System and method for controlling a compressor of a cold-start vehicle

Abstract

System (10) for controlling a compressor (13) of a cold-start vehicle, comprising the system: an internal combustion engine control unit (ECU, 11) which controls a fuel injection quantity corresponding to an internal combustion engine load and an opening amount of a throttle valve depending on a required torque which is necessary for an air conditioning (A / C), an operational information acquisition device (12) for acquiring operational information according to the driving condition of the cold start vehicle, a compressor (13) which generates pressure by means of a piston operation in a cylinder using the power of an internal combustion engine during the operation of the air conditioning system, an air conditioning relay (RL) which is switched on in response to an operating signal from the ECU when the air conditioning is in operation, and is switched off when the air conditioning is stopped, and a control device (17) which is connected to the ECU (11) and determines an internal combustion engine intake manifold vacuum stored in a brake booster with a value obtained by subtracting the internal combustion engine vacuum from the atmospheric pressure, which is detected by the operating information acquisition device (12), and wherein, if during operation of the air conditioning system a coolant temperature is lower than a predetermined temperature and an intake manifold vacuum is lower than a first threshold value (T1), a cold start intake manifold vacuum insufficient event is generated to reduce A / C operation of the compressor (13) according to an entry into a vacuum recovery mode.

Description

BACKGROUND OF THE INVENTION Area of ​​the invention

[0001] The present invention relates to a system and a method for controlling a compressor of a cold-start vehicle. In particular, the present invention relates to a system and a method for controlling a compressor of a cold-start vehicle, which is applied to an air conditioning system of a vehicle and which is variably controlled according to brake vacuum conditions during a cold start. Description of the related technology

[0002] If the brake vacuum stored in the brake booster is insufficient, the brake pedal will generally become hard, increasing the risk of an accident. To solve this problem, the system uses logic that restores brake vacuum by stopping the operation of auxiliary systems, such as the air conditioning (A / C), when brake vacuum is insufficient.

[0003] For example, a compressor used in an air conditioning system affects the internal combustion engine load during operation due to the nature of the engine's power output, and if the brake vacuum drops, a problem occurs during braking. Therefore, if the brake vacuum falls to a certain value or below, the required power output is ensured by stopping the air conditioning system (A / V OFF, hereinafter referred to as "A / C shutdown" or "A / C interruption").

[0004] Brake vacuum, as used here, refers to a value that is directly measured by installing a sensor in the brake booster based on the pressure stored within the actual brake booster. However, due to rising costs, many manufacturers use the difference between atmospheric pressure and intake manifold pressure (hereinafter referred to as "intake manifold vacuum") instead of installing the sensor on the actual brake booster.

[0005] Fig. Figure 1 is a concept diagram showing an A / C shutdown logic that uses a conventional vacuum from an intake manifold.

[0006] Referring to Fig. 1 is the A / C cut-off logic, which uses the conventional vacuum of the intake manifold, such that the A / C cut-off is generated if the vacuum falls below a certain value regardless of driving uphill, in highlands (e.g. above 1500 m) and in flatlands (lowlands) and other vehicle operating conditions meet the criteria.

[0007] The intake manifold vacuum, however, is not a measured value but a calculated one. Therefore, the difference between atmospheric pressure and the vacuum is calculated to be smaller than the actual brake booster pressure (e.g., the actual brake booster pressure). Consequently, the A / C is deactivated despite the fact that sufficient vacuum is stored in the brake booster. Particularly during the cold start phase, before the engine warms up, after the vehicle has been started, the resistance of the combustion engine and all auxiliary components increases significantly, so the required torque is greatly increased, and the vacuum could become insufficient, resulting in repeated A / C on / off cycling.

[0008] This means that the side effect is a frequent occurrence of the A / C switching off in a cold start condition before the vehicle has warmed up, which worsens the cooling performance, and it is not possible to dehumidify the vehicle, which in turn results in a customer complaint due to the generation of moisture on the windshield.

[0009] The foregoing information disclosed in this “background of the invention” section is provided solely to enhance understanding of the general background of the invention and cannot be considered an acknowledgment or any kind of suggestion that this information is part of the prior art as already known to the person skilled in the art.

[0010] Furthermore, methods and systems for controlling a compressor of a cold-start vehicle are known from DE 10 2016 122 979 A1 and DE 103 16 100 B4, respectively. In particular, DE 10 2016 122 979 A1 discloses a compressor control device comprising: a data acquisition device which acquires state data that includes at least one of a vehicle speed, an engine speed, an accelerator pedal position value, and an inclination measurement value; and a control device which determines whether the engine speed and the accelerator pedal position value of the state data meet an oscillation acceleration entry condition if the vehicle speed is within a predetermined range; and which sets a basic operating rate of a compressor according to the engine speed and the accelerator pedal position value if the engine speed and the accelerator pedal position value of the state data meet the oscillation acceleration entry condition.and which generates the final operating rate of the compressor using the basic operating rate, a slope constant according to the slope measurement value, and an air temperature compensation constant according to an air temperature, and which controls the operation of the compressor based on the final operating rate. EXPLANATION OF THE INVENTION

[0011] It is an object of the present invention to provide a system and a method for controlling a compressor of a cold-start vehicle, in which the A / C operation of the compressor is changed to a minimum operation in a situation in which the combustion engine vacuum is insufficient at the time of a cold start of the vehicle and the required torque is reduced accordingly, thereby preventing the air conditioning from being repeatedly switched on and off.

[0012] The problem is solved by the features of the independent patent claims. Advantageous embodiments of the invention are described in the dependent claims.

