JP2018032535A - Cell temperature calculation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cell temperature calculation device capable of acquiring an accurate surface temperature of a cell.SOLUTION: A cell temperature calculation device creates a correction value map 72 by associating a surface temperature variation, which is a difference between a surface temperature with no error detected by a surface temperature sensor 34 attached to a surface of a cell 10 in a state in which an influence of cooling air from an air supply fan 12 is not received and a surface temperature with an error detected by the surface temperature sensor 34 in a state in which the air supply fan 12 is driven at a predetermined rotation frequency and an influence of cooling air is received, with the predetermined rotation frequency and an air surface temperature difference, which is a difference between an air temperature TC of air sent and supplied to the cell 10 and the surface temperature with no error. At a time point of calculating a surface temperature of the cell 10, the cell temperature calculation device, on the basis of an air surface temperature difference at the time point and a rotation frequency of the air supply fan, reads out a corresponding surface temperature variation from the correction value map 72; and adds the read surface temperature variation to a surface temperature with an error at the time point to calculate a surface temperature of the cell.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a battery temperature calculation device used in a cooling device for cooling an in-vehicle battery.

  In recent years, electric vehicles such as an electric vehicle using a motor as a drive source and a hybrid vehicle using a motor and an engine as a drive source are often used. These electric vehicles are equipped with a chargeable / dischargeable battery for supplying electric power to the motor and charging the generated electric power when the motor is operated as a generator, and a cooling device for cooling the battery. The cooling device sucks the cooling air by the suction action of the blower fan, and cools the battery by flowing the sucked cooling air through the cooling flow path around the battery.

  The cooling device is provided with a temperature sensor for detecting the temperature of the battery, and the cooling device rotates the blower fan when the battery temperature detected by the temperature sensor becomes equal to or higher than a predetermined temperature. Drive to cool the battery.

  Patent Document 1 discloses that in a cooling device that cools a battery mounted on an electric vehicle, a temperature sensor is attached to a heat sink of the battery, and the temperature of the battery is estimated based on the temperature detected by the temperature sensor. .

JP 2004-022496 A

  By the way, when a thermistor (surface temperature sensor) is attached to the surface of the battery and the surface temperature of the battery is detected by the thermistor, the thermistor is blown by cooling air, so that the temperature lower than the actual surface temperature of the battery is reduced. It may be detected (an error occurs in the detected temperature).

  In this case, the detected temperature of the battery may be inaccurate, and the battery may not be properly cooled.

  In addition, since the magnitude of the detected temperature error varies depending on the element error of the thermistor, how the cooling air hits, the rotational speed of the blower fan, etc., the detected value of the thermistor is corrected using a preset correction value. However, it is difficult to obtain an accurate battery surface temperature.

  Accordingly, an object of the present invention is to provide a battery temperature calculation device that can acquire an accurate surface temperature of a battery.

  The battery temperature calculation device of the present invention is a battery temperature calculation device for calculating the surface temperature of a battery, and is attached to the surface of the battery and is affected by cooling air supplied from a blower fan. A surface temperature sensor for detecting the air temperature, an air temperature sensor for detecting an air temperature of air supplied from the blower fan to the battery, and the surface temperature sensor in a state not affected by cooling air from the blower fan. The difference between the surface temperature without error, which is the surface temperature of the battery detected, and the surface temperature with error detected by the surface temperature sensor in a state where the blower fan is driven at a predetermined rotational speed and is affected by cooling air. A storage for storing the surface temperature change amount corresponding to the predetermined rotational speed and an air surface temperature difference that is a difference between the air temperature and the error-free surface temperature. And calculating the air surface temperature difference from the error-free surface temperature acquired at the start of driving of the blower fan and the air temperature acquired at the time, at the time of performing the calculation, and the calculated Based on the air surface temperature difference and the rotational speed of the blower fan at the time point, the corresponding surface temperature change amount is read from the storage unit, and the read surface temperature change amount is determined as the error at the time point. And a calculating unit that calculates the surface temperature of the battery by adding to the surface temperature.

  According to the present invention, accurate correction according to the rotational speed of the blower fan and the air surface temperature difference is performed, so that the accurate surface temperature of the battery can be acquired.

