KR20220148410A - Apparatus for determining fault of vehicle air conditioning system and method thereof - Google Patents

Abstract

The present invention relates to a device for determining a disorder in an air conditioning system for a vehicle and a method thereof. According to the present invention, the device comprises: a data reception unit receiving the information of pressure and temperature from sensors, respectively installed in a low-pressure line connected to an entrance side of an electric compressor included in the air conditioning system of a vehicle and a high-pressure line connected to an exit side thereof; a first determination unit determining whether a first reference time has passed from the point of time when the electric compressor has started operation, and when it is determined that the time has passed, calculating the difference in pressure between the low-pressure line and the high-pressure line, and determining if the calculated difference in pressure is equal to or below a reference pressure or not; a second determination unit calculating, when the difference in pressure is above the reference pressure, the difference in temperature between the low-pressure line and the high-pressure line and determining whether the calculated difference in temperature is equal to or below a reference temperature or not; and a control unit driving or stopping the operation of the electric compressor in accordance with the results of determination of the first determination unit and the second determination unit, comparing the number of times of stopping the operation of the electric compressor with the reference number of times, and determining whether a disorder has occurred in the electric compressor. As such, according to the present invention, even when there is an insignificant disorder in a refrigerant line connected to the entrance or the exit of an electric compressor installed in an air conditioning system of a vehicle, the operation of the electric compressor can be stopped, thereby preventing damage which can spread to the whole system.

Description

Apparatus for determining fault of vehicle air conditioning system and method thereof

The present invention relates to a failure determination apparatus and method for an air conditioning system for a vehicle, which measure the outlet pressure and inlet pressure and temperature of an electric compressor installed in the vehicle air conditioning system, respectively, and measure the difference in pressure or temperature It relates to a failure determination device and method for determining whether a refrigerant line connected to an electric compressor has failed using the method.

In general, automobiles are provided with an air conditioner that appropriately cools the interior of the vehicle in summer to maintain a comfortable indoor temperature of the vehicle. The air conditioner uses the latent heat of a refrigerant that is compressed by the rotational force of an engine and circulates, and is composed of an evaporator, a compressor, a condenser, an expansion valve, and the like.

Eco-friendly vehicles, such as hybrid vehicles/electric vehicles/fuel cell vehicles, are vehicles that run on electric energy based on charging power or generated power.

Among the above components, the compressor compresses low-temperature/low-pressure gaseous refrigerant from an evaporator into high-temperature, high-pressure gaseous refrigerant, and then sends it to the condenser.

At this time, when problems such as blockage due to foreign substances, valve failure, compressor sticking, etc. occur in the refrigerant line connected to the compressor, a high pressure higher than the reference value is formed in the high pressure side line, and a low pressure lower than the reference value is formed in the low pressure side line This happens. Also, a phenomenon in which the refrigerant temperature is increased according to the pressure occurs.

Therefore, in the prior art, a reference value for the pressure value in the high pressure side line and the pressure value in the low pressure side line are set, and when it is determined that the pressure is higher or lower than the set reference value, it is determined that a failure has occurred in the refrigerant line.

However, in the early stage of the failure, the refrigerant pressure or the refrigerant pressure temperature is not rapidly increased or decreased, and thus, there is a problem in that it is not possible to determine whether there is a failure.

If this phenomenon intensifies and a sudden change in refrigerant pressure or refrigerant pressure temperature occurs, the refrigerant line is seriously damaged and all parts of the refrigerant line system are damaged. may be replaced.

In particular, in the case of an electric vehicle, since high voltage is applied, if the operation of the compressor is not stopped at the initial stage of failure, a problem may occur that may damage not only the refrigerant line but also the components of the high voltage system.

The technology that is the background of the present invention is disclosed in Korean Patent Registration No. 10-0580523 (published on May 15, 2006).

The technical problem to be achieved by the present invention is to measure the outlet pressure and the inlet pressure and temperature of an electric compressor installed in a vehicle air conditioning system, respectively, and use the difference in the measured pressure or temperature to break the refrigerant line connected to the electric compressor An object of the present invention is to provide a failure determination device and method for determining whether or not there is a problem.

According to an embodiment of the present invention for achieving this technical problem, in the failure determination device for an air conditioning system for a vehicle, a low pressure line connected to the inlet side of the electric compressor included in the vehicle air conditioning system and a high pressure line connected to the outlet side are respectively connected A data receiving unit for receiving pressure and temperature from the installed sensor, determining whether a first reference time has elapsed from the time when the electric compressor is operated, and if it is determined that it has elapsed, the A first determination unit that calculates a pressure difference and determines whether the calculated pressure difference is equal to or less than a reference pressure, if the pressure difference is greater than a reference pressure, calculates a temperature difference between the temperature of the low pressure line and the temperature of the high pressure line, and calculates A second determination unit that determines whether the temperature difference is equal to or less than the reference temperature, and driving or stopping the operation of the electric compressor according to the determination result of the first determination unit and the second determination unit, and stopping the operation of the electric compressor A control unit for determining whether a failure of the electric compressor has occurred by comparing the number of times and the reference number of times.

The controller may stop the operation of the electric compressor when the pressure difference between the pressure of the low-pressure line and the pressure of the high-pressure line is maintained for a second reference time of less than or equal to the reference pressure.

The control unit, when the pressure difference is greater than the reference pressure, and the temperature difference between the temperature of the low-pressure line and the temperature of the high-pressure line is maintained for a second reference time or less, the operation of the electric compressor is stopped, and the When the pressure difference is greater than the reference pressure, and the temperature difference between the temperature of the low pressure line and the temperature of the high pressure line is greater than the reference temperature, the operation of the electric compressor may be driven.

When the control unit stops the operation of the electric compressor according to the determination result obtained by using the first determination unit or the second determination unit after the time when the vehicle is started, the operation of the electric compressor until the vehicle is turned off is maintained in a stopped state, and when the engine is turned off and restarted after driving is completed, the operation of the electric compressor is driven, and the pressure difference and temperature difference between the high-pressure line and the low-pressure line connected to the electric compressor are recalculated and the It can be judged whether the electric compressor is operated or not.

The control unit accumulates the number of times the operation of the electric compressor is stopped, and if the accumulated number is greater than or equal to the reference number of times, the controller maintains the electric compressor in a non-operational state even if the vehicle is restarted, and sends a failure signal to the air conditioning system of the vehicle can be forwarded to

In addition, according to an embodiment of the present invention, in the failure determination method using the failure determination device, the pressure from the sensor installed in the low pressure line connected to the inlet side and the high pressure line connected to the outlet side of the electric compressor included in the vehicle air conditioning system, respectively and receiving the temperature, determining whether a first reference time has elapsed from the time when the electric compressor is operated, and calculating the pressure difference between the pressure of the low pressure line and the pressure of the high pressure line when it is determined that the time has elapsed, , determining whether the calculated pressure difference is equal to or less than the reference pressure, if the pressure difference is greater than the reference pressure, calculating the temperature difference between the temperature of the low pressure line and the temperature of the high pressure line, and determining whether the calculated temperature difference is less than or equal to the reference temperature Determining, and driving or stopping the operation of the electric compressor in response to the determination result, and comparing the number of times of stopping the operation of the electric compressor with a reference number of times to determine whether a failure of the electric compressor occurs include

As described above, according to the present invention, even when the refrigerant line connected to the inlet or outlet of the electric compressor installed in the vehicle air conditioning system has insufficient failure, the operation of the electric compressor is stopped to prevent damage that may change to the entire system.

1 is a diagram schematically illustrating a configuration of an air conditioning system for a vehicle.
2 is a configuration diagram for explaining the configuration of a failure determination device according to an embodiment of the present invention.
3 is a flowchart illustrating a failure determination method of an air conditioning system for a vehicle using the failure determination apparatus according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art can easily carry out the present invention. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

Throughout the specification, when a part "includes" a certain component, it means that other components may be further included, rather than excluding other components, unless otherwise stated.

Then, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those of ordinary skill in the art to which the present invention pertains can easily implement them.

First, a configuration of an air conditioning system for a vehicle will be briefly described below.

1 is a diagram schematically illustrating a configuration of an air conditioning system for a vehicle.

As shown in FIG. 1 , the vehicle air conditioning system 100 includes an electric compressor 110 , a condenser 120 , an expansion valve 130 , and an evaporator 140 .

First, the motor-driven compressor 110 compresses and delivers the introduced refrigerant, and the high-pressure refrigerant gas delivered from the motor-driven compressor 110 is delivered to the condenser 120 through a high-pressure line.

Then, the condenser 120 uses ambient air to cool the high-temperature refrigerant gas to a liquefied state, and the cooled liquid refrigerant is transferred to the evaporator 140 through the expansion valve 130 .

The evaporator 140 cools the air discharged into the room by absorbing heat by the latent heat of evaporation of the refrigerant by heat-exchanging the low-pressure liquid refrigerant throttled by the expansion valve 130 with air blown into the vehicle interior and evaporating.

Hereinafter, the failure determination device 200 for determining whether the vehicle air conditioning system 100 according to the embodiment of the present invention has a failure will be described in more detail with reference to FIG. 2 .

2 is a configuration diagram for explaining the configuration of the failure determination apparatus 200 according to an embodiment of the present invention.

As shown in FIG. 2 , the failure determination apparatus 200 according to an embodiment of the present invention includes a data receiving unit 210 , a first determining unit 220 , a second determining unit 230 , and a control unit 240 . .

First, the data receiving unit 210 receives data on pressure and temperature from sensors (not shown) respectively installed in the low pressure line connected to the inlet side and the high pressure line connected to the outlet side of the electric compressor 110 .

Then, when the electric compressor 110 is operated after the time when the vehicle is started, the first determination unit 220 determines whether a first reference time has elapsed from the time when the electric compressor 110 is operated. judge When it is determined that the first reference time has elapsed, the first determination unit 220 calculates a pressure difference using pressures respectively received from the sensor installed in the low pressure line and the sensor installed in the high pressure line. In addition, the first determination unit 120 determines whether the calculated pressure difference is equal to or less than a reference pressure, and whether the state of being equal to or less than the reference pressure is maintained for a second reference time.

The second determination unit 230 calculates a temperature difference using the temperatures respectively received from the sensor installed in the low-pressure line and the sensor installed in the high-pressure line, and determines a state in which the calculated temperature difference is less than or equal to a reference temperature and less than or equal to the reference temperature. It is determined whether or not it is maintained for the reference time.

In this case, the second determination unit 230 determines only when the difference between the pressure measured in the low pressure line and the pressure measured in the high pressure line is greater than the reference pressure as a result of the determination by the first determination unit 220 .

Finally, the control unit 240 stops or maintains the operation of the electric compressor 110 according to a result determined by the first determination unit 220 or the second determination unit 230 .

In other words, when it is determined that the pressure difference between the pressure of the low-pressure line and the pressure of the high-pressure line is equal to or less than the reference pressure for the second reference time, the control unit 240 stops the operation of the electric compressor 110 . .

In addition, when it is determined that the pressure difference is greater than the reference pressure and the temperature difference between the temperature of the low-pressure line and the temperature of the high-pressure line is maintained for the second reference time or less, the controller 240 controls the electric compressor 110 ) to stop working.

In this case, the control unit 240 maintains the operation of the motor-driven compressor 110 in a stopped state until the vehicle is turned off.

And, when the vehicle is restarted, the control unit 240 re-determines whether the operation of the electric compressor 110 is driven, and as a result of the re-determination, when the operation of the electric compressor 110 is stopped again, stop Accumulate the number of times And when the number of stops corresponds to the preset number, the control unit 240 determines that a failure has occurred in the electric compressor 110 and transmits a failure occurrence signal to the vehicle air conditioning system 100 .

Hereinafter, a failure determination method for the vehicle air conditioning system 100 using the failure determination apparatus 200 according to an embodiment of the present invention will be described in more detail with reference to FIG. 3 .

3 is a flowchart illustrating a failure determination method of an air conditioning system for a vehicle using the failure determination apparatus according to an embodiment of the present invention.

3, the failure determination device 200 according to an embodiment of the present invention receives data on pressure and temperature from sensors installed in the low-pressure line and the high-pressure line connected to the electric compressor 110 ( S310).

In other words, the data receiving unit 210 receives pressure from sensors installed in the low pressure line connected to the inlet side and the high pressure line connected to the outlet side of the electric compressor 110 , respectively. In this case, the received pressure is a value measured after 10 seconds have elapsed from the time when the vehicle is started and the motor-driven compressor 110 is operated.

Next, the first determination unit 210 determines whether a difference between the pressure measured in the low pressure line and the pressure measured in the high pressure line is less than or equal to a reference pressure (S320).

When the refrigerant provided to the vehicle air conditioning system 100 flows normally, the deviation of the pressures measured in the low-pressure line and the high-pressure line connected to the electric compressor 110 is at least 3 kgf/cm 2 , and in the low-pressure line and the high-pressure line The deviation of each measured temperature appears to be at least 10°C or more.

On the other hand, when a serious failure occurs in the vehicle air conditioning system 100 , the pressure measured in the low-pressure line of the motor-driven compressor 110 is 0.1 kgf/cm 2 or less, and is measured in the high-pressure line of the motor-driven compressor 110 , respectively. The applied pressure is 30kgf/cm2 or more, and the temperature measured in the high-pressure line is 120℃ or more.

Accordingly, the failure determination apparatus 200 according to an embodiment of the present invention determines whether the vehicle air conditioning system 100 has a failure by using the symptoms appearing insufficiently to determine the reference pressure for the pressure difference between the low pressure line and the high pressure line. set And, the first determination unit 210 compares the pressure difference obtained by subtracting the pressure measured in the low pressure line from the pressure measured in the high pressure line with the set reference pressure, whether the obtained pressure difference is equal to or less than the reference pressure judge

For example, assuming that the reference pressure is 2 kgf/cm 2 , the first determination unit 210 calculates a pressure difference by subtracting the pressure measured in the low pressure line from the pressure measured in the high pressure line. In addition, the first determination unit 210 determines whether the calculated pressure difference is 2 kgf/cm 2 or less and maintains a state of 2 kgf/cm 2 or less for 5 seconds or more.

When it is determined in step S320 that the pressure difference measured in the high-pressure line and the low-pressure line is equal to or less than the reference pressure, and the state below the reference pressure is maintained for 5 seconds or more, the control unit 240 stops the operation of the electric compressor 110 . make it (S330).

In general, when the electric compressor 110 is driven in a state in which the failure occurring in the vehicle air conditioning system 100 is insufficient, the pressure measured in the low pressure line connected to the electric compressor 110 and the pressure measured in the high pressure line are different. may be output as small, or the pressure of the low-pressure line and the pressure of the high-pressure line may be output as inverted values.

Therefore, when the pressure difference measured in the low-pressure line and the high-pressure line is 2 kgf/cm 2 or less and the pressure difference 2 kgf/cm 2 or less is maintained for 5 seconds or more, the control unit 240 causes an abnormality in the vehicle air conditioning system 100 The driving of the electric compressor 110 is stopped until it is determined that the vehicle has been started and the engine is turned off.

On the other hand, when the pressure difference measured in the high-pressure line and the low-pressure line in step S320 is greater than the reference pressure, the second determination unit 230 uses the temperature measured in the low-pressure line and the high-pressure line connected to the electric compressor 110, respectively. to calculate a temperature difference, and determine whether the calculated temperature difference is equal to or less than a reference temperature (S340).

For example, assuming that the reference temperature is set to 2°C, the second determination unit 230 determines whether the calculated temperature difference is 2°C or less by subtracting the temperature measured in the low-pressure line from the temperature measured in the high-pressure line. do.

