculation circuit 53.
The output of the saturation temperature sensor 39 is sent from the saturation temperature detection circuit 54 as a temperature signal to the superheat calculation circuit 53, where the superheat SH (suction temperature-saturation temperature) is calculated to calculate the expansion valve opening. It is sent to the circuit 49. The expansion valve opening calculation circuit 49 calculates the number of pulses for changing the valve opening in accordance with the degree of superheat SH sent, and calculates the electric expansion valves 30a, 30b,
The signal is sent to a drive circuit (not shown) of 30c and controlled.

As described above, since the compressor frequency is controlled in accordance with the total required capacity of each room, and the opening degree of each electric expansion valve is determined in accordance with the load in each room, necessary capacity is required. It can be allocated to a comfortable room, and can improve comfort and save energy.

[0019]

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 21
If the differential temperature signals are both Ln = 6 and the rated capacities of the indoor units 21a and 21b are the same as those in Table 2 when the operation of the compressors a and 21b is started at the same time, the frequency Hz of the compressor 22 becomes
Hz = A × (2.0 + 2.5) = A × 4.5. The difference temperature signals of the indoor units 21a, 21b, 21c are all Ln =
6, Hz = A × (2.0 + 2.5 + 3.
2) = A × 7.7, and assuming that this is a permissible operating value of the compressor 22, 4.5 / 7.7 = 0.58, leaving about 40% of room. That is, while the indoor units 21a and 21b are in the maximum load state and request the outdoor unit 20 to have the maximum capacity of the indoor unit, the outdoor unit 2
0 indicates that the indoor units 21a and 21
This means that the refrigerant is supplied to b. 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 20 has a capacity margin, and much time is required to reach the set temperature. I needed it.

Further, the same problem occurs even when the indoor unit 21c starts operating under the maximum load state while the indoor units 21a and 21b are operating 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 20 in the presence of the indoor unit with 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 a sufficient outdoor capacity only to an indoor unit having a maximum load without supplying a capacity exceeding a required capacity to an indoor unit having a small load. The purpose is to improve comfort and save energy.

[0024]

In order to solve the above-mentioned problems, a multi-room air conditioning system according to the present invention has a capacity (frequency).
A liquid-side main pipe in which one outdoor unit having a variable compressor, a four-way valve, and an outdoor heat exchanger, and a plurality of indoor units having an indoor heat exchanger are provided in the outdoor unit, and mainly a refrigerant liquid flows. The liquid side branch pipe and the gas side main pipe, which is provided in the outdoor unit and mainly flows the refrigerant gas, are connected via the branched gas side branch pipe, and the valve opening is electrically connected to each of the liquid side branch pipes. A refrigeration cycle is configured by interposing an electric expansion valve capable of controlling the indoor temperature, and an indoor temperature setting means capable of setting a desired indoor temperature and an indoor temperature detecting means detecting the indoor temperature are provided for each of the indoor units. A temperature difference calculating means for calculating a temperature difference between the set indoor temperature and the indoor temperature from the indoor temperature setting means and the indoor temperature detecting means, a capacity determining means for determining a rated capacity of each of the indoor units, and Operate for each of the indoor units On / off determining means for determining whether the temperature difference is possible is divided into a plurality of temperature zones, and a load corresponding to the indoor load for each temperature zone and for each rated capacity of the indoor unit is provided. In addition to defining constants, a maximum air-conditioning load zone is provided for cooling, which is equal to or higher than a predetermined temperature zone and for heating, which is equal to or lower than a predetermined temperature zone. A valve initial opening storage means for determining and storing a valve initial opening for each rated capacity of the indoor unit, and being obtained from the differential temperature calculating means, the capacity determining means, the on / off determining means, and the load constant storing means. When calculating the compressor capacity for each predetermined cycle using the data, if there is a load constant corresponding to the maximum air conditioning load zone even in one room, and if the compressor capacity is less than the allowable operation value, the negative Compressor capacity control means for controlling the capacity of the variable capacity (frequency) compressor based on the capacity value calculated using the load constant of the air conditioning load maximum zone obtained from the constant storage means; Using the data and the data obtained from the valve initial opening storage means, the valve opening of each electric expansion valve connected to the operating indoor unit is calculated at predetermined intervals, and the electric expansion is calculated based on the calculation result. A valve opening control means for controlling the valve opening of the valve is provided.

Further, another multi-room air conditioning system according to the present invention provides a single outdoor unit having a variable capacity (frequency) compressor, a four-way valve, and 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 the refrigerant liquid mainly flows, and a gas side provided in the outdoor unit and branching a gas-side main pipe through which the refrigerant gas mainly flows. A refrigeration cycle is configured by connecting via a branch pipe and interposing an electric expansion valve capable of electrically controlling the valve opening degree in each of the liquid side branch pipes, and setting a desired one in each of the indoor units. An indoor temperature setting means capable of setting an indoor temperature and an indoor temperature detecting means for detecting an indoor temperature are provided, and a difference between the set indoor temperature and the indoor temperature is calculated from the indoor temperature setting means and the indoor temperature detecting means. Temperature calculating means, and further each of the indoor units A capacity discriminating means for discriminating a rated capacity and an on / off discriminating means for discriminating whether the indoor unit is operating or stopped are provided, and a temperature range in which the temperature difference can be taken is divided into a plurality of temperature zones, A load constant corresponding to the indoor load is determined for each zone and for each rated capacity of the indoor unit.
In heating, an air conditioning load maximum zone below a predetermined temperature zone is provided, and a load constant storage means for determining and storing a differential temperature signal indicating that the indoor unit is in the air conditioning load maximum zone is provided for each rated capacity of the indoor unit. A valve initial opening storage means for determining and storing a valve initial opening for each is provided, and a predetermined period is set 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 calculating the compressor capacity every time, even if 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 compressor capacity is in the air conditioning load maximum zone by an approximate expression. A load constant calculating means for calculating a load constant value of the indoor unit is provided, a compressor capacity is calculated using the data and the data of the load constant obtained by the load constant calculating means, and a compressor capacity is calculated based on the calculation result. It is provided with a compressor capacity control means for controlling the volume of serial volume (frequency) deformable compressor.

Another multi-room air conditioning system according to the present invention comprises a single outdoor unit having a variable capacity (frequency) compressor, a four-way valve, and 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 the refrigerant liquid mainly flows, and a gas side provided in the outdoor unit and branching a gas-side main pipe through which the refrigerant gas mainly flows. A refrigeration cycle is configured by connecting via a branch pipe and interposing an electric expansion valve capable of electrically controlling the valve opening degree in each of the liquid side branch pipes, and setting a desired one in each of the indoor units. An indoor temperature setting means capable of setting the indoor temperature and an indoor temperature detecting means for detecting the indoor temperature are provided, and a difference between the set indoor temperature and the indoor temperature is calculated from the indoor temperature setting means and the indoor temperature detecting means. Temperature calculating means, and further each of the indoor units A capacity discriminating means for discriminating a rated capacity and an on / off discriminating means for discriminating whether the indoor unit is operating or stopped are provided, and a temperature range in which the temperature difference can be taken is divided into a plurality of temperature zones, A load constant corresponding to the indoor load is determined for each zone and for each rated capacity of the indoor unit.
In heating, an air conditioning load maximum zone below a predetermined temperature zone is provided, and a load constant storage means for determining and storing a differential temperature signal indicating that the indoor unit is in the air conditioning load maximum zone for each rated capacity is provided, When calculating the compressor capacity at predetermined intervals using data obtained from the capacity determination means, the on / off determination means, and the load constant storage means, there is a differential temperature signal corresponding to an air conditioning load maximum zone even in one room. In such a case, when the compressor capacity is less than the allowable operation value, a load constant calculating means for calculating a load constant value of the indoor unit in the maximum air conditioning load zone from the compressor margin is provided, and the data and the load constant calculating means are used. Compressor capacity control means for calculating the compressor capacity using the obtained load constant data and controlling the capacity of the variable capacity (frequency) compressor based on the calculation result. Those digits.