[0013] According to an exemplary embodiment of the present invention, a system for controlling a compressor of a cold-start vehicle (e.g., a cold-start vehicle, in particular, for example, a cold-start motor vehicle) comprises: an internal combustion engine control unit (ECU) which controls a fuel injection quantity corresponding to an internal combustion engine load and a throttle valve opening amount by taking into account a required torque necessary for an air conditioning system (hereinafter referred to as "A / C"), an operating information acquisition device for acquiring operating information according to the vehicle's driving condition, a compressor (e.g.,air conditioning compressor), which generates pressure by means of a piston operation of a cylinder using power from the internal combustion engine during operation of the air conditioning (A / C), an air conditioning relay which is switched on (ON) in response to an operating signal from the ECU when the air conditioning is in operation / is switched on, and is switched off (OFF) when the air conditioning is stopped / is stopped, and a control device which modulates an internal combustion engine vacuum of an intake manifold, which is stored in the brake booster, with (e.g. open, closed) a value that is determined by subtracting the internal combustion engine pressure (e.g.inlet manifold pressure) is determined from the atmospheric pressure, which is obtained from the operating information, and wherein, if during operation of the air conditioning system the coolant temperature is lower than the predetermined temperature and the inlet manifold vacuum is lower than the first threshold, a cold start inlet manifold vacuum insufficient event or process (hereinafter referred to as: cold start inlet manifold vacuum insufficient event - e.g. an event or process in which an inlet manifold vacuum is insufficient during a cold start) is generated in order to reduce the A / C operation (e.g. A / C duty cycle) of the compressor according to the entry into a vacuum recovery mode (hereinafter referred to as: vacuum recovery mode).

[0014] The compressor may also have a pressure regulator for regulating the degree of actuation (e.g. actuation rate and / or actuation stroke) of the piston by changing the angle of the swashplate or angled disk according to the A / C operating control signal applied by the control unit.

[0015] Furthermore, the operating information acquisition device can acquire at least one piece of operating information from the air conditioning operating status, the vehicle speed, the atmospheric pressure, the inflation pressure (e.g. tire inflation pressure), the accelerator pedal actuation status, the brake actuation status, the sea level, the road inclination, a timer and the coolant temperature.

[0016] The control unit can also detect or determine (hereinafter referred to as: detect) the cold start intake manifold vacuum insufficient event for a first predetermined time if all of the following conditions are met: the accelerator pedal is not depressed, the coolant temperature is lower than a predetermined temperature, the vehicle speed is lower than the predetermined vehicle speed at which the vehicle is not completely stopped, and the intake manifold vacuum is below the first threshold at which the intake manifold vacuum is insufficient.

[0017] Furthermore, the control unit can enter vacuum recovery mode and change (e.g., switch) the compressor to minimum (min) A / C operation if the air conditioning relay operating signal is switched off immediately after the air conditioning relay operating signal is switched on, for a predetermined number of times within the first specified time, which is defined as the cold start intake manifold vacuum insufficient event.

[0018] Furthermore, the control unit can cancel or release or resolve (hereinafter also referred to simply as: cancel) the cold start intake manifold vacuum insufficient event if the coolant temperature rises to a predetermined coolant temperature or higher within the first specified time period determined by the cold start intake manifold vacuum insufficient event.

[0019] Furthermore, the control unit can cancel the compressor's A / C operation reduction control if a second predetermined time has elapsed since entering the vacuum recovery mode.

[0020] Furthermore, the control unit can restrict (e.g. prevent, block) entry into the vacuum recovery mode if the vehicle is in an uphill driving condition with a predetermined gradient or more, or is located on a highland or elevated area (hereinafter referred to as: highland) above a predetermined altitude or height (hereinafter referred to as: altitude).

[0021] Furthermore, the control unit can perform the required torque control to determine the required torque reduction amount of the compressor simultaneously with the A / C operation reduction control (e.g. control to reduce A / C operation) of the compressor and send this (the determined required torque reduction amount) to the ECU.

[0022] Furthermore, the ECU can reduce the amount of fuel injected upon receiving the required torque from the control unit according to the entry into vacuum recovery mode, in order to control the throttle valve to close.

[0023] Furthermore, a method for controlling a compressor of a cold-start vehicle according to an exemplary embodiment of the present invention comprises: a) controlling the compressor with a defined (e.g., set) basic A / C operation when the vehicle is started (ON) and the vehicle's air conditioning (hereinafter referred to as "A / C") is in operation, b) determining the vacuum of the intake manifold, which is stored in the brake booster, with (e.g.,a) a value obtained by collecting operating information and subtracting the inlet manifold pressure from atmospheric pressure, c) generating a cold start inlet manifold vacuum insufficient event during the first predetermined time if the coolant temperature is lower than a predetermined temperature and the vacuum is lower than a first threshold, and d) reducing the A / C compressor operation according to entering the vacuum recovery mode if the condition that the air conditioning relay operating signal is turned on and then off within the first predetermined time is repeated a predetermined number of times.

[0024] Furthermore, in step c) the cold start intake manifold vacuum insufficient event can be generated if the accelerator pedal is not actuated based on the operating information (APS = OFF) and the vehicle also meets the operating condition of a low speed, which is lower than a predetermined vehicle speed at which the vehicle is not completely stopped.

[0025] Furthermore, step c) may include: generating a corresponding event hold signal for the first specified time at the same time as the cold start intake manifold vacuum insufficient event, and monitoring an operating signal of the air conditioning relay.

[0026] Furthermore, step c) may include: Canceling or resolving (hereinafter referred to as: canceling) the cold start intake manifold vacuum insufficient event if the coolant temperature rises to a predetermined coolant temperature or higher within the first specified time period determined by the cold start intake manifold vacuum insufficient event.

[0027] Furthermore, step d) may include: generating a hold signal of the vacuum recovery mode for a second specified time to prevent the compressor from operating in basic A / C operation.

[0028] Furthermore, step d) may include: performing a vacuum recovery control with a minimum (min) A / C operation, in which the basic A / C operation is reduced according to the entry into vacuum recovery mode.

[0029] Furthermore, step d) may include: performing the required torque control to determine the required torque reduction amount of the compressor simultaneously with the A / C operation reduction control of the compressor and sending the same (the required torque reduction amount) to the ECU.

