Automotive air conditioning control

Abstract

The aim is to ensure continued air conditioning safety for as long as possible when people are inside a parked vehicle for extended periods. [Solution] When it is detected that there is an occupant inside the vehicle while parked, the condition value for the power generation start SOC is lowered to an extremely low SOC, which is lower than the predetermined power generation start SOC value, the air conditioning system 15 is started without starting the engine 12, and the following (a)-(c) are repeated. (a) When the State of Charge (SOC) of the battery 13 reaches an extremely low SOC, the air conditioning unit 15 is shut down. (b) When the interior temperature of the vehicle reaches a range outside the predetermined range, the engine 12 is started, the air conditioning system 15 is started, and the battery 13 is charged. (c) Once the State of Charge (SOC) of battery 13 recovers to the variable SOC at the end of power generation, the engine 12 is stopped and the air conditioning system 15 continues to operate using power from battery 13.

Description

Technical Field

[0001] This invention relates to the air conditioning control of automobiles.

Background Art

[0002] With the intensification of various climate changes including recent global warming, the importance of air conditioning in automobiles has increased and it has become an essential element for maintaining the life of passengers. During driving, the engine or motor is operating and charging is also carried out using regenerative energy, so it is natural to keep the air conditioning running continuously. However, when the engine stops during parking, the air conditioning basically stops. In the hot summer, staying in a car without air conditioning for a long time poses a risk of heatstroke. Conversely, in the cold winter, staying in a car without a heater for a long time poses a risk of hypothermia. As a situation where such risks are feared, incidents where infants are left unattended in parked cars have become a social problem. There are also cases where long-distance transport drivers take breaks in parked cars. Therefore, it is required to maintain temperature control as much as possible even when there are people in the parked car.

[0003] In Patent Document 1, a technique has been proposed to start the engine in order to operate the air conditioner when it is detected that infants or the like have been left unattended in the car.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, simply starting the engine and running the air conditioner would deplete the fuel supply just enough to run the engine, preventing further charging or power generation, and ultimately making it impossible to maintain a consistent temperature for extended periods. Furthermore, especially when parked in environments where air circulation is poor, such as narrow indoor parking lots, continuously running the engine could increase the carbon monoxide concentration inside the vehicle.

[0006] Therefore, the purpose of this invention is to ensure air conditioning safety for as long as possible when people are inside a parked car for extended periods. [Means for solving the problem]

[0007] This invention is As a first solution for a vehicle including an engine, a battery, an in-vehicle detection device for detecting occupants inside the vehicle, and an air conditioning system for conditioned the interior of the vehicle, The control device that controls the vehicle is The system performs charging control such as starting the engine to charge the battery when the battery's State of Charge (SOC) falls below a predetermined power generation start SOC, and stopping the engine when the battery is charged to a predetermined power generation end SOC. Under predetermined conditions, when the in-vehicle detection device detects that there is an occupant inside the vehicle while it is parked, The condition value for the power generation start SOC is lowered to an extremely low SOC, which is lower than the default power generation start SOC value, and the air conditioning system is started without starting the engine. The above problem was solved by a first solution that cyclically performs the controls described in (a)-(c) below in the order listed. (a) When the State of Charge (SOC) of the battery reaches the extremely low SOC, the air conditioning system is shut off. (b) When the interior temperature of the vehicle reaches outside the predetermined range, the engine is started, the air conditioning system is started, and the battery is charged. (c) When the State of Charge (SOC) of the battery recovers to the State of Charge (SOC) of the end of power generation, the engine is stopped and the air conditioning system continues to operate using power from the battery.

[0008] Furthermore, in the first solution, this invention It has an external detection device that detects whether the vehicle's parking location is an indoor space or not. The control device can employ a second solution, which involves lowering the power generation termination SOC value, if it detects that the space is indoors.

[0009] Furthermore, in the first or second solution, As a change in the condition value performed under the aforementioned predetermined conditions, further, The condition value for the power generation termination SOC is lowered to a variable power generation termination SOC that is lower than the default power generation termination SOC value. The switching of the control in (c) above is performed by the variable SOC at the end of power generation. A third solution can be adopted.

[0010] Furthermore, in the third solution, this invention The vehicle has an external detection device that detects the degree of narrowness of the indoor space at the parking location. The value of the variable SOC at the end of power generation is set lower according to the detected narrowness of the indoor space. A fourth solution can be adopted.

