JP4566370B2 - Air conditioner for vehicles - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle air conditioner, and more particularly to a vehicle air conditioner provided with a cooling fan for an outdoor heat exchanger of a refrigeration circuit.
[0002]
[Prior art]
A conventional vehicle air conditioner is configured as shown in FIG. 7, for example, and the cooling fan is controlled as shown in FIG. In FIG. 7, an indoor heat exchanger, for example, an evaporator 102 is provided in an air conditioning duct 101 that leads to the vehicle interior, and an outdoor heat exchanger, for example, a condenser 103 is provided outside the air conditioning duct 101. A compressor driven by the engine 104, for example, a refrigerant sent from a variable capacity compressor 105 through the condenser 103 is expanded by the expansion valve 106 and supplied to the evaporator 102, and the refrigerant from the evaporator 102 is supplied. A refrigeration circuit 107 is configured to be returned to the compressor 105.
[0003]
The refrigeration circuit 107 is provided with a cooling fan 108 that generates a cooling air flow for the condenser 103 and a motor 109 that drives the cooling fan 108. The cooling fan motor 109 is on / off controlled in conjunction with the operation of the refrigerant compressor 105 of the refrigeration cycle. That is, on / off control is performed via the cooling fan motor on / off control means 112 in conjunction with the compressor clutch control signal 111 from the main controller 110.
[0004]
Alternatively, when the cooling fan motor 109 also serves as a cooling fan motor for the radiator in addition to the outdoor heat exchanger 103 of the refrigeration cycle, the signal from the vehicle speed sensor 113 and the engine cooling water temperature sensor 114 In consideration of the signal, a predetermined voltage is applied to the cooling fan motor 109.
[0005]
Therefore, as shown in FIG. 8, the cooling fan motor 109 is controlled via the cooling fan motor on / off control means 112 in accordance with the compressor clutch signal Sm, or in addition to the vehicle speed signal SP and the engine cooling water signal Tw. Is controlling. In any case, the cooling fan motor 109 relies on simple on-off control, high-low two-stage voltage control, or at most high-low-off three-stage voltage control.
[0006]
[Problems to be solved by the invention]
However, in the control of the conventional cooling fan motor as described above, basically, only two-step control of on / off or high / low of voltage is performed, and air conditioning is used to derive the control voltage of the cooling fan motor. Since the total power consumption of the apparatus is not taken into consideration, the cooling fan motor may not be operated in a state where the total power consumption is optimal. Therefore, the operation of the cooling fan motor increases the total power consumption of the air conditioner, which may increase the fuel consumption of the vehicle engine.
[0007]
In addition, only two-stage control of on-off or voltage high-low is performed, and cooling control considering the heat radiation amount of the condenser (outdoor heat exchanger) is not performed for the refrigeration cycle. The stability of the refrigeration cycle may be reduced. If the refrigeration cycle is unstable, the duct blowing air temperature will not be stable.
[0008]
Furthermore, since there are only two-stage control states of on-off or voltage high-low, the cooling fan motor speed may become higher than necessary even when the heat dissipation of the condenser is not so much needed. Yes, it may cause noise. In addition, unnecessarily operating at a high rotational speed for a long time may cause a decrease in the life of the cooling fan motor.
[0009]
Therefore, the object of the present invention is to focus on the problems in the conventional control as described above, and to optimize the drive control of the cooling fan motor for the outdoor heat exchanger, thereby suppressing the total power consumption of the entire air conditioner. It is possible to reduce the fuel consumption of the vehicle engine.
[0010]
In addition, the problem of the present invention is to improve the stability of the refrigeration cycle by optimizing the drive control of the cooling fan motor, to improve the stability of the duct blowout air temperature, and at the low rotation speed of the cooling fan motor. It is to increase the operation opportunity of the system, extend its life and reduce noise.
