JP3791234B2 - Air conditioner for hybrid vehicles. - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an air conditioner for a hybrid vehicle equipped with a traveling engine and a traveling motor.
[0002]
[Prior art]
As a conventional hybrid vehicle air conditioner, there is one described in Japanese Patent Laid-Open No. 9-76740. The device described in this publication supplies electric power from a common battery to an electric compressor that compresses refrigerant and a traveling motor. When the battery charge remaining below the threshold value (target value) while the vehicle is stopped, the power used by the air conditioner is limited and the traveling motor (motor generator) is driven by the traveling engine. To generate electricity and charge the battery.
[0003]
[Problems to be solved by the invention]
However, in the conventional apparatus, the power consumption of the air conditioner is only limited when the battery needs to be charged as described above. When the load is heavy, the remaining battery charge drops to the threshold value in a short time, making it easier for the engine to operate intermittently for charging while the vehicle is stopped, reducing the amount of environmentally hazardous substances emitted, which is an advantage of hybrid vehicles This is a major negative factor for realizing high fuel efficiency.
[0004]
In view of the above, the present invention has an object to increase the amount of charge during traveling and to enable long-term use of an air conditioner without charging even after stopping.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, according to the first to seventh aspects of the present invention, when the remaining charge of the battery (4) for supplying electric power to the traveling motor (2) becomes equal to or less than a target value, the traveling engine (1) is provided. Mounted on a hybrid vehicle that charges the battery (4) from the generator (2) driven by
An air conditioner unit (6) which is supplied with electric power from the battery (4) and air-conditions the vehicle interior;
Calculate the air conditioning required power required by the air conditioner unit (6) to adjust the temperature in the passenger compartment to the arbitrarily set temperature,
During traveling of the vehicle, the target value is set higher as the required air conditioning power increases.
[0006]
According to this, since the charge amount of the battery (4) can be increased during traveling, the air conditioner can be used for a long time without being charged even after stopping. Therefore, the time from when the vehicle is stopped until the engine (1) is started for charging (the engine stop time when the vehicle is stopped) becomes longer, and the operation of the stopped engine (1) is reduced as much as possible. Emissions can be reduced and fuel consumption can be improved.
[0007]
The invention according to claim 2 is characterized in that the power consumption of the air conditioner unit (6) is limited to a predetermined value smaller than the air conditioning required power as the remaining charge of the battery (4) decreases.
According to this, when the remaining charge of the battery (4) is low, the load on the battery (4) can be reduced, and the engine stop time while the vehicle is stopped can be further extended. Improvement is possible.
[0008]
The invention according to claim 3 is characterized in that the electric power used by the air conditioner unit (6) is limited to a predetermined value smaller than the electric power required for air conditioning while the vehicle is stopped.
According to this, the load on the stopped battery (4) can be reduced, the engine stop time can be further extended while the vehicle is stopped, and the amount of environmentally destructive substances discharged can be reduced and fuel consumption can be improved.
[0009]
The invention according to claim 4 is characterized in that the target value is set lower when the vehicle is stopped than when the vehicle is traveling. This also makes it possible to extend the engine stop time while the vehicle is stopped, thereby reducing the amount of environmentally destructive substances discharged and improving fuel consumption.
As in the fifth aspect of the present invention, the restriction on the power consumption of the air conditioner unit (6) is prohibited when the air conditioning heat load is large or the defroster mode is in which air is blown to the vehicle window glass. Therefore, priority can be given to comfort and safety (securing visibility).
[0010]
In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1-7 shows one Embodiment of this invention, The whole structure of a hybrid vehicle and an air conditioner is demonstrated based on FIG.
The hybrid vehicle includes a traveling engine 1 that uses gasoline as fuel, a traveling motor 2 that includes a motor and a motor generator that functions as a generator, an engine control device that controls the amount of fuel supplied to the engine 1, the ignition timing, and the like. 3, a battery (for example, a nickel metal hydride storage battery) 4 for supplying electric power to the motor 2, the engine control device 3 and the like, controls the motor 2 (for example, inverter control), and sends a control signal (the number of revolutions of the engine 1) to the engine control device 3 And a target value of torque, etc.) are provided.