Another multi-room air conditioning system according to the present invention comprises a single outdoor unit having a variable capacity (frequency) compressor, a four-way valve, and 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 the refrigerant liquid mainly flows, and a gas side provided in the outdoor unit and branching a gas-side main pipe through which the refrigerant gas mainly flows. A refrigeration cycle is configured by connecting via a branch pipe and interposing an electric expansion valve capable of electrically controlling the valve opening degree in each of the liquid side branch pipes, and setting a desired one in each of the indoor units. An indoor temperature setting means capable of setting an indoor temperature and an indoor temperature detecting means for detecting an indoor temperature are provided, and a difference between the set indoor temperature and the indoor temperature is calculated from the indoor temperature setting means and the indoor temperature detecting means. Temperature calculating means, and further each of the indoor units A capacity discriminating means for discriminating a rated capacity and an on / off discriminating means for discriminating whether the indoor unit is operating or stopped are provided, and a temperature range in which the temperature difference can be taken is divided into a plurality of temperature zones, A load constant corresponding to the indoor load is determined for each zone and for each rated capacity of the indoor unit.
In heating, a maximum air conditioning load zone below a predetermined temperature zone is provided, and a load constant storage means is provided for determining and storing a temperature difference signal indicating that the indoor unit is in the maximum air conditioning load zone for each rated capacity of the indoor unit, and providing a state of the refrigeration cycle. Providing a refrigeration cycle data detecting means for detecting, when calculating the compressor capacity at predetermined intervals using data obtained from the differential temperature calculating means, the capacity determining means, the on / off determining means, the load constant storing means. If there is a differential temperature signal corresponding to the maximum air conditioning load zone even in one room, and the compressor capacity is less than the allowable operating value, the compression is performed to approach the refrigeration cycle data control target value according to the number of operating indoor units. A compressor capacity control means for calculating the capacity of the compressor and controlling the capacity of the variable capacity (frequency) compressor based on the calculation result is provided.

Further, another multi-room air conditioning system according to the present invention comprises a single outdoor unit having a variable capacity (frequency) compressor, a four-way valve, and 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 the refrigerant liquid mainly flows, and a gas side provided in the outdoor unit and branching a gas-side main pipe through which the refrigerant gas mainly flows. A refrigeration cycle is configured by connecting via a branch pipe and interposing an electric expansion valve capable of electrically controlling the valve opening degree in each of the liquid side branch pipes, and setting a desired one in each of the indoor units. An indoor temperature setting means capable of setting an indoor temperature and an indoor temperature detecting means for detecting an indoor temperature are provided, and a difference between the set indoor temperature and the indoor temperature is calculated from the indoor temperature setting means and the indoor temperature detecting means. Temperature calculating means, and further each of the indoor units A capacity discriminating means for discriminating a rated capacity and an on / off discriminating means for discriminating whether each of the indoor units is in operation or stopped, dividing a temperature range in which the temperature difference can be taken into a plurality of temperature zones, A load constant calculating means for calculating a load constant of each indoor unit by an approximate expression using the data, calculating a compressor capacity, and based on the calculation result, the capacity (frequency) variable type compressor; The compressor capacity control means for controlling the capacity of the compressor is provided.

In another multi-room air conditioning system according to the present invention, for each of the indoor units during and after operation, the load constant and load corresponding to the rated capacity and the current differential temperature are stored in the load constant storage means. The predetermined value of the constant is read out, the valve opening degree corresponding to the rated capacity is read out from the valve opening degree storage means, and even if there is a load constant corresponding to the air-conditioning load maximum zone even in one room, the compressor capacity becomes the allowable operating value. Is less than the value, the valve opening of the electric expansion valve connected to the indoor unit in the maximum air conditioning load zone is calculated as the product of the reciprocal of a predetermined value of the load constant, the load constant calculated by the load constant calculating means, and the valve initial opening. , A valve opening control means for controlling so as to be a value of the product.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention operates as follows by the above means.

That is, each of the indoor units is provided with an indoor temperature setting means for setting a desired indoor temperature and an indoor temperature detecting means for detecting the indoor temperature. A differential temperature calculating means for calculating a temperature difference between the indoor temperature and the indoor temperature; a capacity determining means for determining a rated capacity of each of the indoor units; and determining whether each of the indoor units is operating or stopped. On / off determining means is provided, the temperature range in which the temperature difference can be taken is divided into a plurality of temperature zones, and a load constant corresponding to an indoor load is determined for each temperature zone and for each rated capacity of the indoor unit. Provide a maximum air conditioning load zone equal to or higher than the predetermined temperature zone and lower than the predetermined temperature zone for heating,
Providing 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, and providing valve initial opening storage means for determining and storing a valve initial opening for each rated capacity of the indoor unit, When calculating the compressor capacity 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, even one room corresponds to the air-conditioning load maximum zone. When there is a load constant and the compressor capacity is less than the allowable operation value, the capacity is calculated using the load constant of the air conditioning load maximum zone obtained from the load constant storage means, and the capacity is calculated based on the capacity value. (Frequency) Compressor capacity control means for controlling the capacity of the variable-type compressor is provided, and is connected to an operating indoor unit at predetermined intervals using the data and the data obtained from the valve initial opening degree storage means. By calculating the valve opening degree of each of the electric expansion valves obtained, and providing the valve opening degree control means for controlling the valve opening degree of the electric expansion valve based on the calculation result, the indoor unit having a small load is provided. In order to supply the capacity according to the load, and to control the compressor frequency so as to supply the extra outdoor capacity only to the indoor unit at the maximum load, the time until the set temperature is reached can be shortened. It is possible to improve comfort and save energy.

Each of the indoor units is provided with an indoor temperature setting means for setting a desired indoor temperature and an indoor temperature detecting means for detecting the indoor temperature. The indoor temperature setting means and the indoor temperature detecting means are used for setting. A differential temperature calculating means for calculating a temperature difference between the indoor temperature and the indoor temperature; a capacity determining means for determining a rated capacity of each of the indoor units; and determining whether each of the indoor units is operating or stopped. On / off determining means is provided, the temperature range in which the temperature difference can be taken is divided into a plurality of temperature zones, and a load constant corresponding to an indoor load is determined for each temperature zone and for each rated capacity of the indoor unit. Provide a maximum air-conditioning load zone equal to or higher than a predetermined temperature zone and a predetermined temperature zone or less for heating, and determine a differential temperature signal indicating that the air conditioner is in the maximum air-conditioning load zone for each rated capacity of the indoor unit. A load constant storing means for storing the temperature difference, 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 maximum air conditioning load zone in the room, and the compressor capacity is less than the allowable operation value, the load constant for calculating the load constant value of the indoor unit in the maximum air conditioning load zone using an approximate expression Calculating means for calculating a compressor capacity using the data and the load constant data obtained by the load constant calculating means, and controlling a capacity of the variable capacity (frequency) compressor based on the calculation result. By providing the compressor capacity control means, the load constant value of the indoor unit in the maximum air conditioning load zone is obtained by an approximate expression using the rated capacity of the indoor unit and the differential temperature data, and the compressor frequency is obtained. Gosuru Therefore, it is possible fine load correspondence, it is possible to quickly the time to reach the set temperature, it is possible to improve and energy saving comfort.