[0011]
[Means for Solving the Problems]
In order to solve the above problems, a vehicle air conditioner according to the present invention includes an indoor heat exchanger provided in an air conditioning duct, an outdoor heat exchanger provided outside the air conditioning duct, and a variable capacity type driven by an engine. In a vehicle air conditioner having a refrigeration circuit including a compressor, a cooling fan that generates a cooling airflow for the outdoor heat exchanger, and a motor that drives the cooling fan, at least the temperature of the cooling airflow An outside air temperature recognizing means for detecting the vehicle speed, a vehicle speed recognizing means for recognizing the traveling vehicle speed of the vehicle, and a cooling fan motor control amount calculating means for calculating the control amount of the cooling fan motor with reference to the recognized value of each recognizing means; Cooling fan motor drive control means for variably controlling the drive control amount of the cooling fan motor in accordance with the calculated control amount, and the compressor and the cooling fan motor are provided. The air conditioner equipment power consumption calculating means for calculating the total power consumption W of the air conditioner equipment is provided, and the cooling fan motor control amount calculating means first calculates the target value Vp of the cooling fan motor voltage to obtain the cooling fan. After the motor voltage Vf is operated so as to approach the target value Vp, the cooling fan motor voltage Vf is repeatedly calculated and controlled in a direction to decrease or increase with a certain voltage change width ΔV so that the total power consumption W decreases. when the total power consumption W is started to increase reverses the direction of increasing or decreasing the operation direction of the cooling fan motor voltage Vf while halving the voltage change width [Delta] V, have repeated rows series of operations and control, further The cooling fan motor control amount calculation means calculates the cooling fan motor voltage change width ΔV and V in the calculation of the cooling fan motor voltage Vf. And / or when the difference between the previous value and the current value of the total power consumption W is smaller than a predetermined value, or when a certain time has passed while the difference between ΔV and / or W is smaller than a predetermined value, A part of data that is each parameter value for deriving a target cooling fan motor voltage Vp formula stored in advance is updated, and a new calculation formula for the target cooling fan motor voltage Vp is calculated from the updated data by the least square method. And the current calculation formula is updated to a newly calculated calculation formula for the target cooling fan motor voltage Vp .
[0012]
In the vehicle air conditioner, the cooling fan motor control amount calculating means has a certain voltage change width ΔV in the direction in which the total power consumption W decreases in the calculation of the cooling fan motor voltage Vf, and the cooling fan motor voltage. When Vf is repeatedly calculated and controlled in a direction to decrease or increase and the total power consumption W starts to increase, the voltage change width ΔV is halved and the operation direction of the cooling fan motor voltage Vf is reversed to increase or decrease. The series of operations and control is repeated .
[0013]
Further, the cooling fan motor control amount calculation means is configured such that, in the calculation of the cooling fan motor voltage Vf, the difference between the previous value and the current value of the change width ΔV of the cooling fan motor voltage and / or the total power consumption W is smaller than a predetermined value. Or a parameter value for deriving a target cooling fan motor voltage Vp stored in advance when a certain time elapses while the difference between ΔV and / or W is smaller than a predetermined value , A new calculation formula for the target cooling fan motor voltage Vp is derived from the updated data by the least square method, and the current calculation formula is newly calculated. To update .
[0014]
Further, the cooling fan motor control amount calculation means calculates the target cooling fan motor voltage Vp with reference to the recognition value by the outside air temperature recognition means and the recognition value by the vehicle speed recognition means in the calculation of the cooling fan motor voltage Vf. It is preferable.
[0015]
Further, the cooling fan motor control amount calculating means repeatedly calculates the target cooling fan motor voltage Vp with reference to the recognized value by the outside air temperature recognizing means and the recognized value by the vehicle speed recognizing means in the calculation of the cooling fan motor voltage Vf, When the difference ΔVp between the previous Vp and the current Vp becomes a value outside the predetermined range, it is preferable to perform the calculation operation of the cooling fan motor voltage Vf from the beginning based on the new Vp this time.
[0016]
In the vehicle air conditioner according to the present invention as described above, when the voltage of the cooling fan motor is derived by calculation, the calculated value of the total power consumption W of each device for the air conditioner is considered, and the state at that time is Accordingly, the optimal control voltage is calculated so that the total power consumption becomes small. Accordingly, useless power consumption is suppressed, and the total power consumption of the entire air conditioner is reduced. As a result, the fuel consumption of the vehicle engine is also reduced.