If the temperature difference calculated in step S340 is greater than the reference temperature, the control unit 240 maintains the operation of the electric compressor 110 .

On the other hand, when the temperature difference calculated in step S340 is equal to or less than the reference temperature and the temperature difference is maintained for 5 seconds or less, the control unit 240 stops the operation of the electric compressor 110 until the vehicle is turned off. make it

The control unit 240 according to the embodiment of the present invention is determined by using the pressure and temperature respectively measured in the low-temperature line and the high-temperature line connected to the electric compressor 110 after the time when the vehicle is started. The operation of the motor-driven compressor 110 is stopped or maintained.

After stopping the operation of the motor-driven compressor 110 according to the results determined in steps S320 and S340 and the vehicle is started again, the failure determination device 100 drives the operation of the motor-driven compressor 110 . to perform steps S310, S320, and S340 again.

And, when the operation of the electric compressor 110 is stopped again according to the result determined in step S320 or step S340, the control unit 240 accumulates the number of stops for the operation of the electric compressor 110, and the accumulated It is determined whether the number of stops is 3 or more (S350).

When the operation of the motor-driven compressor 100 is stopped once according to the determination result of steps S320 and S340, it cannot be determined whether a failure has actually occurred in the motor-driven compressor 100 or whether a temporary error has occurred. .

Therefore, the failure determination apparatus 100 according to an embodiment of the present invention repeatedly performs steps S310, S320, and S340, and accumulates the results determined in steps S320 and S340.

In addition, the control unit 240 determines whether the accumulated number of times of stopping the operation of the electric compressor 100 is three or more, which is a reference number. According to the embodiment of the present invention, it has been described that the reference number is set to three, but the reference number may be changed according to a design of those skilled in the art.

According to the determination result of step S350, if the number of times the operation of the motor-driven compressor 100 is stopped is three or more times, the control unit 240 determines that the low-pressure line or the high-pressure line connected to the motor-driven compressor 110 has insufficient failure. It is determined that the failure occurrence signal is transmitted to the vehicle air conditioning system 100 (S360).

In the case of an electric compressor, even if it is a minor failure, if left unattended, it can expand and damage parts connected to the refrigerant line. is transmitted to the vehicle air conditioning system 100 , so that the driver can recognize whether the vehicle air conditioning system 100 is faulty.

As described above, the failure determination device according to the present invention stops the operation of the electric compressor even when the refrigerant line connected to the inlet or outlet of the electric compressor installed in the vehicle air conditioning system is insufficient to prevent damage that can spread to the entire system. can

Although the present invention has been described with reference to the embodiment shown in the drawings, this is merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Accordingly, the true technical protection scope of the present invention should be defined by the technical spirit of the appended claims.

100: vehicle air conditioning system
110: electric compressor
120: condenser
130: expansion valve
140: evaporator
200: failure judgment device
210: data receiving unit
220: first judgment unit
230: second judgment unit
240: control unit

Claims (10)