Each of the indoor units is provided with an indoor temperature setting means for setting a desired indoor temperature and an indoor temperature detecting means for detecting the indoor temperature. The indoor temperature setting means and the indoor temperature detecting means are used for setting. A differential temperature calculating means for calculating a temperature difference between the indoor temperature and the indoor temperature; a capacity determining means for determining a rated capacity of each of the indoor units; and determining whether each of the indoor units is operating or stopped. On / off determining means is provided, the temperature range in which the temperature difference can be taken is divided into a plurality of temperature zones, and a load constant corresponding to an indoor load is determined for each temperature zone and for each rated capacity of the indoor unit. Provide a maximum air-conditioning load zone equal to or higher than a predetermined temperature zone and a predetermined temperature zone or less for heating, and determine a differential temperature signal indicating that the air conditioner is in the maximum air-conditioning load zone for each rated capacity of the indoor unit. A load constant storing means for storing the temperature difference, 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 the room, and the compressor capacity is less than the allowable operating value, the load constant for calculating the load constant value of the indoor unit in the air conditioning load maximum zone from the compressor margin Calculating means for calculating a compressor capacity using the data and the load constant data obtained by the load constant calculating means, and controlling a capacity of the variable capacity (frequency) compressor based on the calculation result. By providing the compressor capacity control means, the load constant of the indoor unit in the air-conditioning load maximum zone is added by multiplying the compressor capacity margin, so that the margin of the compression function power is considered. Margin capacity can be effectively utilized, it is possible more granular load correspondence, it is possible to quickly the time to reach the set temperature, it is possible to improve and energy saving comfort.

Each of the indoor units is provided with an indoor temperature setting means for setting a desired indoor temperature and an indoor temperature detecting means for detecting the indoor temperature. The indoor temperature setting means and the indoor temperature detecting means are used for setting. A differential temperature calculating means for calculating a temperature difference between the indoor temperature and the indoor temperature; a capacity determining means for determining a rated capacity of each of the indoor units; and determining whether each of the indoor units is operating or stopped. On / off determining means is provided, the temperature range in which the temperature difference can be taken is divided into a plurality of temperature zones, and a load constant corresponding to an indoor load is determined for each temperature zone and for each rated capacity of the indoor unit. Provide a maximum air-conditioning load zone equal to or higher than a predetermined temperature zone and a predetermined temperature zone or less for heating, and determine a differential temperature signal indicating that the air conditioner is in the maximum air-conditioning load zone for each rated capacity of the indoor unit. Providing a load constant storage means for storing, and a refrigeration cycle data detection means for detecting a state of the refrigeration cycle, and storing data obtained from the differential temperature calculation means, the capacity determination means, the on / off determination means, and the load constant storage means. When the compressor capacity is calculated for each predetermined cycle using the temperature difference signal corresponding to the maximum air-conditioning load zone even in one room, if the compressor capacity is less than the operation allowable value, the number of indoor units operated is reduced. Accordingly, the compressor capacity is calculated so as to approach the control target value of the refrigeration cycle data, and compressor capacity control means for controlling the capacity of the capacity (frequency) variable compressor based on the calculation result is provided. If there is an indoor unit in the maximum air-conditioning load zone, the compressor must be operated in accordance with the number of operating indoor units to control the compressor frequency using the refrigeration cycle data as the control target value. Without having to load state, it is possible fine load correspondence, it is possible to quickly the time to reach the set temperature, it is possible to improve and energy saving comfort.

Each of the indoor units is provided with an indoor temperature setting means for setting a desired indoor temperature and an indoor temperature detecting means for detecting the indoor temperature. A differential temperature calculating means for calculating a temperature difference between the indoor temperature and the indoor temperature; a capacity determining means for determining a rated capacity of each of the indoor units; and determining whether each of the indoor units is operating or stopped. Load constant calculating means for providing an on / off determining means, dividing a temperature range in which the temperature difference can be taken into a plurality of temperature zones, and calculating a load constant of each indoor unit by an approximate expression using the data at predetermined intervals. Is provided, and compressor capacity control means for controlling the capacity of the variable capacity (frequency) compressor based on the calculation result is provided, so that the load constant of each indoor unit is reduced. Calculated by an approximate formula from the number of operating internal units, their respective rated capacities, and each room temperature difference signal, it is possible to respond more finely to the load and shorten the time required to reach the set temperature. Therefore, it is possible to improve comfort and save energy. Further, since a load constant table is not required, it is not necessary to increase the capacity of the storage circuit even if the number of indoor units increases.

Further, for each of the indoor units during and after operation, the rated capacity and the load constant corresponding to the current differential temperature and a predetermined value of the load constant are read out from the load constant storage means, and the valve initial opening degree storage means is read out. Read the initial valve opening corresponding to the rated capacity and read the indoor unit in the maximum air-conditioning load zone when the compressor capacity is less than the allowable operating value if there is a load constant corresponding to the maximum air-conditioning load zone even in one room. The valve opening for controlling the valve opening of the electric expansion valve connected to the valve as a product of the reciprocal of a predetermined value of the load constant, the load constant calculated by the load constant calculating means and the valve initial opening, and the value of this product. By providing the control means, even if the load of the indoor unit is in the maximum air conditioning load zone, if there is a margin in the capacity of the compressor, the extra room is utilized for the indoor unit in the maximum air conditioning load zone. The compressor frequency is controlled to supply the capacity of the compressor, and the opening of the electric expansion valve is controlled in accordance with the capacity. Time can be shortened, and comfort can be improved and energy can be saved.

[0037]

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

The refrigeration cycle diagram in the first embodiment of the multi-chamber air conditioning system of the present invention is the same as that of the conventional example, and therefore the description is omitted. In this embodiment, a case where three indoor units 21a, 21b, and 21c are connected to one outdoor unit 20 will be described.

FIG. 1 is a block diagram showing the flow of control of the compressor frequency and the electric expansion valve opening, and FIG. 2 is a temperature zone division diagram of the temperature difference ΔT between the room temperature Tr and the set temperature Ts.

First, in the indoor unit 21a, the output of the indoor temperature sensor 36a is sent from the indoor temperature detecting circuit 1 to the temperature difference calculating circuit 2 as a temperature signal, and the setting determining circuit 3 sets the output in the operation setting circuit 37a. The set temperature and the operation mode are determined and sent to the differential temperature calculation circuit 2. here,
The temperature difference ΔT (= Tr−Ts) is calculated, converted into the load number Ln value shown in FIG. 2, and used as a temperature difference signal. For example, assuming that Tr = 29.3 ° C. and Ts = 26 ° C. during the cooling operation, the temperature difference ΔT = 3.3 ° C. and the air-conditioning load maximum zone Ln =
It becomes 8. The ON-OFF determination circuit 4 determines whether the indoor unit 21a is operated (ON) or stopped (OFF) set by the operation setting circuit 37a, and further stores the rated capacity of the indoor unit 21a in the rated capacity storage circuit 5. In addition, these rated capacity signal, differential temperature signal, operation mode signal, ON-OF
The F determination signal is sent from the signal sending circuit 6 to the signal receiving circuit 7 of the outdoor unit 20. Similar signals are sent to the signal receiving circuit 7 from the indoor units 21b and 21c. The signal received by the signal receiving circuit 7 is sent to a compressor frequency calculating circuit 8 and an expansion valve opening calculating circuit 9. However, if there is a different operation mode signal, the operation mode of the indoor unit that started operation first has priority, and the ON-OFF determination signal is always OFF, assuming that the indoor unit in the different operation mode is stopped. Is sent.

The compressor unit 8 operates the indoor unit 21.
The load constants are read from the load constant table 10 shown in Table 3 below from the respective rated capacity signals a, 21b, and 21c, the differential temperature signal, the operation mode signal, and the ON-OFF determination signal, and the sum of the load constants is multiplied by the constant. Thus, the frequency of the compressor 22 is determined.

[0042]

[Table 3]

As an example, a case where signals from the indoor units 21a, 21b, and 21c at the time of starting operation during cooling will be described in Table 4 below.

