JP2000291995A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the stoppage of a compressor under a condition, such as low heating load or the like in which high pressure is apt to increase. SOLUTION: When it is decided that air conditioning load in heating cycle is low, acceleration of the rotating speed of a compressor 13 is suppressed more than when it is decided that the air conditioning load is high. Thus, at low heating load, acceleration of the rotating speed of the compressor 13 is suppressed. Accordingly, at low heating load, the rotating speed of the compressor 13 can be prevented from overshooting relative to a target rotating speed. Then, the stoppage of the compressor due to overshooting of the speed of rotation of the compressor 13 can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat pump air conditioner having a compressor with a built-in electric motor, and more particularly to an improvement in control for preventing the compressor from stopping at a low heating load. ).

[0002]

2. Description of the Related Art A conventional heat pump type air conditioner for a vehicle is disclosed in, for example, Japanese Patent Application Laid-Open No. 9-220924. This prior art employs a control method for uniquely changing the blower level in accordance with the value of the high pressure, regardless of the rising speed of the high pressure, as the cold air prevention control when the heat pump starts heating.

[0003]

By the way, when the heating is at a low load such as when the outside air temperature is high, the high pressure tends to rise. At such a low heating load, if the blower level is determined based on a characteristic uniquely determined according to the value of the high pressure without considering the rising speed of the high pressure, high pressure overshoot with respect to the target high pressure can be avoided. May not be. When the high-pressure overshoot occurs, the compressor may stop, which causes a decrease in the temperature of the heating air blown out, which significantly deteriorates the heating feeling.

In order to prevent the compressor from stopping due to the high pressure overshoot, the characteristics are changed so that the rate of change of the blower level with respect to the change of the high pressure is increased, and the load on the compressor may be increased as the high pressure increases. Can be However, if the unique characteristics are determined in this way, at the time of a high heating load such as when the outside air temperature is low, the blower level increases quickly, so that the cool air having a low temperature of the heating heat source is blown out, There is a problem that the feeling is impaired, and there is no adaptability to the heating load.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to prevent a compressor from being stopped under conditions in which high pressure is likely to increase, such as when heating is under a low load. And

[0006]

To achieve the above object, according to the first aspect of the present invention, a blower (7) for generating an air flow, and an air conditioning duct for guiding the air generated by the blower (7) to a room. (2) and a compressor (1) that compresses and discharges refrigerant.
3) a condenser (9) arranged in the air conditioning duct (2) for heating the conditioned air during heating, a decompression means (19) for decompressing the refrigerant condensed in the condenser (9), and an outdoor unit. An outdoor heat exchanger (1) which is disposed in
8) during the heating cycle, the compressor (13) →
Condenser (9) → decompression means (19) → outdoor heat exchanger (1
8) → In the air conditioner in which the refrigerant flows through the path of the compressor (13), the outdoor heat exchanger (18) acts as an evaporator and the conditioned air is heated by the condenser (9).
Further, load determining means (24, S107, S407, S507) for determining the air-conditioning load during the heating cycle, and compressor rotational speed controlling means (2) for controlling the rotational speed of the compressor (13).
2), and load determining means (24, S107, S40)
7, S507), when the air-conditioning load during the heating cycle is determined to be low, the compressor speed control means (22, 2, 2) is compared to when it is determined to be high.
4) is characterized in that the rotational speed of the compressor (13) is suppressed from increasing.

[0007] According to this, when the heating is under a low load, the rotational speed increasing speed of the compressor (13) is suppressed. for that reason,
At the time of heating low load, it is possible to prevent the rotation speed of the compressor (13) from overshooting the target rotation speed. Then, it is possible to prevent the compressor from being stopped due to overshoot of the rotation speed of the compressor (13).

In addition, when the heating load is high, there is little danger that the rotation speed of the compressor (13) will overshoot the target rotation speed.
It is larger than at low load, making it possible to accelerate the temperature rise of the heating heat source. According to the second aspect of the present invention, there is provided an air volume control means (24) for controlling the air volume of the blower (7), and the load determination means (24, S107, S4).
07, S507), when the air-conditioning load during the heating cycle is determined to be low, the air volume control means (24) controls the air flow of the blower (7) compared to when the air-conditioning load is determined to be high. It is characterized in that the air volume increasing speed is increased.