It is a figure which shows an example of a structure of the battery temperature calculation apparatus and cooling device in embodiment of this invention. It is a flowchart which shows an example of the flow of the preparation process of the correction value map which the battery temperature calculation apparatus in embodiment of this invention performs. It is a wave form diagram for demonstrating the preparation process of the correction value map which the battery temperature calculation apparatus in embodiment of this invention performs. It is a table | surface which shows an example of the correction value map in embodiment of this invention. It is a flowchart which shows an example of the flow of the correction process using the correction value map which the battery temperature calculation apparatus in embodiment of this invention performs. It is a wave form diagram for demonstrating the correction process using the correction value map which the battery temperature calculation apparatus in embodiment of this invention performs.

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

  FIG. 1 shows an example of the configuration of the battery temperature calculation device 70 of the present embodiment. FIG. 1 also shows the battery 10, the inverter 28, and the motor generator 30 in addition to the cooling device 50 that controls the cooling of the battery 10 using the surface temperature TB1 of the battery 10 calculated by the battery temperature calculation device 70. Shown together.

  The battery 10, the cooling device 50, and the battery temperature calculation device 70 of the present embodiment are mounted on an electric vehicle such as a hybrid vehicle or an electric vehicle.

  The battery 10 is a secondary battery such as a chargeable / dischargeable lithium ion battery. The battery 10 is connected to an inverter 28 via a positive electrode line 24 and a negative electrode line 26. Inverter 28 converts the DC power of battery 10 into AC power to drive motor generator 30 for driving the vehicle. Further, the AC power generated by the motor generator 30 is converted into DC power by the inverter 28 and the battery 10 is charged.

  The cooling device 50 includes an intake duct 20, a blower fan 12, an exhaust duct 22, and a cooling control unit 40. One end of the intake duct 20 is connected to an intake port 18 provided in the vehicle interior, and the other end of the intake duct 20 is connected to an inlet of a battery housing case 23 that houses the battery 10. A blower fan 12 is attached inside the intake duct 20. Further, the battery 10 includes a cooling channel (not shown) inside. An exhaust duct 22 for discharging the air after cooling the battery 10 is attached to the outlet of the battery housing case 23.

  The thick black arrows in FIG. 1 indicate the flow of cooling air. The cooling device 50 drives the blower fan 12 to take cooling air from the passenger compartment into the intake duct 20 via the intake port 18. The taken cooling air flows into the battery housing case 23 through the intake duct 20 and is guided to the cooling flow path inside the battery 10 to cool the battery 10. The cooling air after cooling the battery 10 passes through the outlet of the battery housing case 23 and is discharged from the exhaust duct 22.

  The cooling control unit 40 of the cooling device 50 controls the motor 16 that drives the blower fan 12 to adjust the rotational speed of the blower fan 12. Electric power is supplied to the motor 16 from the auxiliary battery. An air temperature sensor 32 that detects the air temperature of the cooling air supplied from the blower fan 12 to the battery 10 is attached inside the intake duct 20. The detected temperature TC of the air temperature sensor 32 is input to the cooling control unit 40. Further, the surface temperature TB1 of the battery 10 is input to the cooling control unit 40 from a temperature calculation control unit 60 of the battery temperature calculation device 70 described later. Normally, when the surface temperature TB1 of the battery 10 is higher than the detection temperature TC of the air temperature sensor 32 (TB1> TC), the cooling control unit 40 drives the blower fan 12 at the number of rotations corresponding to the surface temperature TB1 of the battery 10. . In addition, when the surface temperature TB1 of the battery 10 is low, the cooling control unit 40 stops the blower fan 12 because it is not necessary to cool the battery 10.

  Here, the battery temperature calculation device 70 of the present embodiment corrects the detected temperature TB of the surface temperature sensor 34 to calculate an accurate surface temperature TB1 of the battery 10, which is used as the cooling control unit 40 of the cooling device 50. By providing this, the cooling control unit 40 can accurately perform the cooling control.

  As shown in FIG. 1, the battery temperature calculation device 70 is attached to the surface of the battery 10 and the air temperature sensor 32 that detects the air temperature of the air supplied from the blower fan 12 to the battery 10. A surface temperature sensor 34 for detecting temperature and a temperature calculation control unit 60 are provided. The temperature calculation control unit 60 includes a microprocessor, and executes a program to generate a correction value map 72 described later and a correction process using the correction value map 72. The temperature calculation control unit 60 includes a storage unit 52 and a calculation unit 54. The storage unit 52 stores a correction value map 72 described later.

