Vehicle control device and program

Abstract

The control of the grill shutter aims to achieve both improved aerodynamic characteristics and ensured cooling performance. [Solution] A vehicle control device is disclosed which includes a grill shutter control unit that switches the open / closed state of a grill shutter provided in an opening at the front of the vehicle, and a prediction unit that predicts the future state of the vehicle based on information relating to the future driving route of the vehicle, wherein the grill shutter control unit switches the grill shutter from a closed state to an open state in a first situation where the vehicle speed is less than a first vehicle speed, based on the prediction result from the prediction unit.

Description

Technical Field

[0001] The present disclosure relates to a vehicle control device and a program.

Background Art

[0002] For the purpose of maintaining the load balance between the front and rear of the vehicle while ensuring the cooling performance according to the heat load of the engine of the vehicle, the running state of the vehicle and the temperature of the engine or the like mounted on the vehicle are detected, and based on each detection result, a technique for controlling a grille shutter is known.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the conventional technology as described above, it is difficult to achieve both improvement in aerodynamic characteristics (and accompanying improvement in fuel consumption and the like) by running with the grille shutter closed and ensuring cooling performance by running with the grille shutter open.

[0005] Therefore, on one side, an object of the present disclosure is to achieve both improvement in aerodynamic characteristics and ensuring of cooling performance with respect to control of a grille shutter.

Means for Solving the Problems

[0006] On one side, a grille shutter control unit that switches the opening / closing state of a grille shutter provided in an opening at the front of the vehicle, and a prediction unit that predicts the future state of the vehicle based on information related to the future driving route of the vehicle are provided. The grill shutter control unit is provided as a vehicle control device that, based on the prediction result from the prediction unit, switches the grill shutter from a closed state to an open state in a first situation where the vehicle speed is less than a first vehicle speed. [Effects of the Invention]

[0007] In one respect, this disclosure makes it possible to achieve both improved aerodynamic characteristics and ensured cooling performance with respect to the control of the grill shutter. [Brief explanation of the drawing]

[0008] [Figure 1] This figure shows an example of an in-vehicle system to which the control device of this embodiment can be applied. [Figure 2] This figure shows an example of the hardware configuration of the control device in this embodiment. [Figure 3] This is a functional block diagram that schematically shows an example of the functions of a control device. [Figure 4] This figure shows a time-series waveform illustrating the effect of this embodiment. [Figure 5] This is a schematic flowchart showing an example of the process performed by the control device of the embodiment. [Modes for carrying out the invention]

[0009] The following describes each embodiment in detail with reference to the attached drawings. Note that the dimensional ratios in the drawings are merely examples and are not limiting, and the shapes and other elements in the drawings may be partially exaggerated for illustrative purposes. Also, for clarity, in some cases, only a portion of parts with the same attribute are assigned reference numerals in the drawings. Furthermore, in the following description, "predetermined" means "pre-set."

[0010] Figure 1 shows an example of an in-vehicle system 1 to which the control device 100 of this embodiment can be applied.

[0011] The in-vehicle system 1 is mounted on a vehicle. In this embodiment, the vehicle on which it is mounted is an electric vehicle or a hybrid vehicle equipped with a battery 5, but it may also be a vehicle that uses only an engine as a power source.

[0012] The in-vehicle system 1 includes a refrigerant path 11 circulating through a condenser 2, evaporator 3, and chiller 4 for an air conditioning system (not shown), a refrigerant path 12 circulating through the chiller 4 and battery 5, and a refrigerant path 13 circulating through a radiator 6, power supply system 7, and electric motor 8.

[0013] The electric motor 8 is a motor for driving the vehicle, and the power supply system 7 may include an inverter and / or a converter. The battery 5 may be a high-voltage battery that powers the electric motor 8.

[0014] The radiator 6 and condenser 2 are located at the front of the vehicle (body) and cool the refrigerant by receiving airflow while driving. In this embodiment, a grill shutter 9 that can be opened and closed is located at the front of the vehicle (grille area).

[0015] When the grill shutter 9 is open, it takes in airflow and efficiently supplies it to the radiator 6 and condenser 2 (the airflow is schematically represented by arrow R1 in Figure 1). On the other hand, when the grill shutter 9 is closed, it does not take in any airflow. In this case, the aerodynamic characteristics of the vehicle body are better than when the grill shutter 9 is open (i.e., the so-called Cd value is lower).