[0011] Furthermore, in the first to fourth solutions of this invention, Under the aforementioned predetermined conditions, a fifth solution can be adopted, which involves operating the air conditioning system with a power-saving setting compared to the default. [Effects of the Invention]

[0012] This invention allows for complete control of the air conditioning system only when necessary for the cabin temperature, while reducing the need for engine starting by setting a lower SOC (State of Charge) limit than usual. This enables the maintenance of a safe cabin environment for a longer period of time with less electricity and fuel than conventional methods. [Brief explanation of the drawing]

[0013] [Figure 1]Functional block diagram showing an embodiment of a vehicle according to the present invention [Figure 2] Image diagram of the transition for maintaining the SOC during normal charging control by the vehicle control device according to the present invention [Figure 3] Example diagram of the flow for continuing charging control under predetermined conditions of the vehicle according to the present invention [Figure 4] Image diagram of the transition for maintaining the SOC while performing air - conditioning control when the vehicle control device according to the present invention performs charging control under predetermined conditions

Embodiments for Carrying Out the Invention

[0014] Hereinafter, embodiments of the present invention will be described. The present invention is a vehicle 10 that performs air - conditioning control. An example of the embodiment is shown in FIG. 1. This vehicle 10 includes a control device 11, an engine 12, a battery 13, an in - vehicle detection device 14 that detects passengers existing in the interior of the vehicle 10 (hereinafter abbreviated as "in - vehicle space R"), and an air - conditioning device 15 that air - conditions the in - vehicle space. Further, it has a power generation device 16 that generates electricity by the engine 12 and can charge the battery 13. The in - vehicle detection device 14 and the air - conditioning device 15 can operate with power from the battery 13. Furthermore, it is preferable to have an out - vehicle detection device 20 that detects whether the parking position is an indoor space. It is more preferable that this out - vehicle detection device 20 can detect the degree of narrowness of the indoor space.

[0015] This vehicle 10 may be an engine vehicle driven only by the engine 12 or a hybrid vehicle having a motor 18 together with the engine 12. In the case of a hybrid vehicle, it may be a plug - in hybrid vehicle (PHEV) that is not only charged by the power generated by the engine 12 but also has external charging that can be charged from the outside or external power supply that can supply power to the outside. In the following description, a hybrid vehicle is taken as an example, but the present invention is not limited to this.

[0016] The control device 11 used in this invention may be configured as a part of the function of an ECU (Electronic Control Unit) responsible for controlling the vehicle 10 itself, or may be configured as an attached hardware separate from the ECU. When the control device 11 is configured as a part of the ECU, it is easy to combine with the hardware used for normal driving and is easy to mount.

[0017] Regardless of the configuration form, the control device 11 has an arithmetic unit, a temporary memory used for arithmetic, and a non-temporary computer-readable storage medium for storing programs and data. Further, the control device 11 has an interface for exchanging data and signals with each part constituting the vehicle 10.

[0018] The vehicle 10 has a battery 14 capable of supplying electricity to operate the devices of the vehicle 10 including the air conditioner 15. It may be a 12V system battery using a lead-acid battery, or a large-capacity secondary battery capable of charging and supplying the power used for driving the motor 18. In the figure, it is collectively described as one battery 13, but an example having both a 12V system battery and a large-capacity secondary battery is described. Examples of this large-capacity secondary battery include a nickel-metal hydride battery, a lithium-ion battery, a sodium-ion battery, and the like.

[0019] It is necessary for the control device 11 to be able to acquire the state of charge (SOC) of the battery 13. However, since it is difficult to directly measure the SOC of the battery 13 itself, it is obtained indirectly based on other values that can be easily measured. Preferably, the SOC can be obtained by referring to the properties of the battery 13 mainly from the voltage drop due to the voltage and current of the battery 13. As an embodiment, the SOC may be obtained on the battery 13 side and transmitted to the control device 11. As another embodiment, the voltage and current values of the battery 13 may be transmitted to the control device 11 and the control device 11 may calculate the SOC.

[0020] Vehicle 10 has an in-vehicle detection device 14 that detects the presence or absence of passengers H inside the vehicle R. Passengers H include not only those in the driver's seat, but also those in the passenger seat and rear seats. Preferably, it should also be able to detect when a child is in a gap that a passenger H could fit into. The detection method is not particularly limited, but it is preferable that it is not likely to mistake mere luggage for a person. For example, this could include a weight sensor (high-precision is desirable), an infrared sensor, image recognition from an in-vehicle camera, voice recognition from an in-vehicle microphone, or a combination of these.

[0021] Vehicle 10 has an air conditioning system 15 that can be automatically turned on and off by a control device 11. The air conditioning system 15 adjusts the temperature inside the vehicle R to a comfortable temperature for the passengers H, and it is necessary that it has at least the function of a cooler. If vehicle 10 is intended for use in snowy or cold regions, it is preferable that it has both the function of a cooler and a heater.

