JPH03217746A - Multiroom type air-conditioner - Google Patents

Abstract

PURPOSE:To obtain a multiroom type air-conditioner having excellent comfortableness by operating a compressor in response to the detected temperature of the atmosphere and the total sum of requested capacities of indoor units, and driving flow control valves in response to the ratio of the capacitors of the units. CONSTITUTION:Differences between set temperatures 31A-31C of indoor units 2A-2C and indoor temperature sensors 30A-30C and required capacities QA-QC calculated from load capacities stored in memories 34A-34C are transferred to an outdoor controller 28. The controller 28 calculates the rotating speed of a compressor from the total value QT (QA+QB+QC) of the capacities of the indoor units and data associated in the controller 28 from the detected temperatures, and drives the compressor through an inverter 24. The openings of flow control valves 12A-12C are controlled by flow control valve drivers 36A-36C to openings to become suitable refrigerant flow rates for the capacities of the respective units, and the openings of the valves 12A-12C become ratios of the capacities to the total value of the capacities.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a multi-room air conditioner in which a plurality of indoor units are connected to one outdoor unit.

[Conventional technology]

Generally, the capacity control method for a multi-room air conditioner in which multiple indoor units are connected to one outdoor unit is as follows:
As described in Japanese Patent Application Laid-open No. 63-61844, the compressor rotation speed,
And, the one that controls the flow rate control valve provided for each indoor unit, or the one that controls the required capacity calculated from the difference between the set temperature and the indoor temperature by the capacity of each unit, as described in Japanese Patent Application Laid-open No. 1-193563. A system has been disclosed in which the compressor rotational speed is controlled in accordance with the total sum of the corrected required capacities.

[Problem to be solved by the invention]

The above conventional technology controls the compressor rotation speed based on the difference between the set temperature and the indoor temperature and the unit capacity. This was not taken into consideration when used in combination, making it difficult to control the optimum capacity, resulting in problems such as insufficient capacity or excess capacity.

An object of the present invention is to provide a multi-room air conditioner with excellent comfort by controlling the capacity according to the load in each room.

[Means to solve the problem]

In order to achieve the above object, the multi-room air conditioner of the present invention includes means for detecting indoor temperature, means for inputting a set temperature, and means for detecting the heat load of the room in which the indoor unit is installed. A means for transmitting the required capacity determined from the difference between the indoor temperature and the set temperature and the heat load to the outdoor unit, a means for detecting the outside air temperature, and a means for transmitting the required capacity calculated from the difference between the indoor temperature and the set temperature and the heat load to the outdoor unit, and a means for detecting the sum of the detected outside air temperature and the required capacity of each indoor unit. A means for operating the compressor accordingly and a means for driving a flow rate control valve according to the ratio of required capacities of each indoor unit are provided.

[Operation] In order to achieve the object of the present invention, by providing a means for detecting the indoor load, the capacity can be controlled according to fluctuations in the indoor load, and optimal capacity distribution becomes possible.

〔Example〕

Hereinafter, the present invention will be explained by examples.

FIG. 1 is a control circuit diagram of a multi-chamber air conditioner according to an embodiment of the present invention, and FIG. 2 is a diagram showing a refrigeration cycle of the multi-chamber air conditioner according to the embodiment of FIG. .

In Fig. 2, reference numeral 1 denotes an outdoor unit, including a compressor 3 whose capacity can be controlled by changing the rotation speed, a four-way valve 4 that switches the flow direction of refrigerant between cooling and heating operations, an outdoor heat exchanger 5, and an indoor unit. Outdoor fan 6 blowing air to the outside heat exchanger 5
, an electric expansion valve 7, a liquid tank 8 for storing surplus refrigerant, and an accumulator 9. 2A, 2B, 2C are indoor units, and indoor heat exchangers 10A, IOB,
10C, indoor fans IIA, IIB, and 11C that blow air to the indoor heat exchangers 10A, IOB, and IOC, respectively;
Electric flow control valves 12A, 12B, 12C that can control the flow rate of refrigerant to the indoor heat exchanger 10A, IOB, IOC
It is connected to the outdoor unit 1 through a gas side connecting pipe 13 and a liquid side connecting pipe 14.

The control circuit configuration of this multi-room air conditioner will be explained with reference to FIG.

The outdoor unit 1 includes a compressor discharge refrigerant temperature sensor 20,
A compressor suction refrigerant temperature sensor 21, an outdoor heat exchanger temperature sensor 22, and an outside air temperature sensor 23 are provided. An outdoor fan drive device 26 that drives the fan 6 and an outdoor controller 28 that controls an expansion valve drive device 27 that drives the expansion valve 7 are provided.