[0030] Furthermore, step d) may include: canceling the vacuum recovery mode and returning to basic A / C operation control (e.g., control with basic A / C operation) when the second specified time set in the vacuum recovery mode has elapsed.

[0031] Furthermore, step c) may include: restricting (e.g. preventing, blocking) entry into the vacuum recovery mode when the vehicle is in an uphill driving condition with a predetermined gradient or more, or on a highland above a predetermined altitude.

[0032] According to an exemplary embodiment of the present invention, it is possible to reduce the frequency of A / C shutdown due to insufficient vacuum in the intake manifold and to ensure the dehumidification performance accordingly by detecting the condition that the vacuum in the intake manifold is insufficient, wherein the vacuum in the intake manifold is ensured by the pre-A / C operation reduction control and the reduction of the required torque.

[0033] Furthermore, there is an effect in that the operation of the compressor is repeatedly restricted by limiting the use of the maximum (Max-)A / C operation of the compressor in a situation in which the intake manifold pressure of the vehicle is insufficient at the time of a cold start of the vehicle.

[0034] Furthermore, by omitting the brake booster sensor and utilizing the difference between atmospheric pressure and the pressure of the intake manifold, it is possible to reduce the cost increase and improve customer satisfaction by improving the conflicting goal relationship between dehumidification / cooling performance and braking performance.

[0035] The methods and devices of the present invention have further features and advantages, which will become clear from the accompanying drawings included herein and the following detailed description, which together serve to explain certain principles of the present invention, or which are detailed therein. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a concept diagram showing an A / C shutdown logic using a conventional vacuum from an intake manifold. Fig. Figure 2 schematically shows a system for controlling a compressor according to an exemplary embodiment of the present invention. Fig. Figure 3 is a concept diagram illustrating a control logic with a variable compressor according to an exemplary embodiment of the present invention. Fig. Figure 4 shows an example of the negative pressure recovery mode entry condition and the A / C operation control according to an exemplary embodiment of the present invention. Fig. 5 and Fig. Figure 6 are flowcharts which schematically represent a method for controlling a compressor according to an exemplary embodiment of the present invention.

[0036] It is understood that the attached drawings are not necessarily to scale and represent a somewhat simplified depiction of various properties in order to illustrate the basic principles of the invention. The specific design features of the present invention, including, for example, specific dimensions, orientations, positions, and shapes as disclosed herein, are (at least) partially determined by the respective intended application and usage environment.

[0037] In the figures, reference numerals throughout numerous figures of the drawings refer to identical or equivalent components of the present invention. DETAILED DESCRIPTION

[0038] Reference will now be made in detail to various embodiments of the present invention, examples of which are illustrated in the accompanying drawings and described below. Although the invention is described in connection with the exemplary embodiments, it is clear that the present description is not intended to limit the invention to these exemplary embodiments. On the contrary, the invention is intended to cover not only the exemplary embodiments but also various alternatives, modifications, variations, and other embodiments that may be included within the scope of the invention as defined by the attached claims.

[0039] In the following detailed description, only certain exemplary embodiments of the present invention are shown and described for illustrative purposes. As will be clear to those skilled in the art, the described embodiments can be modified in numerous different ways without deviating from the essence or scope of the present invention. Consequently, the drawings and descriptions are to be regarded as illustrative and not limiting in nature. Identical reference numerals denote similar elements throughout the description.

[0040] Furthermore, unless explicitly stated otherwise, the word "show" and variations thereof, such as "shows" or "showing," are to be understood as signifying the inclusion of specified elements, but not the exclusion of any other element. Additionally, the terms "...-er," "...-or," and "-module," as described in this document, refer to units for processing at least one function and one operation, and these may be implemented using hardware components or software components and combinations thereof.

[0041] To effectively describe the technical characteristics of the present invention, the following exemplary embodiment of the present invention may modify, integrate or separate terms accordingly so that they are clearly understood by a person skilled in the art, and the present invention is not limited thereto.

[0042] Throughout this description, the vacuum of the intake manifold (e.g., intake manifold or intake port) refers to a determined value that estimates the negative brake vacuum stored in the brake booster by means of a value obtained by subtracting the intake manifold pressure from atmospheric pressure. Therefore, in the exemplary embodiment of the present invention, "vacuum" means "vacuum of the intake manifold," not booster vacuum, unless otherwise specified.

[0043] It should be noted that the system and method for controlling the compressor of the present invention, which are described below, differ from those of conventional technology, in which the sensor for measuring the brake vacuum is located, due to the characteristics of solving the problem of utilizing the vacuum of the intake manifold.

[0044] Now, a system and a method for controlling a compressor of a cold-start vehicle (e.g., a cold-starting vehicle, in particular, for example, a cold-starting motor vehicle) according to an exemplary embodiment of the present invention are described in detail with reference to the drawings.

[0045] Fig. Figure 2 schematically shows a system for controlling a compressor according to an exemplary embodiment of the present invention.

[0046] Fig. Figure 3 is a concept diagram illustrating a control logic with a variable compressor according to an exemplary embodiment of the present invention.

[0047] With reference to Fig. 2 and Fig. 3 comprises a system 10 for controlling a compressor according to an exemplary embodiment of the present invention, comprising an internal combustion engine control unit (ECU) 11, an air conditioning relay RL, an operating information acquisition device 12, a compressor 13, a condenser 14, an evaporator 15, a storage unit 16 and a control device 17.

[0048] Before fully describing the present invention, the operation of the system 10 for controlling the compressor according to the exemplary embodiment of the present invention is described with reference to the peripheral devices by means of the property of using the vacuum, which is not the brake vacuum measured by the actual sensor.

[0049] The brake booster typically stores vacuum to mechanically amplify the force with which the driver presses the brake pedal and transmits pressure to the brake to decelerate the vehicle when the brake pedal is pressed.