[0022] The vehicle 10 has a power generator 16 that can generate electricity by driving the engine 12. The electricity generated by the power generator 16 can charge the battery 13. Alternatively, there may be an embodiment in which the motor 18 can be driven directly by the electricity generated by the power generator 16 without going through the battery 13.

[0023] Vehicle 10 has a thermometer 17 that measures the temperature inside the vehicle R (hereinafter referred to as "interior temperature"). The installation location is not particularly limited, but it is desirable to place it in a location that is not exposed to direct sunlight so that the difference between the actual temperature and the measured value is small. The value of the interior temperature measured by the thermometer 17 is transmitted to the control device 11.

[0024] Vehicle 10 has a motor 18 that drives the wheels 19. However, this invention can also be used in a gasoline vehicle that does not have a motor 18 and drives the wheels 19 with an engine 12.

[0025] Vehicle 10 has an external detection device 20 that can detect whether or not the vehicle 10's parking location is an indoor space. Preferably, it can detect not only whether or not it is an indoor space, but also a value that can quantify the narrowness of the surrounding space. The external detection device 20 does not need to be a standalone device; it is preferable that it can perform the above detection and quantification using data from other devices with different functions. Specifically, it may be implemented as a detection device that can directly measure the distance to surrounding walls, etc., such as an ultrasonic sensor or an infrared sensor, or as estimation by image recognition of images of the outside of the vehicle from an external camera, or as inference using indirect data such as the reception status using a GPS signal receiver. In this case, the estimation may be performed by a control device 11 that receives the images or data. When vehicle 10 is parked in an indoor space, the oxygen concentration tends to decrease and the concentrations of carbon dioxide and carbon monoxide tend to increase compared to when it is parked in an outdoor parking lot. This tendency is even more pronounced when the indoor space is narrow, such as in a multi-story parking garage. The more the parking location is an indoor space and the narrower the surrounding space, the less opportunity there is to start the engine, thus reducing the possibility of carbon monoxide poisoning. Furthermore, if there is a roof, the rise in interior temperature due to sunlight will be slower than in an outdoor parking lot, allowing for more energy-efficient solutions.

[0026] The control device 11, by default, performs charging control that starts the engine 12 and charges the battery 13 with the power generator 16 when the battery 13's State of Charge (SOC) falls below a predetermined power generation start SOC, and stops charging when the battery 13 is charged to a predetermined power generation end SOC. Figure 2 shows an image of the changes in the battery 13's SOC as it repeatedly charges and discharges. This power generation start SOC is the line at which the SOC can be treated as having sufficient power to start the engine 12, motor 18, and air conditioning unit 15. If the SOC falls below the power generation start SOC, problems may occur in starting the equipment, so the control starts charging to maintain an SOC above this line. Both the power generation start SOC and the power generation end SOC are different values ​​depending on the capacity and type of battery 13, the properties of the vehicle 10, etc. As an example, the power generation start SOC is generally set to around 20%. The power generation end SOC is generally set to around 50%.

[0027] In the vehicle 10 according to this invention, under predetermined conditions in which the in-vehicle detection device 14 detects the presence of an occupant H inside the vehicle R while parked, the air conditioning system 15 performs specific continuous control to maintain the interior temperature within an appropriate range for an extended period of time. Here, predetermined conditions refer to conditions that go beyond the limit that can be considered merely the time it takes for the occupant H to get out of the vehicle immediately after parking, and are judged to strongly suggest the possibility of abandonment, napping, or a long rest after parking. The above predetermined conditions should be appropriately set for each use, type of vehicle 10, and other conditions. For example, the conditions for determining abandonment may differ between a private car and a minibus. Also, the conditions for determining rest time may differ between a passenger car and a truck. As an example of how to set the above predetermined conditions, the control device 11 may determine that the conditions are met after a predetermined time (for example, about 10 minutes) has elapsed since the vehicle's READY-OFF operation and key lock were detected. If the key lock is not engaged, it is assumed that the driver has a high probability of intending to return quickly, and the risk of abandonment is low. Of course, the above-mentioned conditions do not have to be limited to just one. By setting additional conditions and determining whether a child has been left behind or is on a break when those additional conditions are met, further risk reduction can be achieved.

[0028] The continuous control of the vehicle 10 by the control device 11 will be explained below, along with the flow shown in Figure 3. First, it is confirmed that the vehicle 10 is parked (S101). Specifically, it can be determined that the vehicle is parked when the shift lever is put into P and the ignition is turned off, but other conditions may also be used. Once parked, the in-vehicle detection device 14 checks whether or not there is an occupant H inside the vehicle R (S102). If occupant H is no longer detected (S102 → No), there is no need to maintain the interior temperature, so the process ends there (S103). At the end of the process, it is preferable to return the condition value changed by S111, which will be described later, to its default value.