  The amount of error of the detected temperature TB of the surface temperature sensor 34 includes the amount of cooling air (the rotation speed of the blower fan 12), the air temperature of the cooling air applied to the battery 10 (the detected temperature TC of the air temperature sensor 32), and the actual amount. It depends on a difference from the surface temperature of the battery 10 (hereinafter referred to as an air surface temperature difference ΔT2). Further, the amount of error of the detected temperature TB of the surface temperature sensor 34 varies from individual to individual depending on the error of the element of the surface temperature sensor 34, the mounting error, how the cooling air hits, and the like.

  In view of this, the battery temperature calculation device 70 according to the present embodiment uses the surface temperature sensor 34 to be corrected to determine the amount of detected temperature error according to the rotational speed N of the blower fan 12 and the air surface temperature difference ΔT2. First, examine (learn) what happens. This is investigated by changing the rotational speed N of the blower fan 12 and the air surface temperature difference ΔT2. Thereby, a map (hereinafter referred to as a correction value map 72) of the detected temperature error amount associated with the rotational speed N of the blower fan 12 and the air surface temperature difference ΔT2 is created. Then, the correction value map 72 is stored in the storage unit 52.

  In order to obtain the above air surface temperature difference ΔT2, it is necessary to obtain the actual surface temperature of the battery 10 (the surface temperature TB1 without error). Further, in order to acquire the error amount of the detected temperature, it is necessary to obtain the surface temperature TB1 without error and the surface temperature TB2 with error. Therefore, in the present embodiment, the detected temperature TB detected by the surface temperature sensor 34 at the time of rising of the blower fan 12 (drive start point) that is not affected by the cooling air from the blower fan 12 is the surface without error. Acquired as temperature TB1. Further, the detected temperature TB detected by the surface temperature sensor 34 in a state in which the blower fan 12 is driven at a predetermined rotational speed N and is affected by the cooling air is acquired as the surface temperature TB2 having an error.

  The battery temperature calculation device 70 of the present embodiment is a surface with no error acquired when the blower fan 12 starts up at the time of correcting the detected temperature TB of the surface temperature sensor 34 (at the time of calculating the surface temperature TB1 of the battery 10). An air surface temperature difference ΔT2 is calculated from the temperature TB1 and the air temperature acquired at that time (the detected temperature TC of the air temperature sensor 32). Then, an error amount of the detected temperature corresponding to the air surface temperature difference ΔT2 and the rotational speed N of the blower fan 12 at that time is read from the correction value map 72 in the storage unit 52. Then, the detected temperature of the surface temperature sensor 34 is added by adding the error amount of the detected temperature to the detected temperature of the surface temperature sensor 34 affected by the cooling air detected at that time (surface temperature TB2 with error). TB is corrected and an accurate surface temperature TB1 of the battery 10 is calculated.

  Next, the creation of the correction value map 72 and the correction using the correction value map 72, which have been briefly described above, will be described in detail with reference to flowcharts.

FIG. 2 is a flowchart illustrating an example of a flow of a correction value map 72 creation process performed by the temperature calculation control unit 60 of the battery temperature calculation device 70 of the present embodiment. The temperature calculation control unit 60 executes the flow (creation process) in FIG. 2 at a predetermined cycle _TP1 .

  First, in S100 of FIG. 2, the temperature calculation control unit 60 acquires the detected temperature TB of the surface temperature sensor 34 as the surface temperature TB1 without error. At this time, the blower fan 12 is not yet driven to rotate, and the surface temperature sensor 34 is not affected by the cooling air.

  Next, in S102, the temperature calculation control unit 60 confirms whether or not the blower fan 12 is in a rotationally rising state, that is, whether or not the rotational driving is determined and rotational driving is started. In addition, this is good to acquire the signal which controls the drive of the ventilation fan 12, for example from the cooling control part 40 of the cooling device 50, and to recognize a drive start. In S102, when the blower fan 12 is not in the rotationally rising state (S102: No), the process of this cycle is ended.

  On the other hand, if the blower fan 12 is in a rotationally rising state (S102: Yes), the process proceeds to S104. In S104, the temperature calculation control unit 60 determines whether the rotation speed of the blower fan 12 has been stabilized, that is, the rotation speed of the blower fan 12 has reached the rotation number N according to the command of the cooling control unit 40 of the cooling device 50. It is confirmed whether or not the fan 12 is stably rotating at the rotation speed N. This information can be obtained, for example, by acquiring a command value of the rotational speed N from the cooling control unit 40 of the cooling device 50 and acquiring the rotation state of the blower fan 12 by a sensor attached to the blower fan 12. it can. Further, when a predetermined time has elapsed since the blower fan 12 has started to rotate, it may be determined that the rotational speed of the blower fan 12 has been stabilized.