[0050] At this point, the source of the pressure used by the brake booster is the intake manifold vacuum, which is the difference between atmospheric pressure (e.g., ambient air pressure) and the intake manifold pressure. The intake manifold vacuum is greater (in magnitude) when the throttle valve (TPS) is closed, due to the vacuum created by the throttle valve, and is lower (in magnitude) when the throttle valve is open. Furthermore, when the driver depresses the accelerator pedal (also called the gas pedal) to open the throttle valve (TPS), the atmospheric pressure and the intake manifold pressure equalize due to the inflow of air, so that the intake manifold vacuum approaches zero.For this reason, despite the fact that sufficient vacuum is stored in the actual brake booster, it is determined that the vacuum of the intake manifold is low, which has the side effect of causing frequent A / C shutdowns.

[0051] Under cold start conditions, before the coolant temperature reaches a certain level prior to warm-up after the vehicle starts, the intake manifold vacuum is maintained, but kept very low due to conditions such as a high idle speed and catalytic converter heating. Since, in this situation, the intake manifold vacuum is already insufficient to operate the compressor at normal duty (100% duty) during air conditioning (A / C) operation, the A / C, due to the nature of the compressor's operating logic, switches off almost simultaneously with the A / C being switched on, then switches back on, and then immediately switches off again.

[0052] There is a situation in which the A / C cannot be used for a few minutes due to such a situation. If, in such a situation, there is a humid environment, such as a rain shower, the vehicle cannot be dehumidified.

[0053] The control system 10 for controlling the compressor according to the exemplary embodiment of the present invention accordingly changes the A / C operation (“A / C duty”) in a state in which the vacuum of the intake manifold is insufficient at the time of the cold start of the vehicle to the minimum operation, which reduces the torque required to prevent the air conditioning (A / C) from being switched off due to the reduction in the combustion engine load and to keep the operating state of the compressor at a minimum (Min), which improves the aforementioned side effects.

[0054] The ECU 11 is a computing device that controls the entire operating process for running the internal combustion engine and controls the fuel injection quantity according to the operation of auxiliary units of the internal combustion engine (compressor, alternator, etc.), so that the internal combustion engine can be operated at a stable speed.

[0055] The throttle position sensor (TPS) is controlled according to the fuel injection quantity control of ECU 11. As the fuel injection quantity increases, the throttle position sensor (TPS) becomes larger, and as the fuel injection quantity decreases, the throttle position sensor (TPS) becomes smaller.

[0056] When the throttle position sensor (TPS) opening is increased, the intake manifold vacuum, which is the difference between atmospheric pressure and intake manifold pressure, decreases. At this point, ECU 11 receives a signal indicating that the intake manifold vacuum is insufficient and moves the throttle valve towards the closing position.

[0057] Conventionally, there are numerous methods for moving the throttle valve (TPS) in its closing direction. Generally, however, a method of stopping the auxiliary unit's operation can be used. Typically, the A / C shutdown control is used to stop the compressor 13 for a few seconds, with a minor side effect due to the relatively instantaneous shutdown. The A / C shutdown can reduce the internal combustion engine load, with the throttle valve (TPS) moving in the closing direction to promote the increase in vacuum.

[0058] Relay RL is designed to direct the power of the combustion engine to compressor 13 according to the required torque when the air conditioning (A / C) is operating. Relay RL is switched on (ON) when the air conditioning is on and switched off (OFF) when the air conditioning is off (A / C OFF).

[0059] This means that during A / C shutdown control, the ECU 11 switches the air conditioning relay RL to OFF in order to reduce the required torque used in the compressor 13, while controlling the throttle valve (TPS) in the closing direction and restoring the vacuum (e.g., the vacuum recovers to a suitable level).

[0060] The ECU 11, on the other hand, controls the fuel injection quantity by taking into account not only the torque required by the driver according to the accelerator pedal operation (APS), but also the torque required by auxiliary units (e.g. a compressor, an alternator or the like) of the internal combustion engine.

[0061] The ECU 11 takes into account the required torque for the operation of the air conditioning (A / C), which is set as the standard according to the driver's air conditioning (A / C) temperature setting (cooling condition), in the total required torque, adjusting the throttle valve (TPS) opening amount.

[0062] In the following description according to the exemplary embodiment of the present invention, the ECU 11 controls the reduction of the A / C operation (e.g., A / C duty cycle, A / C duty rate – in other words: a characteristic value in percent (e.g., duty cycle) which indicates the degree of current operation (e.g., the current power) of the compressor) of the compressor 13 according to the vacuum recovery in the state in which the vacuum is insufficient at the same time as the cold start state of the control unit 17, and thereby receives the reduced torque demand. At this point, the ECU 11 immediately reduces the fuel injection quantity according to the received reduced torque demand and supports an interlocking control of the vacuum recovery mode or vacuum recovery mode or...Vacuum recovery mode (hereinafter referred to as vacuum recovery mode) for controlling the throttle valve (TPS) in its closing direction in order to maintain the minimum (min) operating state without stopping the compressor 13.

[0063] The air conditioning (A / C) system is part of the vehicle's climate control system. The A / C system, controlled by ECU 11, a key component of the variable torque control system, variably regulates the compressor's partial load to prevent the brake vacuum from dropping to the A / C shutdown level.

[0064] For this purpose, the air conditioning (A / C) system features compressor control logic under the vehicle's cold start condition to enable variable control of the compressor to operate efficiently according to the vehicle's driving information and environmental conditions.

[0065] The air conditioning (A / C) system comprises an operating information acquisition unit 12, a compressor 13, a condenser 14, a storage unit 16, and a control unit 17. The air conditioning (A / C) system is used for cooling, ventilation, and heating in the vehicle.

[0066] The air conditioning (A / C) improves the cooling performance as the operating ratio of the compressor 13 increases, and the operating ratio of the compressor 13 is determined according to the variable A / C operation control of the control unit 17 depending on the determination of the lack of vacuum of the intake manifold based on the operating information.

[0067] The operating information acquisition device 12 acquires operating information measured by numerous sensors and control units according to the vehicle's driving condition. This operating information can be data measured by the sensor and control unit, or information processed into a form necessary for controlling the compressor 13.