[0029] If an occupant H is detected inside the vehicle R (S102 → Yes), the system waits until predetermined conditions are met to determine that the occupant has been left behind or has been inside the vehicle for an extended period (S104 → No). These predetermined conditions can be, for example, the elapsed time since the vehicle was parked (S101). Other conditions may also be set.

[0030] Once the above predetermined conditions are met (S104 → Yes), control for maintaining continuous air conditioning is initiated. First, the condition values ​​are changed from the default values ​​in the normally performed charge control (S111). The condition value for the power generation start SOC is lowered to an extremely low SOC, which is lower than the default power generation start SOC value. Figure 4 shows an image of this value change. For example, if the power generation start SOC is 20%, one embodiment is conceivable in which it is lowered to 5% as the extremely low SOC. This extremely low SOC is an SOC close to the limit in which the engine 12 and air conditioning unit 15 can be started. It is a value closer to the actual limit than the default power generation start SOC, and if it falls below this extremely low SOC, it becomes difficult to start the engine 12, and there is a high possibility that the charge control cannot be sustained. In other words, the control is changed to reduce the opportunities to start the engine up to near the limit, and to maintain the interior temperature of the vehicle by not starting the engine 12 for a longer period of time and suppressing fuel consumption.

[0031] Furthermore, the condition value for the power generation termination SOC is lowered to a variable power generation termination SOC that is lower than the default power generation termination SOC value (S111). This change in value is also shown in Figure 4. This variable power generation termination SOC is a value that ensures the power necessary to maintain the temperature environment while reducing the surplus and preventing the engine 12 from continuing to operate for longer than necessary.

[0032] If the door remains closed, the air conditioning unit 15 is operated using power from the battery 13 while the engine 12 remains stopped (S112). At this point, it is preferable to switch whether the air conditioning unit 15 operates as a cooler or a heater based on the value of the thermometer 17. Furthermore, it is desirable to operate the air conditioning unit 15 in a power-saving mode that consumes less power than when the vehicle 10 is in motion. In particular, if the vehicle external detection device 20 confirms that the parking location is indoors, the temperature rise and fall will be more gradual than in environments such as scorching sun or blizzards, so it is possible to maintain the indoor temperature sufficiently with a power-saving operation compared to the power mode used when driving outdoors. Specifically, power-saving modes include setting the airflow to low and setting a small difference between the temperature measured by the thermometer 17 and the set temperature of the air conditioning unit.

[0033] At this point in the processing flow, a check is performed regarding the opening and closing of the door (S113). If the door is opened (S113 → Yes), it is presumed that if the person was left behind, someone outside noticed and came to rescue them; if they were resting or napping inside, it is presumed that they have finished and are getting out of the vehicle. Information regarding the opening and closing of the door can be obtained using the functions that are generally available in automobiles.

[0034] Note that the order in which steps S111 to S113 are performed does not matter.

[0035] In this configuration, with the engine 12 stopped, the air conditioning system 15 is operated in power-saving mode using power from the battery 13. This operation continues until the State of Charge (SOC) of the battery 13 reaches the extremely low SOC lowered in S111 (S114 → No). This allows for a longer time before starting the engine 12, thereby reducing the opportunity to start the engine 12. The change in SOC during this period corresponds to the decreasing portion with a negative slope in Figure 4.

[0036] If the State of Charge (SOC) of battery 13 reaches an extremely low SOC (a: S114 → Yes), the air conditioning system 15 is temporarily stopped (a: S115) because any further decrease in SOC would interfere with starting the engine 12. Although minimal devices such as the control unit 11 operate when the air conditioning system 15 is stopped, the decrease in SOC is extremely suppressed. The SOC during this period corresponds to the part in Figure 4 where there is no slope and the SOC is maintained. The control unit 11 continues to monitor the change in the interior temperature in this state (S116 → No). If the interior temperature falls outside the predetermined range (b: S116 → Yes), the engine 12 is started to begin charging the battery 13 and the air conditioning system 15 is activated (b: S117) because continuing to stop the air conditioning system 15 any further could have adverse effects on passenger H. Here, "outside the predetermined range" refers to the temperature range that is comfortable for passenger H, and is undesirable if it exceeds the upper limit or falls below the lower limit. However, since the passenger H's condition varies depending on the season, it may be a value that can be changed according to the season, latitude, and other conditions, rather than a fixed value.