[0016] It should be noted that the in-vehicle system 1 shown in Figure 1 is merely an example, and various modifications are possible as long as it includes a circulating path for a coolant cooled via the grill shutter 9. For example, in engine-powered vehicles and hybrid vehicles, engine-related cooling targets may be cooled by the coolant in the coolant passage 13 instead of or in addition to the power supply system 7 and electric motor 8. Also, in engine-powered vehicles, the battery 5 and the like may be omitted.

[0017] FIG. 2 is a diagram showing an example of the hardware configuration of the control device 100 of the present embodiment.

[0018] In FIG. 2, other in-vehicle electronic devices 130 are schematically illustrated in association with the hardware configuration of the control device 100.

[0019] The other in-vehicle electronic devices 130 may include various sensors such as an outside air temperature sensor 24, a vehicle speed sensor 25, a water temperature sensor 131, etc., in addition to the grill shutter 9, and other control devices such as an air-conditioning control ECU (Electronic Control Unit) 133 and a navigation ECU 134.

[0020] The water temperature sensor 131 generates an electrical signal according to the water temperature in the refrigerant path 13. The temperature / pressure sensor 132 generates an electrical signal according to the refrigerant temperature and pressure in the refrigerant path 11.

[0021] The air-conditioning control ECU 133 controls an in-vehicle air-conditioning device (not shown). The in-vehicle air-conditioning device may include the capacitor 2, the evaporator 3, the chiller 4, a compressor (not shown), etc., described above with reference to FIG. 1.

[0022] In the present embodiment, the air-conditioning control ECU 133 may request a change in the opening / closing state of the grill shutter 9 according to the state of the air-conditioning device. For example, the air-conditioning control ECU 133 may request the open state of the grill shutter 9 when the temperature / pressure in the refrigerant path 11 satisfies a predetermined condition based on the sensor information from the temperature / pressure sensor 132.

[0023] The navigation ECU 134 sets a driving route to a destination based on the destination setting by the user. In addition, the navigation ECU 134 performs route guidance etc. so that driving along the set driving route becomes easy via an in-vehicle display (not shown) etc. Further, the navigation ECU 134 acquires traffic jam-related information such as the presence or absence of traffic jams, the scale of traffic jams, the presence or absence of disabled vehicles, the presence or absence of construction work, etc. from external facilities and servers that provide traffic information.

[0024] Hereinafter, the driving route set by the navigation ECU134, along with the traffic congestion information related to that driving route and the road information related to that driving route, will be collectively referred to as "driving route information." Road information related to the driving route may include road width, speed limits, and the presence or absence of school zones.

[0025] The control device 100 includes a CPU (Central Processing Unit) 111, RAM (Random Access Memory) 112, ROM (Read Only Memory) 113, auxiliary storage device 114, drive device 115, and communication interface 117 connected by a bus 119, as well as a wired transceiver 125 and a wireless transceiver 126 connected to the communication interface 117.

[0026] The auxiliary storage device 114 is, for example, an HDD (Hard Disk Drive) or an SSD (Solid State Drive), and is a storage device that stores data related to application software, etc.

[0027] The wired transceiver unit 125 includes a transceiver capable of communicating using a wired network 128 based on protocols such as CAN (Controller Area Network) or LIN (Local Interconnect Network). Other in-vehicle electronic equipment 130 is connected to the wired transceiver unit 125. However, some or all of the other in-vehicle electronic equipment 130 may be connected to the bus 119 or to the wireless transceiver unit 126.

[0028] The wireless transceiver 126 is a transceiver capable of communicating using a wireless network. The wireless network may include a mobile phone wireless communication network, the internet, a VPN (Virtual Private Network), a WAN (Wide Area Network), etc. The wireless transceiver 126 may also include a Near Field Communication (NFC) unit, a Bluetooth (registered trademark) communication unit, a Wi-Fi (Wireless-Fidelity) transceiver unit, an infrared transceiver unit, etc.

