JPH01212869A - Multichamber type air conditioner - Google Patents

Abstract

PURPOSE:To improve control stability, energy savingness and reliability, by a method wherein a pressure detector is located in a piping (in an outdoor machine) running between an indoor machine and a 4-way valve, and based on a combination step of the frequency and the number of poles of an inverter, both being predetermined according to a detecting pressure, a capacity combination step is decided. CONSTITUTION:A pressure detector is located in a piping (in an outdoor machine) running between an indoor machine and a 4-way valve, and an operation capacity deciding means is provided for deciding a capacity combination step based on a combination step of the frequency and the number of poles of an inverted, both being predetermined according to a detecting pressure therefrom. A capacity combination step wherein a differential is produced between capacities before and after the starting and the stop of a pole varying type compressor or change of the number of poles when capacity is increased and capacity is decreased is provided. A differential is produced between total capacities of two compressors during the starting and the stop of the pole varying type compressor and change of the number of poles. This constitution causes control of capacity to always improve controllability according to an air conditioning load and a present operation state at a relatively low given interval and without frequent change of the number of poles.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to capacity control of a multi-room air conditioner, particularly to wide capacity control.

Conventional technologyIn recent years, individual air conditioning has been progressing in building air conditioning.
In particular, individual air conditioning in multi-room air conditioners is attracting attention, and whether small-capacity indoor units can be connected depends on the ability control of the outdoor unit, that is, the compressor, and inverters are being actively adopted. It has started to be done.

An example of the conventional multi-room air conditioner mentioned above will be described below with reference to the drawings.

FIGS. 2 and 3 show a refrigeration cycle diagram and a block diagram of a conventional multi-room air conditioner. In Figure 2, 1
is a variable capacity compressor whose capacity can be varied by inverter 2,
3 is a pole variable compressor whose capacity can be varied by changing the number of poles of the motor using a pole number converter 4; 5 is an oil separator; 6 is a four-way valve that switches the heating and cooling cycle; 7 is an outdoor heat exchanger;
8 is an outdoor electric expansion valve, 9 is an accumulator, 10 is a refrigerant temperature sensor provided in a pipe on the opposite side of the outdoor heat exchanger 7 of the outdoor electric expansion valve 8, and 11 is provided in a pipe on the opposite side from the four-way valve 6. A pressure sensor 12 is an outdoor controller having an outdoor electric expansion valve controller 13 for controlling the outdoor electric expansion valve 8 and the like, and is provided in the outdoor unit 14. The oil separator 5 is connected to the accumulator 9 through an oil return pipe 16 equipped with a pressure reducer 16. Indoor unit 17A.

Each of 17B and 17C has an indoor heat exchanger 18A.
.

1sB, 18C, indoor electric expansion valve 19A, 19B.

19C1 The indoor electric expansion valves 19A and 19B.

Indoor electric expansion valve controller 21A that controls 19G.

21B, 2IC, set room temperature detector 22A, 22B.

22C1 Suction air temperature sensor 23A, 23B.

Indoor controllers 25A, 25B having 23C1 air conditioning load detectors 24A, 24B, 24C, etc.

It is equipped with 25C1 remote controllers 26A, 26B, and 26C.

The operation of the multi-room air conditioner configured as described above will be described below.

First, during cooling operation, the high-temperature, high-pressure gas refrigerant discharged from the variable capacity compressor 1 and extremely variable compressor 3, which are installed in parallel, is
The indoor units 17A flow into the outdoor heat exchanger 7 via the oil separator 5 and the four-way valve 6, are condensed and liquefied, and are connected in parallel via the outdoor electric expansion valve 8.

17B, 17C indoor electric expansion valves 2OA, 20B.

Depressurized at 20C, indoor heat exchanger 1sA, 1sB.

Evaporate at 18C, four-way valve 6, accumulator 9
It returns to the variable capacity compressor 1 and the extremely variable compressor 3 via.