[0068] For example, the operating information acquisition device 12 can provide values, which are acquired by a vehicle speed sensor, an atmospheric pressure sensor, an intake manifold pressure sensor, a speed change stage (e.g. transmission), an accelerator pedal sensor (APS), a brake pedal sensor (BPS), a height sensor (e.g. altimeter), a tilt sensor, a timer, a coolant sensor (e.g. especially coolant temperature sensor), etc., to the control unit 17.

[0069] The compressor 13 compresses the refrigerant drawn in from the evaporator 15 during operation of the air conditioning (A / C) system and delivers the compressed refrigerant to the condenser 14. The compressor 13 can be a variable-capacity compressor (e.g., a variable displacement compressor) for a vehicle, which generates pressure through the piston operation of a cylinder using the power of the internal combustion engine, transmitted by a belt. For example, the compressor 13 can have a pressure regulator configured to change the angle of the swashplate or swash plate (gear) according to the applied A / C operation control signal and to adjust the degree of actuation (e.g., actuation rate and / or actuation stroke) of the piston (i.e., piston movement or piston dynamics).

[0070] The condenser 14 condenses and liquefies the refrigerant compressed by the compressor 13.

[0071] The evaporator 15 evaporates the refrigerant that has been liquefied by the condenser.

[0072] Furthermore, the description of the basic structure of the air conditioning (A / C) system is well known to experts, so an unnecessary description is omitted.

[0073] Memory 16 stores a program and data for controlling compressor 13 and stores data generated according to the operating sequence.

[0074] Memory 16 stores a fully automatic temperature control (FATC, derived from the English "Full Automatic Temperature Control") based on a target duty control map (MAP1) for the control of compressor 13.

[0075] Furthermore, the memory 16 can define and store an A / C duty control map MAP2 for variable control of the compressor 13 and a required torque control map MAP3, which corresponds to the A / C duty control map MAP2 in the situation of insufficient vacuum of the intake manifold.

[0076] The control unit 17 is an air conditioning control unit for controlling the entire operation of the air conditioning system (A / C) and, in cooperation with the ECU 11, enters the vacuum recovery mode depending on the insufficient intake manifold vacuum event during cold start in order to control the compressor 13 in a variable manner.

[0077] The control unit 17 detects the use of the air conditioning (A / C ON / OFF), the vehicle speed, the atmospheric pressure, the intake manifold pressure, the accelerator pedal actuation state (APS ON / OFF), the brake actuation (BPS ON / OFF), the altitude, the road inclination, the timer, the coolant temperature and the like through the operating information acquisition unit 12.

[0078] The control unit 17 controls the compressor 13 to a maximum duty of 100% for an initial number of seconds according to a basic A / C operation control logic based on the normal FATC when the air conditioning system is in operation (A / C ON).

[0079] The control unit 17 determines the vacuum of the intake manifold, which is stored in the brake booster, with (e.g. open, closed) a value obtained by subtracting the pressure of the intake manifold from the atmospheric pressure recorded on the basis of the operating information.

[0080] The control unit 17 determines the cold start intake manifold vacuum insufficient event based on the collected operating information when the air conditioning is in operation (A / C ON).

[0081] The control unit 17 can determine that a cold-start intake manifold vacuum insufficient event has occurred if the following conditions are all met: the coolant temperature is lower than a predetermined temperature (e.g., 50°C), the vehicle speed is lower than the predetermined vehicle speed (e.g., 0.1 km / h ≤ 15 km / h) at which the vehicle is not completely stopped, and the pressure (e.g., the intake manifold vacuum) is below the first threshold value T1 at which the intake manifold vacuum is insufficient. At the same time as the event detection, the control unit 17 can generate a corresponding event hold signal (Low_bp = 1) for an initial predetermined time (e.g., 100 seconds) and monitor an operating signal from the air conditioning relay RL.

[0082] The control unit enters vacuum recovery mode and controls compressor 13 to minimum A / C duty if the air conditioning relay (RL) signal repeatedly switches on and off a predetermined number of times (for example, twice) within the initial set time. In this case, if the maximum A / C duty is 100%, minimum A / C duty control means reducing the A / C duty to a minimum permissible value (duty limit) of 50%, at which the air conditioning (A / C) does not switch off.

[0083] At this time, the control unit 17 generates the vacuum recovery mode maintenance signal (Low_bp_off = 1) for the second specified time (e.g. 300 seconds) at the same time when the vacuum recovery mode is entered, and the control unit 17 restricts the operation of the compressor 13 by restricting the maximum (Max) A / C operation (e.g. the control unit restricts operation to maximum (Max) compressor A / C operation).

[0084] However, the control unit 17 can suddenly clear, release, or resolve the cold-start intake manifold vacuum insufficient event (hereinafter referred to simply as "clear") if the coolant temperature rises above a predetermined water temperature (e.g., 50°C) within the initial time period defined as the cold-start intake manifold vacuum insufficient event. It is determined that the coolant temperature has reached a specific temperature after warm-up, and the cold-start intake manifold vacuum insufficient event is cleared. Subsequently, A / C operation can be controlled by entering vacuum recovery mode, subject to fluctuations in the intake manifold vacuum.

[0085] For example, Fig. 4 represents a negative pressure recovery mode entry condition and an A / C operation control according to an exemplary embodiment of the present invention.

[0086] Referring to Fig. Figure 4 shows the control device 17 according to an exemplary embodiment of the present invention graphically showing the result of carrying out the A / C operation control by entering the vacuum recovery mode according to the change in the vacuum of the intake manifold over time.

[0087] The control unit 17 controls the compressor 13 to a general FATC target operation-based basic A / C operation.

[0088] If the intake manifold vacuum drops below the first threshold T1, the control unit 17 enters vacuum recovery mode if the vacuum can be restored by the A / C operation control, and the A / C operation is reduced without A / C shutdown, whereby the vacuum can be restored (increased).