[0017]
In addition, since the drive control of the cooling fan motor is optimized steplessly, the heat dissipation state of the outdoor heat exchanger is optimally adjusted steplessly, thereby suppressing the fluctuation of the refrigerant state in the refrigeration cycle. As a result, fluctuations in the heat exchange performance in the indoor heat exchanger are suppressed to a small level, and the stability of the duct blowing air temperature is improved.
[0018]
In addition, the stepless optimum control of the cooling fan motor increases the operating time at a low rotation speed compared to the conventional two-step control of on / off or high / low voltage, and the total consumption of the air conditioner described above. Extending the life of the cooling fan motor and reducing noise are achieved while reducing power.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a vehicle air conditioner according to an embodiment of the present invention. In FIG. 1, an evaporator 2 as an indoor heat exchanger is provided in an air conditioning duct 1, and a condenser 3 as an outdoor heat exchanger is provided outside the air conditioning duct 1. The refrigerant compressed by the variable displacement compressor 5 (variable displacement compressor) driven by the vehicle engine 4 is condensed by the condenser 3 and sent to the evaporator 2 via the receiver 6 and the expansion valve 7 for evaporation. The refrigeration circuit 8 is configured so as to be returned from the container 2 to the compressor 5. A capacity control signal is sent from the main controller 9 to the compressor 5, and a pressure detection signal is sent from the high pressure sensor 10 provided on the high pressure side of the refrigeration circuit 8 to the main controller 9.
[0020]
A cooling fan 11 for generating a cooling air flow is provided for the condenser 3 of the refrigeration circuit 8, and the cooling fan 11 is driven by a cooling fan motor 12. The driving of the cooling fan motor 12 is controlled via a cooling fan voltage controller 13 as a cooling fan motor drive control means based on a cooling fan motor control amount signal from the main controller 9 as a cooling fan motor control amount calculation means. The In order to calculate the cooling fan motor control amount, the main controller 9 receives a vehicle speed signal from the vehicle speed sensor 14 as the vehicle speed recognition means, an outside air temperature signal from the outside air temperature sensor 15 as the outside air temperature recognition means, and a cooling water temperature. A coolant temperature signal from the engine coolant temperature sensor 16 as a recognition means, a vehicle interior temperature signal from the vehicle interior temperature sensor 17 as a vehicle interior temperature recognition means, an evaporator outlet air temperature sensor provided downstream of the evaporator 2 A signal from 18 is input.
[0021]
On the inlet side of the air conditioning duct 1, an intake air amount switching damper 23 between the outside air introduction port 21 and the inside air introduction port 22 is provided, and an intake actuator 24 for adjusting it is provided. Further, a blower voltage controller 27 for controlling the voltage of the fan 25 of the blower and its motor 26 is provided. In the present embodiment, a warm water heater 28 through which engine coolant is passed is provided on the downstream side of the evaporator 2, and an air mix damper 29 is provided on the downstream side thereof. The opening degree of the air mix damper 29 is controlled via the air mix damper actuator 30 based on a signal from the main controller 9.
[0022]
Reference numerals 31, 32, and 33 denote temperature-controlled air outlets into the vehicle interior, and dampers 34, 35, and 36 for opening adjustment are provided at the outlets, respectively. In this embodiment, an electric heater 37 is provided at the air outlet 33, and the voltage of the electric heater 37 is controlled via the electric heater voltage controller 38 based on a signal from the main controller 9.
[0023]
In the main controller 9, the cooling fan motor control amount is calculated as shown in FIGS.
The flowcharts shown in FIGS. 2 and 3 show the main routine, and first enter a subroutine in step S1. In the subroutine, as shown in FIG. 4, the outside air temperature Tout and the vehicle speed SP are input (steps S101 and S102), and the target cooling fan motor voltage Vp is
Vp = f (Tout, SP)
(Step S103). First, the initial value V0 of the target cooling fan motor voltage is input, and the difference between the target cooling fan motor voltage Vp (current value) and the previous target cooling fan motor voltage Vp ′ is calculated (steps S104 and S105). ).