In the failure determination device for an air conditioning system for a vehicle,
A data receiver for receiving pressure and temperature from sensors installed in the low-pressure line connected to the inlet side and the high-pressure line connected to the outlet side of the electric compressor included in the vehicle air conditioning system, respectively;
It is determined whether a first reference time has elapsed from the time when the electric compressor is operated, and when it is determined that it has elapsed, the pressure difference between the pressure of the low pressure line and the pressure of the high pressure line is calculated, and the calculated pressure difference is the reference pressure A first determination unit that determines whether or not
When the pressure difference is greater than the reference pressure, a second determination unit for calculating a temperature difference between the temperature of the low pressure line and the temperature of the high pressure line, and determining whether the calculated temperature difference is equal to or less than the reference temperature;
Driving or stopping the operation of the electric compressor according to the determination result of the first determination unit and the second determination unit, and comparing the number of times and a reference number of stopping the operation of the electric compressor to determine whether the failure of the electric compressor occurs Failure determination device including a control unit. According to claim 1,
The control unit is
When the pressure difference between the pressure of the low pressure line and the pressure of the high pressure line is maintained for a second reference time or less, the failure determination device stops the operation of the electric compressor. According to claim 1,
The control unit is
When the pressure difference is greater than the reference pressure and the temperature difference between the temperature of the low pressure line and the temperature of the high pressure line is maintained for a second reference time or less, the operation of the electric compressor is stopped,
When the pressure difference is greater than the reference pressure and the temperature difference between the temperature of the low pressure line and the temperature of the high pressure line is greater than the reference temperature, the failure determination device for driving the operation of the electric compressor. According to claim 1,
The control unit is
When the operation of the electric compressor is stopped according to the determination result obtained using the first determination unit or the second determination unit after the time when the vehicle is started, the operation of the electric compressor is stopped until the vehicle is turned off keep it as
When driving is completed and the engine is turned off and then restarted, the operation of the electric compressor is driven, and the pressure difference and temperature difference between the high-pressure line and the low-pressure line connected to the electric compressor are recalculated to determine whether the operation of the electric compressor is driven again. A failure judgment device that judges. 5. The method of claim 4,
The control unit is
Accumulate the number of times the operation of the electric compressor is stopped, and if the accumulated number is greater than or equal to the reference number, the electric compressor is maintained in a non-operational state even when the vehicle is restarted, and a failure occurrence signal is transmitted to the vehicle air conditioning system. Device. In the failure determination method using the failure determination device,
Receiving the pressure and temperature from sensors installed in the low pressure line connected to the inlet side and the high pressure line connected to the outlet side of the electric compressor included in the vehicle air conditioning system, respectively;
It is determined whether a first reference time has elapsed from the time when the electric compressor is operated, and when it is determined that it has elapsed, the pressure difference between the pressure of the low pressure line and the pressure of the high pressure line is calculated, and the calculated pressure difference is the reference pressure Step to determine whether or not
If the pressure difference is greater than the reference pressure, calculating a temperature difference between the temperature of the low-pressure line and the temperature of the high-pressure line, and determining whether the calculated temperature difference is equal to or less than a reference temperature;
A failure determination method comprising the step of driving or stopping the operation of the electric compressor in response to the determination result, and determining whether a failure of the electric compressor has occurred by comparing the number of times the operation of the electric compressor is stopped with a reference number of times. 7. The method of claim 6,
The step of determining whether a failure of the electric compressor occurs,
When the pressure difference between the pressure of the low pressure line and the pressure of the high pressure line is maintained for a second reference time or less, the failure determination method for stopping the operation of the electric compressor. 7. The method of claim 6,
The step of determining whether a failure of the electric compressor occurs,
When the pressure difference is greater than the reference pressure and the temperature difference between the temperature of the low pressure line and the temperature of the high pressure line is maintained for a second reference time or less, the operation of the electric compressor is stopped,
If the pressure difference is greater than the reference pressure, and the temperature difference between the temperature of the low pressure line and the temperature of the high pressure line is greater than the reference temperature, the failure determination method for driving the operation of the electric compressor. 7. The method of claim 6,
The step of determining whether a failure of the electric compressor occurs,
When the operation of the electric compressor is stopped according to the determination result obtained using the pressure difference and the temperature difference between the high-pressure line and the low-pressure line connected to the electric compressor after the time when the vehicle's engine is turned on, Keep the operation of the electric compressor in a stopped state,
When the driving is completed and the engine is turned off and then restarted, the operation of the electric compressor is driven, and the pressure difference and temperature difference between the high-pressure line and the low-pressure line connected to the electric compressor are recalculated to determine whether the operation of the electric compressor is driven. How to judge a failure. 10. The method of claim 9,
The step of determining whether a failure of the electric compressor occurs,
Failure to accumulate the number of times the operation of the electric compressor is stopped, and if the accumulated number is greater than or equal to the reference number, maintain the electric compressor in a non-operational state even if the vehicle is restarted, and transmit a failure signal to the air conditioning system of the vehicle How to judge.

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