[0044]

[Table 4]

From Tables 3 and 4, the indoor units 21a, 21b,
The load constants of 21c are 2.4, 3.0, and 0, respectively. Therefore, when A is a constant, the frequency Hz of the compressor 22 is as follows: Hz = A × (2.4 + 3.0 + 0) = A × 5.4 . The allowable operation value of the compressor 22 is the indoor units 21a, 21
b, 21c, 2.0, 2.5, 3.
2, the frequency calculation result does not reach the allowable operation value of the compressor 22, leaving a margin of about 30%, and this calculation result is used as a frequency signal to drive the compressor. The signal is sent to a circuit (not shown) to control the frequency of the compressor 22. Thereafter, the indoor units 21a, 21b, 2
The calculation is performed from the rated capacity signal, the differential temperature signal, the operation mode signal, and the ON / OFF determination signal of each of the indoor units 2c.
The frequency is continued until Ln = 7 for all the units, and the calculation result is sent to a compressor drive circuit (not shown) as a frequency signal to control the frequency of the compressor 22.

Next, as shown in Table 5, the indoor units 21a, 21b
The case where the operation of the indoor unit 21c is started during the operation at low load will be described.

[0047]

[Table 5]

From Tables 3 and 5, the indoor units 21a, 21b,
The load constants of 21c are 0.8, 1.0, and 3.8, respectively, so the frequency Hz of the compressor 22 is similarly given by: Hz = A × (0.8 + 1.0 + 3.8) = A × 5.6 The frequency calculation result does not reach the allowable operation value of the compressor 22 and has a margin of about 30%. The calculation result is sent to a compressor drive circuit (not shown) as a frequency signal. , The frequency of the compressor 22 is controlled. Thereafter, the rated capacity signal, the differential temperature signal, the operation mode signal, and the ON-OFF of each of the indoor units 21a, 21b, and 21c at predetermined intervals.
The calculation is performed based on the determination signal. If the loads on the indoor units 21a and 21b are the same, the above frequency is continued until the indoor unit 21c reaches Ln = 7, and the calculation result is used as a frequency signal as a compressor drive circuit (not shown). ) To control the frequency of the compressor 22. The load of the indoor units 21a and 21b is Ln =
In the case of 7, the frequency becomes Hz = A × (2.0 + 2.5 + 3.8) = A × 8.3, which exceeds the allowable operating value of the compressor 22. As a permissible operation value of the compressor 22, it is sent to the compressor drive circuit to control the frequency of the compressor 22.

Similarly, in the expansion valve opening calculation circuit 9,
A load constant is selected from the load constant table 10 shown in Table 3 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 21a, 21b, and 21c. Is read from the valve initial opening table 11 for each rated capacity shown in Table 6 below. Note that the valve initial opening is determined so that each indoor unit can perform a predetermined capacity control even with a combination of indoor units having different rated capacities.

[0050]

[Table 6]

The valve opening of the electric expansion valves 30a, 30b, 30c is obtained by dividing each load constant by a predetermined value of the load constant and multiplying the result by the initial valve opening. As in the case of the compressor frequency calculation example, first, the indoor units 21a, 21b, 2
The case where the signal from 1c is shown in Table 4 will be described.

The (load constant / predetermined load constant) of each of the indoor units 21a, 21b and 21c is (2.4 / 2.0),
(3.0 / 2.5) and (0 / 3.2), and the initial valve openings are 100, 130 and 180, respectively. Therefore, the valve openings of the electric expansion valves 30a, 30b, 30c are 120, 187, 0 (rounded to one decimal place). This calculation result is sent to an expansion valve drive circuit (not shown) as an expansion valve opening signal. Thereafter, at predetermined intervals, the valve openings of the electric expansion valves 30a, 30b, and 30c are calculated from the temperature difference signal, the operation mode signal, and the ON-OFF determination signal, and the results of these calculations are used as expansion valve opening signals as expansion valve signals. It is sent to a drive circuit (not shown).

Next, the case of Table 5 will be described. Table 4
As in the case of (1), (load constant / predetermined load constant) of each of the indoor units 21a, 21b, and 21c is (0.8 / 2.
0), (1.0 / 2.5) and (3.8 / 3.2), and the initial valve opening is 100, 130, and 180, respectively.
It is. Therefore, the electric expansion valves 30a, 30b, 30
The valve opening degree of c is 40, 52, 214 (rounded to one decimal place). This calculation result is sent to an expansion valve drive circuit (not shown) as an expansion valve opening signal. Thereafter, at predetermined intervals, the differential temperature signal, the operation mode signal, the ON-OFF
The valve openings of the electric expansion valves 30a, 30b, 30c are calculated from the discrimination signal, and the results of these calculations are sent to an expansion valve drive circuit (not shown) as expansion valve opening signals.

Although the above description has been made mainly for cooling, the same can be applied to heating.

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 is controlled so as to supply a sufficient outdoor capacity, the time required to reach the set temperature can be shortened, so that comfort can be improved and energy can be saved.

Next, a second embodiment of the present invention will be described with reference to the drawings. The refrigeration cycle in the second embodiment is the same as the conventional example, as in the first embodiment. FIG. 3 is a block diagram showing a flow of control of the compressor frequency in the second embodiment of the present invention. This figure is different from the first embodiment in that when calculating the compressor capacity for each predetermined cycle, there is a differential temperature signal corresponding to the maximum air conditioning load zone even in one room, and the compressor capacity becomes the allowable operating value. Is less than the above, a load constant calculating means for calculating a load constant value of the indoor unit in the maximum air conditioning load zone by an approximate expression is provided in the compressor frequency calculation circuit.

First, in the indoor unit 21a, the output of the indoor temperature sensor 36a is sent from the indoor temperature detecting circuit 1 to the temperature difference calculating circuit 2 as a temperature signal, and is set by the setting setting circuit 3 in the operation setting circuit 37a. The set temperature and the operation mode are determined and sent to the differential temperature calculation circuit 2. here,
The temperature difference ΔT (= Tr−Ts) is calculated, converted into the load number Ln value shown in FIG. 2, and used as a temperature difference signal. Also O
The N-OFF determination circuit 4 operates (ON) or stops (OF) the indoor unit 21a set by the operation setting circuit 37a.
F), and further stores the indoor unit 21 in the rated capacity storage circuit 5.
a is stored, and these rated capacity signals,
The temperature difference signal, the operation mode signal, and the ON-OFF determination signal are sent from the signal sending circuit 6 to the signal receiving circuit 7 of the outdoor unit 20.
Similar signals are sent to the signal receiving circuit 7 from the indoor units 21b and 21c. The signal received by the signal receiving circuit 7 is sent to a compressor frequency calculating circuit 8.

In the compressor frequency calculation circuit 8, the indoor unit 21
The load constants are read from the load constant table 10 shown in Table 7 below from the rated capacity signals, the differential temperature signals, the operation mode signals, and the ON / OFF discrimination signals of the respective a, 21b, and 21c. Multiplying compressor 22
Is calculated. If even one of the indoor units 21a, 21b, 21c has a load in the maximum air conditioning load zone (Ln = 8) and the calculated frequency is less than the allowable operation value of the compressor 22, the maximum air conditioning load zone (Ln = 8) Is calculated by an approximate expression, and the sum of the load constants is again multiplied by the constant to calculate the frequency of the compressor 22.

[0059]

[Table 7]

The case of Table 4 will be described similarly to the above embodiment. Since the loads of the indoor units 21a and 21b are both in the air-conditioning load maximum zone at Ln = 8, the load constants of the indoor units 21a, 21b, and 21c from the load constant cable 10 shown in Table 7 are 2.0, 2.5 , 0. If A is a constant, the frequency Hz of the compressor 22 is as follows: Hz = A × (2.0 + 2.5 + 0) = A × 4.5, and the allowable operation value of the compressor 22 (Hz = A × 7.7)
Less than. Therefore, the load constants of the indoor units 21a and 21b in the air-conditioning load maximum zone are calculated by an approximate expression.
This approximate expression is expressed as a function of, for example, the rated capacity of each indoor unit and the load constant of each indoor unit. Calculated load constant and Ln
The frequency of the compressor 22 is calculated by multiplying the sum of the load constants obtained from the load constant table 10 shown in Table 7 by a constant in an indoor unit of = 7 or less. This is sent as a frequency signal to a compressor drive circuit (not shown) to control the frequency of the compressor 22.