[0024]
Returning to the main routine shown in FIG. 2, the cooling fan motor control voltage change width ΔVa obtained by halving the target cooling fan motor voltage ΔVp is added to the previous cooling fan motor control voltage Vf ′ to obtain a new cooling fan motor control voltage Vf. After the operation, the total power consumption W0 of the air conditioner is calculated (steps S2 to S5).
[0025]
Subsequently, the cooling fan motor control voltage change width ΔVa is added to the previous cooling fan motor control voltage Vf ′ (Vf in step S4), and after operating as a new cooling fan motor control voltage Vf, the total power consumption W1 of the air conditioner is calculated. Calculate (steps S6 to S8). Subsequently, the subroutine of FIG. 4 is executed (step S9), and it is determined whether or not the target cooling fan motor voltage change amount ΔVp is within a range of ± A (predetermined value) (step S10). For example, the total power consumption W0 and W1 of the air conditioner are compared (step S11). Comparing the total power consumption W0 and W1 of the air conditioner, if W1 is large, as shown in FIG. 3, ΔVb, which is half the cooling fan motor control voltage change width ΔVa, is set to the previous cooling fan motor control voltage Vf. After subtracting from 'and operating as a new fan control voltage Vf, the total power consumption W2 of the air conditioner is calculated (steps S12 to S15). Subsequently, the subroutine of FIG. 4 is executed (step S16), and if the target cooling fan motor voltage change amount ΔVp is within the range of ± A, the total power consumption W1 and W2 of the air conditioner consumption power are compared (steps S17, S18). ).
Comparing the total power consumption W1 and W2 of the air conditioner, W2 is large and the cooling fan motor control voltage change width ΔVb is within a range of ± B (predetermined value), and the absolute value of the difference between W1 and W2 is C Is smaller than the current outside air temperature Tout, the vehicle speed SP, and the cooling fan motor control voltage Vf are stored in the memory (steps S19 and S20).
[0026]
A target cooling fan motor voltage Vp formula is derived from the stored information by a least square approximation method (step S21), and the current Vp formula (Vp formula in FIG. 4) is updated to a new Vp formula (step S22). Return to START in the flowchart.
[0027]
When the target cooling fan motor voltage change amount ΔVp is not within the range of ± A in step S10, the process returns to step S2. If W0 <W1 is not satisfied in step S11, the process returns to step S6. When ΔVp is not within the range of ± A in step S17, the process returns to step S2, and when W1 <W2 is not satisfied in step S18, the process returns to step S13. Further, when step S19 is not established, the process returns to step S12 repeatedly.
[0028]
In the above flowchart, the total consumed power W is calculated as shown in FIG. 5, for example. Further, the expression of the target cooling fan motor voltage Vp in the flowchart is derived as shown in FIG. 6, for example.
[0029]
In the example shown in FIG. 5, as the detected amounts, the evaporator outflow air temperature Teout, the outside air temperature Tout, the inside air temperature Tin, the intake state INT, the blower voltage calculation value BLV, the compressor capacity control signal Ic, the high pressure Pd, the cooling fan motor The voltage Vfan, battery voltage VB, and electric heater voltage Vh are detected. Evaporator inflow air temperature Tein,
Tein = Tout × α + Tin × (1−α)
To calculate the refrigerant flow rate Gr,
Gr = f (Qe, ΔIe)
Calculate with. However,
Qe = f (Tein, BLV, Teout)
ΔIe = f (Ps, Pd)
Ps = f (Ic)
It is. here,
Qe: cooling capacity ΔIe: evaporator enthalpy difference Ps: compressor suction pressure.
[0030]
And compressor power consumption Wcmp,
Wcmp = f (Gr, Ps, Pd)
Calculate with
Ps = f (Ic)
It is.
[0031]
In addition, power consumption Welc for air conditioners other than the compressor
Welc = η × f (Wfan, Wcl, Wblv, Wh)
Ask for. However,
Wfan = f (Vfan)
Wcl = f (VB)
Wblv = f (BLV)
Wh = f (Vh)
η: Alternator efficiency.