  In the flow of FIG. 2, the error-free surface temperature TB1 is acquired at a time point (before S102) before the blower fan 12 enters the rotational rising state, but after the blower fan 12 enters the rotational rise state. You may acquire at the time of (after S102: Yes). That is, the detected temperature TB immediately before the influence of the cooling air, such as immediately before the start of the rotation of the blower fan 12, may be adopted as the surface temperature TB1 without error.

  If the rotational speed of the blower fan 12 is not stable in S104 (S104: No), the process waits until it is stabilized. If the rotation speed of the blower fan 12 is stable in S104 (S104: Yes), the process proceeds to S106. In S106, the temperature calculation control unit 60 acquires the rotational speed N of the blower fan 12. This is acquired, for example, by receiving the rotational speed N (command value) of the blower fan 12 from the cooling control unit 40 of the cooling device 50.

  Next, in S <b> 108, the temperature calculation control unit 60 acquires the detected temperature TC of the air temperature sensor 32. In S110, the temperature calculation control unit 60 acquires the detected temperature TB of the surface temperature sensor 34 as the surface temperature TB2 having an error. At this time, the surface temperature sensor 34 is affected by the cooling air.

  Next, in S112, the temperature calculation control unit 60 subtracts TB1 from TB2 to obtain the surface temperature change amount ΔT1. This surface temperature change amount ΔT1 is an error amount of the detected temperature TB of the surface temperature sensor 34 described above.

  In step S114, the temperature calculation control unit 60 subtracts TB1 from TC to obtain the air surface temperature difference ΔT2. In S116, the temperature calculation control unit 60 associates the surface temperature change amount ΔT1 (detected temperature error amount) with the correction value map 72 in association with the rotational speed N of the blower fan 12 and the air surface temperature difference ΔT2. Record. The correction value map 72 is stored in the storage unit 52.

  The temperature calculation control unit 60 performs the process of creating the correction value map 72 described above by changing the rotational speed N of the blower fan 12 and the air surface temperature difference ΔT2 in various ways, and the surface temperature change amount in each combination thereof. A correction value map 72 is created by acquiring ΔT1 (detected temperature error amount).

  FIG. 3 shows changes in the rotational speed of the blower fan 12, changes in the detected temperature TC of the air temperature sensor 32, and changes in the detected temperature TB of the surface temperature sensor 34 during the process of creating the correction value map 72. It is a wave form diagram which shows an example. As illustrated in FIG. 3, the temperature calculation control unit 60 acquires the error-free surface temperature TB1 at the time when the blower fan 12 is in a rotationally rising state. In the flow of FIG. 2, the error-free surface temperature TB1 is acquired even before the start of the rotation of the blower fan 12, but this is not used (shown as TB1 (provisional) in FIG. 3). And after the ventilation fan 12 will be in a rotation start-up state, it waits until the rotation speed of the ventilation fan 12 is stabilized. Then, when the rotational speed of the blower fan 12 is stabilized, the rotational speed N of the blower fan 12, the air temperature TC, and the surface temperature TB2 with error are acquired, and the surface temperature change amount that is the difference between TB2 and TB1. ΔT1 is calculated, and an air surface temperature difference ΔT2 that is a difference between TC and TB1 is calculated. Then, the surface temperature change amount ΔT1 is recorded in the correction value map 72 in association with the rotational speed N of the blower fan 12 and the air surface temperature difference ΔT2.

  FIG. 4 is a table showing an example of the correction value map 72. As shown in FIG. 4, the correction value map 72 is a combination of each value of the air surface temperature difference ΔT2_i (i = 1 to k) and each value of the rotational speed Nj (j = 1 to m) of the blower fan 12. On the other hand, the surface temperature change amount ΔT1_ij (i = 1 to k, j = 1 to m) is defined. The temperature calculation control unit 60 creates the correction value map 72 by repeating the process of creating the correction value map 72, but the surface temperature change amount ΔT1 (error amount of the detected temperature) is considered to change over time. Even after the correction value map 72 is once created, it is desirable to repeat the process of creating the correction value map 72 and update the correction value map 72 as needed.

