WO2007108066A1

WO2007108066A1 - Air conditioner for vehicle

Info

Publication number: WO2007108066A1
Application number: PCT/JP2006/305387
Authority: WO
Inventors: Shoji Isoda
Original assignee: Mitsubishi Denki Kabushiki Kaisha
Priority date: 2006-03-17
Filing date: 2006-03-17
Publication date: 2007-09-27
Also published as: JPWO2007108066A1

Abstract

An air conditioner for a vehicle, in which a variation in the temperature of discharge air is reduced when a temperature-controlled air is supplied into a cabin space. The air conditioner has a cooling device (5) capable of stepwise changing a cold energy quantity, heaters (6A, 6B, 6C) forming a heating device (6) that is capable of stepwise changing a heat production quantity and having different heat production capacities, and a controller (30) having a supply heat quantity calculation part (30A) for calculating the quantity of heat supply to the cabin space (2) and also having a heat production quantity/cold energy quantity setting part (30B) for setting, based on the quantity of heat supply calculated in the supply heat quantity calculation part (30A), the quantity of heat production by both the cooling device (5) and the heating device (6).

Description

Specification

Vehicle air conditioner

Technical field

[0001] The present invention relates to an air conditioner, and more particularly to an air conditioner for a vehicle.

Background art

[0002] Vehicle air conditioners using a refrigeration cycle are already known (see, for example, Patent Document 1 and Patent Document 2). In addition, in recent years, automatic control has been carried out to automatically adjust the air conditioning capacity so that the in-vehicle temperature matches the target temperature. The control device (temperature controller) continuously requires the required air conditioning capacity based on the deviation between the target temperature and the in-vehicle temperature, but the compressor used in the cooling device has been confirmed to be safe due to problems such as resonance in the piping system. Since only stepped operation can be performed only at the specified frequency, the air conditioning capacity (cooling capacity) can only be changed in stages. Furthermore, since lubrication of the rotating parts and sliding parts of refrigeration equipment requires stable circulation of the lubricating oil mixed in the refrigerant circuit, operation at low frequencies (for example, less than 30 Hz) may not be possible. Yes, it is difficult to cope with minute cooling loads. In the case where there are restrictions on the air conditioner hardware as described above, in order to generate the required air conditioning capacity approximately, the conventional method is to use both compressor stage operation and heater energization rate control (energization time control). Is adopted. Since the heating rate control of the heater can control the calorific value in a stepless manner on a time average, the calorific value is controlled macroscopically.

Patent Document 1: Japanese Patent Laid-Open No. 5-139142

Patent Document 2: Japanese Patent Laid-Open No. 2004-182201

Disclosure of the invention

Problems to be solved by the invention

[0003] As described above, in the conventional vehicle air conditioner, the necessary air conditioning capacity is approximately generated by using the compressor stage operation and the heater energization rate control together. There was a problem that the temperature inside the car fluctuated due to fluctuations in the temperature of the blown air caused by repeated conduction. In addition, there was another problem when discomfort was given to passengers near the outlet due to temperature fluctuations (temperature ripple) of the outlet. [0004] The present invention has been made to solve the above-described problems. When supplying temperature-adjusted air into a vehicle, the vehicle can reduce fluctuations in the temperature of the blown-out air more than a conventional device. The purpose is to propose an air conditioner.

Means for solving the problem

[0005] The vehicle air conditioner according to the present invention calculates the amount of heat supplied to the vehicle based on input information, a cooling device that can change the amount of cooling in stages, a heating device that can change the amount of heat generation in steps. And a control device that sets the amount of heat generated by the cooling device and the heating device based on the calculated supply heat amount.

Normally, the apparatus further includes target temperature setting means for setting a target value of the in-vehicle temperature, and in-vehicle temperature detection means for detecting the in-vehicle temperature, and the control device sets the set value of the target temperature setting means and the set value of the target temperature. The amount of heat supplied to the vehicle is calculated based on the input information with the detection value of the vehicle interior temperature detection means.