[0089] The first threshold value T1 (for example, 260 hPa) represents a value that is set as an A / C operation control start condition to prevent A / C shutdown, with a vacuum recovery control reference line that indicates a state in which the intake manifold vacuum is insufficient.

[0090] Furthermore, the second threshold T2 (for example, 240 hPa) is the A / C cut-off control vacuum reference line, and the A / C cut-off control is initiated when the intake manifold vacuum drops below the second threshold.

[0091] This means that the first threshold T1 (for example, 260 hPa) can be set to a higher value than the second threshold in order to initiate the A / C operation control to predict a vacuum condition in which the vacuum of the intake manifold decreases below a second threshold T2 (for example, 240 hPa), which is an A / C shutdown control condition, and to prevent it.

[0092] The control unit 17 controls the basic A / C operation to a maximum value of 100% (Max) when the vacuum of the intake manifold exceeds the first threshold value T1 and the vacuum is sufficient.

[0093] When the intake manifold vacuum drops below the first threshold T1, the control unit 17 initiates the vacuum restoration control, similar to the first duty control, to change the A / C operation to the minimum value (Min), which is below 50%. At this point, the control unit 17 applies the A / C operation control signal, which changes the maximum A / C operation (Max) to the minimum A / C operation (Min), to the compressor 13, and then the A / C operation (e.g., the minimum A / C operation and / or the maximum A / C operation) is maintained for a predetermined hold time (e.g., 3 seconds) and then the restriction is lifted.

[0094] In particular, during a cold start condition of the cold start intake manifold vacuum insufficient event, before the coolant temperature reaches a certain temperature before warm-up after vehicle start, the control unit 17 enters the vacuum recovery mode and the control unit 17 can change the A / C operation to the minimum (Min-)A / C operation, since the internal combustion engine vacuum is kept at a very low state, which falls below the second threshold value T2.

[0095] If, at this time, the condition in which the air conditioning relay (RL) switches off at the same time as the A / C ON to A / C OFF and switches off immediately after the A / C ON to A / C OFF (e.g. the condition in which, when the air conditioning is switched on, the air conditioning relay is first switched on and immediately switched off again, and then switched on again and immediately switched off again) is repeated, the control unit 17 can detect the entry into the vacuum recovery mode.

[0096] After the control unit 17 has performed the primary or initial operating control and then returned to the basic A / C operating control, the control unit 17 can prohibit (restrict) re-entry into the negative pressure recovery mode within a predetermined re-entry prohibition time (e.g., 0.2 seconds). This serves to prevent the phenomenon of the minimum A / C operation (Min) being continuously maintained beyond the holding time.

[0097] The control unit 17 can also generate the required torque control amount, which is reduced according to the fluctuation of the minimum A / C operation, and transmit it to the ECU 11 of the internal combustion engine.

[0098] The Required Torque Control Amount refers to the amount of torque required by the air conditioning (A / C) system, which can be reduced by reducing the A / C operation maximum output value (Max) to the minimum output (Min) for each of the tilt angle conditions.

[0099] For example, if the required torque is 10 Nm when the tilt plate angle (e.g., tilt angle of the swashplate) for the maximum (Max) A / C operation output is 100%, then the control unit 17 subtracts the first required torque control amount of 5 Nm according to the A / C operation reduction control, in which the tilt plate angle is reduced to 50%, and the control unit 17 can transmit the required torque, reduced to 5 Nm, to the ECU 11.

[0100] However, as in Fig. As shown in Figure 3, the control unit 17 can exceptionally restrict (e.g., prevent, block) entry into the vacuum recovery mode if, taking into account the uphill driving conditions, the vehicle is under an uphill driving condition requiring high output power (e.g., in an uphill driving state) of a predetermined gradient (e.g., predetermined slope).

[0101] Furthermore, the control unit 17 can exceptionally restrict (e.g., prevent, block) entry into the vacuum recovery mode if the vehicle is located in a highland or higher-altitude area (e.g., 1500 m) or higher, taking into account the highland condition. This occurs because the number of assistance applications (power) in the highlands is reduced to almost half at altitudes of approximately 1500 m or higher, assuming that the vacuum reservoir of the brake booster supports five actuations of the normal reference brake compared to flat terrain.

[0102] A method for controlling a compressor of a cold-start vehicle according to an exemplary embodiment of the present invention is described with reference to Fig. 5 and Fig. 6 is described based on the configuration of the compressor control system 10 described above. However, the detailed configuration of the compressor control system 10 can be divided into individual functions or integrated into a single system. Therefore, when describing the method for controlling the compressor of the cold-start vehicle with reference to the figures, the subject is referred to as the compressor control system 10.

[0103] Fig. 5 and Fig. Figure 6 are flowcharts which schematically represent a method for controlling a compressor according to an exemplary embodiment of the present invention.

[0104] With reference to Fig. 5 and Fig.6 In the system for controlling the compressor according to an exemplary embodiment of the present invention, the compressor 13 is controlled with a defined basic maximum (Max-)A / C duty based on the FATC S2 when the vehicle is started (ON) S1 and the vehicle's air conditioning (A / C) is in operation.

[0105] The system for controlling the compressor 10 collects operating information according to the driving of the vehicle through the operating information acquisition device 12 and monitors the entry condition into the vacuum recovery mode based on the cold start intake manifold vacuum insufficient event, as shown in steps S3 to S6 below.

[0106] The compressor control system 10 detects or determines the insufficient cold start intake manifold vacuum event for a first predetermined time S7 if all of the following conditions are met: the accelerator pedal is not depressed (APS = OFF) (S3; YES), the coolant temperature is lower than a predetermined temperature (e.g., 50°C) (S4; YES), the vehicle speed is lower than the predetermined vehicle speed (0.1 km / h ≤ vehicle speed ≤ 15 km / h) at which the vehicle is not completely stopped (S5; YES), and the intake manifold vacuum is below the first threshold T1 at which the intake manifold vacuum is insufficient (S6; YES). If, however, any of the conditions S3 to S6 are not met (NO), then the insufficient cold start intake manifold vacuum event is not detected.