Next, correction using the correction value map 72 will be described. FIG. 5 is a flowchart illustrating an example of the flow of correction processing using the correction value map 72 performed by the temperature calculation control unit 60 of the battery temperature calculation device 70 of the present embodiment. The temperature calculation control unit 60 executes the flow (correction process) in FIG. 5 at a predetermined period _TP2 .

  First, in S200 of FIG. 5, the temperature calculation control unit 60 confirms whether the blower fan 12 is in a rotating state. When it is not in the rotating state (S200: No), the process proceeds to S202. In S202, the temperature calculation control unit 60 confirms whether or not the blower fan 12 is in a rotationally rising state, that is, whether or not the rotational driving is determined and rotational driving is started. Note that, as in the creation process described above, for example, a signal for controlling the driving of the blower fan 12 may be acquired from the cooling control unit 40 of the cooling device 50 to recognize the start of driving.

  In S202, when the blower fan 12 is not in the rotationally rising state (S202: No), the process proceeds to S203. In S203, the temperature calculation control unit 60 acquires the detected temperature TB of the surface temperature sensor 34 as the error-free surface temperature TB1. At this time, the blower fan 12 is not rotating, the surface temperature sensor 34 is not affected by the cooling air, and there is no error in the detected temperature TB. Therefore, at this time (the state where the blower fan 12 is not rotating), the detected temperature TB of the surface temperature sensor 34 is handled as the surface temperature TB1 without error. After S203, the process in this cycle is terminated.

  On the other hand, when the blower fan 12 is in a rotationally rising state (S202: Yes), the process proceeds to S204. In S204, the temperature calculation control unit 60 sets the variable n to 0. In S206, the temperature calculation control unit 60 acquires the detected temperature TB of the surface temperature sensor 34 as the error-free surface temperature TB1 (0). At this time, the surface temperature sensor 34 is not yet affected by the cooling air.

  In the flow of FIG. 5, the error-free surface temperature TB1 (0) is acquired at a time point after the blower fan 12 enters the rotation rising state (after S202: Yes), but the blower fan 12 rotates. You may acquire at the time (before S202) before becoming a rising state. That is, the detected temperature TB immediately before the influence of the cooling air, such as immediately before the start of the rotation of the blower fan 12, may be adopted as the surface temperature TB1 (0) without error.

  After S206, the process proceeds to S208. In S208, the temperature calculation control unit 60 determines whether the rotation speed of the blower fan 12 is stable, that is, the rotation speed of the blower fan 12 reaches the rotation number N according to the command of the cooling control unit 40 of the cooling device 50. It is confirmed whether or not the fan 12 is stably rotating at the rotation speed N. Note that this information is obtained by, for example, a sensor that acquires the command value of the rotation speed N from the cooling control unit 40 of the cooling device 50 and sets the rotation state of the blower fan 12 to the blower fan 12 in the same manner as the creation process described above. It can be obtained by acquiring. Further, when a predetermined time has elapsed since the blower fan 12 has started to rotate, it may be determined that the rotational speed of the blower fan 12 has been stabilized.

  If the rotational speed of the blower fan 12 is not stable in S208 (S208: No), the process waits until it becomes stable. If the rotational speed of the blower fan 12 is stable in S208 (S208: Yes), the process proceeds to S210. In S210, the temperature calculation control unit 60 adds 1 to the variable n and updates the value of the variable n. Here, the variable n = 1.

  Next, in S212, the temperature calculation control unit 60 acquires the rotational speed N (n) of the blower fan 12. Here, since the variable n = 1, N (1) is acquired. This is acquired by receiving, for example, the rotational speed N (command value) of the blower fan 12 from the cooling control unit 40 of the cooling device 50 as in the above-described creation process.

  Next, in S214, the temperature calculation control unit 60 acquires the detected temperature TC (n) (here, TC (1)) of the air temperature sensor 32. In S216, the temperature calculation control unit 60 acquires the detected temperature TB of the surface temperature sensor 34 as the surface temperature TB2 (n) with error (here, TB2 (1)). At this time, the surface temperature sensor 34 is affected by the cooling air.

  Next, in S218, the calculation unit 54 of the temperature calculation control unit 60 subtracts TB1 (n-1) from TC (n) to obtain the air surface temperature difference ΔT2 (n). Here, since the variable n = 1, TB1 (0) is subtracted from TC (1) to obtain the air surface temperature difference ΔT2 (1).