The invention's effect

[0006] Since the vehicle air conditioner according to the present invention determines the air conditioning capacity by combining a cooling device that can change the amount of heat in stages and a heating device that can change the amount of heat generation in steps. While suppressing the instantaneous fluctuation of the blown air temperature, the optimum amount of heat (cooling heat and heat generation) is always supplied into the vehicle, and the instantaneous fluctuation of the vehicle temperature can be suppressed. In addition, fine adjustment of the air-conditioning capacity is possible if the stepwise changes in cooling and heating equipment are set in detail.

Furthermore, since the vehicle air conditioner of the present invention can supply the optimal amount of heat into the vehicle without controlling the heater energization rate, the frequency of opening and closing (ON / OFF) of the heater drive switch is greatly reduced. The product life of the switch can be improved.

Brief Description of Drawings

FIG. 1 is an explanatory diagram showing an example of application of a vehicle air conditioner according to an embodiment of the present invention to a vehicle.

FIG. 2 is a configuration diagram of a refrigeration cycle of a cooling device that constitutes the vehicle air conditioner of FIG.

FIG. 3 is a block diagram showing the configuration of the vehicle air conditioner according to the embodiment of the present invention.

4 is a flowchart showing the control contents of a control device constituting the vehicle air conditioner of FIG.

FIG. 5 is a timing chart showing an example of the operation of the vehicle air conditioner of FIG. BEST MODE FOR CARRYING OUT THE INVENTION

FIG. 1 is a configuration diagram of a vehicle air conditioner in an embodiment of the present invention. In FIG. 1, a vehicle 1 in which an air conditioner 20 is installed is composed of an interior space (also simply referred to as an interior) 2, an underfloor space 3, and a rooftop space 4. In addition, in FIG. 1, the force air conditioner 20 which describes the case where the air conditioner 20 is installed in the underfloor space 3 may be installed in the roof space 4. The air conditioner 20 includes a cooling device 5 that can change the amount of cooling in stages, a heating device 6 that can change the amount of heat generated in steps, an indoor fan 7, and an outdoor fan 8.

Reference numeral 9 in FIG. 1 denotes a return duct for returning air from the vehicle interior space 2 to the air conditioner 20, and reference numeral 10 denotes an outlet duct for sending air from the air conditioner 20 to the vehicle interior space 2.

FIG. 2 is a configuration diagram of the cooling device 5. The cooling device 5 includes a refrigeration cycle having a refrigerant circuit force in which an evaporator 21, a compressor 22, a condenser 23, and an expansion valve 24 are sequentially connected by piping. Have been. Further, the vehicle interior space 2 is provided with a temperature sensor 11 as vehicle interior temperature detection means.

Next, the air conditioning operation of the air conditioner 20 in the vehicle 1 will be described. The interior air in the interior space 2 is driven by the indoor fan 7 and taken into the air conditioner 20 via the return duct 9. Then, it is cooled by the evaporator 21 inside the air conditioner 20, and further heated by the heater 6 if necessary, and supplied to the vehicle interior space 2 via the blowout duct 10. On the other hand, when the outside air driven by the outdoor fan 8 passes through the condenser 23, the refrigerant in the refrigeration cycle is cooled.

FIG. 3 is a block diagram showing a configuration of the air conditioner 20 and its accessory devices. As described above, the air conditioner 20 has a difference in heat generation capability as a heating element that forms a cooling device 5 that can change the amount of heat in stages and a heating device that can change the amount of heat in steps. It has multiple heaters 6A, 6B and 6C.

The cooling capacity of the cooling device 5 can be changed by controlling the operation frequency of the compressor 22 constituting the cooling device 5 by the inverter 32. Here, the operating frequency of the cooling device 5 is assumed to use only three stages of 40/50 / 60HZ due to the vibration surface of the refrigerant circuit and the restriction of the circulation of the lubricating oil, and each cooling capacity is -5 / -7 / -9kW. The compressor 22 The operating frequency is not necessarily limited to these three stages and values, but may be changed as appropriate within a range where safety is ensured.

[0013] On the other hand, the heating device 6 is composed of three types of heaters 6A, 6B, and 6C each having a different heating capacity as a heating element, and each of the heaters 6A, 6B, and 6C Energization is controlled by the corresponding switches 31A, 31B, 31C. Here, the heat generation capacities of heaters 6A, 6B, and 6C are l / 2 / 4kW, respectively, and the total heat generation capacity is 7kW.