According to this, the load determining means (24, S1
07, S407, and S507), when the air conditioning load during the heating cycle is determined to be low, compared to when the air conditioning load is determined to be high, the air flow control means (2
4) increases the rate of increase in the amount of air blown by the blower (7).
Then, by increasing the air flow, the compressor (1
The load of (3) is increased, the rotation speed increases rapidly, and overshoots the target rotation speed and the compressor (1)
3) can be prevented from stopping. Also,
When the heating load is high, the rate of increase of the air flow rate is reduced, so that the cooling air with a low temperature of the heating heat source is prevented from rapidly blowing out at the time of the heating load, thereby preventing the feeling from being deteriorated.

When the load determining means (24, S107, S407, S507) determines that the air-conditioning load during the heating cycle is low, the compressor rotational speed may be reduced. It is also possible to change the control characteristics of both the control means (22, 24) and the air volume control means (24). The determination of the air-conditioning load at the time of the heating cycle is based on the quantity related to the outside air temperature (β) and the deviation (E _n ) between the target high pressure (SPO) and the high pressure (SP), as in the invention of claim 4. Based on at least one of
It is possible to do.

The reference numerals in parentheses of the above-mentioned means indicate the correspondence with the concrete means described in the embodiments described later.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 shows a cycle in a heating mode in a first embodiment in which the present invention is applied to an air conditioner for an electric vehicle.

In FIG. 1, an air conditioning unit 1 is installed in a passenger compartment of an electric vehicle.
It constitutes an air-conditioned air passage for guiding the conditioned air into the vehicle interior. At one end of the air-conditioning duct 2, there is provided an inside air suction port 3 for sucking inside air and an outside air suction port 4 for sucking outside air, and the two suction ports 3, 4 are selectively opened and closed by an inside / outside air switching door 5. .

A blower 6 for blowing air into the air-conditioning duct 2 is installed adjacent to the inlets 3 and 4, and the blower 6 is constituted by a centrifugal fan driven by a motor 7. In the air conditioning duct 2, a cooling evaporator 8 is provided on the air blowing side of the blower 6. The cooling evaporator 8 is an indoor heat exchanger that forms a part of a refrigeration cycle, and cools the air in the air conditioning duct 2 by absorbing the refrigerant flowing inside during a cooling mode and a dehumidifying / heating cycle described below. Functions as a cooler to dehumidify.

A heating condenser 9 is provided downstream of the cooling evaporator 8 in the air. The heating condenser 9 is also an indoor heat exchanger that constitutes a part of the refrigeration cycle, and heats the air in the air conditioning duct 2 by the heat radiation action of the refrigerant flowing inside during the heating cycle and the dehumidifying heating cycle described below. It functions as a heater. In the air-conditioning duct 2, a bypass passage 10 is provided on the side of the heating condenser 9 to bypass the heating condenser 9 and flow air.
A plate-like switching door 11 for switching between a ventilation passage of the heating condenser 9 and a bypass passage 10 is rotatably provided.
The switching door 11 is operated at a solid line position for fully opening the ventilation passage of the heating condenser 9 and completely closing the bypass passage 10 during heating, and closing the ventilation passage of the heating condenser 9 completely for cooling during cooling. It is operated to the dashed line position where 10 is fully opened.

After passing through the heating condenser 9 or the bypass passage 10, the conditioned air is blown into the vehicle interior. Here, the plurality of outlets leading to the vehicle interior are conventionally known,
A foot outlet for blowing conditioned air toward the foot of the passenger in the passenger compartment, a face outlet for blowing conditioned air toward the upper body of the passenger in the passenger compartment, and a defroster outlet for discharging conditioned air to the inner surface of the vehicle window glass are provided. The plurality of outlets are switched and opened / closed by a not-shown outlet mode door.

Next, the refrigeration cycle 12 including the cooling evaporator 8 and the heating condenser 9 will be described. The refrigeration cycle 12 is configured as a heat pump refrigeration cycle for cooling and heating the vehicle interior. , A motor-driven refrigerant compressor 13. In the flow path between the discharge side of the compressor 13 and the condenser 9, a pressure sensor 14 for detecting a discharge pressure (cycle high pressure) is arranged.