[0012]
Based on a control signal from the vehicle control device 5, the engine control device 3 controls the fuel supply amount, ignition timing, etc. so that the engine speed and torque of the engine 1 become target values and high combustion efficiency is obtained. Optimum control.
The vehicle control device 5 basically performs the following control. First, when the operation of the engine 1 is necessary, the motor 2 is driven to start the engine 1. In addition, in order to obtain the driving force of the hybrid vehicle, the operation, stop, and rotation speed of the motor 2 are controlled, and the rotation speed and target torque value of the engine 1 are output to the engine control device 3. Only the power of the motor 2 is transmitted to the drive wheels of the hybrid vehicle when starting and traveling at a low speed, only the power of the engine 1 is transmitted during normal traveling at a predetermined speed or higher, and the engine is accelerated when accelerating at a predetermined speed or higher. Power is transmitted from both 1 and the motor 2.
[0013]
Further, the vehicle control device 5 operates the engine 1 to drive the motor 2 when the battery 4 needs to be charged, and operates the motor 2 as a generator. Further, a signal is output to the engine control device 3 so that the engine 1 is stopped when the vehicle speed is a predetermined speed (for example, 50 km / h) or less and the accelerator pedal is OFF (the pedal depression amount is 0). .
[0014]
The air conditioner includes an air conditioner unit 6 that air-conditions the vehicle interior and an air conditioner control device 7 that controls devices constituting the air conditioner unit 6. In this example, the temperature in the vehicle interior is automatically controlled to an arbitrarily set temperature. It is an auto air conditioner.
The air conditioner unit 6 is disposed on the front side of the vehicle interior, and forms an air passage that guides conditioned air into the vehicle interior. The centrifugal blower 30 that sends air in the air conditioning duct 10 and the air conditioning duct 10 The refrigeration cycle 40 that cools the air flowing through the air conditioning duct 10, the cooling water circuit 50 that heats the air flowing through the air conditioning duct 10, and the like.
[0015]
The inside / outside air switching box provided on the most upstream side of the air flow of the air conditioning duct 10 has an inside air suction port 11 and an outside air suction port 12, and these suction ports 11, 12 are opened and closed by an inside / outside air switching damper 13. The inside / outside air switching damper 13 is driven by an actuator 14 such as a servo motor.
A defroster opening, a face opening, and a foot opening are formed on the most downstream side of the air flow of the air conditioning duct 10. A defroster duct 15 is connected to the defroster opening, and a defroster outlet 18 for blowing conditioned air toward the inner surface of the windshield of the vehicle is opened at the most downstream end of the defroster duct 15.
[0016]
In addition, a face duct 16 is connected to the face opening, and a face air outlet 19 that blows out conditioned air toward the upper half of the occupant is opened at the most downstream end of the face duct 16. Further, a foot duct 17 is connected to the foot opening, and a foot air outlet 20 that blows out conditioned air toward the feet of the occupant is opened at the most downstream end of the foot duct 17.
[0017]
And two blower outlet switching dampers 21 are rotatably attached to the inside of each blower outlet. These blower outlet switching dampers 21 are each driven by an actuator 22 such as a servo motor to switch the blower outlet mode to any one of a face mode, a bi-level mode, a foot mode, a foot differential mode, and a defroster mode.
[0018]
The blower 30 includes a centrifugal fan 31 that is rotatably housed in a scroll case that is integrally formed with the air conditioning duct 10, and a blower motor 32 that rotationally drives the centrifugal fan 31. The blower motor 32 controls the air flow rate (the rotational speed of the centrifugal fan 31) based on the blower terminal voltage applied via the blower drive circuit 33.
[0019]
The refrigeration cycle 40 condenses and liquefies refrigerant by exchanging heat between the compressed refrigerant and outside air, and an electric compressor 41 including a compression mechanism that compresses the refrigerant and a motor that receives power from the battery 4 and drives the compression mechanism. Condenser 42, a gas-liquid separator 43 that gas-liquid separates the condensed and liquefied refrigerant and flows only the liquid refrigerant downstream, an expansion valve 44 that decompresses and expands the liquid refrigerant, and exchanges heat between the decompressed and expanded refrigerant and the conditioned air The cooling unit 46 includes an evaporator 45 that cools the conditioned air, a cooling fan 46 that blows outside air to the condenser 42, and a refrigerant pipe that connects them.
