KR20100091507A - Control method of air conditioner for vehicle - Google Patents

Abstract

PURPOSE: A method for controlling an air conditioner for a vehicle is provided to maximize air conditioning ability by controlling ECV duty and to increase ECV duty when necessary. CONSTITUTION: A method for controlling an air conditioner for a vehicle is as follows. ECV calculation duty for controlling the discharged amount of refrigerants of a compressor is calculated. The compressor is controlled by outputting the calculated ECV calculation duty to ECV control duty. When the ECV calculation is approached to a critical value, the compressor is controlled by maximally increasing the ECV control duty.

Description

Control method of air conditioner for vehicle {Control method of air conditioner for vehicle}

The present invention relates to a vehicle air conditioner, and more particularly, to a control method of a vehicle air conditioner that can improve the cooling performance of the air conditioner by increasing the ECV duty to the maximum value in some cases.

An air conditioner is installed in a car for cooling and cooling indoors. In such an air conditioner, a swash plate type compressor is a compressor configured to compress a low-temperature low-pressure gaseous refrigerant drawn from an evaporator into a high-temperature high-pressure gaseous refrigerant to a condenser. Is being applied.

The swash plate compressor is driven according to the on / off of the air conditioner switch. When the compressor is driven, the temperature of the evaporator is lowered, and when the compressor is stopped, the temperature of the evaporator is increased.

On the other hand, such swash plate type compressors include a fixed displacement type and a variable displacement type. These compressors are driven by receiving power from the rotational force of an automobile engine. The fixed displacement type electronic clutch is provided to control the driving of the compressor. However, when the electronic clutch is provided, there is a problem in that the RPM of the vehicle flows when the compressor is driven or stopped, thereby preventing stable vehicle operation.

Therefore, in recent years, a clutch is not provided, and a swash plate is always rotated with the driving of the engine, but a variable capacitance type that can change the discharge capacity by changing the inclination angle of the swash plate is mainly used.

Such a variable displacement swash plate compressor generally uses a pressure regulating valve for adjusting the inclination angle of the swash plate to adjust the amount of refrigerant discharge. Recently, a swash plate inclination control valve (hereinafter referred to as 'ECV') is driven by electrical control. Is used.

Accordingly, in the case of a variable displacement swash plate type compressor employing ECV, the inclination of the swash plate is changed by the duty of the ECV or the applied current value to the ECV, and the amount of refrigerant discharged from the compressor is determined by the inclination of the swash plate.

As a result, the amount of refrigerant supplied to the evaporator is changed according to the duty or applied current value of the ECV, which means that the duty or applied current value of the ECV is a major factor in determining the evaporator temperature. It means that the refrigerant is discharged to more than zero).

The above-mentioned ECV duty is a value indicating a percentage of time that the ECV is on during the entire time. Therefore, the refrigerant discharge of the compressor increases when the duty is high, and decreases when the duty is low.

On the other hand, such ECV duty is in principle adjustable from 0% to 100%, but is designed to be adjusted only within a certain range due to the characteristics of the variable displacement swash plate compressor. It is designed that the amount of regulation of the ECV duty is designed so that the air conditioner is optimized under certain conditions (e.g., when the control supply voltage is 14V in the normal power generation state of the alternator, or when the applied current value is constant to a certain value). This is because the ECV duty above a certain ratio is relatively large compared to the increase in the air conditioner's performance difference.

Therefore, conventionally, the ECV duty is controlled so as not to increase by a certain ratio or more. As shown in FIG. 1, when the actual temperature of the evaporator is higher than the evaporator target temperature, the ECV duty is steadily increased by feedback control, but when the ECV duty reaches a certain ratio (shown at 85% in the drawing). It no longer increases it. Then, as the evaporator temperature decreases and approaches the evaporator target temperature, the ECV duty is gradually lowered to maintain the evaporator temperature close to the target temperature.

However, this method is not suitable for conditions outside of certain conditions because the ECV duty is controlled to optimize the air conditioner under certain conditions. As described above, the amount of refrigerant supplied to the evaporator varies according to the duty and the applied current value of the ECV. If it is assumed that the applied current value is a constant value, it may be appropriate to adjust the ECV duty by the method described above. When the applied current value is lower than the specified value, for example, when the applied voltage value from the alternator is lowered, the voltage applied to the ECV is reduced and accordingly the applied current value is lowered, or the temperature is increased to increase the resistance of the ECV. When the current value rises and the applied current value decreases, the amount of refrigerant supplied to the evaporator is reduced even by the same ECV duty control scheme. As a result, the cooling power of the air conditioning apparatus is lowered, which hinders the pleasant air conditioning environment.