Note that the number of heaters constituting the heating device 6 and the heat generation capacity are not limited to the above example, and the air conditioning temperature can be set more finely according to the stepwise change in the amount of cooling of the cooling device 5. It can be the number or ability. A heating element other than the heater can also be used.

[0014] In this example, the heating capacity can be set at equal intervals between the heating capacity by the operation of one heater having the minimum heat generation capacity and the heating capacity by the operation of all the heaters. In addition, a heater having a heat generation capacity capable of setting the cooling capacity at equal intervals between the stop of the compressor 22 and the operation at the maximum operating frequency is selected and installed (see Table 2 described later).

[0015] The air conditioner 20 further includes a supply heat amount calculation unit 30A that calculates the amount of heat supplied to the vehicle interior space 2, and the cooling device 5 and the heaters 6A, 6B, based on the supply heat amount calculated by the supply heat amount calculation unit 30A. A control device 30 having a calorific value Z cold energy setting unit 30B for setting a heat generation amount of 6C is provided.

The supplied heat amount calculation unit 30A calculates the supplied heat amount necessary to set the vehicle interior space 2 to the target temperature based on the target value and the actual temperature of the vehicle interior space 2. This can be done, for example, by proportional integral (PI) calculations. In the proportional integral (PI) calculation, the air conditioning capacity command value (or supply) is calculated from the sum of the deviation between the target temperature and the temperature in the interior space 2 multiplied by the proportional gain, and the deviation integrated over time to obtain the integral gain. (Heat command value) Q is calculated.

Calorific value Z Cold energy setting unit 30B sets the operation of cooling device 5 and heaters 6A, 6B, 6C so that the supply heat amount calculated by supply heat amount calculation unit 30A can be obtained, and switch 31A , 31B, 31C and inverter 32 are controlled. Therefore, the control device 30 performs the above calculation and A force such as a microcomputer with pre-programmed control functions is also configured.

Note that, as shown in FIG. 3, here, the operation panel 12 serves as target temperature setting means for setting a target value, and the temperature sensor 11 serves as vehicle temperature detection means for detecting the temperature of the vehicle interior space 2, respectively. The setting data and the detection data are taken into the control device 30 as input information.

[0018] Table 1 shows the air conditioning capability of the air conditioner 20 configured as described above.

[table 1]

FIG. 4 is a flowchart showing the control contents of the control device 30. The operation of the control device 30 will be described with reference to FIG.

(Step S1) The target temperature of the vehicle interior space 2 set by the operation panel 12 and the current value of the vehicle interior temperature 2 detected by the temperature sensor 11 are input to the control device 30 of the air conditioner 20. (Step S2) In the control device 30, based on the value taken in in S1, the supply heat amount calculation unit 30A calculates the supply heat amount necessary for setting the interior space 2 to the target temperature. For example, proportional-integral (PI) calculation is performed based on the deviation between the target temperature and the actual in-vehicle temperature, and the air conditioning capability command value Q corresponding to the supplied heat amount is calculated. The air conditioning capability command value Q can be substituted by proportional integral derivative (PID) calculation.

(Step S3) Based on the air conditioning capability command value Q, the control device 30 determines the operation pattern previously determined and stored by the combination of the operation frequency of the cooling device 5 and the heaters 6A, 6B, 6C to be energized. To select the corresponding operation pattern. Operating capacity for air conditioning capability command value Q For example, the turn is determined as shown in Table 2.

(Steps S4, S5) The control device 30 controls the operation of the cooling device 5 and the heaters 6A, 6B, 6C by controlling the inverter 32 and the circuit breakers 31A, 31B, 31C according to the selected operation pattern. The air conditioning capacity of the air conditioner 20 is automatically adjusted.

[Table 2]

[0021] In this air conditioner 20, by setting the heat generation capacities of the heaters 6A, 6B, and 6C to l / 2 / 4kW, the air conditioning capacity in lkW increments can be selected. On the other hand, in order to satisfy the total heating value of heaters 6A, 6B, and 6C of 7 kW, for example, the heating device 6 is composed of three types of heaters having a heat generation capacity of 7 kW ÷ 3 = 2.3 kW, for example. In this case, since the minimum setting increment of air conditioning capacity is 2.3kW, the resolution (in steps) of air conditioning capacity is worse than the combination shown in Table 2. In this case, there is no need to limit the number of force heaters, which is a specific example of a configuration with three heaters.