The indoor units 2A, 2B, 2C have indoor temperature sensors 30A, 30B, 30C and an indoor set temperature 31, respectively.
Operator 32A, 32B, which selects A, 31B, 31C,
32C and computing units 33A, 33B that calculate the indoor load.
33C and storage units 34A and 34 that store the calculated load.
B, 34C are installed, and indoor fans IIA, I
Indoor fan drive device 35A, 3 that drives IB, 11C
Indoor controllers 37A, 37B, and 37C are installed to control flow rate control valve drive devices 36A, 36B, and 36C that drive flow rate control valves 12A, 12B, and 12G.

Outdoor controller 28 and indoor controllers 37A, 37. B, 37C
data can be transferred in both directions, and the operation mode,
The test output of each sensor, required capacity, driving capacity, etc. are transferred via signal lines that connect each device.

The operation of the multi-room air conditioner configured as above will be explained. First, a case will be described in which all indoor units are operated for cooling.

The operation switches (not shown) of all the actuators 32A, 32B, 32C are turned on and the set temperatures 31A, 31B, 3
When 1C is higher than the indoor temperature detected by the indoor temperature sensors 30A, 30B, and 30G, all indoor units are operated for cooling. At this time, the four-way valve 4 is set to the cooling operation side, and the outdoor fan 6, indoor fans IIA, IIB, IIC
is driven.

In addition, the difference between the set temperature 31A of the indoor unit 2A and the temperature detected by the indoor temperature sensor 30A and the storage unit 3 are measured at regular intervals.
Required capacity Q calculated from the load capacity stored in 4A
^ is transferred to the outdoor controller 28. Similarly, indoor unit 2
The required capacity Qa is transferred from the indoor unit 2G, and the required capacity Qc is transferred from the indoor unit 2G to the outdoor controller 28. The outdoor controller 28 calculates the total required capacity Qt(
The compressor rotation speed is calculated from the temperature detected by the outside air temperature sensor 23 and the data built into the outdoor controller 28, and the compressor rotation speed is calculated via the inverter circuit 24. to drive.

However, if the compressor rotation speed exceeds the allowable rotation speed of the compressor, the compressor is driven at the maximum allowable rotation speed, and the capacity Qmax of the outdoor unit at the maximum allowable rotation speed is calculated. The actual supply capacity is the value obtained by multiplying the required capacity of the indoor unit by the ratio of the capacity Q wa a x and the total required capacity Qr.For example, the supplied heat QAO of the indoor unit 2A is Q^
・Q-ax/QT. This actual amount of heat to be supplied is transmitted to the indoor units 2A, 2B, and 2C as the required capacity. Further, the expansion valve 7 is connected to the compressor discharge refrigerant temperature sensor 2.
If the discharge refrigerant temperature detected at 0 is lower than the set temperature Ta, the opening degree determined by the compressor rotation speed and the set temperature Ta
If the temperature is higher than that, the discharge a refrigerant temperature is controlled via the expansion valve drive device 27 so that it becomes Td.

On the other hand, the opening degrees of the flow rate control valves 12A, 12B, and 12C are controlled by the flow rate control valve driving device [26A, 26B, and 26C] so that the refrigerant flow rate is appropriate for the required capacity of each indoor unit. That is, since the refrigerant flow rate and the capacity are proportional, the opening degree of each flow control valve 12A, 12B, 12C becomes the ratio of each required capacity and the total value of the required capacity.

Here, the required indoor load will be explained using FIGS. 3 and 4. Figure 3 shows the change in indoor temperature over time;
The figure shows the relationship between the room temperature increase rate and the difference between a set temperature that is preset in the storage unit according to the capacity of the indoor unit and the indoor temperature.

The indoor heat balance is expressed by the following equation, assuming that the amount of heat supplied is QL, the room temperature rises Δt in a minute time Δt, the indoor heat capacity Qllll, the indoor heat loss Q is the sum of the indoor heat generated and the heat entering from the outside, where: , the value measured the nth time is expressed by the subscript n, and the value measured the n-1st time is expressed by the subscript n-1.
The indoor heat capacity Q1 and the indoor heat loss are expressed by the following equations.

ΔTn - ΔTn-z (3) Using the above formula, the heat load of each indoor unit is calculated by each computing unit 31A, 31B, 31C, and the result is stored in the storage unit 3.
4A, 34B, and 34C.

However, the amount of heat required at that time is used as the amount of heat to be supplied.