[0037] The air conditioning system 15 is operated while charging is performed by the engine 12, and this continues until the SOC recovers to the variable SOC at the end of power generation (S118 → No). The change in SOC during this time corresponds to the part where the slope is positive and increasing in Figure 4. Once the SOC recovers to the variable SOC at the end of power generation (c: S118 → Yes), the engine 12 is stopped (c: S119). By stopping the recovery to the variable SOC at the end of power generation rather than continuing to charge unnecessarily, excessive operation of the engine 13 is suppressed and fuel consumption is reduced. At this stage, the air conditioning system 15 is operating, and the SOC of the battery 13 gradually decreases.

[0038] The control device 11 then repeats this cycle (a→b→c→a→...). If the door is opened during this time, it assumes that the abandonment has been resolved or the break is over, and resets the charging control condition value to terminate the control (S103).

[0039] If the external detection device 20 determines that the parking location of the vehicle 10 is an indoor space, the control device 11 lowers the variable State of Charge (SOC) at which power generation ends. This increases the number of engine starts, but shortens the engine operating time. A short charge will allow the air conditioner to be used for a while, but since the temperature change per unit of time is gradual indoors, it is possible to cope to some extent even if the air conditioner is not running continuously. This reduces the operating time of the engine and thus reduces the amount of carbon dioxide emitted.

[0040] Furthermore, if the external detection device 20 can detect the degree of narrowness of the indoor space at the parking position of the vehicle 10, the value of the variable SOC at the end of power generation should be set lower according to the detected narrowness of the indoor space. The more likely the carbon dioxide concentration is to increase in a space, the lower the value of the variable SOC at the end of power generation should be set to make it easier to suppress the amount of carbon dioxide emitted. The setting can be done in stages or continuously. For example, if the default SOC at the end of power generation is 50%, it can be set to 40% in an indoor parking lot with a roof but open surroundings, to 35% if there is a roof and the surroundings allow for free opening and closing of doors but two sides are walled, to 30% if care is needed when opening and closing doors and two or more sides are walled, and to 25% if the ceiling height is within +20cm of the height of the vehicle 10.

[0041] Furthermore, carbon dioxide and carbon monoxide levels tend to increase not only in parking lots but also when parking in snow. Therefore, it is advisable to assess the area surrounded by snow in a manner similar to the narrowness of an indoor space and apply the same settings as described above. [Explanation of Symbols]

[0042] 10 vehicles 11 Control device 12 Engines 13 batteries 14. In-vehicle detection device 15 Air conditioner 16. Power generation equipment 17 Thermometer 18 motors 19 wheels 20 External detection device

Claims

1. Regarding a vehicle that includes an engine, a battery, an in-vehicle detection device for detecting occupants inside the vehicle, and an air conditioning system for conditioned the interior of the vehicle, The control device that controls the aforementioned vehicle is The system performs charging control such as starting the engine to charge the battery when the battery's State of Charge (SOC) falls below a predetermined power generation start SOC, and stopping the engine when the battery is charged to a predetermined power generation end SOC. Under predetermined conditions, when the in-vehicle detection device detects that there is an occupant inside the vehicle while it is parked, The condition value for the power generation start SOC is lowered to an extremely low SOC, which is lower than the predetermined power generation start SOC value, and the air conditioning system is started without starting the engine. A vehicle that performs the following controls (a)-(c) in a cyclical manner in the order listed. (a) When the State of Condition (SOC) of the battery reaches the extremely low SOC, the air conditioning system is shut off. (b) When the interior temperature of the vehicle reaches outside the predetermined range, the engine is started, the air conditioning system is started, and the battery is charged. (c) When the State of Charge (SOC) of the battery recovers to the State of Charge (SOC) of the end of power generation, the engine is stopped and the air conditioning system continues to operate using power from the battery.

2. The vehicle has an external detection device that detects whether the parking location of the vehicle is an indoor space or not. The vehicle according to claim 1, wherein the control device reduces the value of the power generation termination SOC when the space is indoors.

3. As a change in the condition value performed under the aforementioned predetermined conditions, further, The condition value for the power generation termination SOC is lowered to a variable power generation termination SOC that is lower than the default power generation termination SOC value. The switching of the control in (c) above is performed by the variable SOC for power generation termination. The vehicle according to claim 1.

4. The vehicle has an external detection device that detects the degree of narrowness of the indoor space at the parking location. The value of the variable SOC at the end of power generation is set to a lower value according to the detected narrowness of the indoor space. The vehicle according to claim 3.

5. Under the aforementioned predetermined conditions, the air conditioning system will be operated with a power-saving setting that is lower than the default setting. A vehicle according to any one of claims 1 to 4.

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