As described above, since the load constants of the indoor units in the air-conditioning load maximum zone are obtained by an approximate expression using, for example, the rated capacity of each indoor unit and the load constant of each indoor unit as functions, more detailed load handling can be achieved. It is possible, and the time required to reach the set temperature can be shortened, so that comfort can be improved and energy can be saved.

In the above embodiment, the difference temperature signal of the air-conditioning load maximum zone is only Ln = 8. However, the temperature difference of the air-conditioning load maximum zone is finely divided, and the difference temperature signal is converted into a numerical value in eight or more steps. If an approximate expression is set as a function of the rated capacity of each indoor unit, the load constant of each indoor unit, and the differential temperature signal of the target indoor unit as a function, it is possible to cope with a more detailed load.

Next, a third embodiment of the present invention will be described with reference to the drawings. Note that the refrigeration cycle in the third embodiment is the same as the conventional example, as in the first embodiment, and thus the description thereof is omitted. Further, a block diagram showing a flow of control of the compressor frequency in the third embodiment of the present invention is the same as the block diagram of the second embodiment (FIG. 3), and thus its description is omitted. This embodiment is different from the above-described second embodiment in that when calculating the compressor capacity for each predetermined cycle, even in one room, there is a differential temperature signal corresponding to the air conditioning load maximum zone,
When the compressor capacity is less than the allowable operation value, the load constant of the indoor unit in the load maximum zone is calculated from the compressor capacity margin, and the frequency control of the compressor is performed.

First, in the indoor unit 21a, the output of the indoor temperature sensor 36a is sent from the indoor temperature detecting circuit 1 to the temperature difference calculating circuit 2 as a temperature signal, and the setting determining circuit 3 sets the output in the operation setting circuit 37a. The set temperature and the operation mode are determined and sent to the differential temperature calculation circuit 2. here,
The temperature difference ΔT (= Tr−Ts) is calculated, converted into the load number Ln value shown in FIG. 2, and used as a temperature difference signal. Also O
The N-OFF determination circuit 4 operates (ON) or stops (OF) the indoor unit 21a set by the operation setting circuit 37a.
F), and further stores the indoor unit 21 in the rated capacity storage circuit 5.
a is stored, and these rated capacity signals,
The temperature difference signal, the operation mode signal, and the ON-OFF determination signal are sent from the signal sending circuit 6 to the signal receiving circuit 7 of the outdoor unit 20.
Similar signals are sent to the signal receiving circuit 7 from the indoor units 21b and 21c. The signal received by the signal receiving circuit 7 is sent to a compressor frequency calculating circuit 8.

In the compressor frequency calculation circuit 8, the indoor unit 21
The load constants are read from the load constant table 10 shown in Table 7 from the rated capacity signals, the differential temperature signals, the operation mode signals, and the ON / OFF discrimination signals of the respective a, 21b, and 21c. Multiplying compressor 22
Is calculated. If even one of the indoor units 21a, 21b, 21c has a load in the maximum air conditioning load zone (Ln = 8) and the calculated frequency is less than the allowable operation value of the compressor 22, the maximum air conditioning load zone (Ln = 8) Is calculated by multiplying the sum of the load constants of the respective rooms by the sum of the rated capacities of the respective rooms by a compressor capacity margin, and multiplying the sum of the load constants again by a constant to calculate the frequency of the compressor 22. Is calculated.

The case of Table 5 in the first embodiment of the present invention will be described. Since the loads of the indoor units 21a and 21b are both Ln = 4 and the load of the indoor unit 21c is Ln = 8 and is in the air-conditioning load maximum zone, first, the load constant table 10 shown in Table 7 shows the load of the indoor units 21a, 21b and 21c. The load constants are 0.8, 1.0, and 3.2. Assuming that A is a constant, the frequency Hz of the compressor 22 is as follows: Hz = A × (0.8 + 1.0 + 3.2) = A × 5.0, and the allowable operating value of the compressor 22 (Hz = A × 7.7) )
Less than. At this time, the compressor capacity margin is 1-5.0.
/7.7=0.35, the load constant of the indoor unit 21c is 3.2 × (1 + 0.35) = 4.3, and the compressor 22
Is Hz = A × (0.8 + 1.0 + 4.3) = A × 6.1. This is sent as a frequency signal to a compressor drive circuit (not shown) to control the frequency of the compressor 22.

As described above, since the load constant of the indoor unit in the maximum air-conditioning load zone is added by multiplying the compressor capacity margin, the margin capacity can be effectively used in consideration of the margin of the compression function power. A finer load response can be achieved, the time required to reach the set temperature can be shortened, and comfort can be improved and energy can be saved.

Next, a fourth embodiment of the present invention will be described with reference to the drawings. 4 is a refrigeration cycle in the fourth embodiment, FIG. 5 is a block diagram showing a flow of a compressor frequency in the fourth embodiment of the present invention, and FIG. 6 is a relationship between the number of operating indoor units and a target value of condensing pressure control. FIG. FIG. 4 is different from the first to third embodiments in that the pressure sensor 4 for measuring the condensation pressure at the outlet of the compressor 22 in the outdoor unit 20.
5 is different from the first embodiment and the second embodiment in that the output of the pressure sensor 40 for measuring the condensing pressure is output from the condensing pressure detecting circuit 12 as a condensing pressure data signal to the compressor. When the compressor capacity is less than the operation allowable value when there is a temperature difference signal corresponding to the air-conditioning load maximum zone even in one of the rooms when the compressor capacity is calculated for each predetermined cycle and sent to the frequency calculation circuit 8, The compressor 22 is controlled to approach the control target value of the refrigeration cycle data according to the number of operating indoor units.
Is provided with a compressor frequency calculation circuit 8 for increasing and decreasing the frequency of the compressor.

First, in the indoor unit 21a, the output of the indoor temperature sensor 36a is sent from the indoor temperature detecting circuit 1 to the differential temperature calculating circuit 2 as a temperature signal, and is set by the operation setting circuit 37a by the setting determining circuit 3. The set temperature and the operation mode are determined and sent to the differential temperature calculation circuit 2. here,
The temperature difference ΔT (= Tr−Ts) is calculated, converted into the load number Ln value shown in FIG. 2, and used as a temperature difference signal. Also O
The N-OFF determination circuit 4 operates (ON) or stops (OF) the indoor unit 21a set by the operation setting circuit 37a.
F), and further stores the indoor unit 21 in the rated capacity storage circuit 5.
a is stored, and these rated capacity signals,
The temperature difference signal, the operation mode signal, and the ON-OFF determination signal are sent from the signal sending circuit 6 to the signal receiving circuit 7 of the outdoor unit 20.
Similar signals are sent to the signal receiving circuit 7 from the indoor units 21b and 21c. The signal received by the signal receiving circuit 7 is sent to a compressor frequency calculating circuit 8.

In the outdoor unit 20, for example, the condensing pressure is measured by the pressure sensor as the refrigeration cycle data, and the output is sent to the condensing pressure detecting circuit 12. Further, the compressor frequency calculating circuit 8 outputs the condensing pressure detecting circuit 12 as a pressure signal.
To send to.

In the compressor frequency calculation circuit 8, the indoor unit 21
The load constants are read from the load constant table 10 shown in Table 7 from the rated capacity signals, the differential temperature signals, the operation mode signals, and the ON / OFF discrimination signals of the respective a, 21b, and 21c. Multiplying compressor 22
Is calculated. When the load of one of the indoor units 21a, 21b, and 21c is in the air-conditioning load maximum zone (Ln = 8) and the calculated frequency is less than the allowable operation value of the compressor 22, the indoor unit 21 The control target value of the condensing pressure is determined from the number of operating units, and the frequency of the compressor 22 is increased by the compressor frequency calculation circuit 8 so as to approach the control target value of the condensing pressure. (Not shown) to control the frequency of the compressor 22.