Further, the refrigeration cycle 12 includes a cooling solenoid valve 15, a heating solenoid valve 16, a dehumidification solenoid valve 17, an outdoor heat exchanger 18, a first decompressor 19, a second depressurizer 20, and a refrigerant gas. An accumulator 21 that separates the liquid, stores the liquid refrigerant, and discharges the gas refrigerant is provided. The outdoor heat exchanger 18 is installed outside the vehicle compartment of the electric vehicle, and exchanges heat with the outside air blown by the electric outdoor fan 18a. In addition, the refrigerant compressor 13
Is an electric compressor, in which an electric motor (AC motor) (not shown) is integrally incorporated in a sealed case, and driven by this motor to perform suction, compression and discharge of the refrigerant.

An AC voltage is applied to the AC motor of the refrigerant compressor 13 by an inverter 22, and the frequency of the AC voltage is adjusted by the inverter 22 to continuously change the motor rotation speed.
Accordingly, the inverter 22 serves as a means for adjusting the rotation speed of the compressor 13, and a DC voltage is applied to the inverter 22 from the vehicle-mounted battery 23.

The inverter 22 is energized and controlled by an air conditioning controller 24. This air conditioning control device 24
Is an electronic control unit composed of a microcomputer and its peripheral circuits.
-17 are controlled. In this example, the solenoid valves 15 to 17
Constitutes a path switching means for switching the refrigerant path.

Although FIG. 1 does not show the electrical connection with the air-conditioning control device 24, devices such as the inside / outside air switching door 5, the blower 6, the aermic door 11, and the outdoor fan 18a of the air-conditioning unit 1 are also provided. The operation is controlled by the control device 24. The control device 24 includes the pressure sensor 1 described above.
4, an outside air temperature sensor for detecting the outside air temperature, an inside air sensor for detecting the temperature in the passenger compartment, an evaporator temperature sensor for detecting the air temperature immediately after the blowing of the cooling evaporator 8, and a detection of the amount of solar radiation into the passenger compartment A sensor signal is input from an air conditioning sensor group 25 including a solar radiation sensor and the like. Further, signals (temperature setting signals and the like) from the levers and switches 27 of the air conditioning operation panel 26 provided near the driver's seat in the vehicle cabin are also input to the control device 24.

Next, the operation of the first embodiment in the above configuration will be described. FIGS. 2 to 4 show a control routine executed by the microcomputer of the control device 24. When the switch is turned on, the control routine in FIG. 2 starts, initialization is performed in step S101, and signals from the sensor group 25 and the air conditioning operation panel 26 in FIG.

Next, at step 103, the operation mode of the air conditioner is determined. The method of determining the operation mode is the same as that of Japanese Patent Application Laid-Open No. 8-337108 filed by the present applicant, and calculates the target blow-off air temperature TAO (° C.) required to maintain the passenger compartment at the set temperature of the occupant. And this TAO
(T) between the air temperature Tin (° C.)
AO-Tin) is calculated, and this deviation (TAO-Tin) is calculated.
Operating mode (ie, cooling mode,
Heating mode and air blowing mode). Specifically, when the deviation (TAO-Tin) is in the intermediate region, the air blowing mode is set. When the deviation (TAO-Tin) is larger than the intermediate region, the air conditioning mode is set.

Then, in step 104, it is determined whether or not the heating mode is set. In the heating mode, the cooling solenoid valve 15 and the dehumidifying solenoid valve 17 of the refrigeration cycle 12 are closed by the output of the control device 24, and the heating solenoid valve 1 is closed.
6 is opened. Thereby, when the compressor 13 operates, the path shown by the thick line in FIG. 1, that is, the compressor 13 → the condenser 9 → the first depressurizer 19 → the outdoor heat exchanger 18 → the heating electromagnetic valve 18 → the accumulator 21 → the compression. The refrigerant flows through the path of the machine 13.

Therefore, the outdoor heat exchanger 18 = evaporator, and the heat absorbed by the outdoor heat exchanger 18 and the heat generated by the compression work can be radiated as condensation heat in the indoor condenser 9 in the air conditioning unit 1. it can. Therefore, the switching door 1
1 is opened as shown by the solid line in FIG.
Blown air passes through the condenser 9 and is heated to become hot air, so that the vehicle interior can be heated.

At this time, a small amount of refrigerant flows into the indoor evaporator 8 in the air conditioning unit 1 via the second decompressor 20 and can be evaporated there. Can dehumidify the blown air to some extent. If it is determined in step 104 that the heating mode is set, in step 105, the target saturation temperature TCO
(° C.) is calculated by the following Equation 1.