[0020]
An AC voltage is applied to the motor of the electric compressor 41 via the inverter 47, and the inverter 47 adjusts the frequency of the AC voltage based on a command from the air conditioner control device 7, thereby continuously adjusting the rotational speed of the electric compressor 41. To change.
The cooling water circuit 50 includes a heater core 51 disposed in a circuit that circulates the cooling water (hot water) of the engine 1 by a water pump (not shown). The heater core 51 exchanges heat between the engine cooling water and the conditioned air. Heat.
[0021]
The heater core 51 is disposed downstream of the evaporator 45 in the air conditioning duct 10 so as to partially block the air passage. An air mix damper 52 is rotatably mounted on the upstream side of the heater core 51, and the air mix damper 52 is driven by an actuator 53 such as a servo motor to bypass the warm air passing through the heater core 51 and the heater core 51. Adjust the temperature of the air blown into the passenger compartment by adjusting the ratio with the cold air.
[0022]
Next, the configuration of the control system will be described based on FIG. 1, FIG. 3, and FIG. The air conditioner control device 7 receives a communication signal output from the vehicle control device 5, a switch signal from each switch on the control panel 60 provided in the front of the vehicle interior, and a sensor signal from each sensor.
Here, each switch on the control panel 60 includes, as shown in FIG. 4, an air conditioner switch 61 for instructing start and stop of the refrigeration cycle 40 (electric compressor 41), and an intake for switching the inlet mode. A mouth changeover switch 62, a temperature setting lever 63 for setting the temperature in the passenger compartment to a desired temperature, an air volume switching lever 64 for switching the air flow rate of the centrifugal fan 31, and an air outlet switching for switching the air outlet mode. Such as a switch.
[0023]
The air outlet changeover switch includes a face switch 65 for fixing to the face mode, a bilevel switch 66 for fixing to the bilevel mode, a foot switch 67 for fixing to the foot mode, and a foot differential mode. There are a foot differential switch 68 for performing the operation and a defroster switch 69 for fixing the defroster mode.
[0024]
Further, as shown in FIG. 3, each sensor includes an internal air temperature sensor 71 that detects the air temperature inside the vehicle interior, an external air temperature sensor 72 that detects the air temperature outside the vehicle interior, and the amount of solar radiation irradiated to the vehicle interior. The solar radiation sensor 73, the evaporator air temperature sensor 74 for detecting the temperature of the air flowing into the evaporator 45 (evaporator intake air temperature TIN), and the air temperature immediately after passing through the evaporator 45 (evaporator air temperature) There are an evaporator blown air temperature sensor 75 for detecting the temperature, a water temperature sensor 76 for detecting the temperature of the cooling water flowing into the heater core 51, a vehicle speed sensor 77 for detecting the traveling speed of the vehicle, and the like.
[0025]
Among these, the thermistor is used for the inside air temperature sensor 71, the outside air temperature sensor 72, the evaporator intake air temperature sensor 74, the evaporator blown air temperature sensor 75, and the water temperature sensor 76.
Inside the air conditioner control device 7, a microcomputer comprising a CPU, ROM, RAM, etc. (not shown) is provided, and sensor signals from the sensors 71 to 77 are A / D by an input circuit (not shown) in the air conditioner control device 7. It is configured to be input to the microcomputer after being converted. The air conditioner control device 7 operates by being supplied with DC power from the battery 4 when the ignition switch of the vehicle is turned on.
[0026]
Next, control processing of the air conditioner control device 7 will be described based on FIGS. Here, FIG. 5 is a flowchart showing basic control processing by the air conditioner control device 7.
First, when the ignition switch is turned on and DC power is supplied to the air conditioner control device 7, the routine of FIG. 5 is started to perform each initialization and initial setting (step S1). Subsequently, a switch signal is read from each switch such as the temperature setting lever 63 (step S2). Subsequently, the sensor signals from the inside air temperature sensor 71, the outside air temperature sensor 72, the solar radiation sensor 73, the evaporator intake air temperature sensor 74, the evaporator blown air temperature sensor 75, the water temperature sensor 76, and the vehicle speed sensor 77 are A / D converted. The read signal is read (step S3).