Therefore, in such a case, it is necessary to raise the ECV duty to the maximum value (100%) to compensate for the falling of the applied current value.

Accordingly, the present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to provide an air conditioner control method capable of optimizing the air conditioning function by controlling the ECV duty not limited to a certain range.

Another object of the present invention is to provide an air conditioner control method capable of compensating for this by increasing the ECV duty when the applied current value of the ECV becomes low.

The present invention for the above object, (A) calculating the ECV calculation duty for adjusting the refrigerant discharge capacity of the compressor of the vehicle air conditioner according to the evaporator temperature and the target temperature of the evaporator; (B) controlling the compressor by outputting the ECV calculation duty calculated in step (A) as an ECV control duty; (C) during the execution of step (B), when the ECV calculation duty increases to reach a threshold value; Controlling the compressor by increasing the ECV control duty to a maximum value; And (D) if a predetermined condition is satisfied in step (C), controlling the compressor by dropping the ECV control duty from the maximum value to the threshold value, and using the ECV calculation duty as the ECV control duty. Including to perform.

At this time, the step (C), (C11) if the ECV calculation duty reaches a threshold, monitoring the increase and decrease of the evaporator temperature while maintaining the ECV control duty at a threshold; And (C12) increasing the ECV control duty from the threshold value to the maximum value if the evaporator temperature does not decrease for more than a predetermined time, thereby controlling the compressor while maintaining the ECV control duty at the maximum value. Can be performed.

In addition, the step (C), (C21) when the ECV calculation duty reaches a threshold value, increasing the ECV control duty to a maximum value; And (C22) controlling the compressor while maintaining the ECV control duty at the maximum value.

And (C) step (C31) controlling the compressor according to the ECV control duty while constantly raising the ECV control duty from the threshold to the maximum value when the ECV calculation duty reaches a threshold. step; And (C31) if the ECV control duty reaches the maximum value, controlling the compressor while maintaining the ECV control duty at the maximum value.

Meanwhile, in the step (D), the predetermined condition may be satisfied by the ECV calculation duty falling below the threshold, or by the evaporator temperature starting to fall.

Here, the control method of the air conditioning apparatus, when the intensity of the current applied to the ECV (swash plate inclination control valve) of the air conditioning apparatus is more than a set value, performing only the steps (A) and (B) to operate the compressor To control; When the intensity of the current applied to the ECV of the air conditioner is less than the set value, it may be performed including the step of controlling the compressor by performing all the steps (A) to (D).

In the control method of the vehicle air conditioner according to the present invention as described above can be expected the following effects.

That is, there is an advantage that the air conditioning capacity can be maximized by controlling the ECV duty not limited to a certain range.

In addition, the control method of the automotive air conditioner according to the present invention has the advantage that can be compensated by increasing the ECV duty when the applied current value of the ECV is lowered.

Hereinafter, with reference to the accompanying drawings a specific embodiment of the air conditioner control method according to the present invention as described above will be described in detail.

First, the configuration of a variable displacement swash plate compressor applied to the present invention will be briefly described with reference to FIG. 2. 2 is a cross-sectional view showing the internal configuration of a variable displacement swash plate compressor.

As shown therein, a center bore 11 is formed through the center of the cylinder 10 of the variable displacement swash plate compressor according to the present invention, and the cylinder 10 radially surrounding the center bore 11. A plurality of cylinder bores 13 are formed to penetrate. The piston 15 is movable in the cylinder bore 13 to compress the refrigerant in the cylinder bore 13.

Meanwhile, the front housing 20 is installed at one end of the cylinder 10. The front housing 20 cooperates with the cylinder 10 to form a crank chamber 21 therein.

And the other end of the cylinder 10, that is, the rear housing 30 is installed on the opposite side where the front housing 20 is installed. The rear housing 30 is formed with a suction chamber 31 in selective communication with the cylinder bore 13. At this time, the suction chamber 31 serves to deliver the refrigerant to be compressed into the cylinder bore 13.

In addition, a discharge chamber 33 is formed in the rear housing 30. The discharge chamber 33 is formed in an area corresponding to the center of the surface of the rear housing 30 facing the cylinder 10. The discharge chamber 33 is a place where the refrigerant compressed in the cylinder bore 13 is discharged and temporarily stays. One side of the rear housing 30 is provided with a control valve 35, the control valve 35 to adjust the opening degree of the flow path between the discharge chamber 33 and the crank chamber 21 to be described later swash plate 48 ) Is to adjust the angle.