[0027]

TCO = (TAO−Tin) / Φ + Tin Here, Φ is a temperature efficiency determined from the air volume of the air passing through the condenser 9. Next, in step 106,
The target high pressure SPO (kg / cm ² G) is calculated. The target high pressure SPO (kg / cm ² G) is calculated from the TCO based on a map stored in a ROM (not shown) in the ECU 24.

Next, at step 107, it is determined whether or not the outside air temperature detected by the outside air temperature sensor is equal to or higher than β (° C.). When the determination result in step 107 is No, that is, when the outside air temperature is smaller than β (° C.), the process proceeds to step 108, in which the target compressor rotation speed is calculated by heating fuzzy control, and the first compressor rotation speed is controlled. High pressure fuzzy control is performed. When the result of the determination in step 107 is Yes, that is, when the outside air temperature is equal to or higher than β (° C.), the process proceeds to step 109 to perform the second high-pressure fuzzy control.

FIG. 3 shows a first high-pressure fuzzy control subroutine for controlling the compressor speed when the determination result in step 107 is No. First, step 20
At 0, cold air prevention control is performed. This cold air prevention control is well-known, for example, performed based on a characteristic diagram as shown in FIG. To briefly explain the cool air prevention control, the cool air prevention control is started when the heating mode is selected when the IG switch is ON or when the heating mode is selected again after the heating switch is turned off.

During the cool air prevention control, the target rotation speed of the compressor 13 is fixed at 9000 rpm in order to speed up the heating rise, and the rotation speed increasing speed is MAX (= 150 rpm).
pm / sec). During the cold air prevention control, a fuzzy rule described later is not applied. The blower level during the cold air prevention control is determined based on the high pressure SP detected by the pressure sensor 14 based on the characteristic diagram of FIG.

The cold air prevention control is performed 5 seconds after the start of the cold air prevention control.
When minutes have passed, SPO-SP ≦ 2 or SP> 13
(If the heating mode is selected again after the heating switch is turned off, SP> 7), the condition is released when any one of the conditions is satisfied. After the cold air prevention control in step 200 is canceled, the process proceeds to step 201. In step 201, it is determined whether a predetermined control cycle (control timing: for example, 4 seconds) has elapsed. If the determination result of step 201 is No, step 2
07 is controlled. If the determination result of step 201 is Yes, the deviation E between the SPO calculated in step 106 and the high pressure SP detected by the pressure sensor 14 is determined.
_n (kg / cm ² G) is calculated by the following equation (Step 202).

[0032]

[Number 2] Next E _n = SPO-SP, at step 203, calculates a deviation change rate ^{_{E dot (kg / cm 2 G}} ) based on the equation 3 below.

[0033]

Equation 3] where _{E dot = E n -E n-} 1, for E _n is updated, for example, every 4 seconds, E _n-1
It has a value of 4 seconds before against E _n. Next, step 20
In step 4, CF1 and CF2 are obtained from the membership functions shown in FIGS. 6A and 6B stored in Rom.

Next, at step 205, the ROM
Memberships shown in FIGS. 6A and 6B stored in
Using functions and well-known rule tables stored in ROM
Based on the fuzzy inference, the rotation speed of the compressor 13 four seconds ago
Degree f_n-1(Rpm) the rotational speed Δf (r
pm / sec). Thus, E_nAnd E
_dotIs determined based on the target rotation speed f _nTo
It is calculated based on the following Equation 4. (Step 206)

[0035]

F _n = f _{n -1} + Δf Next, the actual rotation speed of the compressor 13 becomes the target rotation speed f _n.
In step 207, the inverter 2
2 is energized. As described above, step 107
Is negative, that is, when the outside air temperature is lower than β (° C.), the compressor speed control is performed.

FIG. 4 shows the second case where the determination result in step 107 is Yes, that is, when the outside air temperature is β (° C.) or more.
It is a subroutine for controlling the compressor speed in the high-pressure fuzzy control. The processing from step 300 to step 305 in FIG. 4 is the same as the processing from step 200 to step 205 in FIG. In step 306, a constant C to be multiplied by Δf determined in step 305 is determined. The constant C is a multiplier for reducing Δf by a predetermined ratio, and is determined by, for example, the characteristic diagram of FIG. FIG. 7 shows a characteristic diagram for determining the constant C according to the outside air temperature. In the example of FIG. 7, when the outside air temperature is lower than β (° C.) (for example, 15 ° C.), the constant C is set to 1.0. On the other hand, when the outside air temperature is higher than γ (° C.) (for example, 18 ° C.), the constant C is set to 0.5. When the outside air temperature is equal to or more than β (° C.) and equal to or less than γ (° C.), the constant C is determined according to the characteristic diagram of FIG. 7 so that the constant C linearly decreases as the outside air temperature increases.