In addition, during heating operation, the high-temperature, high-pressure gas refrigerant discharged from the variable capacity compressor 1 and the extremely variable compressor 3 flows into the indoor heat exchangers 1sA, 1sB, and 1sc via the oil separator 5 and the four-way valve 6, and is condensed. Liquefied, indoor electric expansion valve 2OA, 20B, 20
C, the pressure is reduced by the outdoor electric expansion valve 8, evaporated by the outdoor heat exchanger 7, and returned to the variable capacity compressor 1 and the polar variable compressor 3 via the four-way valve 6 and accumulator 9.

Next, capacity control and system control will be explained with reference to FIGS. 2 to 2. The capacity control of each compressor 1, 3 is performed according to the pressure detected by the pressure detector 11. During cooling, the low pressure side pressure is detected and the predetermined set low pressure is set, and during heating the high pressure side pressure is detected.
l), the pressure is set to a predetermined set high pressure, and the difference between the detected pressure and the set pressure is calculated by the pressure difference calculation means 27.
The inverter 2 and the pole number switch 4 are controlled by the capacity change determination and control means 28 which changes the combination steps of the capacity control combinations (Table 1) according to the pressure difference as shown in Table 2 (STEP 3, 5TEP4).

(Table 2) Correspondence table between pressure difference and capacity change width At this time, based on the capacity control combinations in Table 1, both normal compressors 1,
The relationship between the total capacities of 3 is shown in Figure 4 as υ.There is no overlap in the total capacity and at first glance the usage is efficient, but depending on the detection pressure, polar transformation compression is frequently observed. When the number of poles of machine 3 is changed, the control sag increases.
It is designed to have a control time interval ρ diffluence for step switching.

In each of the indoor units 17A, 17B, and 17C, indoor controllers 25A, 25B, and 25C measure the intake air temperature using intake air temperature detectors 23A and 23B.

23C detects 5TEP11), remote ':j:'
26A+26B, 26C set the respective room temperature set values Room temperature detectors 22A, 22B, 22
5TEP12), the air conditioning load is calculated from the room temperature set value and the intake air temperature by the air conditioning load calculators 24A and 24B.
.

24C (calculated at 5TEP1s), the valve opening degree changing determining means 29A, 29B determines that the valve opening degree of the electric expansion valve is being changed as shown in Table 3 according to the air conditioning load.

29C (STEP14), and control the indoor electric expansion valve controllers 21A, 21B, 2IC (5TEP1)
s).

Regarding the outdoor electric expansion valve 8, the valve opening degree is set to full open by the outdoor electric expansion valve controller 13 during cooling operation, and during heating operation,
In (STEP 21), the difference in temperature between the supercooled liquid refrigerant temperature in front of the outdoor electric expansion valve 8 detected by the refrigerant temperature detector 1o and the predetermined set refrigerant temperature is calculated by the refrigerant difference temperature calculation means 30, and is shown in Table 4. The outdoor valve opening changing determining means 31 determines when the outdoor electric expansion valve 8 is changing its opening as shown in FIG. 5TEP.
22) The outdoor electric expansion valve controller 13 controls the valve opening (STEP 23).

Problems to be Solved by the Invention However, in the above configuration, the control interval is adjusted so that the number of poles of the pole variable compressor does not change frequently, and the control interval is made to function as a differential. In view of the above problems, the present invention has developed a highly variable compressor. To provide a multi-room air conditioner that improves the controllability of capacity control operation that involves switching the number of poles, and improves the control stability, energy saving, and reliability of the room temperature of each indoor unit. Means for Solving the Problems In order to solve the above problems, the multi-room air conditioner of the present invention is equipped with a pressure detector in the piping (inside the outdoor unit) between the indoor unit and the four-way valve, and detects pressure in advance according to the detected pressure. It has an operation capability determining means for determining a capability combination step based on a predetermined combination step of the frequency and number of poles of the inverter,
It has a configuration that has a capacity combination step that has a differential in the capacity before and after the time of starting and stopping the pole variable compressor or changing the number of poles when increasing the capacity and when decreasing the capacity. 0 Effect The present invention has the above-described configuration, and by making the total capacity of the two compressors (capacity combination step) have a differential non-sharp ρ when the polar variable compressor starts and stops or changes the number of poles,
Capacity control is always performed at relatively small predetermined intervals according to the air conditioning load and current operating conditions, and there is no frequent change in the number of poles, improving controllability. Therefore, it is possible to control the room temperature of each indoor unit. This will improve stability, energy savings, and reliability.

EXAMPLE Below, a multi-room air conditioner according to an embodiment of the present invention will be explained with reference to the drawings. ◎ Regarding the system configuration and control, the same numbers will be given to the same parts as in the conventional example, and the explanation will be omitted. .

The basic concept of capacity control for the two compressors 1 and 3 is the same, but as shown in Table 5 and Figure 1,
Regarding the capacity control combination and the total capacity, a differential p is provided before and after the capacity where the number of poles of the polar variable compressor 3 is switched.

The other configuration, control and operation are the same as the conventional example.

As described above, according to this embodiment, a pressure detector is provided in the piping (inside the outdoor unit) between the indoor unit and the four-way valve, and the inverter frequency and number of pole combination steps are predetermined according to the detected pressure. The driving capability determining means determines the capability combination step based on the following. Then, by providing a capacity combination step that has a differential in the capacity before and after the time of starting/stopping the pole variable compressor or changing the number of poles when increasing the capacity and when decreasing the capacity.
By providing a differential for the total capacity (capacity combination step) of the two compressors at the time of turning on/off or changing the number of poles of the polar variable compressor, the capacity can be constantly controlled at relatively small predetermined intervals to adjust the air conditioning load or It is possible to improve controllability according to the current operating conditions and without frequent changes in the number of poles, thereby improving the control stability, energy saving, and reliability of the room temperature of each indoor unit. Possible Effects of the Invention As described above, the present invention provides a pressure detector in the piping between the indoor unit and the four-way valve, and calculates the pressure based on the combination step of the frequency and number of poles of the inverter predetermined according to the detected pressure. It has an operating capacity determination means for determining the capacity combination step, and has a differential between the capacities before and after the time of starting and stopping the polar variable compressor or changing the number of poles when increasing the capacity and decreasing the capacity. By providing a capacity combination step, the total capacity of the two compressors (capacity combination step) can be controlled at all times by providing a differential when the polar variable compressor is turned on/off or when changing the number of poles. Controllability is improved by responding to the air conditioning load and current operating conditions at relatively small predetermined intervals, and without frequent changes in the number of poles, resulting in stable control of the room temperature of each indoor unit.

Can improve energy saving and reliability0

[Brief explanation of the drawing]

A system configuration diagram of a conventional multi-room air conditioner, Fig. 3 is a block diagram of the same, Fig. 4 is a diagram of the compression function force combination step and total capacity, and Fig. 6 is a flowchart of the indoor electric expansion valve control section. , FIG. 6 is a flowchart of the outdoor functional force control section, and FIG. 7 is the outdoor electric expansion valve control section. 1... Capacity variable compressor, 2... Impark, 3... Extremely variable compressor, 11... Pressure detector. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 3, Figure 4, Figure 5, Figure 5, 〈! Uchiiso ＼〉 Fig. 6〈Outdoor a consideration hill force combination υ4D fall〉 Fig. 7 ＜1pHMsts＊+n=9

Claims (1)

[Claims] One outdoor unit equipped with a compressor whose capacity can be varied by an inverter, a pole-change compressor, an oil separator, a four-way valve, an outdoor heat exchanger, an outdoor electric expansion valve, and an accumulator, an indoor electric expansion valve, and an indoor electric expansion valve. A plurality of indoor units, each equipped with a heat exchanger, are connected in parallel, a pressure detector is installed in the piping inside the outdoor unit between the indoor unit and the four-way valve, and the pressure is determined in advance according to the detected pressure. It has an operation capacity determination means that determines the capacity combination step based on the frequency and pole number combination step of the inverter, and the pole variable compressor is started and stopped or the pole number is changed when the capacity is increased and when the capacity is decreased. A multi-room air conditioner characterized by having a capacity combination step with a differential in capacity before and after.