[0107] The system for controlling the compressor 10 generates the corresponding event hold signal (Low_bp = 1) for a first fixed time (for example 100 seconds) at the same time as the event detection and monitors the operating signal of the air conditioning relay RL.

[0108] The compressor control system 10 counts a situation in which the air conditioning relay signal (RL) is switched on and then off within an initial defined time (S8), and enters the vacuum recovery mode S10 if the counter value is repeated multiple times (e.g., twice) (S9; YES). However, if the counter value is not repeated multiple times (e.g., twice) within the initial defined time (S9; NO), the compressor control system 10 cancels the event and proceeds to step S2.

[0109] At this time, the control unit 17 generates the vacuum recovery mode maintenance signal (Low_bp_off = 1) for the second specified time (e.g. 300 seconds) at the same time when the vacuum recovery mode is entered, and the control unit 17 restricts the operation of the compressor 13 by restricting the maximum (Max) A / C operation (e.g. the control unit restricts operation to maximum (Max) compressor A / C operation) S11.

[0110] The compressor control system 10 performs the vacuum recovery control to reduce the internal combustion engine load by reducing the maximum A / C operation to the minimum A / C operation according to entering the vacuum recovery mode (S12).

[0111] However, if only the A / C operation is reduced by the vacuum restoration control, then the actual combustion engine load is reduced, but the ECU 11 does not know to what extent the torque used in the compressor 13 is reduced, so the vacuum restoration effect may be minor or insignificant.

[0112] Therefore, the compressor control system 10 determines the required torque reduction amount of the compressor 13 according to the A / C operation reduction simultaneously with the A / C operation reduction control at the time of entering the vacuum recovery mode and sends this to the ECU 11. The required torque control is performed S13. At this time, the compressor control system 10 can send the required torque, which is reduced by subtracting the required torque control amount reduced by the minimum (Min-) A / C operation, from the required torque output value according to the maximum (Max-) A / C operation, to the ECU 11.

[0113] The system for controlling compressor 10 counts the second fixed time and, if this has not elapsed (S14; No), maintains the operating restriction of the maximum (Max-)A / C operation (e.g. to the maximum (Max-)A / C operation).

[0114] The compressor control system then deactivates the vacuum recovery mode (S15) when the second specified time has elapsed (S14; JA). For example, the restriction is lifted to allow operation at up to 100% maximum A / C in a situation where the vacuum recovery mode is limited to minimum (Min) A / C operation of less than 50%.

[0115] According to an exemplary embodiment of the present invention, this makes it possible to reduce the frequency of A / C shutdown due to insufficient vacuum in the intake manifold and accordingly ensure dehumidification performance by detecting the condition that the vacuum in the intake manifold is insufficient, wherein the vacuum in the intake manifold is ensured by the pre-A / C operation reduction control and the reduction of the required torque.

[0116] Furthermore, there is an effect in that the operation of the compressor is repeatedly restricted by limiting the use of the compressor's maximum (Max-)A / C operation in a situation where the vehicle's intake manifold pressure is insufficient at the time of a cold start.

[0117] Furthermore, by omitting the brake booster sensor and utilizing the difference between atmospheric pressure and the pressure of the intake manifold, it is possible to reduce the cost increase and improve customer satisfaction by improving the conflicting goal relationship between dehumidification / cooling performance and braking performance.

[0118] The exemplary embodiment of the present invention described above can be implemented not only by a device and a method described above, but also by a program that implements functions corresponding to the configurations of the exemplary embodiment, or by a storage medium that stores the program. Such an implementation can be carried out easily by a person skilled in the art.

[0119] To facilitate explanation and precise definition in the attached claims, the terms “above…”, “below…”, “inner…”, “outer…”, “high”, “down”, “upwards”, “downwards”, “front…”, “behind…”, “front”, “rear”, “inwards”, “outwards”, “within”, “outside”, “inside”, “outside”, “inside”, “outside”, “forwards” and “backwards” are used to describe features of the exemplary embodiments with reference to their positions as shown in the drawings.

[0120] The preceding descriptions of certain exemplary embodiments of the present invention served the purpose of illustration and description. They are not intended to be exhaustive or to limit the invention to precisely the disclosed forms, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were selected and described to illustrate certain principles of the invention and its practical applicability, thereby enabling the person skilled in the art to produce and apply various exemplary embodiments of the present invention, as well as various alternatives and variations thereof. It is intended that the scope of the invention is defined by the accompanying claims.

