KR-20260062837-A - Air conditioning system for vehicle and control method thereof

KR20260062837AKR 20260062837 AKR20260062837 AKR 20260062837AKR-20260062837-A

Abstract

The present invention relates to an air conditioning system for a vehicle and a method for controlling the same. The air conditioning system for a vehicle may include an ambient temperature sensor used for detecting ambient temperature; an evaporator temperature sensor used for detecting evaporator temperature; and a controller. The controller is configured to set an upper limit for the evaporator target temperature as a first upper limit value, acquire the evaporator target temperature, determine whether to limit the evaporator target temperature by applying the first upper limit value according to the detected ambient temperature, the evaporator temperature, and the acquired evaporator target temperature, and if the evaporator target temperature is limited by applying the first upper limit value, change the upper limit for the evaporator target temperature according to whether a periodic fluctuation has occurred in the evaporator temperature, and limit the evaporator target temperature by applying the changed upper limit for the evaporator target temperature.

Inventors

탕쉬에샨
푸하오
호우칭동
짜이시아오루에이
추린팽
샤오징징
정태훈
푸딩위엔

Assignees

현대자동차주식회사
기아 주식회사

Dates

Publication Date: 20260507
Application Date: 20251002
Priority Date: 20241029

Claims (20)

In the vehicle's air conditioning system, It includes an ambient temperature sensor, an evaporator temperature sensor, and a controller, The above ambient temperature sensor is used for detecting ambient temperature; The above evaporator temperature sensor is used for detecting the evaporator temperature; The above controller is, Set the upper limit of the evaporator target temperature to the first upper limit value; Achieve the target evaporator temperature according to the heat load of the air conditioning system; Determining whether to limit the evaporator target temperature by applying a first upper limit value based on the detected ambient temperature, evaporator temperature, and acquired evaporator target temperature; An air conditioning system for a vehicle configured to limit the evaporator target temperature by applying a first upper limit value, change the upper limit of the evaporator target temperature depending on whether periodic fluctuations have occurred in the evaporator temperature, and limit the evaporator target temperature by applying the changed upper limit of the evaporator target temperature.
In paragraph 1, The above controller is, If the detected ambient temperature is lower than a first predetermined temperature, the upper limit of the evaporator target temperature is set to a second upper limit value, and the evaporator target temperature is limited by applying the second upper limit value. The above second upper limit is smaller than the above first upper limit, in a vehicle air conditioning system.
In paragraph 2, The above controller is, If the detected ambient temperature is higher than or equal to a first predetermined temperature, determine whether the detected evaporator temperature is lower than or equal to a second predetermined temperature and whether the acquired evaporator target temperature is higher than a third predetermined temperature; A vehicle air conditioning system configured to limit the evaporator target temperature by applying a first upper limit value when it is determined that the detected evaporator temperature is lower than or equal to a second predetermined temperature and the acquired evaporator target temperature is higher than a third predetermined temperature.
In paragraph 3, The above controller is, When limiting the evaporator target temperature by applying a first upper limit, the evaporator temperature is monitored for a predetermined period of time to determine whether periodic fluctuations have occurred in the evaporator temperature; An air conditioning system for a vehicle configured such that when it is determined that a periodic fluctuation has occurred in the evaporator temperature, the smaller value between the upper limit of the evaporator target temperature and the evaporator target temperature is reduced by a first predetermined value to become the upper limit of the evaporator target temperature.
In paragraph 4, The above controller is, If it is determined that no periodic fluctuation has occurred in the evaporator temperature, determine whether the detected evaporator temperature is lower than or equal to the fourth predetermined temperature; A vehicle air conditioning system configured to continue detecting the evaporator temperature until the detected evaporator temperature is lower than or equal to the fourth predetermined temperature when it is determined that the evaporator temperature is higher than the fourth predetermined temperature.
In paragraph 5, The above controller is, An air conditioning system for a vehicle configured such that when the evaporator temperature is determined to be lower than or equal to a fourth predetermined temperature, the smaller value between the upper limit of the evaporator target temperature and the evaporator target temperature is increased by a second predetermined value to become the upper limit of the evaporator target temperature.