[0027]
Subsequently, a target blowing temperature TAO of air blown into the passenger compartment is calculated based on the following equation 1 stored in advance in the ROM (step S4).
[0028]
[Expression 1]
TAO = Kset × Tset−KR × TR-KAM × TAM-KS × TS + C
Here, Tset is the set temperature set by the temperature setting lever 63, TR is the inside air temperature detected by the inside air temperature sensor 71, TAM is the outside air temperature detected by the outside air temperature sensor 72, and TS is detected by the solar radiation sensor 73. The amount of solar radiation. Kset, KR, KAM, and KS are gains, and C is a correction constant.
[0029]
Subsequently, a blower voltage (voltage applied to the blower motor 32) corresponding to the target blowing temperature TAO is determined from a characteristic diagram stored in advance in the ROM (step S5). Specifically, the lower the target blowing temperature TAO, the higher the blower voltage (the larger the air volume), and the lower the target blowing temperature TAO, the lower the blower voltage.
Subsequently, the suction port mode corresponding to the target outlet temperature TAO is determined from the characteristic diagram stored in advance in the ROM (step S6). Specifically, the inside air circulation mode is selected when the target blowing temperature TAO is low, and the outside air introduction mode is selected when the target blowing temperature TAO is high.
[0030]
Subsequently, the air outlet mode corresponding to the target air temperature TAO is determined from the characteristic chart stored in advance in the ROM (step S7). Specifically, the foot mode is selected when the target blowing temperature TAO is low, and the bi-level mode is selected in order of the face mode as the target blowing temperature TAO increases.
Subsequently, the opening degree of the air mix damper 52 is determined according to the target blowing temperature TAO, the evaporator blowing air temperature detected by the evaporator blowing air temperature sensor 75, the cooling water temperature detected by the water temperature sensor 76, and the like (step 8). ).
[0031]
Subsequently, in step S9, the subroutine shown in FIG. 6 is called to determine the rotational speed of the electric compressor 41 when the air conditioner switch 61 is ON.
Subsequently, control signals are output to the actuators 14, 22, 53, the blower drive circuit 33, and the inverter 47 so that the control states calculated or determined in steps 4 to 9 are obtained (step S10).
[0032]
Next, the control process for determining the rotational speed of the electric compressor will be described with reference to FIG. First, the target evaporator blowing air temperature TEO corresponding to the target blowing temperature TAO is calculated (step S91).
Further, in order to lower the air at the evaporator intake air temperature TIN to the target evaporator blowout air temperature TEO from a constant K determined by the target evaporator blowout air temperature TEO, the evaporator intake air temperature TIN, and the blown amount of the blower 30. The power that the air conditioner unit 6 originally needs (air conditioning required power) is calculated (step S92). Here, the higher the number of revolutions of the electric compressor 41, the higher the cooling performance of the refrigeration cycle 40. Therefore, the required air conditioning power is the difference between the evaporator intake air temperature TIN and the target evaporator outlet air temperature TEO. Increases as it grows.
[0033]
Next, the required air conditioning power calculated in step S92 is output to the vehicle control device 5 (step S93). Subsequently, the air conditioning usable power (details will be described later) calculated by the vehicle control device 5 is input (step S94).
Subsequently, in step 95, it is determined whether the heating or cooling operation with a large air conditioning heat load is immediately after starting (during warm-up or cool-down) or in the defroster mode. If the decision result in the step 95 is YES, the process advances to a step 97 to set the required air conditioning power as the use set power. And based on this use setting electric power, the rotation speed of the electric compressor 41 is determined (step S98).
[0034]
On the other hand, if the decision result in the step 95 is NO, the process advances to a step 96 to set the air conditioning usable power as the use set power. And based on this use setting electric power, the rotation speed of the electric compressor 41 is determined (step S98).
Next, a control process related to the air conditioner control in the vehicle control device 5 will be described with reference to FIG. Inside the vehicle control device 5 is provided a microcomputer comprising a CPU, ROM, RAM, etc. (not shown), and a sensor signal from the vehicle speed sensor 77 is A / D converted by an input circuit (not shown) in the vehicle control device 5. After that, it is configured to be input to the microcomputer. The vehicle control device 5 operates by being supplied with DC power from the battery 4 when the ignition switch of the vehicle is turned on.