Claims

[1] System (10) for controlling a compressor (13) of a cold-start vehicle, comprising the system: an internal combustion engine control unit (ECU, 11) which controls a fuel injection quantity corresponding to an internal combustion engine load and an opening amount of a throttle valve depending on a required torque which is necessary for an air conditioning (A / C), an operational information acquisition device (12) for acquiring operational information according to the driving condition of the cold start vehicle, a compressor (13) which generates pressure by means of a piston operation in a cylinder using the power of an internal combustion engine during the operation of the air conditioning system, an air conditioning relay (RL) which is switched on in response to an operating signal from the ECU when the air conditioning is in operation, and is switched off when the air conditioning is stopped, and a control device (17) which is connected to the ECU (11) and determines an internal combustion engine intake manifold vacuum stored in a brake booster with a value obtained by subtracting the internal combustion engine vacuum from the atmospheric pressure, which is detected by the operating information acquisition device (12), and wherein, if during operation of the air conditioning system a coolant temperature is lower than a predetermined temperature and an intake manifold vacuum is lower than a first threshold value (T1), a cold start intake manifold vacuum insufficient event is generated to reduce A / C operation of the compressor (13) according to an entry into a vacuum recovery mode. [2] System (10) for controlling the compressor (13) of the cold start vehicle according to claim 1, wherein the compressor (13) further comprises a pressure regulator for regulating a degree of actuation of the piston by changing the angle of a swashplate according to an A / C operation control signal which is applied by the control device (17). [3] System (10) for controlling the compressor (13) of the cold start vehicle according to claim 1 or 2, wherein the operating information acquisition device (12) acquires at least one operating information from an air conditioning operating state, a vehicle speed, atmospheric pressure, a filling pressure, an accelerator pedal actuation state, a brake actuation state, a sea level, a road inclination, a timer and a coolant temperature. [4] System (10) for controlling the compressor (13) of the cold-start vehicle according to any one of claims 1 to 3, wherein the control device (17) detects the cold-start inlet manifold vacuum insufficient event for a first predetermined time when an accelerator pedal is not actuated, a coolant temperature is lower than a predetermined temperature, a vehicle speed is lower than a predetermined vehicle speed at which the cold-start vehicle is not completely stopped, and the inlet manifold vacuum is below the first threshold (T1) at which the inlet manifold vacuum is insufficient. [5] System (10) for controlling the compressor (13) of the cold start vehicle according to claim 4, wherein the control device (17) enters the vacuum recovery mode and changes the compressor (13) to a minimum A / C operation if it repeatedly switches off an air conditioning relay operating signal a predetermined number of times within a first defined time, which is defined as the cold start intake manifold vacuum insufficient event, after the air conditioning relay operating signal has been switched on. [6] System (10) for controlling the compressor (13) of the cold start vehicle according to claim 4 or 5, wherein the control device (17) cancels the cold start intake manifold vacuum insufficient event if the coolant temperature rises to a predetermined coolant temperature or higher within a first defined time which is defined by the cold start intake manifold vacuum insufficient event. [7] System (10) for controlling the compressor (13) of the cold start vehicle according to any one of claims 4 to 6, wherein the control device (17) cancels an A / C operation reduction control of the compressor (13) when a second specified time has elapsed after entering the vacuum recovery mode. [8] System (10) for controlling the compressor (13) of the cold-start vehicle according to any one of claims 1 to 7, wherein the control device (17) limits entry into the vacuum recovery mode when the cold-start vehicle is in an uphill driving condition with a predetermined gradient or more, or is at a position above a predetermined altitude. [9] System (10) for controlling the compressor (13) of the cold start vehicle according to any one of claims 1 to 8, wherein the control device (17) performs the control of the required torque to determine a required torque reduction amount of the compressor (13) with an A / C operation reduction control of the compressor (13) and to send the determined required torque reduction amount to the ECU (11). [10] System (10) for controlling the compressor (13) of the cold start vehicle according to claim 9, wherein the ECU (11) reduces a fuel injection quantity to control the throttle valve so that it closes, upon receiving the required torque from the control device (17) according to entering the vacuum recovery mode. [11] Method for controlling a compressor (13) of a cold-start vehicle, comprising the method: a) Control, by means of a control device (17), of the compressor (13) with a defined basic air conditioning (A / C) operation (S2) when the cold start vehicle is started (S1) and an air conditioning system of the cold start vehicle is in operation, b) Determining, by means of the control device (17), a vacuum of an intake manifold which is stored in a brake booster, with a value obtained by collecting operating information and by subtracting an intake manifold pressure from an atmospheric pressure, c) Generating, by means of the control device (17), a cold start intake manifold vacuum insufficient event during a first predetermined time (S7) when a coolant temperature is lower than a predetermined temperature (S4) and the vacuum is lower than a first threshold value (T1) (S6), and d) Reducing (S11, S12), by means of the control device (17), the A / C operation of the compressor (13) according to the entry into a vacuum recovery mode (S10), if it is repeated a predetermined number of times, within the first specified time, the air conditioning relay operating signal is switched on and then off (S9). [12] Method for controlling the compressor (13) of the cold-start vehicle according to claim 11, wherein in step c): Generating the cold start intake manifold vacuum insufficient event when an accelerator pedal is not actuated based on operating information and the cold start vehicle furthermore meets a low speed operating condition which is lower than a predetermined vehicle speed at which the vehicle is not completely stopped. [13] Method for controlling the compressor (13) of the cold-start vehicle according to claim 11 or 12, wherein step c) comprises: Generating a corresponding event hold signal for the first specified time at the same time as the cold start intake manifold vacuum insufficient event, and monitoring an operating signal of an air conditioning relay (RL). [14] Method for controlling the compressor (13) of the cold-start vehicle according to any one of claims 11 to 13, wherein step c) comprises: Canceling the cold start intake manifold vacuum insufficient event if the coolant temperature rises to a predetermined coolant temperature or higher within the first specified time determined by the cold start intake manifold vacuum insufficient event. [15] Method for controlling the compressor (13) of the cold-start vehicle according to any one of claims 11 to 14, wherein step d) comprises: Generating (S11) a hold signal of the vacuum recovery mode for a second fixed time to prevent the compressor from operating in basic A / C operation. [16] Method for controlling the compressor (13) of the cold-start vehicle according to claim 15, wherein step d) comprises: Performing a vacuum recovery control with a minimum A / C operation (S12) in which the basic A / C operation is reduced according to the entry into vacuum recovery mode. [17] Method for controlling the compressor (13) of the cold-start vehicle according to any one of claims 11 to 16, wherein step d) comprises: Performing a required torque control (S13) to determine a required torque reduction amount of the compressor (13) with an A / C operation reduction control of the compressor (13) and to send the determined required torque reduction amount to an internal combustion engine control unit (ECU, 11) connected to the control device (17). [18] Method for controlling the compressor (13) of the cold-start vehicle according to any one of claims 15 to 17, wherein step d) comprises: The vacuum recovery mode will be deactivated and the system will return to basic A / C operation control when the second specified time set in the vacuum recovery mode has elapsed. [19] Method for controlling the compressor (13) of the cold-start vehicle according to claim 18, wherein step c) comprises: Restricting entry into the vacuum recovery mode when the cold-start vehicle is in an uphill driving condition with a predetermined gradient or more, or on a highland above a predetermined altitude.

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