When the constant C is determined as described above,
In step 307, it calculates a target rotational speed f _n on the basis of Equation 5 below.

[0038]

Equation 5] _{f n = f n-1 +} CΔf Next, actual speed rotational speed target rotation of the compressor 13 f _n
In step 308, the inverter 2
2 is energized. As described above, step 107
Is Yes, ie, the outside air temperature is β
(° C) or more, the compressor speed control is performed.

In this embodiment, when the outside air temperature is equal to or higher than β (° C.), that is, when the heating is under a low load, the increasing amount Δf of the rotation speed of the high-pressure fuzzy control compressor 13 is set to be smaller than that in the normal state, and the compression is performed. The rotation speed of the machine 13 is not suddenly increased. Then, when the heating is under a low load, the rotation speed of the compressor 13 overshoots the target rotation speed, thereby preventing the compressor 13 from stopping.

When the outside air temperature is smaller than β (° C.), the heating load is large, and the danger that the rotation speed of the compressor 13 will overshoot the target rotation speed is small.
The increase amount Δf of the rotation speed of the compressor 13 is increased.
As described above, in the present embodiment, since the rotation speed control of the compressor 13 is changed according to the heating load, it is possible to prevent the stop of the compressor 13 at the time of the low heating load, and at the same time, to reduce the heating high load. At times, the amount of change in the number of revolutions of the compressor 13 is increased, so that the temperature of the heating heat source can be quickly increased. (Second Embodiment) FIG. 8 is a flowchart according to a second embodiment of the present invention. In the second embodiment, the control processing routine for controlling the rotation speed of the compressor 13 by the control device 24 is different from that of the first embodiment, but the overall configuration is the same as that of the first embodiment.

In the first embodiment, whether or not heating is at a low load is determined based on the outside air temperature. However, in the second embodiment, the heating load is a deviation E between the actual high pressure SP detected by the target high pressure SPO and the pressure sensor 14 _n (= SP
O-SP). 8, steps 401 to 406 are the same as steps 101 to 106 of the first embodiment, and a description thereof will be omitted. In step 407, the target high-pressure SPO and the deviation E _n is a predetermined value i with the high pressure SP (e.g. i = 5 kg / cm
² G) It is determined whether or not it is greater than or equal to.

When the result of step 407 is Yes, that is, when the heating load is large, the process proceeds to step 408,
First high-pressure fuzzy control is performed. On the other hand, when the result of step 407 is No, that is, when the heating load is small, the process shifts to step 409 to perform the second high-pressure fuzzy control. The control processing routine of the first fuzzy control in step 408 is the same as that in step 108 of the first embodiment, that is, the subroutine shown in FIG. On the other hand, the control processing routine of the second fuzzy control of step 409 is as follows:
Only the method of determining the constant C in step 306 in FIG. 4 differs from the first embodiment.

FIG. 9 is a characteristic diagram for determining a constant C in the second high-pressure fuzzy control of the second embodiment. In the example of FIG. 9, the deviation E _n (= SPO-SP) is at greater than b (e.g. 10kg / cm ² G), the constant C is set to 1.0. On the other hand, the deviation E _n is a (e.g. 5k
g / cm ² G), the constant C is set to 0.5. Then, when the deviation E _n is 5 to 10, the constant C in accordance with the deviation E _n is increased to increase linearly, it is determined according to the characteristic diagram of FIG.

Also in the second embodiment, the target high pressure SPO
And to determine the heating load by deviations E _n the high pressure SP, but when the deviation E _n is small (when heating low load) than normal increasing amounts Δf of the rotational speed of the compressor 13 of the high-pressure fuzzy control The rotation speed of the compressor 13 is set to a small value so as not to rapidly increase. And at the time of heating low load,
This prevents the rotation speed of the compressor 13 from overshooting the target rotation speed, thereby preventing the compressor 13 from stopping.