[0035]
First, when the ignition switch is turned on and DC power is supplied to the vehicle control device 5, the routine of FIG. 7 is started, and each initialization and initial setting are performed (step S800).
Subsequently, the running speed of the vehicle is calculated based on the signal from the vehicle speed sensor 77, the state of charge of the battery 4 (remaining battery charge) is calculated based on the voltage of the battery 4, and further calculated by the air conditioner control device 7. The required air conditioning power is input (step 801).
[0036]
Subsequently, a charge state target value (threshold value) is calculated based on the required air conditioning power and the running state of the vehicle (step 802). While the vehicle is stopped, the charge state target value is kept constant at 30% regardless of the air conditioning required power as shown by the line a, and during driving, the charge state target value is set as the air conditioning required power increases as shown by the line b. Gradually increase from 50% to 80%. When the state of charge, that is, the remaining battery charge falls below the charge state target value, the driving motor 2 is driven by the engine 1 to cause the driving motor 2 to generate power, and the battery 4 is charged. .
[0037]
Basically, the engine 1 is stopped when the vehicle speed is a predetermined speed (for example, 50 km / h) or less and the accelerator pedal is OFF (the pedal depression amount is 0), but the charging state target value is not reached. Continues charging without stopping the engine 1 even under the above conditions.
Subsequently, a constant K is obtained according to the state of charge and the running state of the vehicle, and the constant K is multiplied by the required air conditioning power to calculate the air conditioning usable power (step 803). The constant K during travel is indicated by the line d, 0 when the state of charge, that is, the remaining battery charge is 10% or less, 0.5 between 10% and 20%, and remaining battery charge between 20% and 50%. It gradually increases as the amount increases, and becomes 1 at 50% or more. On the other hand, the constant K during stopping is 0.2 smaller than the constant K during traveling in the region where the remaining battery charge is 10% or more, as indicated by the line c.
[0038]
Next, the air conditioning usable power calculated in step S803 is output to the air conditioner control device 7 (step S804).
Subsequently, a control signal is output to the engine control device 3 so as to achieve the charge state target value calculated in Step 802 (Step S805).
Next, the operation of the air conditioner configured as described above will be briefly described. The air flowing in the duct 10 by the blower 30 is cooled by exchanging heat with the refrigerant when passing through the evaporator 45 in the refrigeration cycle 40. Here, by controlling the rotation speed of the electric compressor 41 by the air conditioner control device 7, the flow rate of the refrigerant flowing in the refrigeration cycle 40 is controlled to adjust the cooling performance of the refrigeration cycle 40.
[0039]
The air cooled by the evaporator 45 is heated by exchanging heat with the engine coolant when passing through the heater core 51 in the coolant circuit 50. The ratio of the air passing through the heater core 51 and the air bypassing the heater core 51 is adjusted according to the opening position of the air mix damper 52, and thus the conditioned air adjusted to a predetermined temperature is supplied to each of the outlets 18 to 20. Blow out from one or two of them.
[0040]
Hereinafter, features of the present embodiment will be described.
The power required for the air conditioner unit 6 to adjust the temperature in the passenger compartment to an arbitrarily set temperature (calculated power for air conditioning) is calculated, and the battery 4 increases as the required power for air conditioning increases while the vehicle is running. The charging state target value (charging start threshold value) is set high (step S802). According to this, the battery 4 can be charged while traveling, and the amount of charge can be increased by an amount corresponding to the power used by the air conditioner unit 6 at that time. Can be used. Accordingly, the time from when the vehicle is stopped until the engine 1 is started for charging (the engine stop time when the vehicle is stopped) becomes longer, and the operation of the engine 1 when the vehicle is stopped is reduced as much as possible, thereby reducing the amount of environmentally harmful substances discharged. And fuel economy can be improved.
[0041]
Further, by limiting the power used by the air conditioner unit 6 to less than the required air conditioning power as the remaining charge of the battery 4 decreases (steps S803 and S96), the load on the battery 4 when the remaining charge of the battery 4 decreases The engine stop time while the vehicle is stopped can be further extended.