[0029] The control device 100 may also be connectable to the recording medium 116. The recording medium 116 stores a predetermined program. The program stored in this recording medium 116 is installed in the auxiliary storage device 114 of the control device 100 via the drive device 115. The installed predetermined program becomes executable by the CPU 111 of the control device 100. For example, the recording medium 116 may be a recording medium that records information optically, electrically, or magnetically, such as a CD (Compact Disc)-ROM, flexible disk, or magneto-optical disk, or a semiconductor memory that records information electrically, such as a ROM or flash memory.

[0030] Figure 3 is a functional block diagram schematically showing an example of the functions of the control device 100. Note that some or all of the functions of the control device 100 described below may be implemented by other control devices (for example, the air conditioning control ECU 133 or the navigation ECU 134). Conversely, some or all of the functions of other control devices (for example, the air conditioning control ECU 133 or the navigation ECU 134) may be implemented by the control device 100.

[0031] As shown in Figure 3, the control device 100 includes a driving route information acquisition unit 150, an opening / closing switching request generation unit 151, a vehicle state prediction unit 152, a control mode setting unit 154, and a grill shutter control unit 156. The functions of the driving route information acquisition unit 150 to the grill shutter control unit 156 can be realized by the CPU 111 shown in Figure 2 executing one or more programs in a storage device (for example, the ROM 113 or auxiliary storage device 114 shown in Figure 2).

[0032] The driving route information acquisition unit 150 acquires driving route information from the navigation ECU 134. The driving route information is as described above.

[0033] The open / close switch request generation unit 151 requests the grill shutter 9 to be in the open state when predetermined open request conditions are met. That is, when predetermined open request conditions are met while the grill shutter 9 is in the closed state, the open / close switch request generation unit 151 requests a transition of the grill shutter 9 from the closed state to the open state. Hereinafter, this request will also be simply referred to as the "open switch request".

[0034] The predetermined opening request condition relates to the water temperature in the refrigerant passage 13. Specifically, the predetermined opening request condition may be met when the water temperature in the refrigerant passage 13 exceeds a predetermined threshold Th1. In this case, the opening / closing switching request generation unit 151 determines whether the predetermined opening request condition has been met based on sensor information from the water temperature sensor 131. The predetermined threshold Th1 may be constant. The predetermined threshold Th1 is arbitrary, but for example, it may be around 50 degrees.

[0035] Furthermore, when the open / close request generation unit 151 generates an open request, it then determines whether a predetermined close request condition is met. If the predetermined close request condition is met, it requests the grill shutter 9 to be closed. The predetermined close request condition may be met when the water temperature in the refrigerant passage 13 falls below a predetermined threshold Th2, for example. In this case, the predetermined threshold Th2 may be less than or equal to a predetermined threshold Th1.

[0036] The vehicle condition prediction unit 152 predicts the future state of the vehicle. That is, the vehicle condition prediction unit 152 predicts the state of the vehicle from the present moment onward. The vehicle state may include vehicle speed, water temperature (water temperature in the refrigerant passage 13), etc.

[0037] In this embodiment, the vehicle state prediction unit 152 includes a high-speed driving condition prediction unit 1522, a water temperature prediction unit 1524, and an open switch request occurrence prediction unit 1526.

[0038] The high-speed driving condition prediction unit 1522 predicts whether or not a high-speed driving condition (an example of a second condition) will occur in the future state of the vehicle. A high-speed driving condition may be a condition in which the vehicle speed remains at or above a predetermined vehicle speed Vth2 (an example of a second vehicle speed) for a predetermined period of time or longer. In this case, the predetermined vehicle speed Vth2 is arbitrary, but the work P' (= 1 / 2 × ρ × Cd' × A × V) caused by air resistance when the vehicle is running with the grill shutter 9 open is also important. 2 ) may be adapted considering the following. For example, the predetermined vehicle speed Vth2 is the work P (= 1 / 2 × ρ × Cd × A × V) caused by the air resistance when the vehicle is running with the grill shutter 9 closed. 2 The vehicle speed may be such that the difference ΔP (= P'-P) between the temperature and the work P' is greater than or equal to a predetermined threshold ΔPth. In this case, ρ is the density of air, Cd' is the Cd value when the grill shutter 9 is open, Cd is the Cd value when the grill shutter 9 is closed, A is the projected area of ​​the vehicle body, and V is the vehicle speed. Since the values ​​of parameters such as A differ for each vehicle model, the predetermined vehicle speed Vth2 may differ for each vehicle model. The predetermined threshold ΔPth is arbitrary, but may be set to a value significantly larger than the work related to the increased cooling capacity by opening the grill shutter 9 (for example, the energy that can be taken from the water in the refrigerant passage 13).

[0039] The high-speed driving situation prediction unit 1522 may predict the presence or absence of high-speed driving based on the driving route information. By utilizing the driving route information, the prediction accuracy can be improved. For example, the high-speed driving situation prediction unit 1522 may predict the presence of high-speed driving if the driving route includes expressways or roads with relatively high speed limits. In this case, the high-speed driving situation may also be predicted if the driving route includes expressways, etc., and the section excluding congested areas is of a certain length or longer. Also, from a similar viewpoint, the high-speed driving situation prediction unit 1522 may predict the presence of high-speed driving if the driving route includes a section where the average vehicle speed is equal to or greater than a predetermined vehicle speed Vth2.

[0040] The water temperature prediction unit 1524 predicts the water temperature in the refrigerant passage 13. The water temperature prediction unit 1524 may predict the water temperature in the refrigerant passage 13 only if the high-speed driving condition prediction unit 1522 predicts that high-speed driving conditions exist. In this case, if the high-speed driving condition prediction unit 1522 predicts that high-speed driving conditions exist, the water temperature prediction unit 1524 may predict the water temperature in the refrigerant passage 13 under the predicted high-speed driving conditions. At this time, the water temperature prediction unit 1524 may predict the water temperature in the refrigerant passage 13 under the predicted high-speed driving conditions by assuming that the grill shutter 9 is in a closed state.

[0041] The water temperature in the refrigerant passage 13 may be predicted by adding the calculated future temperature rise ΔT to the current water temperature in the refrigerant passage 13 (sensor information from the water temperature sensor 131). The method for calculating the future temperature rise ΔT is arbitrary, but for example, it may be as follows. ΔT = Loss / Cw Here, Loss is the total loss of the electric motor 8 and power supply system 7 related to the refrigerant path 13 from the present time to the predicted time, and may be calculated based on the rotational speed and torque predicted to be realized at each section (location) of the travel route. In this case, the driving mode (rotational speed and torque) of the electric motor 8 will be predicted based on the travel route information. Cw is the heat capacity of the water in the refrigerant path 13. In other examples, the heat capacity of the piping related to the refrigerant path 13 may be considered in order to improve prediction accuracy. By performing such water temperature prediction, the prediction accuracy of the open switching request generation prediction unit 1526, which will be described later, can be improved.

[0042] The open-switching request generation prediction unit 1526 predicts, based on the prediction results from the water temperature prediction unit 1524, whether or not an open-switching request will be generated by the open / closed request generation unit 151 under the high-speed driving conditions predicted by the high-speed driving conditions prediction unit 1522. For example, the open-switching request generation prediction unit 1526 may predict that an open-switching request will be generated when the water temperature predicted by the water temperature prediction unit 1524 exceeds a predetermined threshold Th1.

[0043] Furthermore, if the open-switching request prediction unit 1526 predicts that an open-switching request will occur during high-speed driving conditions, it may also predict whether the duration of the open state of the grill shutter 9, which is realized in response to the open-switching request, will be longer than a predetermined time.

[0044] The control mode setting unit 154 sets the control mode to the first mode when the high-speed driving condition prediction unit 1522 does not predict that there will be high-speed driving conditions. The control mode setting unit 154 also sets the control mode to the second mode when the high-speed driving condition prediction unit 1522 predicts that there will be high-speed driving conditions, and the open-switching request occurrence prediction unit 1526 predicts that an open-switching request will occur in the high-speed driving conditions. Alternatively, the control mode setting unit 154 may set the control mode to the second mode when the high-speed driving condition prediction unit 1522 predicts that there will be high-speed driving conditions, and it is also predicted that the duration of the open state of the grill shutter 9 realized in response to the open-switching request will be longer than a predetermined time.

[0045] Regardless of whether the control mode is the first mode or the second mode, the grill shutter control unit 156 controls the open / closed state of the grill shutter 9 in response to a request (such as an open switch request) from the open / close switch request generation unit 151.