Further, in the case a large difference E _n (the heating load), the rotational speed of the compressor 13 is small risk of overshooting the target rotational speed, the amount of increase in the rotational speed of the compressor 13 Δf is increased. in this way,
In the second embodiment, similarly to the first embodiment, since the rotation speed control of the compressor 13 is changed according to the heating load, it is possible to prevent the compressor 13 from stopping when the heating load is low. When the heating load is high, the amount of change in the number of revolutions of the compressor 13 is increased, thereby making it possible to accelerate the temperature rise of the heating heat source. (Third Embodiment) FIG. 10 is a flowchart according to a third embodiment of the present invention. In the third embodiment, the control processing routine of the rotation speed of the compressor 13 by the control device 24 is different from the first and second embodiments, but the overall configuration is the first embodiment.
And the same as in the second embodiment. In the third embodiment, similarly to the second embodiment, the target high pressure SPO and the high pressure SP
Load heating based on the deviation E _n and is determined.

In FIG. 10, steps 501 to 507 correspond to step 401 of FIG. 8 according to the second embodiment.
To 407, the description is omitted. In step 507, when the determination result is Yes, that is, when the heating load is large, the process proceeds to step 508, and the first blower level speed control is performed. On the other hand, when the result of step 507 is No, that is, when the heating load is small, the process shifts to step 509 to perform the second blower level speed control.

[0047] Figure 11 is a characteristic diagram for determining the blower level Deviation E _n. As shown in the characteristic diagram of FIG. 11, when the deviation En is _equal to or more than i (at the time of a high heating load), the deviation E
_{When n} is smaller than i (at the time of low heating load), the characteristic of the blower level with respect to the high pressure SP is changed. In other words, the rate of change of the blower level with respect to the high pressure SP is set to be higher at a low heating load than at a high heating load.

For example, in the characteristic diagram shown in FIG.
_{When n} is smaller than i (during a low heating load), the rate of change of the blower level is increased. At the time of heating low load, the rotation speed of the compressor 13 is in a state where it is easily increased rapidly,
When the heating load is low, the load on the compressor 13 is increased by increasing the rate of change of the blower level, thereby suppressing a rapid increase in the rotation speed. This prevents the rotation speed of the compressor 13 from overshooting the target rotation speed during a low heating load, and prevents the compressor 13 from stopping.

When the deviation En is greater than or _equal to i (high heating load), the rate of change of the blower level is reduced.
This suppresses the rapid blowing of cold air having a low temperature of the heating heat source at the time of a high heating load, thereby preventing the feeling from deteriorating. As described above, the change rate of the blower level with respect to the high pressure SP is not uniquely determined, but is changed according to the heating load.
It is possible to solve both the problem of the feeling and the worsening of the feeling when the heating load is high. Other Embodiments In the third embodiment, it is determined on the basis of the heating load on the deviation E _n of the target high SPO and high pressure SP. However, in the third embodiment, the characteristics of the blower level may be changed by determining the heating load based on the outside air temperature.

In order to prevent the compressor 13 from overshooting, the high pressure fuzzy control and the blower level control of the first to third embodiments may be combined. In this case, FIG. 5 in the first and second embodiments is used.
The control characteristic diagram of the cool air prevention control is changed to the characteristic diagram of FIG. 11 to perform the cool air prevention control, and thereafter, the high pressure fuzzy control is performed.

In the first to third embodiments, the system configuration of the air-heated heat pump is adopted. However, even with a water heating type heat pump as disclosed in Japanese Patent Application Laid-Open No. 9-220924, the same function and effect can be obtained. In a water heating type heat pump, the heating load is determined based on an outside air temperature or a deviation (TWO-TW) between the target hot water temperature TWO and the hot water temperature TW. Here, the temperature TW of the hot water is expressed as a function of the high pressure SP, and the deviation (TWO-TW) between the target hot water temperature TWO and the hot water temperature TW is also a function of the deviation (SPO-SP) between the target high pressure SPO and the high pressure SP. It is known to be represented as Therefore, even in a water-heated heat pump, the heating load is set to the deviation (S) between the target high pressure SPO and the high pressure SP.
PO-SP) can be determined based on the quantity related to (PO-SP).

It should be noted that the numerical values shown in the above-described embodiment are for showing one specific example, and are not for limiting the present invention.

[Brief description of the drawings]

FIG. 1 is an overall system diagram of a first embodiment of the present invention, showing a heating cycle.

FIG. 2 is a flowchart showing control contents of an ECU according to the first embodiment of the present invention.