In paragraph 4 or 6, The above controller is, A vehicle air conditioning system configured to determine whether to limit the evaporator target temperature by applying the changed evaporator target temperature upper limit according to the magnitude of the changed evaporator target temperature upper limit when the evaporator target temperature upper limit is increased or decreased.
In Paragraph 7, The above controller is, If it is determined that the modified evaporator target temperature upper limit is greater than or equal to the second upper limit and less than or equal to the first upper limit, the modified evaporator target temperature upper limit is applied to limit the evaporator target temperature; If it is determined that the modified evaporator target temperature upper limit is smaller than the second upper limit value, the evaporator target temperature is limited by applying the second upper limit value; A vehicle air conditioning system configured to limit the evaporator target temperature by applying the first upper limit value when it is determined that the changed evaporator target temperature upper limit is greater than the first upper limit value.
In paragraph 4, The above controller is, If the maximum value of the evaporator temperature within a predetermined time is monitored to be less than the 5th predetermined temperature or the change value of the evaporator temperature is less than the 6th predetermined temperature, it is determined that no periodic fluctuation has occurred in the evaporator temperature; If the maximum value of the evaporator temperature within a predetermined time is monitored to be greater than or equal to the 5th predetermined temperature and the change value of the evaporator temperature is greater than or equal to the 6th predetermined temperature, determine whether the compressor has stopped operating; A vehicle air conditioning system configured to determine that no periodic fluctuations in the evaporator temperature have occurred when it is determined that a compressor shutdown has occurred.
In Paragraph 9, The above controller is, If it is determined that no compressor shutdown has occurred, determine whether an event affecting compressor power occurs, including a change in engine rotational speed, a change in the blower speed of the air conditioning system, a change in vehicle speed, and a change in the ratio of internal to external circulation of the air conditioning system; If it is determined that an event affecting compressor power has occurred, determine whether the sum of the influencing factors of the event affecting the compressor is greater than or equal to a third predetermined value; If the sum of the influencing factors of the event affecting the generated compressor power is determined to be greater than or equal to a third predetermined value, it is determined that a periodic fluctuation has occurred in the evaporator temperature; An air conditioning system for a vehicle configured to determine that no periodic fluctuation in the evaporator temperature has occurred if the sum of the influencing factors of an event affecting the generated compressor power is determined to be smaller than a third predetermined value.
In a method for controlling a vehicle's air conditioning system, Step of setting the upper limit of the evaporator target temperature to the first upper limit value; A step of obtaining a target evaporator temperature according to the heat load of the air conditioning system; A step of detecting the ambient temperature through an ambient temperature sensor and detecting the evaporator temperature through an evaporator temperature sensor; A step of determining whether to limit the evaporator target temperature by applying a first upper limit value according to the detected ambient temperature, evaporator temperature, and acquired evaporator target temperature; When limiting the evaporator target temperature by applying a first upper limit value, a step of changing the upper limit of the evaporator target temperature depending on whether periodic fluctuations have occurred in the evaporator temperature; and A step of limiting the evaporator target temperature by applying a modified evaporator target temperature upper limit; A method for controlling a vehicle's air conditioning system, including
In Paragraph 11, If the detected ambient temperature is lower than a first predetermined temperature, the step of setting the upper limit of the evaporator target temperature to a second upper limit value; and A step of limiting the evaporator target temperature by applying a second upper limit value; Includes more, A method for controlling a vehicle's air conditioning system, wherein the second upper limit value is smaller than the first upper limit value.
In Paragraph 12, A step of determining whether the detected ambient temperature is lower than or equal to the second predetermined temperature and whether the acquired evaporator target temperature is higher than the third predetermined temperature, if the detected ambient temperature is higher than or equal to the first predetermined temperature; If it is determined that the detected evaporator temperature is lower than or equal to a second predetermined temperature and the acquired evaporator target temperature is higher than a third predetermined temperature, a step of limiting the evaporator target temperature by applying a first upper limit value; A method for controlling a vehicle's air conditioning system, further comprising
