JPS60138349A - Air conditioner - Google Patents

Abstract

PURPOSE:To decrease a fluctuation in a room temperature and to enable saving of energy, by a method wherein the performance of a compressor is controlled according to a change in an air conditioning load due to a change in an outdoor temperature. CONSTITUTION:A capacity varying compressor 1, an outdoor heat exchanger 3, a pressure reducer 4, and an indoor heat exchanger 5 are intercommunicated to form a refrigerating cycle. The output of an inverter device 8, acting as a driving device for the compressor 1, is controlled by means of a capacity control signal from a controller 15. A computing means 16 determines a temperature difference between a room temperature setting circuit 11 and a room temperature sensor 12 from outputs therefrom, and a deciding means 18 decides a belonging zone according to such temperature difference. A zone pattern selecting means 13 selects an optimum zone pattern from 3 kinds of zone patterns previously stored based on the detecting temperature of the temperature sensor 13. An output means 19 outputs, in a zone pattern selected by a zone pattern selecting means 17, a capacity control signal responding to the output frequency of an inverter device set according to a belonging zone decided by the zone determining means 18.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an air conditioner equipped with a variable capacity compressor.

[Technical background of the invention and its problems]

Currently, the number of air conditioners equipped with a variable capacity compressor, which is excellent in terms of improved air conditioning comfort and energy saving, is increasing. Such an air conditioner is shown in Japanese Patent Laid-Open No. 57-67735.

Therefore, this air conditioner will be explained with reference to FIGS. 1, 2, and 3.

This air conditioner is a heat pump type air conditioner capable of cooling and heating, with 1 variable capacity compressor and 2 four-way valves for switching between cooling and heating.
, an outdoor heat exchanger 3, a pressure reducing device 41, and an indoor heat exchanger 5 connected in sequence through piping, and a refrigeration cycle and an indoor fan 6.
, and an outdoor fan 7.

The variable capacity compressor 1 uses the output of the inverter device 8 as a power source for the compressor motor 9. Therefore, by changing the output of the inverter device 8, that is, the frequency of the pseudo sine wave alternating current, the rotation speed of the compressor motor 9 is changed, and the capacity of the compressor is increased or decreased.

The frequency of the AC output of the inverter device 8 is determined by comparing the outputs of a room temperature sensor 10 made of a thermistor that detects the room temperature and a room temperature setting circuit 110 that allows the user to manually set the room temperature.

In this air conditioner, this comparison/determination is performed by a microcomputer, R
This is performed by a control device 12 that is composed of an OM, a RAM, etc., and receives a room temperature sensor 10 and a room temperature setting circuit 11 as inputs. The control device 12 first detects the difference between the detected room temperature and the set temperature. Then, it is determined which of the pre-stored temperature difference zones this difference value belongs to, and depending on the zone to which it belongs, a frequency command signal that is pre-stored corresponding to the zone is output to the inverter device 8. do.

The relationship between this zone and frequency is shown in FIG. 2, taking the case of cooling operation as an example.

In the figure, there is a temperature difference of 1@ in zones a, b, c, d, and e, and a frequency of 0 in each zone a, b, c, d, and e.
．． Nu, N2, N3, and N4 correspond, and 0<Nl<
N2<N3<N4.

For this reason, the temperature difference is wide (zone a) and the capacity is high (N4),
When the temperature difference is small (zone b), the capacity is low (Nl), and operation is performed with good room temperature control according to the air conditioning load.

However, the capacity of an air conditioner is not determined only by the compression function (output frequency of the inverter device), but also depends on the outdoor temperature. This relationship is shown in Table 1 (during cooling).

Table 1 As can be seen from Table 1, there is an inversely proportional relationship between the outdoor temperature and the capacity of the air conditioner. (Note that during heating operation, the relationship is proportional.) Furthermore, the relationship between air conditioning load and outdoor temperature is proportional (inversely proportional during heating operation). Therefore, Figure 3 shows the changes in the air conditioner's capacity and air conditioning load with respect to the outdoor temperature when the output of the inverter device corresponding to the zone is set so that the air conditioner can provide sufficient cooling even at an outdoor temperature of 35°C. show.

In this case, if the outdoor temperature is a low value of 35℃ or less,
The capacity of the air conditioner at each frequency N1 to N4 increases, and conversely, the air conditioning load decreases, so the capacity becomes excessive with respect to the air conditioning load, and the rate of decrease in room temperature becomes faster.

As a result, the room temperature is partially supercooled, resulting in poor temperature distribution and causing discomfort to the user. In addition, the room temperature decreases faster than the response of the room temperature sensor, causing a delay in the control that reduces the capacity in response to the decrease in the room temperature, and even if the air conditioning load and capacity are balanced at frequency Nl, the room temperature will stop due to the delay in response. Rushing into sea y (zone a), 0N
There were drawbacks such as 10FF operation and operation with large room temperature fluctuations.

In addition, in this case, unnecessary high-capacity operation time becomes longer and power consumption also increases.

[Purpose of the invention]

The present invention reduces room temperature fluctuations by controlling the capacity of an air conditioner, that is, the capacity of a variable capacity compressor, in response to changes in air conditioning load due to changes in outdoor temperature.
The purpose is to provide an air conditioner that can operate in an even more energy-efficient manner.

[Summary of the invention]

In an air conditioner equipped with a variable capacity compressor, the present invention provides a control device that outputs a predetermined capacity control signal based on a room temperature setting device, a room temperature sensor, and an outdoor temperature, and the ability to command the capacity control signal. The air conditioner is equipped with a drive device that drives a variable capacity compressor, and a drive device that drives a variable capacity compressor.

[Embodiments of the invention]

A first embodiment of the present invention will be described with reference to FIGS. 4, 5, and 6. Note that the same parts as those in FIG. 1, which is a conventional example, are designated by the same reference numerals.

The air conditioner of this embodiment has a refrigeration cycle in which a variable capacity compressor 1, a pressure valve 2, an outdoor heat exchanger 3, a pressure reducing device 4, and an indoor heat exchanger 5 are connected in sequence, similar to the conventional one. ing. An inverter device 8 is provided as a drive device for driving the compressor motor 9 of the variable capacity compressor 1.

The output of this inverter device 8 is controlled by a capacity control signal from a control device 15 that receives a room temperature setting circuit 17, a room temperature sensor 12, and an outdoor temperature sensor 13 that detects the outdoor temperature.

The control device 15, which includes a microcomputer, will be described in detail below according to the functional block diagram shown in FIG. The control device 15 is
A calculation means 16 which receives the room temperature setting circuit 11 and the room temperature sensor 12 as inputs, a zone judgment means 18 which receives the calculation means 16 as inputs, a zone pattern selection means 17 which receives the outdoor temperature sensor 13 as input, and zone pattern selection means 17. It is composed of an output means 19 which receives the zone determination means 18 as an input and outputs a capacity control signal to the inverter device 8.

The operation of each of these means will be explained below. First, calculation means 1
6 calculates the temperature difference from the outputs of the room temperature setting circuit 11 and the room temperature sensor 12 and outputs the result. And zone determination means 18
determines the zone to which it belongs based on this temperature difference. In this embodiment, the zones are a, b, c, d, e, as shown in FIG.
It is divided into ≧77 stages of f and g. Also, the zone? (The pattern selection means 13 selects the optimum zone pattern from three types of zone patterns stored in advance based on the temperature detected by the outdoor temperature sensor 13.

Table 2 shows this zone/cutan.

The same zone pattern shows the case of cooling operation, and 0<N
l<N2<N3<N4.

Table 2 That is, in this embodiment, three types of zone patterns, pattern E, ■, and ■0, are stored, and each zone in each zone pattern is set with an inverter device output frequency, which is a capacity control value. There is. Then, the pattern selection means 13 selects pattern I, 28 when the outdoor temperature is 35°C or higher.
Select Pattern I at ~34℃ and Pattern ■ below 27℃.

Note that the inverter device output frequencies set corresponding to each zone in each of these zone patterns are low (in the order of patterns I, I, and ■).

In other words, the capacity of the air conditioner is set to decrease earlier as the outdoor temperature decreases.

Finally, the output means 19 outputs the zone pattern selected by the zone pattern selection means 17 to the zone judgment means 1.
A capability control signal is output in accordance with the inverter device output frequency set corresponding to the zone to which it belongs determined in step 8.

Then, the inverter device 8 outputs an AC output at a frequency commanded by the capacity control signal from the output means 19, and the air conditioner is operated at a predetermined capacity.

To give an example of the operation of the air conditioner of this embodiment, when the outdoor temperature is 29°C, the room temperature is 29.5°C, and the set temperature is 26°C, the difference between the room temperature and the set temperature is 3.5°C, and the zone to which it belongs is room temperature. If it is descending, it is determined to be an e-zone, and if it is ascending, it is determined to be a pattern. Furthermore, as for the zone pattern, Pattern I remains from outdoor air IM 29°C. As a result, N a (H
2) If it is rising, a capacity control signal of N 2 (H2) is sent to the inverter device 8. Also, if other conditions are the same and the outdoor temperature is 35°C or higher, the zone pattern is pattern E, and N4 is the case when the room temperature is falling and when the room temperature is rising.
(H2) capability control signal is sent.

As described above, according to this embodiment, when the outdoor temperature is low, the capacity of the air conditioner is reduced early when the room temperature approaches the set room temperature. This improves room temperature controllability, enables air conditioning with less room temperature fluctuation, and eliminates unnecessary high-capacity operation (1r more energy saving effect).

Furthermore, although the above description has been made with reference to the cooling operation, the higher the outdoor temperature is during the heating operation, the similar effect can be obtained by lowering the inverter output frequency for each zone.

Next, a second embodiment will be explained with reference to FIG.

This embodiment has the same configuration as the first embodiment shown in FIG. 4, except for the control device 15.

The control device 15 includes a calculation means 16 which receives the room temperature setting circuit 11 and the room temperature sensor 12 as inputs, a temperature difference correction means 20 which receives the calculation means 16 and the outdoor temperature sensor 13 as inputs, and a zone which receives the temperature difference correction means 20 as inputs. The control device 15 is composed of a determining means 18 and an output means 19 which receives the zone determining means 18 as an input and issues a capacity control signal to the inverter device 8. Each means constituting the control device 15 will be described below. The calculating means 16 calculates the difference between the set temperature of the room temperature setting circuit 11 and the room temperature detected by the room temperature sensor 12. And temperature difference correction means 20
is the temperature difference determined by the calculating means 16 and the outdoor temperature sensor 13
and outputs the corrected temperature difference to the zone determining means 18. This correction by the temperature difference correction means 20 is performed using the following equation.

T=αTl) where, α: correction coefficient, Tp: temperature detected by outdoor temperature sensor,
t: difference between set room temperature and detected room temperature, T: temperature difference after correction.

Next, the zone determining means 18 stores only one zone pattern, similar to the conventional one, and determines the zone to which the corrected temperature difference belongs in that zone pattern. Then, the output means 19 outputs a capacity control signal according to the inverter device output frequency corresponding to the zone determined by the zone determination means 18 in this zone pattern. Thereafter, based on this capacity control signal, similar to the first embodiment (
Capacity control of the air conditioner is performed.

According to the second embodiment, the difference between the set room temperature and the detected room temperature is corrected based on the outdoor temperature, and the capacity of the air conditioner is determined based on the difference after this correction. This enables air conditioning with high performance and minimal room temperature fluctuations.

Furthermore, in this embodiment, it is sufficient to store only one type of zone pattern as in the conventional case, and the ROM is
There is no need to increase the capacity (it also has practical effects).

Further, in the first and second embodiments, the outdoor temperature is directly detected by the outdoor temperature sensor, but the outdoor temperature may be indirectly detected from the outdoor heat exchanger temperature.

In this case, the heat pump type air conditioner has the advantage that the outdoor heat exchanger temperature sensor provided in the defrosting basin can be used also.

〔Effect of the invention〕

The present invention controls the air conditioning load determined by the difference between the room temperature and the set temperature and the outdoor temperature by fully following the capacity of the variable capacity compressor, thereby reducing unnecessary high capacity operation time and reducing room temperature fluctuations. This has the effect of making it possible to achieve a comfortable nitrous tone.

[Brief explanation of the drawing]

Figure 1 shows the refrigeration cycle and control block of an air conditioner equipped with a conventional variable capacity compressor, and Figure 2 shows the refrigeration cycle and control block of an air conditioner equipped with a conventional variable capacity compressor. Figure 3 is a graph showing changes in air moisturizing phase function and air conditioning load with respect to outdoor temperature;
The figure shows the refrigeration cycle and control block of the air conditioner according to the first embodiment of the present invention, FIG. 5 is a control block diagram of the air conditioner, and FIG. 6 shows the temperature difference of the air conditioner. Diagram showing zones divided by room temperature changes and time, No. 7
The figure is a control block diagram of an air conditioner according to a second embodiment of the present invention. 1... Variable capacity compressor 2... Four-way valve 3... Outdoor heat exchanger 4... Pressure reducing device 5... Indoor heat exchanger 8
... Inverter device 9 ... Compressor motor 11 ...
- Room temperature control circuit 12...Room temperature sensor 13...Outdoor temperature sensor 15...Control device 16...Calculating means 1
7...Zone pattern selection means 18...Zone judgment means 19...Output means 20.
...Temperature difference correction means Fig. 2 (0C) Fig. 6 Fig. 7

Claims (1)

[Claims] 1. A refrigeration/freezing cycle in which a variable capacity compressor, an outdoor heat exchanger, a pressure reduction device, an indoor heat exchanger, etc. are connected in sequence;
A room temperature setting device that sets the room temperature, a room temperature sensor that detects the room temperature, an outdoor temperature sensor that detects the outdoor temperature or the outdoor heat exchanger temperature, and a difference between the set room temperature and the detected room temperature and the detected temperature of the outdoor temperature sensor. 1. An air conditioner comprising: a control device that outputs a capacity control signal based on the variable capacity compressor; and a drive device that drives the variable capacity compressor to a predetermined capacity in accordance with the capacity control signal output from the control device. 2. The control device includes a calculation means for calculating the difference between the set temperature and the detected room temperature, and a calculation means to which the difference found by the calculation means belongs to one of a plurality of zones divided by the variation range of the difference between the set temperature and the sensed room temperature. A zone judgment means for determining whether the outdoor temperature sensor is zone pattern selection means for selecting one zone pattern according to the zone pattern selection means; The air conditioner according to claim 1, characterized in that the control device comprises an output means for outputting a capacity control signal.3. temperature difference correction means for correcting the difference value obtained by the calculation means according to the temperature detected by the outdoor temperature sensor;
zone determining means for dividing the range of variation of the difference between the set room temperature and the detected room temperature into a plurality of zones, and determining to which zone the difference after correction obtained by the temperature difference correcting means belongs; The air conditioner according to claim 1, further comprising output means for outputting a capacity control signal corresponding to the determined zone.