FIG. 3 is a flowchart showing the contents of control of the compressor rotation speed at the time of a high heating load according to the first embodiment.

FIG. 4 is a flowchart illustrating the content of control of the compressor rotation speed at the time of a low heating load according to the first embodiment.

FIG. 5 is a characteristic diagram showing a relationship between a high pressure and a blower level in the cold air prevention control of the present invention.

FIGS. 6A and 6B are diagrams showing membership functions in the compressor speed control of the present invention.

FIG. 7 is a characteristic diagram for determining a constant C in compressor speed control of the first embodiment.

FIG. 8 is a flowchart showing control contents of an ECU according to a second embodiment of the present invention.

FIG. 9 is a characteristic diagram for determining a constant C in compressor speed control of the second embodiment.

FIG. 10 is a flowchart showing control contents of an ECU according to a third embodiment of the present invention.

FIG. 11 is a characteristic diagram for determining an air volume in blower level control according to a third embodiment.

[Explanation of symbols]

2: air conditioning duct, 8: evaporator, 9: condenser, 13: electric compressor, 18: outdoor heat exchanger, 19, 20: decompression means.

Claims (4)

[Claims] A blower (7) for generating an air flow; an air conditioning duct (2) for guiding air generated by the blower (7) into a room; a compressor (13) for compressing and discharging a refrigerant; A condenser (9) arranged in the air conditioning duct (2) for heating the conditioned air during heating; a decompression unit (19) for decompressing the refrigerant condensed in the condenser (9); An outdoor heat exchanger (18) for exchanging heat between outdoor air and a refrigerant; and during a heating cycle, the compressor (13) → the condenser (9) → the pressure reducing means (19) → the outdoor heat exchanger. (1
8) → In the air conditioner in which the outdoor heat exchanger (18) acts as an evaporator by the refrigerant flowing through the path of the compressor (13), and the condenser (9) heats the conditioned air, The air conditioner further includes load determining means (24, S107, S407, S507) for determining an air conditioning load at the time of the heating cycle, and a compressor speed control means (22) for controlling the speed of the compressor (13). The load determining means (24, S107, S407, S50)
According to 7), when it is determined that the air conditioning load during the heating cycle is low, the compressor rotation speed control means (22, 2, 2) is compared with when it is determined that the air conditioning load is high.
4) An air conditioner characterized by suppressing the increase speed of the rotation speed of the compressor (13). 2. A blower (7) for generating an air flow, an air conditioning duct (2) for guiding the air generated by the blower (7) into a room, a compressor (13) for compressing and discharging a refrigerant, A condenser (9) disposed in the air conditioning duct (2) for heating the conditioned air during heating; a decompression means (19) for decompressing the refrigerant condensed in the condenser (9); An outdoor heat exchanger (18) for exchanging heat between outdoor air and a refrigerant; and during a heating cycle, the compressor (13) → the condenser (9) → the pressure reducing means (19) → the outdoor heat exchanger. (1
8) → In the air conditioner in which the outdoor heat exchanger (18) acts as an evaporator by the refrigerant flowing through the path of the compressor (13), and the condenser (9) heats the conditioned air, The air conditioner further includes a load determining unit (24, S107, S407, S507) for determining an air-conditioning load at the time of the heating cycle, and a blowing amount control unit (24) for controlling a blowing amount of the blower (7). Means (24, S107, S407, S50
According to 7), when it is determined that the air-conditioning load during the heating cycle is low, compared to when it is determined that the air-conditioning load is high, the blower amount control means (24) controls the blower (7). An air conditioner characterized by increasing the rate of increase in air flow. 3. An air volume control means (24) for controlling an air volume of said air blower (7), wherein said load determination means (24, S107, S407, S50).
According to 7), when it is determined that the air conditioning load during the heating cycle is low, the compressor rotation speed control means (22, 2, 2) is compared with when it is determined that the air conditioning load is high.
4) The method according to claim 1, wherein 4) suppresses the speed of increasing the rotation speed of the compressor (13), and the air volume control means (24) increases the air volume increasing speed of the air blower (7). An air conditioner as described. 4. The load determining means (24, S107, S107)
407, S507) determines the air-conditioning load during the heating cycle based on at least one of the outside air temperature (β) and the amount related to the deviation (E _n ) between the target high pressure (SPO) and the high pressure (SP). The air conditioner according to any one of claims 1 to 3, wherein: