JP2006278045A - Battery temperature estimating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately estimate the battery temperature of a vehicular battery in a trunk by an inexpensive device structure. <P>SOLUTION: When the value of solar radiation in a vehicle interior 22, which is detected by a sunshine sensor 1, is smaller than a prescribed value, battery temperatures detected by an in-car sensor 2 are used as the temperatures of a battery 11 and a high voltage battery 12, and when the value of solar radiation in the vehicle interior is not less than the prescribed value, a correction value ▵T forming a temperature difference between interior temperatures detected by the in-car sensor 2 and a temperature in the trunk 21 is estimated, and the estimated correction value ▵T is added to the interior temperature detected by the in-car sensor 2, or is deducted from the interior temperature depending on the operating condition of an air conditioner 15. Thereby, the temperatures of the battery 11 and the high voltage battery 12 are estimated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to charging of a battery mounted on a vehicle, and more particularly to a battery temperature estimation device that estimates a battery temperature required for appropriate charging of a battery mounted on a vehicle.

  In general, a rechargeable battery, which is a rechargeable battery (hereinafter referred to simply as a battery), has an optimum temperature condition for charging, and is charged in an environment where the temperature is low. It is difficult to charge in an environment where the temperature is high. When such a battery is charged at a low voltage under a low temperature environment and at a high voltage under a high temperature environment, deterioration of the battery can be prevented.

  Therefore, a method has been devised that measures the battery temperature so that the battery mounted on the vehicle can be charged under appropriate conditions, and controls the battery to be charged with an appropriate voltage based on the measured battery temperature. Yes.

  As a battery temperature acquisition method necessary for performing such charge control on the battery, a method of directly detecting using a temperature detection means provided in the battery and a temperature detection provided in the vicinity of the battery There is a method of obtaining indirectly from the temperature detected by the means by taking into account various conditions such as the installation position of the temperature detection means and the installation position of the battery.

  In the method of directly obtaining the battery temperature, it is necessary to newly provide a dedicated temperature detection means for detecting the battery temperature, which causes a problem that the cost increases.

On the other hand, in the method of indirectly obtaining the battery temperature, a dedicated temperature detecting means for detecting the battery temperature is not required, and the battery temperature is calculated from the value detected by the temperature detecting means for detecting some temperature provided in the vehicle. Since it can be estimated, there is no need to consider an increase in cost. Therefore, when the battery mounted on the vehicle is controlled to be charged with an appropriate voltage, the required battery temperature is often obtained indirectly as described above (for example, Patent Document 1). reference.).
JP-A-7-227047

  However, in the method disclosed in Patent Document 1, it is an indispensable condition that the mounting position of the battery mounted on the vehicle is in the engine room.

  Specifically, in Patent Document 1, as a reference temperature for estimating the battery temperature, a value detected from an intake air temperature detecting means for detecting an intake air temperature of the engine and a temperature of cooling water for cooling the engine are used. The value detected from the cooling water temperature detection means to detect is used. Further, the vehicle speed of the vehicle is detected, and the estimated battery temperature is corrected by correcting the intake air temperature detected by the intake air temperature detecting means described above according to the detected vehicle speed.

  The mounting position of the battery mounted on the vehicle is not only in the engine room as described above, but may be in the trunk room at the rear of the vehicle when the engine room is a front engine. In particular, in a so-called hybrid car that uses both an engine and a battery as a power source for a vehicle, the position for mounting a relatively large-sized high-voltage battery used as a power source for the vehicle is limited. Installation is very necessary.

  As described above, when charging is performed on a battery that is not mounted in the engine room, the battery temperature cannot be measured using the method disclosed in Patent Document 1, and the battery is appropriate for the battery. There is a problem that it cannot be charged with voltage.

  Therefore, the present invention has been devised to solve the above-described problems, and accurately estimates the battery temperature with an inexpensive device configuration without depending on the mounting position of the battery mounted on the vehicle. An object of the present invention is to provide a battery temperature estimation device that can perform the above-described operation.