FIG. 5 is a timing chart showing the timing operation of the relevant part when the air conditioning capability command value Q shifts from −4 kW to −3 kW in the air conditioner 20 configured as described above. When air conditioning capability command value Q is -4kW, -3> Q≥-4, so "1" in Table 2 is selected as the operation pattern. Next, when the air conditioning capacity command value Q increases to -3kW, -2> Q≥-3, so "k" in Table 2 is selected as the operation pattern.

[0023] As described above, in this air conditioner 20, the heating value of the heater is set so that the cooling capacity and the heating capacity can be combined to reduce the resolution (step) of the obtained air conditioning capacity. Selected. This makes it possible to always supply a stable amount of heat to the vehicle interior space 2 according to the air conditioning capability command value Q by simple heater ON / OFF control. In other words, the optimal amount of heat (cold heat and heat generation) can be supplied to the vehicle at all times while suppressing fluctuations in the temperature of the blown air, so the temperature of the interior space 2 can be controlled stably with little fluctuation. It will be.

[0024] In addition, according to the air conditioner 20 according to this embodiment, the air-conditioning capacity can be controlled in a fine manner without performing the conventional energization rate control (energization time control). / The frequency of OFF can be greatly reduced and the product life of the switch can be improved.

Although the effect of fluctuations in the temperature of the blown air on the temperature inside the vehicle varies depending on vehicle body characteristics (such as the heat capacity and heat dissipation characteristics of the vehicle body), the vehicle air conditioner of the present invention has a narrow interior space such as the air conditioning of the driver's seat. Small heat capacity! / Suitable for air conditioning in some cases.

Explanation of symbols

[0025] 1 vehicle, 2 interior space, 3 floor space, 4 roof space, 5 cooling system, 6 heating system, 6A, 6B, 6C heater, 7 indoor fan, 8 outdoor fan, 9 return duct, 10 outlet duct, 11 Temperature sensor, 12 Control panel, 20 Air conditioner, 21 Evaporator, 22 Compressor, 23 Condenser, 24 Expansion valve, 30 Control device, 30A Supply heat amount calculation unit, 30B Heat generation amount Z Cold energy setting unit, 31A, 31B , 31C switch, 32 inverter.

Claims

The scope of the claims

[1] a cooling device capable of changing the amount of cooling in stages;

A heating device capable of changing the calorific value in stages;

A controller that calculates the amount of heat supplied to the vehicle based on the input information, and sets the amount of heat generated by the cooling device and the heating device based on the calculated amount of supplied heat;

A vehicle air conditioner comprising:

[2] Target temperature setting means for setting the target value of the vehicle interior temperature,

An in-vehicle temperature detecting means for detecting the in-vehicle temperature,

2. The vehicle air conditioner according to claim 1, wherein the control device calculates an amount of heat supplied into the vehicle based on input information of a set value of the target temperature setting unit and a detection value of the in-vehicle temperature detection unit. apparatus.

[3] The cooling device is a refrigeration cycle device having a compressor capable of switching the operating frequency to a plurality of stages, and the amount of cooling heat can be changed stepwise by switching the operating frequency of the compressor. The vehicle air conditioner according to claim 1 or 2, characterized in that

[4] The heating device includes a plurality of heating elements having different heat generation capacities, and the amount of generated heat can be changed stepwise by a combination of operations of the heating elements. The vehicle air conditioner according to any one of the above.

[5] The plurality of heating elements have a heating capacity set at equal intervals between the heating capacity by the operation of one heating element having the minimum heating capacity and the heating capacity by the operation of all the heating elements. The heat generation capability is such that the cooling capability can be set at equal intervals between the stop of the compressor and the operation at the maximum operating frequency. 4. The vehicle air conditioner according to 4.

[6] The control device has a predetermined operation pattern based on a combination of an operation frequency of the compressor and the heating element for each predetermined amount of heat supplied, and the cooling device and the heating device based on the operation pattern 6. The vehicle air conditioner according to claim 4, wherein the vehicle air conditioner is controlled.