The case of Table 5 in the first embodiment of the present invention will be described. Since the loads of the indoor units 21a and 21b are both Ln = 4 and the load of the indoor unit 21c is Ln = 8 and is in the air-conditioning load maximum zone, first, the load constant table 10 shown in Table 7 shows the load of the indoor units 21a, 21b and 21c. The load constants are 0.8, 1.0, and 3.2. Assuming that A is a constant, the frequency Hz of the compressor 22 is as follows: Hz = A × (0.8 + 1.0 + 3.2) = A × 5.0, and the operation allowable condensing pressure of the compressor 22 (Hz = A ×
Less than 7.7). Therefore, according to FIG.
The control target value B of the condensing pressure in the case of the unit is determined, and the frequency of the compressor 22 is increased by the compressor frequency calculating circuit 8 so that the pressure signal from the condensing pressure detecting circuit 12 approaches B. To a compressor drive circuit (not shown) to control the frequency of the compressor 22.

As described above, when the indoor unit is located in the maximum air-conditioning load zone, refrigeration cycle data such as condensing pressure is set as a control target value according to the number of operating indoor units.
Because the frequency of the compressor 22 is controlled, it is possible to respond to a fine load without overloading the compressor,
The time to reach the set temperature can be shortened,
It is possible to improve comfort and save energy.
Also, if a multi-room air conditioning system with four or more indoor units is used, the number of operating units will increase, and the determination of the value will be controlled using refrigeration cycle data as a target, rather than controlling with complex load constants. Doing so has an advantage that stability as a refrigeration cycle can be ensured.

In the above embodiment, the case where the refrigeration cycle data is used as the condensing pressure has been described. However, the same effect can be obtained by using the physical quantities such as the evaporating pressure, the condensing temperature, the discharge temperature and the operating current of the compressor.

Next, a fifth embodiment of the present invention will be described with reference to the drawings. Note that the refrigeration cycle in the fifth embodiment is the same as the conventional example, as in the first embodiment, and a description thereof will be omitted. FIG. 7 is a block diagram showing the flow of control of the compressor frequency in the fifth embodiment of the present invention. This figure differs from the first to fourth embodiments in that the load constant table 10 for each rated capacity is not used. That is, the load constant of each indoor unit is calculated by the compressor frequency calculation circuit 8 by an approximate expression from the number of operating indoor units, the respective rated capacities, and the respective room temperature difference signals.

First, in the indoor unit 21a, the output of the indoor temperature sensor 36a is sent from the indoor temperature detecting circuit 1 to the temperature difference calculating circuit 2 as a temperature signal, and the setting determining circuit 3 sets the output in the operation setting circuit 37a. The set temperature and the operation mode are determined and sent to the differential temperature calculation circuit 2. here,
The temperature difference ΔT (= Tr−Ts) is calculated, converted into the load number Ln value shown in FIG. 2, and used as a temperature difference signal. Also O
The N-OFF determination circuit 4 operates (ON) or stops (OF) the indoor unit 21a set by the operation setting circuit 37a.
F), and further stores the indoor unit 21 in the rated capacity storage circuit 5.
a is stored, and these rated capacity signals,
The temperature difference signal, the operation mode signal, and the ON-OFF determination signal are sent from the signal sending circuit 6 to the signal receiving circuit 7 of the outdoor unit 20.
Similar signals are sent to the signal receiving circuit 7 from the indoor units 21b and 21c. The signal received by the signal receiving circuit 7 is sent to a compressor frequency calculating circuit 8.

The indoor unit 21 is operated by the compressor frequency calculating circuit 8.
a, 21b, and 21c, a load constant is calculated by an approximate expression from the rated capacity signal, the differential temperature signal, the operation mode signal, and the ON-OFF determination signal, and the sum of the load constants is multiplied by a constant to calculate the load constant of the compressor 22. Calculate the frequency.

As described above, since the load constant of each indoor unit is calculated from the number of operating indoor units, the respective rated capacities, and the respective room temperature difference signals by an approximate expression, a more detailed load response is possible. The time required to reach the set temperature can be shortened, and comfort can be improved and energy can be saved. Further, since a load constant table is not required, it is not necessary to increase the capacity of the storage circuit even if the number of indoor units increases. The indoor units 21a, 21b, 2
Air conditioning load maximum zone (Ln = 8) even if the load of 1c is one room
, The load constant of the indoor unit in the air-conditioning load maximum zone (Ln = 8) can also be calculated by an approximate expression, and the frequency of the compressor 22 can be calculated by multiplying the sum of the load constants by a constant. At this time, if the temperature increment in the air-conditioning load maximum zone is finely set and the differential temperature signal is set to a numerical value in eight or more stages, a more detailed load response is possible.

Next, a sixth embodiment of the present invention will be described with reference to the drawings. Note that the refrigeration cycle in the sixth embodiment is the same as the conventional example, similarly to the first embodiment, and therefore the description is omitted. FIG. 8 is a block diagram showing a control flow of the compressor frequency and the electric expansion valve opening in the sixth embodiment of the present invention.

A method of controlling the degree of opening of the electric expansion valve in this embodiment will be described. In FIG. 8, the indoor units 21a, 2a
In the case where at least one of the compressors 1b and 21c is in the maximum air-conditioning load zone in the temperature zone division diagram of FIG. 2, and the compressor capacity calculated by the compressor frequency calculation circuit 8 is less than the operation allowable value of the compressor 22 When calculating the compressor capacity in each predetermined cycle, the load constant of the indoor unit in the maximum air-conditioning load zone is calculated based on the data obtained from the differential temperature detection circuit 2, the ON-OFF determination circuit 4, and the rated capacity storage circuit 5. The process up to calculating the frequency of the compressor 22 and multiplying the sum with the load constants of the other indoor units by a constant to determine the frequency of the compressor 22 is the same as in the second to fourth embodiments. The calculation result is sent to a compressor drive circuit (not shown) as a frequency signal to control the frequency of the compressor 22 and to the expansion valve opening calculation circuit 9.
In the expansion valve opening calculation circuit 9, first, the indoor unit 2
The valve initial opening is read from the valve initial opening table 11 based on the rated capacity of each of the valves 1a, 21b, and 21c. Further, the valve opening of the electric expansion valves 30a, 30b, 30c is determined by multiplying the previously calculated load constant of the indoor units 21a, 21b, 21c by a predetermined value of the load constant and multiplying the result by the initial valve opening. I do.

As described above, even if the load of the indoor unit is in the maximum air-conditioning load zone, if there is a margin in the capacity of the compressor 22, the extra room is utilized for the indoor unit in the maximum air-conditioning load zone. In order to control the compressor frequency to supply the minute capacity, and to control the opening of the electric expansion valve in accordance with the capacity, the distribution of the capacity of the refrigeration cycle is controlled optimally until the set temperature is reached. Can be shortened, and comfort can be improved and energy can be saved.

[0082]

As is apparent from the above embodiment, the multi-room air conditioning system of the present invention has an indoor temperature setting means capable of setting a desired indoor temperature for each of the indoor units and an indoor room for detecting the indoor temperature. Temperature detecting means, and 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 determining a rated capacity of each of the indoor units. Capacity determining means and on / off determining means for determining whether the indoor unit is operating or stopped for each of the indoor units, divides a temperature range in which the temperature difference can be taken into a plurality of temperature zones, and for each temperature zone and A load constant corresponding to the indoor load is determined for each rated capacity of the indoor unit, and a maximum air-conditioning load zone that is equal to or higher than a predetermined temperature zone for cooling and equal to or lower than a predetermined temperature zone for heating is provided. A load constant storage means for determining and storing a load constant equal to or greater than a rated capacity for each capacity; a valve initial opening storage means for determining and storing a valve initial opening for each rated capacity of the indoor unit; Means for calculating the compressor capacity at predetermined intervals using data obtained from the means, the capacity determination means, the on / off determination means, and the load constant storage means, there is a load constant corresponding to an air conditioning load maximum zone even in one room. If the compressor capacity is less than the allowable operating value,
Compressor capacity control means for controlling the capacity of the variable capacity (frequency) compressor based on the capacity value calculated using the load constant of the air conditioning load maximum zone obtained from the load constant storage means is provided. Calculating the valve opening of each electric expansion valve connected to the operating indoor unit at predetermined intervals using the data and the data obtained from the valve initial opening storage means, and based on the calculation result, By providing the valve opening control means for controlling the valve opening of the electric expansion valve, the capacity corresponding to the load is supplied to the indoor unit with a small load, and only the indoor unit with the maximum load has a margin. Since the compressor frequency is controlled so as to supply the outdoor capacity, the time required to reach the set temperature can be shortened, so that comfort can be improved and energy can be saved.