  A battery temperature estimation device of the present invention detects a vehicle battery mounted in a trunk room of a vehicle, first vehicle interior temperature detection means for detecting a vehicle interior temperature of the vehicle, and a vehicle interior solar radiation amount. The solar radiation amount detecting means, the vehicle interior temperature adjusting means for adjusting the vehicle interior temperature of the vehicle, and the solar radiation amount detected by the solar radiation amount detecting means less than a predetermined value. First battery temperature estimating means for setting the vehicle interior temperature detected by one vehicle interior temperature detecting means to the battery temperature of the vehicle battery, and the amount of solar radiation in the vehicle interior is equal to or greater than a predetermined value. Temperature difference estimating means for estimating a temperature difference between the vehicle interior temperature detected by the first vehicle interior temperature detecting means and the temperature in the trunk room in the trunk room, and the temperature The temperature difference estimated by the estimation means is added to the vehicle interior temperature detected by the first vehicle interior temperature detection means according to the operating state of the vehicle interior temperature adjustment means, or the vehicle interior temperature The above-mentioned problem is solved by providing second battery temperature estimating means for subtracting from the battery temperature of the vehicle battery.

  When the solar radiation amount detected by the solar radiation amount detecting means is equal to or greater than a predetermined value, the battery temperature estimating device of the present invention has a vehicle interior solar radiation amount detected from the solar radiation amount detecting means, and an operating state of the vehicle interior temperature adjusting means. In response, the temperature difference between the vehicle interior temperature detected by the first vehicle interior temperature detection means and the temperature in the trunk room in the trunk room in which the vehicle battery is mounted is estimated and added to the vehicle interior temperature, or Subtract from the passenger compartment temperature to obtain the battery temperature of the vehicle battery.

  Further, the battery temperature estimation device of the present invention uses the vehicle interior temperature detected by the first vehicle interior temperature detection means for the vehicle when the amount of solar radiation detected by the solar radiation amount detection means is smaller than a predetermined value. The battery temperature of the battery.

  As a result, even if a dedicated temperature detection device for detecting the battery temperature is not provided in the vehicle, it is possible to more accurately detect the detected value in the trunk room from the detection value detected by the existing detection means provided in advance for another use in the vehicle. The battery temperature of the vehicle battery mounted on can be estimated.

  Therefore, even if it is a vehicle battery mounted in the trunk room instead of the engine room, it is possible to estimate the battery temperature more accurately with an inexpensive apparatus configuration utilizing existing detection means.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  The configuration of the battery temperature estimation device 10 shown as an embodiment of the present invention will be described with reference to FIGS.

  As shown in FIG. 1, the battery temperature estimation device 10 includes a solar radiation sensor 1, an inker sensor 2, an outside air temperature sensor 3, an intake air temperature sensor 4, an air conditioner 15 (hereinafter referred to as an air conditioner 15), an ECU. (Electronic Control Unit: Electronic Control Unit) 5 and installed in the vehicle 20 as shown in FIG.

  As shown in FIG. 2, the vehicle 20 in which the battery temperature estimation device 10 is installed includes a battery 11 that supplies power to auxiliary equipment of the vehicle 20 in a trunk room 21, and a drive motor (not shown) that drives the vehicle 20. This is a so-called hybrid car equipped with a high voltage battery 12 for supplying electric power and using an engine (not shown) and a drive motor as power sources.

  The battery 11 and the high voltage battery 12 are charged by supplying power generated by an alternator (generator) (not shown) attached to an engine (not shown). The high voltage battery 12 is also supplied with electric power obtained by regenerative braking and is charged.

  The solar radiation sensor 1, the inker sensor 2, and the outside air temperature sensor 3 are sensors provided in advance for automatic operation control of the air conditioner 15 that is an air conditioner provided in the vehicle 20.

  As shown in FIG. 2, the solar radiation sensor 1 is provided on a dashboard 23 or the like in the passenger compartment 22 and detects the amount of solar radiation incident on the passenger compartment 22. The amount of solar radiation detected by the solar radiation sensor 1 is output to the ECU 5 to be used for automatically controlling the air conditioner 15 and is used for estimating the battery temperature of the battery 11 and the high voltage battery 12.