[0046] When the control mode is set to the second mode, the grill shutter control unit 156 switches the grill shutter 9 from the closed state to the open state in low-speed driving conditions (an example of the first condition), regardless of whether or not there is an open switching request from the open / close switching request generation unit 151. In other words, when the control mode is set to the second mode, the grill shutter control unit 156 switches the grill shutter 9 from the closed state to the open state in low-speed driving conditions, even if no open switching request is generated by the open / close switching request generation unit 151. Hereinafter, this control, in which the grill shutter 9 is kept open in low-speed driving conditions when the control mode is set to the second mode, will also be referred to as "pre-cooling control".

[0047] A low-speed driving situation may be a situation in which the vehicle speed remains below a predetermined vehicle speed Vth1 (an example of the first vehicle speed) for a predetermined period of time or longer. The predetermined vehicle speed Vth1 may be less than or equal to the predetermined vehicle speed Vth2 mentioned above.

[0048] When the grill shutter control unit 156 starts pre-cooling control, it may continue pre-cooling control until predetermined termination conditions are met. The predetermined termination conditions are arbitrary, but may be met, for example, when a certain amount of time has elapsed, when the vehicle speed reaches a predetermined vehicle speed Vth2 or higher (i.e., when high-speed driving conditions are reached), or when the water temperature in the refrigerant passage 13 falls below a predetermined threshold Th3. In this case, the predetermined threshold Th3 may be less than or equal to the predetermined threshold Th1 described above, for example, it may be the same as the predetermined threshold Th2 described above, or it may be a temperature slightly higher than the ambient temperature.

[0049] In this way, according to this embodiment, by performing pre-cooling control, it can be expected that the frequency and time at which an open switching request is generated by the open / close switching request generation unit 151 in the high-speed driving conditions that subsequently occur as predicted will be reduced. In other words, it is possible to prevent the inconvenience caused by forming an open state of the grill shutter 9 in high-speed driving conditions (deterioration of fuel efficiency due to deterioration of aerodynamic characteristics). As a result, according to this embodiment, it is possible to achieve both improved aerodynamic characteristics and ensured cooling performance with respect to the control of the grill shutter 9.

[0050] Figure 4 is an explanatory diagram of the effects of this embodiment. In Figure 4, the vehicle speed, water temperature (water temperature in the refrigerant passage 13), control mode, and the open / closed state of the grill shutter 9 are shown in time series (waveforms) from top to bottom. In Figure 4, the dotted line time series waveform 400 is shown as an example of the characteristics of the comparative example. Note that the parts other than the dotted line are the same for this embodiment and the comparative example.

[0051] In the example shown in Figure 4, at time t1, which corresponds to the time when the driving route is set, the control mode is switched from the first mode to the second mode because the generation of an open switching request in high-speed driving conditions (see time t3) is predicted. Note that the initial mode when the vehicle starts up may be the first mode. The vehicle speed indicates low-speed driving conditions until around time t2. At this time, the water temperature is below a predetermined threshold Th1, but the pre-cooling control described above is executed. That is, the open state of the grill shutter 9 is achieved from time t1. Subsequently, at time t2, the vehicle speed becomes a high-speed driving condition of a predetermined vehicle speed Vth2 or higher, and the grill shutter 9 is closed. In this way, in this embodiment, pre-cooling control is executed from time t1 to time t2. In the comparative example, high-speed driving conditions are reached without such pre-cooling control being executed. In the comparative example, the water temperature exceeds the predetermined threshold Th1 from time t3. In contrast, in this embodiment, the water temperature at time t2 is lower than in the comparative example due to the pre-cooling control from time t1 to time t2. Therefore, in this embodiment, the time t4 at which the predetermined threshold Th1 is exceeded is delayed by time Δt compared to time t3. As a result, at time Δt, high-speed driving is possible with the grill shutter 9 in the closed state, thereby reducing driving resistance (and consequently improving fuel efficiency).

[0052] Figure 5 is a schematic flowchart showing an example of a process performed by the control device 100 of this embodiment.

[0053] In step S500, the control device 100 determines whether the vehicle is currently driving at a low speed based on the vehicle speed information from the vehicle speed sensor 25. If the determination result is "YES", the process proceeds to step S502; otherwise, the process ends.