Each of the indoor units is provided with an indoor temperature setting means capable of setting a desired indoor temperature and an indoor temperature detecting means detecting the indoor temperature. A differential temperature calculating means for calculating a temperature difference between the indoor temperature and the indoor temperature; a capacity determining means for determining a rated capacity of each of the indoor units; and determining whether each of the indoor units is operating or stopped. On / off determining means is provided, the temperature range in which the temperature difference can be taken is divided into a plurality of temperature zones, and a load constant corresponding to an indoor load is determined for each temperature zone and for each rated capacity of the indoor unit. Provide a maximum air-conditioning load zone equal to or higher than a predetermined temperature zone and a predetermined temperature zone or less for heating, and determine a differential temperature signal indicating that the air conditioner is in the maximum air-conditioning load zone for each rated capacity of the indoor unit. A load constant storing means for storing the temperature difference, 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 maximum air conditioning load zone in the room, and the compressor capacity is less than the allowable operation value, the load constant for calculating the load constant value of the indoor unit in the maximum air conditioning load zone using an approximate expression Calculating means for calculating a compressor capacity using the data and the load constant data obtained by the load constant calculating means, and controlling a capacity of the variable capacity (frequency) compressor based on the calculation result. By providing the compressor capacity control means, the load constant value of the indoor unit in the maximum air conditioning load zone is obtained by an approximate expression using the rated capacity of the indoor unit and the differential temperature data, and the compressor frequency is obtained. Gosuru Therefore, it is possible fine load correspondence, it is possible to quickly the time to reach the set temperature, it is possible to improve and energy saving comfort.

Further, each of the indoor units is provided with an indoor temperature setting means for setting a desired indoor temperature and an indoor temperature detecting means for detecting the indoor temperature, and the indoor temperature setting means and the indoor temperature detecting means are used for setting. A differential temperature calculating means for calculating a temperature difference between the indoor temperature and the indoor temperature; a capacity determining means for determining a rated capacity of each of the indoor units; and determining whether each of the indoor units is operating or stopped. On / off determining means is provided, the temperature range in which the temperature difference can be taken is divided into a plurality of temperature zones, and a load constant corresponding to an indoor load is determined for each temperature zone and for each rated capacity of the indoor unit. Provide a maximum air-conditioning load zone equal to or higher than a predetermined temperature zone and a predetermined temperature zone or less for heating, and determine a differential temperature signal indicating that the air conditioner is in the maximum air-conditioning load zone for each rated capacity of the indoor unit. A load constant storing means for storing the temperature difference, 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 the room, and the compressor capacity is less than the allowable operating value, the load constant for calculating the load constant value of the indoor unit in the air conditioning load maximum zone from the compressor margin Calculating means for calculating a compressor capacity using the data and the load constant data obtained by the load constant calculating means, and controlling a capacity of the variable capacity (frequency) compressor based on the calculation result. By providing the compressor capacity control means, the load constant of the indoor unit in the air-conditioning load maximum zone is added by multiplying the compressor capacity margin, so that the margin of the compression function power is considered. Margin capacity can be effectively utilized, it is possible more granular load correspondence, it is possible to quickly the time to reach the set temperature, it is possible to improve and energy saving comfort.

Further, each of the indoor units is provided with an indoor temperature setting means for setting a desired indoor temperature and an indoor temperature detecting means for detecting the indoor temperature, and the indoor temperature setting means and the indoor temperature detecting means are used for setting. A differential temperature calculating means for calculating a temperature difference between the indoor temperature and the indoor temperature; a capacity determining means for determining a rated capacity of each of the indoor units; and determining whether each of the indoor units is operating or stopped. On / off determining means is provided, the temperature range in which the temperature difference can be taken is divided into a plurality of temperature zones, and a load constant corresponding to an indoor load is determined for each temperature zone and for each rated capacity of the indoor unit. Provide a maximum air-conditioning load zone equal to or higher than a predetermined temperature zone and a predetermined temperature zone or less for heating, and determine a differential temperature signal indicating that the air conditioner is in the maximum air-conditioning load zone for each rated capacity of the indoor unit. Providing a load constant storage means for storing, and a refrigeration cycle data detection means for detecting a state of the refrigeration cycle, and storing data obtained from the differential temperature calculation means, the capacity determination means, the on / off determination means, and the load constant storage means. When the compressor capacity is calculated for each predetermined cycle using the temperature difference signal corresponding to the maximum air-conditioning load zone even in one room, if the compressor capacity is less than the operation allowable value, the number of indoor units operated is reduced. Accordingly, the compressor capacity is calculated so as to approach the control target value of the refrigeration cycle data, and compressor capacity control means for controlling the capacity of the capacity (frequency) variable compressor based on the calculation result is provided. If there is an indoor unit in the maximum air conditioning load zone, the frequency of the compressor is set according to the number of operating indoor units, using refrigeration cycle data such as condensation pressure as the control target value. Gosuru Therefore, without the compressor overload, it is possible fine load correspondence, it is possible to quickly the time to reach the set temperature, it is possible to improve and energy saving comfort.

Further, each of the indoor units is provided with an indoor temperature setting means for setting a desired indoor temperature and an indoor temperature detecting means for detecting the indoor temperature, and the indoor temperature setting means and the indoor temperature detecting means are used for setting. A differential temperature calculating means for calculating a temperature difference between the indoor temperature and the indoor temperature; a capacity determining means for determining a rated capacity of each of the indoor units; and determining whether each of the indoor units is operating or stopped. Load constant calculating means for providing an on / off determining means, dividing a temperature range in which the temperature difference can be taken into a plurality of temperature zones, and calculating a load constant of each indoor unit by an approximate expression using the data at predetermined intervals. Is provided, and compressor capacity control means for controlling the capacity of the variable capacity (frequency) compressor based on the calculation result is provided, so that the load constant of each indoor unit is reduced. Calculated by an approximate formula from the number of operating internal units, their respective rated capacities, and each room temperature difference signal, it is possible to respond more finely to the load and shorten the time required to reach the set temperature. Therefore, it is possible to improve comfort and save energy. Further, since a load constant table is not required, it is not necessary to increase the capacity of the storage circuit even if the number of indoor units increases.

Further, for each of the indoor units during and after operation, the load constant corresponding to the rated capacity and the present differential temperature and a predetermined value of the load constant are read from the load constant storage means, and the valve initial opening degree storage means is read. Read the initial valve opening corresponding to the rated capacity and read the indoor unit in the maximum air-conditioning load zone when the compressor capacity is less than the allowable operating value if there is a load constant corresponding to the maximum air-conditioning load zone even in one room. The valve opening for controlling the valve opening of the electric expansion valve connected to the valve as a product of the reciprocal of a predetermined value of the load constant, the load constant calculated by the load constant calculating means and the valve initial opening, and the value of this product. By providing the control means, even if the load of the indoor unit is in the maximum air-conditioning load zone, if there is a margin in the capacity of the compressor 52 as described above, the room is in the maximum air-conditioning load zone by utilizing the margin. The compressor frequency is controlled to supply the extra capacity to the internal unit, and the opening of the electric expansion valve is controlled according to the capacity. The time until the temperature is reached can be shortened, and comfort can be improved and energy can be saved.