  The amount of solar radiation detected by the solar radiation sensor 1 is also used for control of an unillustrated auto light system provided in the vehicle 20.

  As shown in FIG. 2, the in-car sensor 2 detects a passenger compartment temperature (a passenger compartment front temperature) in front of the passenger compartment 22 provided on a dashboard 23 or the like in the passenger compartment 22. The passenger compartment front temperature detected by the in-car sensor 2 is output to the ECU 5 and used for controlling the automatic operation of the air conditioner 15, and also used for estimating the battery temperature of the battery 11 and the high-voltage battery 12.

  As shown in FIG. 2, the outside air temperature sensor 3 is provided in the bumper 24 of the vehicle 20 and detects the outside air temperature in the passenger compartment 22. The outside air temperature detected by the outside air temperature sensor 3 is output to the ECU 5 and used for controlling the air conditioner 15 to be automatically operated, and also used for estimating the battery temperatures of the battery 11 and the high voltage battery 12.

  The intake air temperature sensor 4 is provided in the cooling fan 13 that cools the high-voltage battery 12 mounted in the trunk room 21, and the temperature of the air in the rear of the vehicle compartment 22 that is taken in for cooling through the rear parcel 25 (vehicle interior). Detect backward temperature). The vehicle interior rear temperature detected by the intake air temperature sensor 4 is output to the ECU 5 and used to control the work amount of the cooling fan 13 and is used to estimate the battery temperatures of the battery 11 and the high voltage battery 12.

  As described above, the air conditioner 15 controls the temperature of the air conditioner 15 based on the amount of solar radiation detected by the solar radiation sensor 1, the inker sensor 2, and the outside air temperature sensor 3, the vehicle interior front temperature, and the outside air temperature. The air is discharged with a desired air volume, and the temperature in the passenger compartment 22 is automatically adjusted to the set temperature.

  The air conditioner 15 is in an activated state (on state) or a stopped state (off state) by the control of the ECU 5 according to whether the air conditioner switch 16 is on or off.

  The ECU 5 comprehensively controls various functions of the vehicle 20, and executes automatic operation control of the air conditioner 15 and processing for estimating the battery temperature of the battery 11 and the high voltage battery 12.

  Next, the battery temperature estimation processing operation by the battery temperature estimation device 10 will be described using the flowchart shown in FIG.

  In step S1, the ECU 5 determines whether the amount of solar radiation output from the solar radiation sensor 1 is equal to or greater than a specified value. The ECU 5 advances the process to step S2 when the amount of solar radiation is equal to or greater than the specified value, and advances the process to step S5 when it is smaller than the specified value.

  The prescribed value for determining the amount of solar radiation detected by the solar radiation sensor 1 is detected from the detection value detected from the inker sensor 2 and the outside air temperature sensor 3 when the solar radiation amount is increased. It is a value determined from a temperature rise measurement experiment that measures how the detected value changes.

  In step S <b> 2, the ECU 5 determines whether the air conditioner switch 16 is input and the air conditioner 15 is turned on.

  When the air conditioner switch 16 is input and the air conditioner 15 is on, the ECU 5 advances the process to step S3. In addition, when the air conditioner switch 16 is not input and the air conditioner 15 is in the off state, the ECU 5 advances the process to step S4.

  In step S3, the ECU 5 determines the vehicle interior front temperature Trf detected from the inker sensor 2 according to the amount of solar radiation detected from the solar radiation sensor 1 and whether the air conditioner 15 is on or off. The correction value ΔT is added to obtain the estimated battery temperature Tb of the battery 11 and the high voltage battery 12.

  In step S3, the ECU 5 first operates with the amount of solar radiation being large and the air conditioner 15 being in an on state, so that the vehicle interior temperature in the vehicle interior 22 (the vehicle interior front temperature or the vehicle interior rear temperature) Then, it is determined that the temperature difference with the trunk room temperature in the trunk room 21 is large.

  In this case, from the safety of charging the battery 11 and the high voltage battery 12, the outside air temperature and the vehicle interior temperature (the vehicle interior front temperature or the vehicle interior rear temperature) are simply compared, and the vehicle interior temperature ( The vehicle interior front temperature or the vehicle interior rear temperature) can be considered as the estimated battery temperature, but if the vehicle interior temperature (vehicle interior front temperature or vehicle interior rear temperature) is used as the battery estimated temperature under these conditions, The battery temperature may be considerably lower than the battery temperature.

  Therefore, a value obtained by adding the correction value ΔT shown in FIG. 4 determined by the amount of solar radiation and the on / off state of the air conditioner 15 to the vehicle interior front temperature Trf detected from the in-car sensor 2 is set as the estimated battery temperature Tb. .

  This correction value ΔT is a value indicating a temperature difference between the passenger compartment temperature in the passenger compartment 22 and the trunk compartment temperature in the trunk room 21, and the amount of solar radiation detected by the solar radiation sensor 1 shown in FIG. It can be estimated from the relationship determined according to the 15 driving states.

  As shown in FIG. 4, the correction value ΔT has an ascending gradient according to the amount of solar radiation detected by the solar radiation sensor 1 when the air conditioner 15 is in the on state or the off state. In the on state, the correction value ΔT has a change rate that does not increase so much even if the amount of solar radiation is large.

  This is because the temperature increase in the passenger compartment 22 is larger than the temperature increase in the trunk room 21 in which the battery 11 and the high-voltage battery 12 are mounted. This is because the rise in temperature is suppressed.

  As a result, the trunk room temperature can be accurately estimated by adding the correction value ΔT to the vehicle interior front temperature Trf. Therefore, the accurate battery temperature of the battery 11 and the high voltage battery 12 mounted in the trunk room 21 can be estimated. Can be estimated.

  As shown in FIG. 4, the correction value ΔT when the air conditioner 15 is turned on varies in gradient according to the amount of adjustment of the passenger compartment temperature in the passenger compartment 22 by the air conditioner 15, that is, the effectiveness of the air conditioner 15. It will be. When the power consumption of the air conditioner 15 is increased and the passenger compartment temperature in the passenger compartment 22 is lowered, the rate of change of the correction value ΔT decreases.

  In step S4, the ECU 5 is determined based on the amount of solar radiation detected from the solar radiation sensor 1 and whether the air conditioner 15 is in an on state or an off state from the vehicle interior front temperature Trf detected from the inker sensor 2. The correction value ΔT is subtracted to obtain the estimated battery temperature Tb of the battery 11 and the high voltage battery 12.

  In this step S4, first, the ECU 5 has a large amount of solar radiation and the air conditioner 15 is in an off state and is not operating, so that the vehicle interior temperature in the vehicle interior 22 (the vehicle interior front temperature or the vehicle interior rear temperature) The trunk room temperature in the trunk room 21 is determined to be higher than the outside air temperature.

  In this case, from the safety required for charging the battery 11 and the high voltage battery 12, the outside air temperature is simply compared with the vehicle interior temperature (the vehicle interior front temperature or the vehicle interior rear temperature), and the low temperature outside air temperature is determined by the battery. Although it is conceivable that the estimated temperature is set, if the outside air temperature is set as the estimated battery temperature under such conditions, there is a possibility that the estimated temperature is considerably lower than the actual battery temperature.

  Therefore, a value obtained by subtracting the correction value ΔT shown in FIG. 4 determined by the amount of solar radiation and the on / off state of the air conditioner 15 from the cabin front temperature Trf detected by the inker sensor 2 without using the outside air temperature. Assume that the estimated battery temperature Tb.

  As described above, the correction value ΔT shown in FIG. 4 has an upward gradient according to the amount of solar radiation detected by the solar radiation sensor 1 in both cases where the air conditioner 15 is in the on state and the off state. When the air conditioner 15 is in the off state, the correction value ΔT also has a change rate that greatly increases in accordance with the amount of solar radiation.

  This is because the temperature rise in the passenger compartment 22 is larger than the temperature rise in the trunk room 21 in which the battery 11 and the high voltage battery 12 are mounted, and the air conditioner 15 is turned off. This is because the rise in the price is promoted.

  Accordingly, the temperature in the trunk room can be accurately estimated by subtracting the correction value ΔT from the vehicle interior front temperature Trf. Therefore, the accurate battery temperature of the battery 11 and the high voltage battery 12 mounted in the trunk room 21 can be estimated. Can be estimated.

  In step S5, the ECU 5 compares the vehicle interior front temperature Trf detected by the in-car sensor 2, the outdoor air temperature To detected by the external air temperature sensor 3, and the vehicle interior rear temperature Trr detected by the intake air temperature sensor 4. The lowest temperature is set as the estimated battery temperature Tb of the battery 11 and the high voltage battery 12.

  In step S5, it is not always necessary to use the outside air temperature To detected from the outside air temperature sensor 3. When the outside air temperature sensor 3 is not provided in the vehicle 20, the vehicle interior detected from the inker sensor 2 is used. The front temperature Trf and the vehicle interior rear temperature Trr detected from the intake air temperature sensor 4 may be compared, and the lower temperature may be set as the estimated battery temperature Tb of the battery 11 and the high voltage battery 12.

  In this way, when the amount of solar radiation detected by the solar radiation sensor 1 is equal to or greater than a predetermined specified value, the battery temperature estimation device 10 determines the amount of solar radiation in the passenger compartment 22 detected from the solar radiation sensor 1 and the air conditioner 15. Depending on the operating state, the vehicle interior front temperature Trf detected by the in-car sensor 2 is corrected with the correction value ΔT, so that a separate dedicated temperature detection device for detecting the battery temperature is not provided. The estimated battery temperature Tb can be estimated more accurately from the detection value detected by an existing sensor provided in advance for the application.

  Further, the correction value ΔT, which is a value indicating the temperature difference between the passenger compartment temperature in the passenger compartment 22 and the trunk compartment temperature in the trunk room 21, is increased in accordance with the increase in the amount of solar radiation detected by the solar radiation sensor 1. Since the difference in temperature rise in the passenger compartment 22 and the trunk room 21 can be absorbed by reducing the air conditioner 15 as the adjustment amount increases, the estimated battery temperature Tb can be estimated more accurately. it can.

  Further, when the amount of solar radiation detected by the solar radiation sensor 1 is smaller than a predetermined specified value, the battery temperature estimation device 10 detects the vehicle interior forward temperature Trf detected from the inker sensor 2 and the intake air temperature sensor. If a vehicle interior rear temperature Trr and an outside air temperature sensor are provided, the detected value of the lowest temperature is selected from any of the outside air temperatures To detected by the outside air temperature sensor 3, and the estimated battery temperature Tb By doing so, the battery temperature of the battery 11 and the high voltage battery 12 mounted in the trunk room 21 can be estimated erroneously high, and battery deterioration caused by charging at a high voltage can be avoided.

  Although the vehicle 20 shown as the embodiment of the present invention is a so-called hybrid car, the present invention is not limited to this, and without mounting the high voltage battery 12 that is a power source for driving the vehicle, The present invention can also be applied to a normal vehicle in which only the battery 11 is mounted in the trunk room 21, and the battery temperature can be accurately estimated by using a similar method.

  The above-described embodiment is an example of the present invention. For this reason, the present invention is not limited to the above-described embodiment, and various modifications can be made depending on the design and the like as long as the technical idea according to the present invention is not deviated from this embodiment. Of course, it is possible to change.

It is a figure for demonstrating the structure of the battery temperature estimation apparatus shown as embodiment of this invention. It is the figure which showed typically the arrangement position of each function part previously provided in the vehicle used with the said battery temperature estimation apparatus. It is a flowchart for demonstrating the battery temperature estimation process operation | movement by the said battery temperature estimation apparatus. It is the figure which showed the mode of correction value (DELTA) T which changes according to the amount of solar radiation, and the operating condition of an air-conditioner.