[0032]
The total W of the compressor power consumption Wcmp and other power consumption Welc is
W = Wcmp + Welc
As required.
[0033]
FIG. 6 shows the concept of obtaining the arithmetic expression for the target cooling fan motor voltage Vp in the subroutine of FIG.
[0034]
As shown in FIG. 6, the total power consumption of the air conditioner is the sum of the compressor power consumption Wcomp and the various electric equipment consumption power Welc. The various electric equipment power consumption includes an alternator for the power generated by the prime mover (engine).・ Power with the added efficiency of the regulator is consumed. The compressor consumption power Wcomp is subject to various conditions (evaporator outflow air temperature Teout, outside air temperature Tout, inside air temperature Tin, intake state INT, blower voltage calculation value BLV, compressor capacity control signal Ic, high pressure Pd of the refrigeration circuit). Power consumption generated according to the electric power consumption, and electric device consumption power Welc is also a power consumption generated according to various conditions (cooling fan motor use voltage Vfan, battery voltage VB, electric heater voltage Vh, blower voltage calculation value BLV). .
[0035]
The correlation (correlation data) between the total power consumption W of the air conditioner, which is the sum of these power consumptions, and the cooling fan motor voltage Vfan (that is, the actual drive control amount of the cooling fan motor) is represented by each parameter (each explanation). Variable). That is, correlation is obtained for each explanatory variable, with Vfan being an objective variable, that is, the target cooling fan motor voltage Vp, and each parameter being an explanatory variable. Then, the outside air temperature Tout and the vehicle speed SP are used as explanatory variables, and the cooling fan motor voltage Vp is used as an objective variable to obtain a correlation. The correlation between Vfan (Vp) and W is data having the lowest extreme value (minimum value) as shown in the figure for each explanatory variable. By controlling to the minimum value Wmin or Vfan (Vp) which becomes W in the vicinity thereof, the power consumption of the cooling fan motor can be optimally reduced according to the conditions at that time. With simple on / off control of the cooling fan motor voltage and high / low two-stage control, it is impossible to reduce the power consumption of the cooling fan motor and optimize the cooling fan motor voltage control according to the conditions at that time.
[0036]
Based on such a technical idea, a correlation equation f between the objective variable and the explanatory variable is derived from the correlation data.
Vp = f (Tout, SP)
The correlation equation is derived, and using this correlation equation, calculation is performed as shown in the subroutine of FIG. 4 described above, and a command signal to be actually output to the cooling fan motor voltage controller 13 according to the condition at that time is calculated. decide.
[0037]
In such control, the voltage of the cooling fan motor can be optimally controlled substantially steplessly according to the state of the vehicle and the air conditioner at that time. In other words, the cooling fan motor voltage is controlled so that the total power consumption of the air conditioner is as small as possible, and at the same time, fluctuations in the refrigerant state of the refrigeration cycle are suppressed, and fluctuations in the temperature of the duct blowing air are suppressed. . Since the total power consumption of the air conditioner is kept small, the fuel consumption of the vehicle engine is kept low, and the stability of the duct blowing air temperature is ensured by stabilizing the refrigeration cycle.
[0038]
In addition, since the opportunity to operate the cooling fan motor at a low rotational speed increases, the life of the cooling fan and its motor can be extended and noise can be reduced.
[0039]
【The invention's effect】
As described above, according to the vehicle air conditioner of the present invention, it is possible to optimally control the power to be used for the cooling fan according to the state at that time in consideration of the total power consumption of the air conditioner. As a result, the power consumption of the cooling fan, and thus the total power consumption of the air conditioner, can be reduced, and the fuel consumption of the vehicle engine can be reduced.
[0040]
In addition, since the cooling fan can be optimally controlled in a substantially stepless manner, the stability of the duct blowout air temperature can be improved, and the cooling fan can be operated at low speeds, thus extending its life and reducing noise. It is also possible to measure.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a vehicle air conditioner according to an embodiment of the present invention.
FIG. 2 is a flowchart showing control of the apparatus shown in FIG.
FIG. 3 is a flowchart showing a continuation of the flow of FIG.