[Brief description of the drawings]

FIG. 1 is a control block diagram of a compressor frequency and an electric expansion valve opening in a first embodiment of a multi-room air conditioning system of the present invention.

FIG. 2 (a) is a temperature zone division diagram of a temperature difference ΔT during cooling in the embodiment. (B) is a temperature zone division diagram of a temperature difference ΔT during heating.

FIG. 3 is a control block diagram of a compressor frequency in a second embodiment of the multi-room air conditioning system of the present invention.

FIG. 4 is a refrigeration cycle diagram in a fourth embodiment of the multi-room air conditioning system of the present invention.

FIG. 5 is a control block diagram of a compressor frequency in a fourth embodiment of the multi-room air conditioning system of the present invention.

FIG. 6 is a diagram showing a relationship between the number of operating indoor units and a target value of condensing pressure control in a fourth embodiment of the multi-room air conditioning system of the present invention.

FIG. 7 is a control block diagram of a compressor frequency in a fifth embodiment of the multi-room air conditioning system of the present invention.

FIG. 8 is a control block diagram of a compressor frequency in a sixth embodiment of the multi-room air conditioning system of the present invention.

FIG. 9 is a refrigeration cycle diagram of a conventional multi-room air conditioning system.

FIG. 10 is a control block diagram of a compressor frequency and an electric expansion valve opening of a conventional multi-room air conditioning system.

FIG. 11A is a conventional temperature zone division diagram of the differential temperature ΔT during cooling. FIG. 11B is a conventional temperature zone division diagram of the differential temperature ΔT during heating.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Room temperature detection circuit 2 Difference temperature calculation circuit 3 Setting discrimination circuit 4 ON-OFF discrimination circuit 5 Rated capacity storage circuit 6 Signal transmission circuit 7 Signal reception circuit 8 Compressor frequency calculation circuit 9 Expansion valve opening calculation circuit 10 Load constant table Reference Signs List 11 valve initial opening calculation circuit 12 condensation pressure detection circuit 20 outdoor unit 21a indoor unit 21b indoor unit 21c indoor unit 22 variable frequency compressor 23 outdoor heat exchanger 24 four-way valve 25a indoor heat exchanger 25b indoor heat exchanger 25c indoor Heat exchanger 26 Liquid side main pipe 27a Liquid side branch pipe 27b Liquid side branch pipe 27c Liquid side branch pipe 28 Gas side main pipe 29a Gas side branch pipe 29b Gas side branch pipe 29c Gas side branch pipe 30a Electric expansion valve 30b Electric expansion valve 30c Electric expansion valve 31 Receiver 32 Auxiliary throttle 33 Suction pipe 34 Bypass pipe 35 Auxiliary throttle 36a Room temperature Sensor 36b indoor temperature sensor 36c indoor temperature sensor 37a operation setting circuit 37b operation setting circuit 37c operation setting circuit 40 pressure sensor

────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-5-322275 (JP, A) JP-A-6-123474 (JP, A) JP-A-6-257828 (JP, A) JP-A-4- 363532 (JP, A) JP-A-7-35390 (JP, A) JP-A-3-79946 (JP, A) JP-A-2-57875 (JP, A) JP-A-6-2557827 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) F24F 11/02 102

Claims (6)

(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 And a load constant corresponding to the indoor load for each temperature zone and for each rated capacity of the indoor unit. A maximum air conditioning load zone that is equal to or higher than a predetermined temperature zone and equal to or lower than a predetermined temperature zone for heating is provided, and a load constant storage unit that determines and stores a load constant equal to or higher than the rated capacity for each rated capacity of the indoor unit is provided. Valve initial opening storage means for determining and storing a valve initial opening for each capacity is provided, and a predetermined value is obtained by 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 calculating the compressor capacity for each cycle, if there is a differential temperature signal corresponding to the air conditioning load maximum zone even in one room, and when the compressor capacity is less than the allowable operation value, the load constant Compressor capacity control means for controlling the capacity of the variable capacity (frequency) compressor based on the capacity value calculated using the load constant of the maximum air conditioning load zone obtained from the storage means; And using the data obtained from the valve initial opening storage means to calculate the valve opening of each electric expansion valve connected to the operating indoor unit at predetermined intervals, and based on the calculation result, the electric expansion valve A multi-chamber air conditioning system provided with a valve opening control means for controlling the valve opening. 2. 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 And a load constant corresponding to the indoor load for each temperature zone and for each rated capacity of the indoor unit. A maximum air conditioning load zone equal to or higher than a predetermined temperature zone and equal to or lower than a predetermined temperature zone in heating is provided. When calculating the compressor capacity at predetermined intervals using data obtained from the differential temperature calculation means, the capacity determination means, the on / off determination means, and the load constant storage means, even one room corresponds to the air-conditioning load maximum zone. If the compressor capacity is less than the permissible operating value when there is a differential temperature signal, the load constant calculation method for calculating the load constant of the indoor unit in the maximum air-conditioning load zone by an approximate expression A compressor that calculates a compressor capacity using the data and the load constant data obtained by the load constant calculation means, and controls the capacity of the variable capacity (frequency) compressor based on the calculation result. A multi-room air conditioning system provided with capacity control means. 3. A variable displacement (frequency) 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 And a load constant corresponding to the indoor load for each temperature zone and for each rated capacity of the indoor unit. Above a predetermined temperature zone, heating provides an air conditioning load maximum zone below the predetermined temperature zone, and a load constant storage means for determining and storing a differential temperature signal indicating that the air conditioner is in the air conditioning load maximum zone for each rated capacity of the indoor unit, The temperature difference calculating means, the capacity determining means,
When calculating the compressor capacity at predetermined intervals using the data obtained from the on / off determining means and the load constant storage means, if there is a differential temperature signal corresponding to the air conditioning load maximum zone even in one room, the compressor capacity Is smaller than the allowable operating value, a load constant calculating means for calculating a load constant value of the indoor unit in the air conditioning load maximum zone from the compressor margin is provided, and the data and the load constant data obtained by the load constant calculating means are provided. And a compressor capacity control means for controlling the capacity of the variable capacity (frequency) compressor based on the calculation result. 4. 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 And a load constant corresponding to the indoor load for each temperature zone and for each rated capacity of the indoor unit. Above a predetermined temperature zone, heating provides an air conditioning load maximum zone below the predetermined temperature zone, and a load constant storage means for determining and storing a differential temperature signal indicating that the air conditioner is in the air conditioning load maximum zone for each rated capacity of the indoor unit, Refrigeration cycle data detection means for detecting the state of the refrigeration cycle is provided, and the compressor capacity is determined at predetermined intervals using data obtained from the temperature difference calculation means, 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 of the rooms when the compressor capacity is less than the allowable operating value, Multi-chamber provided with compressor capacity control means for controlling the capacity of the variable capacity (frequency) compressor based on the calculation result. Type air conditioning system. 5. A variable displacement (frequency) 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 Load constant calculating means for dividing the temperature range in which the temperature difference can be taken into a plurality of temperature zones, and calculating the load constant of each indoor unit by an approximate expression using the data at predetermined intervals. And calculate the compressor capacity, and based on the calculation result, the capacity (frequency)
A multi-room air conditioning system provided with compressor capacity control means for controlling the capacity of a variable compressor. 6. A load initial value storage means for reading a rated capacity and a load constant corresponding to a current differential temperature from a load constant storage means for each of the indoor units during and after operation, and a valve initial opening degree storage means. Read the initial valve opening corresponding to the rated capacity and read the indoor unit in the maximum air-conditioning load zone when the compressor capacity is less than the allowable operating value if there is a load constant corresponding to the maximum air-conditioning load zone even in one room. The valve opening for controlling the valve opening of the electric expansion valve connected to the valve as a product of the reciprocal of a predetermined value of the load constant, the load constant calculated by the load constant calculating means and the valve initial opening, and the value of this product. The multi-room air conditioning system according to any one of claims 2 to 4, further comprising control means.