On the other hand, the drive shaft 40 is rotatably installed through the center bore 11 of the cylinder 10 and the shaft hole 23 of the front housing 20. The drive shaft 40 is rotated by the driving force transmitted from the engine. The drive shaft 40 is rotatably installed by the bearing 42 in the cylinder 10 and the front housing 20.

The rotor 44 is installed in the crank chamber 21 so that the drive shaft 40 penetrates the center and rotates integrally with the drive shaft 40. At this time, the rotor 44 is fixed to the drive shaft 40 in a substantially disk shape, the hinge arm 46 is formed on one surface of the rotor 44 protruding.

The drive shaft 40 is installed so that the swash plate 48 is hinged to the rotor 44 and rotated together. The swash plate 48 is installed at a variable angle to the drive shaft 40 according to the discharge capacity of the compressor. That is, between the state orthogonal to the longitudinal direction of the drive shaft 40 or the state inclined at a predetermined angle with respect to the drive shaft 40. The swash plate 48 has its edge 50 connected to the pistons 15 via a shoe 50. That is, the edge of the swash plate 48 is connected to the connecting portion 17 of the piston 15 through the shoe 50 so that the piston 15 is straight in the cylinder bore 13 by the rotation of the swash plate 48. Reciprocate.

The swash plate 48 is formed to protrude a connecting arm 52 which is connected to the hinge arm 46 of the rotor 44. A hinge pin 54 is installed at a tip end of the connecting arm 52 in a direction orthogonal to the longitudinal direction of the connecting arm 52, and the hinge pin 54 is formed of the hinge arm 46 of the rotor 44. It is movably hung on the support part 47 formed in the front-end | tip.

A radial yarn spring 56 is installed to exert an elastic force between the rotor 44 and the swash plate 48. The radial yarn spring 56 is installed around the outer surface of the drive shaft 40 and exerts an elastic force in a direction in which the inclination angle of the swash plate 48 decreases.

The swash plate stopper 58 is formed to protrude from one surface of the swash plate 48. The swash plate stopper 58 serves to regulate the degree to which the swash plate 48 is inclined inclined with respect to the drive shaft 40.

One end of the drive shaft 40 is provided with a shaft stopper (60). The shaft stopper 60 is installed around the outer surface of the drive shaft 40, and when the swash plate 48 is erected in a direction perpendicular to the longitudinal direction of the drive shaft 40, it serves to regulate the installation position do.

On the other hand, Figure 3 is a block diagram showing the configuration of the air conditioner control unit and the engine control system provided in the present invention.

As shown therein, the vehicle air conditioner according to the present invention comprises an air conditioner control unit 100 for controlling the operation of the air conditioner and the operation of the components constituting the air conditioner.

To this end, the air conditioner control unit 100 includes a main controller 120. The main controller 120 receives various information from the detection unit 200 to be described later, calculates and delivers an ECV duty for adjusting the discharge capacity of the compressor 300 to be described later in order to adjust the temperature in the vehicle to a desired temperature. do.

That is, the ECV duty for adjusting the discharge capacity of the compressor 300 is calculated and transmitted to the ECV driver 160 which will be described later.

First, the main controller 120 receives vehicle state information such as the inside temperature of the vehicle, the outside air temperature, the evaporator temperature, the refrigerant pressure, and the like from the detection unit 200. The main controller 120 compares the above information with preset values to calculate the ECV duty.

First, the main controller 120 receives the target temperature of the vehicle interior input by the occupant of the vehicle and compares it with the current indoor temperature. Further, the target temperature of the evaporator is determined based on the target temperature of the vehicle interior and the current indoor temperature.

The target discharge capacity of the refrigerant of the compressor 300 is determined by comparing the target temperature of the evaporator with the present temperature of the evaporator received from the detection unit 200. The ECV duty is determined by comparing the determined target discharge capacity with the current discharge capacity detected through the information such as the refrigerant pressure received from the detection unit 200, or the ECV duty is fed back according to the target temperature and the current temperature difference of the evaporator. To control.

The ECV duty values corresponding to the target temperature of the evaporator or the refrigerant target discharge capacity of the compressor calculated in this case are previously stored in the memory 140 to control the air conditioner accordingly.

At this time, the main controller 120 controls the determined ECV duty value according to the change of the current discharge capacity or the change of the evaporator temperature. That is, the ECV duty value is determined to adjust the discharge capacity and the evaporator temperature of the refrigerant of the compressor 300 to the target discharge capacity and the target temperature of the evaporator and control the compressor 300 according to the current discharge capacity or By continuously monitoring the change in evaporator temperature, the calculated ECV duty value is output so that the difference between the target discharge capacity or evaporator target temperature and the current discharge capacity or evaporator temperature is minimized, and such calculation and output are repeated continuously. .

As described above, the main controller 120 continuously calculates the target discharge capacity and the evaporator target temperature through the target temperature set inside the vehicle, the current temperature inside the vehicle, the refrigerant pressure information, and the like. Feedback control of the refrigerant discharge capacity and the evaporator temperature of the compressor (300).

In addition, the air conditioner control unit 100 is provided with an ECV driver 160 as described above. The ECV driver 160 controls the refrigerant discharge capacity of the compressor 300, and the control of the compressor discharge capacity of the air conditioner control unit 100 controls the ECV duty to adjust the swash plate 48 of the compressor 300. By adjusting the inclination angle of the control panel, and adjusting the angle of the swash plate 48 by adjusting the opening degree of the flow path between the discharge chamber 33 and the crank chamber 21 to adjust the discharge capacity of the compressor 300. do. Here, the ECV 320 corresponds to the control valve 35 as shown in FIG. 1.

Hereinafter, the ECV duty control method of the air conditioning apparatus for controlling the driving of the air conditioning apparatus including the compressor configured as described above will be described.

4 is a graph illustrating an ECV duty adjusting method of the air conditioning apparatus according to the first embodiment of the present invention, and FIG. 5 is a graph illustrating an ECV duty adjusting method of the air conditioning apparatus according to the second embodiment of the present invention. 6 is a graph illustrating an ECV duty adjusting method of an air conditioning apparatus according to a third embodiment of the present invention.

As shown in FIG. 4, first, when the vehicle is driven at a stop or idle state of low speed, or when the air conditioner is operated at a high wind volume, the evaporator temperature becomes higher than the evaporator target temperature.

Therefore, the main controller 120 that detects this increases the ECV duty. And when the ECV duty reaches a preset threshold (eg 85%), it no longer increases the ECV duty.

However, if the evaporator temperature does not fall for more than a certain time t _s from when the ECV duty reaches the threshold, or if the actual temperature of the evaporator does not reach the evaporator target temperature, the ECV duty is increased to 100%. In this case, it is not necessary to set the ECV duty to increase by 100% from a threshold value, and a maximum value having a higher duty ratio may be set separately from the threshold value. That is, setting the threshold value to 85% and the maximum value to 100% is just one embodiment. In this case, the predetermined time t _s is a preset value.

As the ECV duty is increased to the maximum value, the refrigerant discharge capacity of the compressor increases to decrease the temperature of the evaporator. Accordingly, when the temperature of the evaporator approaches the evaporator target temperature, the ECV that is adjusted to the maximum value is adjusted. Lower the duty back to the threshold. Alternatively, the ECV duty may be lowered according to the ECV duty value calculated by the ECV duty calculation method as described above.

The evaporator temperature thus approaches the evaporator target temperature and maintains that state. Here, when the vehicle is driven again or the high air volume of the air conditioner is released, a more stable ECV duty is output to maintain the evaporator temperature near the evaporator target temperature.

According to the control method of the automotive air conditioner according to the first embodiment of the present invention as described above, the evaporator temperature does not decrease even though a predetermined time ts has elapsed since the ECV duty reaches a preset threshold. Otherwise, if the evaporator target temperature is not reached, the ECV duty is adjusted to its maximum value and the evaporator temperature begins to fall with the ECV duty adjusted to its maximum value, or when the evaporator target temperature is reached, the ECV duty is lowered again. In this way, the air conditioning system is controlled.

That is, in the graph, the air conditioner is controlled according to the ECV duty value calculated by the method described above until the ECV duty reaches the threshold value, but when the ECV duty reaches the threshold value, the ECV duty is determined from there. The ECV duty is forced to a threshold or maximum until it drops again.

Meanwhile, as shown in FIG. 5, when the evaporator temperature is higher than the evaporator target temperature and continuously rises, the ECV duty is also increased accordingly. The air conditioner is controlled according to the calculated ECV duty value.

Even though the ECV duty continues to increase, if the evaporator temperature continues to increase and the ECV duty reaches a threshold (eg 85%), the main controller 120 controls the ECV duty according to the calculated value. Instead, it is forced to the maximum value (for example, 100%).

If the ECV duty value calculated as the evaporator temperature approaches the evaporator target temperature is lower than the threshold value, the ECV duty is lowered to the calculated ECV duty value. That is, the main controller 120 continuously calculates the general ECV duty calculation value using the evaporator target temperature and the evaporator temperature even in a state in which the ECV duty is forcibly controlled to the maximum value. When the calculated value falls below the threshold value, that is, when the calculated ECV duty falls to the threshold value, the ECV duty that has been adjusted to the maximum value is lowered to the threshold value, and after that, the main controller 120 again returns to the main controller 120. The ECV duty is adjusted according to the value calculated by

In addition, in the air conditioner control method according to the third embodiment of the present invention, as shown in Figure 6, the main controller 120 controls the compressor 300 according to the calculated ECV duty value.

When the evaporator temperature does not fall even when the ECV duty calculated by the main controller 120 continuously rises above a threshold and reaches a maximum value, the ECV duty is maintained at the maximum value.

When the evaporator temperature starts to fall or the calculated ECV duty value starts to fall, the main controller 120 drops the ECV duty to a threshold value. After that, when the ECV duty calculated by the main controller 120 falls below a threshold value, the forced control of the ECV duty is terminated, and the compressor 300 is controlled according to the ECV duty value calculated by the main controller 120. Done.

In this case, the ECV duty value calculated by the main controller 120 is referred to as an 'ECV calculation duty' and is used to drive the compressor 300 by actually outputting the main controller 120 to the ECV driver 160. The ECV duty value to be referred to as 'ECV control duty' will be described in the claims.

In addition, as another embodiment of the present invention, the first of the present invention as shown in Figs. The ECV duty may be controlled according to the third embodiment, and when the current value applied is equal to or greater than a preset value, the ECV duty value may be adjusted according to a conventional method. To this end, the current value transmitted to the ECV may be measured separately and transmitted to the main controller 120.

The rights of the present invention are not limited to the embodiments described above, but are defined by the claims, and those skilled in the art can make various modifications and adaptations within the scope of the claims. It is self-evident.

The present invention relates to a vehicle air conditioner, and more particularly, to control the vehicle air conditioner that can provide more excellent air conditioning performance by increasing the ECV duty for controlling the compressor of the car air conditioner to the maximum value according to the air conditioning environment It is about a method. According to the present invention, when the evaporator temperature does not reach the target temperature in a short time or the current value delivered to the ECV is less than the set value, the ECV duty output is increased to improve the cooling performance of the air conditioner.

1 is a graph showing a method for adjusting the ECV duty in the air conditioner control method according to the prior art.

2 is a cross-sectional view showing the internal configuration of a variable displacement swash plate compressor.

Figure 3 is a block diagram showing the configuration of the air conditioner control unit and the engine control system provided in the present invention.

4 is a graph showing an ECV duty adjusting method according to the first embodiment of the present invention.

5 is a graph illustrating an ECV duty adjusting method according to a second embodiment of the present invention.

6 is a graph illustrating an ECV duty adjusting method according to a third embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

100: air conditioner control unit 120: main controller

140: memory 160: ECV driver

200: detector 300: compressor

320: ECV

Claims (6)

(A) calculating an ECV calculation duty for adjusting the refrigerant discharge capacity of the compressor of the vehicle air conditioner according to the evaporator temperature and the evaporator target temperature; (B) controlling the compressor by outputting the ECV calculation duty calculated in step (A) as an ECV control duty; (C) controlling the compressor by increasing the ECV control duty to a maximum value when the ECV operation duty rises to reach a threshold value during the step (B); And And (D) controlling a compressor using the ECV operation duty as the ECV control duty when a predetermined condition is satisfied in step (C). The method of claim 1, In the step (D), When the predetermined condition is satisfied in the step (C), the ECV control duty is rapidly lowered from the maximum value to the threshold value, and then the compressor is controlled by using the ECV calculation duty as the ECV control duty. Control method of air conditioner for water. The method of claim 1, Step (C) is, (C11) monitoring the increase or decrease of the evaporator temperature while maintaining the ECV control duty at a threshold when the ECV compute duty reaches a threshold; And (C12) if the evaporator temperature does not decrease for more than a predetermined time, increasing the ECV control duty from the threshold value to the maximum value, thereby controlling the compressor while maintaining the ECV control duty at the maximum value. Control method of a vehicle air conditioner, characterized in that. The method of claim 1, Step (C) is, (C21) when the ECV calculation duty reaches a threshold, ramping up the ECV control duty to a maximum value; And (C22) controlling the compressor while maintaining the ECV control duty to a maximum value. The method of claim 1, Step (C) is, (C31) controlling the compressor according to the ECV control duty while constantly raising the ECV control duty from the threshold to the maximum value when the ECV calculation duty reaches a threshold; And (C31) controlling the compressor while maintaining the ECV control duty at the maximum value when the ECV control duty reaches the maximum value. The method according to any one of claims 3 to 5, In the step (D), the predetermined condition is, And the ECV calculation duty falls below the threshold or the evaporator temperature begins to fall.

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