In Paragraph 13, When limiting the evaporator target temperature by applying a first upper limit value, a step of monitoring the evaporator temperature for a predetermined period of time to determine whether periodic fluctuations have occurred in the evaporator temperature; and If it is determined that periodic fluctuations have occurred in the evaporator temperature, the step of reducing the smaller value between the upper limit of the evaporator target temperature and the evaporator target temperature by a first predetermined value to set the upper limit of the evaporator target temperature; A method for controlling a vehicle's air conditioning system, further comprising
In Paragraph 14, If it is determined that no periodic fluctuation has occurred in the evaporator temperature, a step of determining whether the detected evaporator temperature is lower than or equal to a fourth predetermined temperature; and If it is determined that the evaporator temperature is higher than the fourth predetermined temperature, the step of continuously sensing the evaporator temperature until the sensed evaporator temperature is lower than or equal to the fourth predetermined temperature; A method for controlling a vehicle's air conditioning system, further comprising
In paragraph 15, A method for controlling an air conditioning system of a vehicle, further comprising the step of, when the evaporator temperature is determined to be lower than or equal to a fourth predetermined temperature, increasing the smaller value between the upper limit of the evaporator target temperature and the evaporator target temperature by a second predetermined value to set the upper limit of the evaporator target temperature.
In paragraph 14 or 16, A method for controlling an air conditioning system of a vehicle, further comprising the step of determining whether to limit the evaporator target temperature by applying the changed evaporator target temperature upper limit according to the magnitude of the changed evaporator target temperature upper limit when the evaporator target temperature upper limit is increased or decreased.
In Paragraph 17, If it is determined that the modified evaporator target temperature upper limit is greater than or equal to the second upper limit value and less than or equal to the first upper limit value, a step of limiting the evaporator target temperature by applying the modified evaporator target temperature upper limit; If it is determined that the modified evaporator target temperature upper limit is smaller than the second upper limit value, the step of limiting the evaporator target temperature by applying the second upper limit value; and If it is determined that the modified evaporator target temperature upper limit is greater than the first upper limit value, the step of limiting the evaporator target temperature by applying the first upper limit value; A method for controlling a vehicle's air conditioning system, further comprising
In Paragraph 14, A step of determining that no periodic fluctuation has occurred in the evaporator temperature if the maximum value of the evaporator temperature within a predetermined time is monitored to be smaller than a fifth predetermined temperature or the change value of the evaporator temperature is smaller than a sixth predetermined temperature; A step of determining whether the compressor has stopped operating if the maximum value of the evaporator temperature within a predetermined time is monitored to be greater than or equal to a fifth predetermined temperature and the change value of the evaporator temperature is greater than or equal to a sixth predetermined temperature; and A step of determining that no periodic fluctuations in the evaporator temperature have occurred when it is determined that the compressor has stopped operating; A method for controlling a vehicle's air conditioning system, further comprising
In Paragraph 19, If it is determined that no interruption of compressor operation has occurred, a step of determining whether an event affecting compressor power occurs, including a change in engine rotational speed, a change in the blower speed of the air conditioning system, a change in vehicle speed, and a change in the ratio of internal to external circulation of the air conditioning system; If it is determined that an event affecting compressor power has occurred, a step of determining whether the sum of the influencing factors of the event affecting the compressor is greater than or equal to a third predetermined value; A step of determining that no periodic fluctuation has occurred in the evaporator temperature if the total sum of influencing factors causing an event affecting the generated compressor power is determined to be greater than or equal to a third predetermined value; and A step of determining that no periodic fluctuation has occurred in the evaporator temperature if the sum of the influencing factors of the event affecting the generated compressor power is determined to be smaller than a third predetermined value; A method for controlling a vehicle's air conditioning system, further comprising