Explanation of symbols

1 Solar radiation sensor 2 Inker sensor 3 Outside air temperature sensor 5 ECU (Electronic Control Unit)
11 Battery 12 High voltage battery 15 Air conditioner 21 Trunk room 22 Car compartment

Claims (8)

A vehicle battery mounted in a vehicle trunk room;
First vehicle interior temperature detection means for detecting the vehicle interior temperature of the vehicle;
Solar radiation amount detecting means for detecting the amount of solar radiation in the vehicle interior of the vehicle,
Vehicle interior temperature adjusting means for adjusting the vehicle interior temperature of the vehicle;
When the solar radiation amount detected by the solar radiation amount detection means is smaller than a predetermined value, the vehicle interior temperature detected by the first vehicle interior temperature detection means is set as the battery temperature of the vehicle battery. First battery temperature estimating means for
When the amount of solar radiation in the passenger compartment is equal to or greater than a predetermined value, a temperature difference between the passenger compartment temperature detected by the first passenger compartment temperature detecting means and the trunk compartment temperature in the trunk room is estimated. Temperature difference estimation means;
The temperature difference estimated by the temperature difference estimating means is added to the vehicle interior temperature detected by the first vehicle interior temperature detecting means according to the operating state of the vehicle interior temperature adjusting means, or A battery temperature estimation device, comprising: a second battery temperature estimation unit that subtracts the vehicle temperature from the vehicle interior temperature to obtain the battery temperature of the vehicle battery. The temperature difference estimating means calculates the temperature difference between the passenger compartment temperature detected by the first passenger compartment temperature detecting means and the trunk room temperature from the solar radiation amount detected by the solar radiation amount detecting means. The battery temperature estimation device according to claim 1, wherein the estimation is performed. The battery temperature estimation device according to claim 2, wherein the temperature difference estimated by the temperature difference estimation means increases with an increase in the amount of solar radiation detected by the solar radiation amount detection means. The temperature difference estimating means estimates the temperature difference between the passenger compartment temperature detected by the first passenger compartment temperature detecting means and the trunk room temperature from the operating state of the passenger compartment temperature adjusting means. The battery temperature estimation device according to claim 2 or claim 3, wherein The battery temperature estimation device according to claim 4, wherein the temperature difference estimated by the temperature difference estimation unit decreases with an increase in an adjustment amount of the vehicle interior temperature by the vehicle interior temperature adjustment unit. The second battery temperature estimating means includes:
When the vehicle interior temperature is adjusted by the vehicle interior temperature adjusting means, the temperature estimated by the temperature difference estimating means is added to the vehicle interior temperature detected by the first vehicle interior temperature detecting means. Add the difference,
The temperature estimated by the temperature difference estimating means from the vehicle interior temperature detected by the first vehicle interior temperature detecting means when the vehicle interior temperature is not adjusted by the vehicle interior temperature adjusting means. The battery temperature estimation device according to claim 1, wherein the difference is subtracted. As the vehicle battery, a first vehicle battery used as a power source for driving the vehicle and a second vehicle battery used as a power source for driving an auxiliary device of the vehicle are provided in the trunk room. When the vehicle interior temperature detection means is attached to the front of the vehicle interior and the temperature in the front of the vehicle interior is detected,
A second vehicle interior that detects the temperature of the air behind the vehicle interior that is taken in by the intake air cooling means that takes in the air from the vehicle interior rear and cools the first vehicle battery, as the vehicle interior rear temperature. Temperature detection means,
The first battery temperature estimation means includes the vehicle interior front temperature detected by the first vehicle interior temperature detection means and the vehicle interior rear temperature detected by the second vehicle interior temperature detection means. The battery temperature estimation device according to claim 1, wherein the lower vehicle interior temperature is set as the battery temperature of the vehicle battery. An outside air temperature detecting means for detecting outside air temperature outside the vehicle,
The first battery temperature estimation means includes the vehicle interior front temperature detected by the first vehicle interior temperature detection means, the vehicle interior rear temperature detected by the second vehicle interior temperature detection means, The battery temperature estimation device according to claim 7, wherein the outside temperature detected by the outside temperature detecting means is compared with the lowest temperature as the battery temperature of the vehicle battery.

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