[0054] In step S502, the control device 100 determines whether the difference between the water temperature and the ambient temperature is greater than a predetermined value, based on the sensor information from the water temperature sensor 131 and the sensor information from the ambient temperature sensor 24. The predetermined value is set to a value that allows a certain amount of heat to be released from the water in the refrigerant passage 13. If the determination result is "YES", the process proceeds to step S504; otherwise, the process terminates.

[0055] In step S504, the control device 100 acquires the travel route information. The travel route information may be as described above.

[0056] In step S506, the control device 100 predicts the water temperature in the refrigerant passage 13 and the driving conditions on the driving route (whether or not there are high-speed driving conditions). These prediction methods may be as described above.

[0057] In step S508, the control device 100 determines, based on the prediction result from step S506, whether or not high-speed driving conditions are occurring at the time the water temperature reaches a predetermined threshold Th1. If the determination result is "YES", the process proceeds to step S510; otherwise, the process terminates.

[0058] In step S510, the control device 100 generates an open switching request and executes pre-cooling control. Once pre-cooling control is started, it may be continued until the difference between the water temperature and the ambient temperature (see step S502) falls below a predetermined value.

[0059] In this way, according to the process shown in Figure 5, when high-speed driving conditions are predicted to occur at the same time that the water temperature reaches a predetermined threshold Th1 during low-speed driving, pre-cooling control can be started. As a result, as described above with reference to Figure 4, if high-speed driving conditions occur as predicted thereafter, the time during which the grill shutter 9 can be kept closed during those high-speed driving conditions can be extended, thereby reducing driving resistance (and consequently improving fuel efficiency).

[0060] Although each embodiment has been described in detail above, the invention is not limited to any particular embodiment, and various modifications and changes are possible within the scope described in the claims. Furthermore, it is possible to combine all or more of the components of the embodiments described above.

[0061] For example, in the embodiment described above, the control mode setting unit 154 sets the control mode to the second mode when it is predicted that there will be high-speed driving conditions and that an open-switching request will occur in those high-speed driving conditions, but it is not limited to this. For example, if the control mode setting unit 154 predicts that there will be high-speed driving conditions based on the driving route information, it may set the control mode to the second mode regardless of whether or not an open-switching request is predicted to occur in those high-speed driving conditions. In this case, the open-switching request occurrence prediction unit 1526 may be omitted. [Explanation of Symbols]

[0062] 9 Grill shutter, 13 Refrigerant passage (water passage), 100 Control device (vehicle control device), 131 Water temperature sensor (temperature sensor), 151 Open / close switching request generation unit (request generation unit), 152 Vehicle state prediction unit (prediction unit), 156 Grill shutter control unit

Claims

1. A grill shutter control unit that switches the open / closed state of the grill shutter provided in the opening at the front of the vehicle, It includes a prediction unit that predicts the future state of the vehicle based on information related to the vehicle's future travel route, The grill shutter control unit is a vehicle control device that, based on the prediction result from the prediction unit, switches the grill shutter from a closed state to an open state in a first situation where the vehicle speed is less than a first vehicle speed.

2. The system further includes a request generation unit that generates a switching request to switch the grill shutter from a closed state to an open state based on sensor information from a temperature sensor that detects the temperature of the cooling water in a water channel that can be cooled by the airflow taken in through the open grill shutter. The prediction unit predicts whether the request generation unit will generate the switching request under the second condition where the vehicle speed is greater than or equal to the second vehicle speed which is greater than or equal to the first vehicle speed. The vehicle control device according to claim 1, wherein the grill shutter control unit switches the grill shutter from a closed state to an open state when the prediction unit predicts that the switching request will be generated under the second condition, even if the request generation unit has not generated the switching request under the first condition prior to the second condition.

3. The vehicle control device according to claim 2, wherein the prediction unit predicts whether or not the request generation unit will generate the switching request under the second condition by predicting the temperature of the cooling water.

4. The vehicle control device according to claim 3, wherein the prediction unit predicts the presence or absence of the second condition and the temperature of the cooling water based on the information relating to the driving route.

5. A grille shutter control process that switches the open / closed state of the grille shutter provided in the opening at the front of the vehicle, The computer performs a predictive process to forecast the future state of the vehicle. The grill shutter control process is a program that, based on the prediction result obtained by the prediction process, switches the grill shutter from a closed state to an open state in a first situation where the vehicle speed is less than or equal to a first vehicle speed.

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