4 is a flowchart showing a subroutine in the flow of FIG.
5 is a block diagram showing an example of total power consumption calculation in the flow of FIG.
6 is an explanatory diagram showing an example of deriving a target cooling fan motor voltage calculation formula in the subroutine of FIG. 4. FIG.
FIG. 7 is a schematic configuration diagram of a conventional vehicle air conditioner.
FIG. 8 is a block diagram showing control of the apparatus shown in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Air conditioning duct 2 Evaporator as indoor heat exchanger 3 Condenser as outdoor heat exchanger 4 Vehicle engine 5 Variable capacity compressor 6 Receiver 7 Expansion valve 8 Refrigeration circuit 11 Cooling fan 12 Cooling fan motor 13 Cooling fan Voltage controller 14 Vehicle speed sensor 15 Outside air temperature sensor 16 Engine coolant temperature sensor 17 Car interior temperature sensor 18 Evaporator outlet air temperature sensor 21 Outside air introduction port 22 Inside air introduction port 23 Switching damper 24 Intake actuator 25 Blower fan 26 Blower motor 27 Blower voltage Controller 28 Hot water heater 29 Air mix damper 30 Air mix damper actuator 31, 32, 33 Air outlet 34, 35, 36 Damper 37 Electric heater 38 Electric heater voltage controller

Claims (3)

An indoor heat exchanger provided in the air conditioning duct, an outdoor heat exchanger provided outside the air conditioning duct, a refrigeration circuit having a variable capacity compressor driven by an engine, and cooling the outdoor heat exchanger In a vehicle air conditioner having a cooling fan for generating an air flow and a motor for driving the cooling fan, at least an outside air temperature recognition means for detecting the temperature of the cooling air flow, and a vehicle speed recognition for recognizing the traveling vehicle speed of the vehicle And a cooling fan motor control amount calculation means for calculating a control amount of the cooling fan motor with reference to the recognition value of each recognition means, and the drive control amount of the cooling fan motor is variable according to the calculated control amount A cooling fan motor drive control means for controlling is provided, and the total power consumption W of the air conditioner equipment including the compressor and the cooling fan motor is repeatedly calculated. An air conditioner equipment power consumption calculating means is provided, and the cooling fan motor control amount calculating means first calculates a target value Vp of the cooling fan motor voltage and operates so that the cooling fan motor voltage Vf approaches the target value Vp. The cooling fan motor voltage Vf is repeatedly calculated and controlled in a direction to decrease or increase with a certain voltage change width ΔV so that the total power consumption W decreases, and when the total power consumption W starts to increase, the voltage change width ΔV cooling the operating direction of the fan motor voltage Vf is reversed in the direction of increasing or decreasing, have repeated rows series of operations and control, further the cooling fan motor control amount calculating means as well as the half, the cooling fan motor voltage Vf The difference between the previous value and the current value of the cooling fan motor voltage change width ΔV and / or the total power consumption W Each time for deriving a target cooling fan motor voltage Vp expression stored in advance when the difference is smaller than a fixed value or when a certain time has passed while the difference between ΔV and / or W is smaller than a predetermined value. A part of the parameter value data is updated, a new calculation formula for the target cooling fan motor voltage Vp is derived from the updated data by the least square method, and the current calculation formula is newly calculated. A vehicle air conditioner that is updated to a calculation formula for the voltage Vp . Cooling fan motor control amount calculating means, the operation of the cooling fan motor voltage Vf, by referring to the recognition value by the recognition value and the vehicle speed recognizing means according to the outside air temperature recognition means for calculating a target cooling fan motor voltage Vp, of claim 1 Vehicle air conditioner. The cooling fan motor control amount calculation means repeatedly calculates the target cooling fan motor voltage Vp by referring to the recognition value by the outside air temperature recognition means and the recognition value by the vehicle speed recognition means in the calculation of the cooling fan motor voltage Vf. The vehicle air conditioner according to claim 2 , wherein when the difference ΔVp of the current Vp becomes a value outside a predetermined range, the calculation operation of the cooling fan motor voltage Vf is performed from the beginning based on the new current Vp.

Images