On the other hand, by using the values shown in FIG. 4, the room temperature increase rate 8T/Δt increases as the difference between the set temperature and the room temperature increases, and the supply capacity increases.

Therefore, storage unit 34A. From the heat capacity Qal stored in 34B and 34G, the indoor heat loss Q, and the indoor increase rate ΔT/t, the supplied heat amount can be calculated using equation (1), and this supplied heat amount is sent to the outdoor unit as the required capacity of each indoor unit. do.

However, for a certain period of time to immediately after startup, the refrigeration cycle is unstable and the amount of heat cannot be calculated. During this period, the heat capacity Qmg and indoor heat loss Qi stored during the previous operation are used.

The high-temperature, high-pressure gas refrigerant discharged from the compressor 3 driven by the required capacity of each indoor unit passes through the four-way valve 4, exchanges heat with the air blown by the outdoor fan 6 in the outdoor heat exchanger 5, and is condensed. do. This condensed liquid refrigerant is depressurized by the expansion valve 7 to become a gas-liquid two-phase refrigerant, and is sent to each indoor unit 2A, 2B, 2C through the liquid side connection pipe 14. The refrigerant sent to the indoor unit 2A is reduced in pressure by the flow rate control valve 12A according to the required capacity, and is sent to the indoor heat exchanger 10A where it exchanges heat with the air blown by the indoor fan IIA and evaporates.

Similarly, it joins with the refrigerant evaporated in the indoor units 2B and 2C, is sent to the four-way valve 4 through the gas side connecting pipe 13, and returns to the compressor 8 via the accumulator 9.

In addition, if a part of the cooling operation is no longer required, turn off the operation switch of the controller, for example, fully open the flow control valve 12B of the indoor unit 2B to supply refrigerant to the indoor heat exchanger 10B. Eliminate heat absorption from the outside by not supplying heat. At this time, the pressure inside the indoor heat exchanger 10B becomes the same as that of the gas side connecting pipe 13, so the pressure becomes low and the refrigerant becomes a gas refrigerant.

The surplus refrigerant at this time is stored in the liquid tank 8.

Next, heating operation will be explained. All controls 32
The operation switches of A, 32B, and 32C are turned on, and the set temperatures 31A, 31B, and 31C are set to the indoor temperature sensors 30A and 32C.
3. If it is lower than the indoor temperature detected by OB, 30C,
All indoor units are heated. At this time, the four-way valve 4 is set to the heating operation side, and the indoor fan 6 and indoor fans 11A, IIB, and IIG are driven. In addition, similar to the refrigerant operation, the request is calculated from the difference between the set temperatures 31A, 31B, 31C and the temperatures checked by the indoor temperature sensors 30A, 30B, 30C and the load capacity stored in the storage units 34A, 34B, 34C. Ability QA. Qfl, Qc are transferred to the outdoor controller 28, the outdoor controller 28 calculates the compressor rotation speed from the total required capacity and the temperature detected by the outside air temperature sensor 23, and the inverter circuit 24 drives the compressor 3. do.

Further, the flow rate control valves 12A, 12B, 12C are driven according to the required capacity of the indoor units 2A, 2B, 2C as in the case of cooling operation, and the expansion valve 7 is operated according to the discharge temperature detected by the compressor discharge refrigerant temperature sensor 20. When the temperature is lower than the set value T, the temperature difference detected by the compressor suction refrigerant temperature sensor 21 and the outdoor heat exchanger temperature sensor 22 is controlled to be constant.

If the discharge temperature is higher than the set value T, the discharge temperature is T4.
controlled so that

During the heating operation, contrary to the cooling operation, the high temperature and high pressure gas refrigerant discharged from the compressor 3 is sent to the indoor units 2A, 2B and 2C through the four-way valve 4 and the gas side connecting pipe 13. Indoor heat exchanger 10A, IOB in indoor units 2A, 2B, 2C
, IOC radiates heat and becomes a liquid refrigerant, which flows through the flow control valves 12A, .
The pressure is reduced at 12B and 12c, and the liquid is sent to the expansion valve 7 through the liquid side connecting pipe 14. The pressure is further reduced by the expansion valve 7, and the outdoor heat exchanger 5 absorbs heat from the outside air, becoming a gas refrigerant, and the four-way valve 4
, passes through the accumulator 9 and returns to the compressor 3.

Since each flow rate control valve 12A, 12B, 12C is driven according to the required load of each indoor unit 2A, 2B, 2C, the indoor heat exchanger 10A, IOB, 10C is supplied with refrigerant suitable for each required capacity. quantity is supplied. Therefore, the amount of heat dissipated in the indoor units 2A, 2B, and 2C is appropriately controlled according to the required capacity.