Further, while the vehicle is stopped, the power consumption of the air conditioner unit 6 is limited to less than the required air conditioning power (steps S803 and S96), thereby reducing the load on the stopped battery 4 and further increasing the engine stop time while the vehicle is stopped. Can be long.
[0042]
Moreover, the engine stop time while the vehicle is stopped can be further increased by setting the charging state target value while the vehicle is stopped to be lower than when the vehicle is traveling (step S802).
Furthermore, when the air-conditioning heat load is large or in the defroster mode, it is possible to prioritize comfort and safety (securing visibility) by prohibiting the restriction of the power consumption of the air-conditioner unit 6 (steps S95 and S97).
(Other embodiments)
In addition, when sufficient heating capability cannot be obtained only with the cooling water of the engine 1, an electric heater (for example, a PTC heater) may be provided as a heating source of the conditioned air. In this case, the required air conditioning power is calculated including the power consumption of the electric heater.
[0043]
Furthermore, the present invention can also be applied to a heat pump system in which an outdoor heat exchanger is additionally installed in the refrigeration cycle 40 and the refrigerant flow can be switched to obtain a heating function.
Further, the evaporator intake air temperature TIN may be calculated from the inside air temperature, the outside air temperature, and the inside / outside air ratio. Thereby, the evaporator intake air temperature sensor 74 can be omitted.
[0044]
In addition, the traction motor (motor generator) 2 is driven to generate electric power, but a generator is separately provided, and the generator 4 is driven by the engine 1 to charge the battery 4. Good.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a schematic configuration of a hybrid vehicle equipped with an air conditioner according to an embodiment of the present invention.
2 is a schematic diagram showing an overall configuration of the air conditioner shown in FIG. 1. FIG.
FIG. 3 is a block diagram showing a control system of the air conditioner shown in FIG. 1;
4 is a plan view of the control panel shown in FIG. 3. FIG.
FIG. 5 is a flowchart showing a basic control process of the air conditioner control device shown in FIG. 1;
6 is a flowchart showing a control process in step S9 of FIG.
FIG. 7 is a flowchart showing basic control processing of the vehicle control apparatus shown in FIG. 1;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Engine for driving, 2 ... Motor for driving (motor generator), 4 ... Battery,
6 ... Air conditioning unit.

Claims (7)

A traveling engine (1), a traveling motor (2), a battery (4) for supplying electric power to the traveling motor (2), and the battery (4) driven by the traveling engine (1) And a generator (2) that charges the battery (4) when the remaining charge of the battery (4) falls below a target value. To be installed,
An air conditioner unit (6) which is supplied with electric power from the battery (4) and air-conditions the vehicle interior;
Calculating the required air conditioning power required by the air conditioner unit (6) to adjust the temperature in the passenger compartment to a set temperature arbitrarily set;
The hybrid vehicle air conditioner is characterized in that the target value is set higher with an increase in the required air conditioning power during vehicle travel. The hybrid vehicle according to claim 1, wherein the power consumption of the air conditioner unit (6) is limited to a predetermined value smaller than the required air conditioning power as the remaining charge of the battery (4) decreases. Air conditioner. 3. The hybrid vehicle air conditioner according to claim 1, wherein the electric power used by the air conditioner unit is limited to a predetermined value smaller than the required air conditioning power while the vehicle is stopped. The air conditioner for a hybrid vehicle according to any one of claims 1 to 3, wherein the target value is set lower when the vehicle is stopped than when the vehicle is running. The power consumption of the air conditioner unit (6) is prohibited from being restricted when the air conditioning heat load is large and the defroster mode is in a state where air is blown to the vehicle window glass. 3. The hybrid vehicle air conditioner according to 3. The said air conditioner unit (6) has an electric compressor (41) which receives electric power from the said battery (4), and act | operates and compresses a refrigerant | coolant, The one of Claim 1 thru | or 5 characterized by the above-mentioned. Air conditioner for hybrid vehicles. The air conditioner for a hybrid vehicle according to any one of claims 1 to 6, wherein the travel motor (2) is a motor generator that also serves as the generator (2).

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