Description

Air conditioning system for vehicle and control method thereof The present invention relates to a vehicle air conditioning system and a method for controlling the same, and more specifically, to a vehicle air conditioning system and a method for controlling the same that can reduce energy consumption while ensuring the cooling performance of the air conditioning system. As is known, a vehicle's air conditioning system achieves cooling by driving a compressor with the engine. The greater the power output from the engine to drive the compressor, the stronger the cooling performance of the air conditioning system. However, if the cooling performance of the air conditioning system is excessive, unnecessary fuel consumption by the engine increases, and the vehicle's fuel efficiency decreases. To prevent excessive cooling performance of the air conditioning system, the engine power required to drive the compressor can be reduced by increasing the evaporator temperature (ET). The evaporator temperature is controlled by the evaporator target temperature (ETT), and the evaporator target temperature is limited by the evaporator target temperature top limit (ETTT). Therefore, the engine power required to drive the compressor can be reduced by increasing the evaporator target temperature top limit. Here, the evaporator temperature refers to the actual temperature at which the refrigerant evaporates, and it can be detected through an evaporator temperature sensor installed on the evaporator. The controller of the HVAC system can calculate the target evaporator temperature based on the system's heat load and controls the evaporator temperature according to the calculated target temperature, thereby ensuring that the evaporator temperature approaches the target temperature infinitely closely. However, the target evaporator temperature is merely a theoretical value calculated based on the heat load. If the heat load is low, the calculated target evaporator temperature may be high, and the HVAC system cannot control the evaporator temperature by applying the aforementioned target temperature. Therefore, an upper limit for the target evaporator temperature is additionally set to restrict the upper limit of the target temperature. If the calculated target evaporator temperature is higher than the upper limit, the evaporator temperature is controlled by setting the upper limit as the target temperature. Conventionally, the upper limit of the target temperature of the evaporator in a vehicle's air conditioning system was set to 4°C. If the upper limit of the target temperature of the evaporator is set higher than 4°C, it affects the stable operation of the air conditioning system, and periodic fluctuations occur in the evaporator temperature of the refrigerant in the air conditioning system, which affects the cooling effect of the air conditioning system and can reduce the ride comfort of the vehicle occupants. Therefore, it is necessary to present a vehicle air conditioning system and a control method thereof that can reduce energy consumption while ensuring the cooling performance of the air conditioning system. The matters described in this background technology section are written to enhance understanding of the background of the invention and may include matters that are not prior art already known to those skilled in the art to which this technology belongs. The objectives, features, and advantages of the present invention will be explained in detail with reference to the drawings below so that they may be more clearly and easily understood. FIG. 1 is a schematic diagram showing a vehicle air conditioning system according to an exemplary embodiment of the present invention. FIGS. 2a and 2b are flowcharts illustrating a control method for a vehicle air conditioning system according to an exemplary embodiment of the present invention. FIG. 3 is a flowchart illustrating a method for determining periodic fluctuations in evaporator temperature according to an exemplary embodiment of the present invention. The terms “vehicle,” “of a vehicle,” or other similar terms used herein should be understood to generally include mobility vehicles such as sports utility vehicles (SUVs), buses, trucks, and various commercial vehicles including passenger cars, vessels including various boats or ships, aircraft, etc., and to include hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles, and other alternative fuel (fuel derived from resources other than petroleum) vehicles. Although exemplary embodiments have been described as performing an exemplary process using multiple units, it should be understood that the exemplary process may be performed by one or more modules. It should also be understood that the term “controller” refers to a hardware device comprising memory and a processor. The memory is configured to store modules, and the processor is configured specifically to execute said modules to co