In addition, when a part of the heating is no longer needed, for example when the indoor unit B is no longer needed, turning off the operation switch of the controller 32B turns off the indoor fan IOC.
F. The flow rate control well 12C is throttled to an opening degree that corresponds to the amount of heat dissipated by natural convection.

Therefore, the pressure inside the indoor/outdoor heat exchanger 10B is the same as that of the gas side connecting pipe 13, and the temperature reaches the saturation temperature of this pressure, and heat is radiated indoors by slight natural convection. However, this amount of heat radiation is small, and since the flow rate control valve 12B is opened according to the amount of heat radiation due to natural convection, the interior of the indoor heat exchanger 10B becomes a gas-liquid two-phase flow, and the increase in the amount of liquid refrigerant is Therefore, the capacity of the liquid tank 8 may be small.

As described above, according to this embodiment, each indoor unit calculates the load of each room, sets the required capacity based on the load, and sets the flow control valve and compressor so that the refrigerant flow rate corresponds to the required capacity. Since the rotation speed is controlled, appropriate capacity can be supplied to each chamber,
Can accommodate differences in indoor unit capacity and load fluctuations in each room,
It always performs optimal capacity control and provides excellent comfort.

In this embodiment, the flow control valve is provided inside the indoor unit, but it can also be provided inside the outdoor unit or in the middle of the connecting pipe. Furthermore, it is possible to implement the method with three or more indoor units or even with two indoor units.

FIG. 5 is a control circuit diagram of a multi-room air conditioner according to another embodiment of the present invention, and FIG. 6 is a diagram showing the room temperature rise rate.

28A, 28B, 28C are storage units 34aA, 34aB
, 34aC is a changeover switch that changes the value of the room temperature increase rate ΔT/Δt stored in the memory.

The storage units 34aA, 34aB, and 34aC store two types of room temperature rise rates (8T/Δ) shown in FIG. 6 (i) and (ii).
t is stored as a function of the difference between the set temperature and the room temperature. Here, (i) is the room temperature rise rate during normal operation, (ii)
is the room temperature rise rate during rapid startup.

Indoor controller 37A in indoor units 2A, 2B, 2C,
From 37B and 37C, the required capacity of each room Q^+ Qa, Qc and indoor heat loss Q calculated in the same manner as the example in Figure 1
1^t Qta, Qtc are transmitted to the outdoor controller 28. The outdoor controller 28 calculates the compressor rotation speed from the total required capacity QT of each indoor unit and the temperature detected by the outside temperature sensor 23, and drives the compressor via the inverter circuit 24.

At this time, if the calculated compressor rotation speed exceeds the allowable rotation speed, the compressor is driven at the maximum allowable rotation speed, and the capacity Qmax of the outdoor unit at the maximum allowable rotation speed is calculated. The actual supply capacity is calculated by adding the required capacity of the indoor unit to the capacity Q.
The value obtained by multiplying the ratio of s a x to the total required capacity Qt, for example, the supply capacity QAO of the indoor unit 2A is Q^・Q.
&x/QT. At this time, if the supply capacity QAO is smaller than the indoor heat loss Qt^, the supply capacity QAO becomes the indoor heat loss Qi^, and the supply capacity to other indoor units decreases accordingly. This supply capacity is transmitted to each indoor unit and used as the required capacity, and the required capacity and capacity Q +a a.

The flow rate control valves 12A, 12B, and 12C are driven according to the ratio.

As described above, by controlling the multi-room air conditioner, the same operation as in the first embodiment is performed, but the changeover switch 38A of the frequently used indoor unit, for example, the indoor unit 2A, is set to By setting (n) to the rapid start-up and setting the other indoor units 2B and 2C to (i) during normal operation, the supply capacity of the indoor unit 2A is increased.
The set temperature is reached faster than other rooms.

Furthermore, some indoor units, for example, indoor unit 2
If the other two units are started with a large difference between the set temperature and the indoor temperature while the unit 2C is in operation, the amount of heat supplied to these two rooms will increase, and the amount of heat supplied to the indoor unit 2C will decrease.

However, the amount of heat supplied can be secured compared to the amount of heat lost indoors, and at least the current indoor temperature can be maintained.

As described above, according to this embodiment, the capacity distribution at the time of startup can be changed by setting the changeover switch, and control suitable for the usage state of the room in which the indoor unit is set becomes possible. Furthermore, even if the load on other rooms increases and the supply capacity to some indoor units decreases, at least the current indoor temperature can be maintained and comfort will not deteriorate.

In this example, the temperature increase rate was used as a coefficient for changing the required capacity, but the same effect can be obtained by changing the indoor heat capacity or the detected value of the difference between the set temperature and the indoor temperature. .

FIG. 7 is a control circuit diagram of a multi-room air conditioner according to still another embodiment of the present invention.

39A, 39B, 39C are operating devices 32A. 32B, 32
This is a quick switch that is provided in C and serves as a changeover switch for changing the value of the room temperature rise rate ΔT/Δt stored in the storage units 34aA, 34aB, and 34aC.When turned on, the switch selects the room temperature rise rate during rapid temperature rise. When the set temperature reaches the room temperature, it will automatically turn off.

By configuring as above, the quick switch 39A
, 39B, 39C (7) are all OFF (7), the same operation as in the embodiment of FIG. 1 of the present invention is performed.

Here, if air conditioning is suddenly required, for example, if it is necessary to quickly bring the room temperature of the indoor unit 2B to the set temperature, the required capacity can be increased by turning on the rapid switch 39B. , the set value is reached earlier than in other rooms, as in other embodiments of the present invention.

When the indoor temperature reaches the set value, the quick switch 39B will automatically turn off, and the next time the engine starts, it will return to normal operation.
Malfunctions caused by forgetting to turn off the quick switch 39B are eliminated.

As described above, according to this embodiment, the capacity distribution at the time of starting can be changed by turning on and off the quick switch provided on the controller, and the capacity distribution at the time of starting can be changed to suit the usage conditions of the room where the indoor unit is installed. Control becomes possible. Furthermore, even if the rapid switch is ON, it will automatically turn OFF when the indoor temperature reaches the drinking temperature, eliminating malfunctions caused by forgetting to turn it off.

〔Effect of the invention〕

According to the present invention, the required capacity can be set based on the calculated load, and appropriate capacity can be supplied to each room in order to control the flow rate control well and compressor rotation speed according to the required capacity, and the indoor unit capacity of each room is It can respond to differences in capacity and load chamber movements, and always performs optimal capacity control for excellent comfort.

[Brief explanation of drawings]

Fig. 1 is a control circuit diagram of a multi-chamber air conditioner according to an embodiment of the present invention, Fig. 2 is a refrigeration cycle diagram of the multi-chamber air conditioner of Fig. 1, and Fig. 3 is a time period of indoor temperature. FIG. 4 is a diagram showing the relationship between the difference between the set temperature and the indoor temperature and the room temperature rise rate. FIG. 5 is a control circuit diagram of a multi-room air conditioner according to another embodiment of the present invention. The figure is a diagram showing the relationship between the difference between the set temperature and the indoor temperature and the room temperature rise rate in the embodiment of Fig. 5, and Fig. 7 is a control circuit diagram of a multi-room air conditioner according to still another embodiment of the present invention. It is. 1... Outdoor unit, 2A, 2B, 2G... Indoor unit, 3... Compressor, 5... Outdoor heat exchanger, 7
...Expansion valve. 10A, IOB, IOC,... Indoor heat exchanger, 12A, 12B, 12C... Flow rate control valve, 23... Outside air temperature sensor, 24... Inverter circuit, 27... Expansion bowl drive device , 28... Outdoor controller, 30A, 30B, 30C... Indoor temperature sensor, 3
1A, 3 1 B, 31C...Set temperature, 32A
, 32B, 32C... operating device, 33A, 33B, 33
C... Arithmetic unit, 34A, 34B, 34C, 36A, 37A, 38B, 34aA, 34aB, 34aC--Storage unit, 36B,
36C...Flow control valve drive device, 3B, 37G...
Indoor controller, 38A, 38C... changeover switch, 3
9A, 39B, Kasumi No. 2 Kasumi 5-'! Datoi VJ Ne; Kurouse No. 3 Enpo 4 Mouth No. 51 ￥] Part b B

Claims (1)

[Scope of Claims] 1. A flow rate system comprising an outdoor unit having a variable capacity compressor and a plurality of indoor units connected to the outdoor unit, and capable of controlling the flow rate of refrigerant to the liquid side connection pipe of each indoor unit. A multi-room air conditioner equipped with a control valve is provided with means for detecting an indoor temperature, means for inputting a set temperature, and means for detecting a heat load of a room in which the indoor unit is installed, means for transmitting the required capacity calculated from the difference between the temperature and the set temperature and the heat load to the outdoor unit; a means for detecting the outside air temperature; A multi-room air conditioner, comprising: means for operating the compressor; and means for driving the flow rate control valve according to a ratio of required capacities of each of the indoor units.