  In S220, the calculation unit 54 of the temperature calculation control unit 60 stores the rotational speed N (n) of the blower fan 12 and the surface temperature change amount ΔT1 (n) corresponding to the air surface temperature difference ΔT2 (n). Read out from the correction value map 72 in the unit 52. Here, since the variable n = 1, the rotational speed N (1) of the blower fan 12 and the surface temperature change amount ΔT1 (1) corresponding to the air surface temperature difference ΔT2 (1) are stored in the correction value map in the storage unit 52. 72.

  Then, in S222, the calculation unit 54 of the temperature calculation control unit 60 adds the surface temperature change amount ΔT1 (n) (detected temperature error amount) to the surface temperature TB2 (n) with error to obtain the surface temperature TB1 without error. (N) is acquired. Here, since the variable n = 1, the surface temperature TB1 (1) without error is obtained by adding the surface temperature variation ΔT1 (1) to the surface temperature TB2 (1) with error.

  As described above, the error-free surface temperature TB1 (0) in the case of the variable n = 0 is the detected temperature TB of the surface temperature sensor 34 in a state where it is not affected by the cooling air from the blower fan 12. Then, the error-free surface temperature TB1 (1) in the case of the next variable n = 1 is the error-free surface temperature TB1 obtained by correction (by calculation) first.

  In the correction process of the next cycle (flow of FIG. 5), since the blower fan 12 is in a rotating state, “Yes” (S200: Yes) is obtained in the confirmation of “whether the blower fan 12 is in a rotating state” in S200, and the process proceeds to S210. move on. In S210, the temperature calculation control unit 60 adds 1 to the variable n (current variable n = 1) and updates the value of the variable n, so that the variable n = 2. In S212 to S216, the temperature calculation control unit 60 sequentially obtains N (2), TC (2), and TB2 (2). Next, in S218, the calculation unit 54 of the temperature calculation control unit 60 subtracts the error-free surface temperature TB1 (1) calculated in the previous cycle from TC (2) to obtain the air surface temperature difference ΔT2 (2). get. In S220, the calculation unit 54 of the temperature calculation control unit 60 reads N (2) and ΔT1 (2) corresponding to ΔT2 (2) from the correction value map 72 in the storage unit 52. In S222, the calculation unit 54 of the temperature calculation control unit 60 adds the surface temperature change amount ΔT1 (2) to the surface temperature TB2 (2) with error to obtain the surface temperature TB1 (2) without error.

  The error-free surface temperature TB1 (2) in the case of the variable n = 2 described above is the error-free surface temperature TB1 obtained by the second correction (by calculation). As described above, the error-free surface temperature TB1 (2) is obtained by calculating the air surface temperature difference ΔT2 (2) using the error-free surface temperature TB1 (1) calculated in the previous cycle (S218). Has been obtained.

  Thus, by using the error-free surface temperature TB1 (n−1) obtained in the previous cycle (n−1), it is possible to calculate the current n error-free surface temperature TB1 (n). ing. Therefore, not only immediately after the start of rotation of the blower fan 12, but also in the rotation state of the blower fan 12 after the variable n = 2 (S200: Yes), the surface temperature TB1 (n ) Can be calculated.

  The temperature calculation control unit 60 similarly performs the correction process using the correction value map 72 described above even after the variable n = 3.

  FIG. 6 shows changes in the rotational speed of the blower fan 12, changes in the detected temperature TC of the air temperature sensor 32, and changes in the detected temperature TB of the surface temperature sensor 34 during the correction process using the correction value map 72. It is a wave form diagram which shows an example. As illustrated in FIG. 6, the temperature calculation control unit 60 acquires the detected temperature TB of the surface temperature sensor 34 as the error-free surface temperature TB1 at a time point before the rotation start of the blower fan 12. Next, when the blower fan 12 is in a rotationally rising state, the error-free surface temperature TB1 (0) is acquired, and the process waits until the rotational speed of the blower fan 12 is stabilized. Then, when the rotational speed of the blower fan 12 is stabilized, the rotational speed N (1) of the blower fan 12, the air temperature TC (1), and the surface temperature TB2 (1) with an error are acquired, and TC (1 ) And TB1 (0), an air surface temperature difference ΔT2 (1) is calculated (in FIG. 6, ΔT2 (n) is omitted). Then, the surface temperature change amount ΔT1 (1) corresponding to the rotational speed N (1) of the blower fan 12 and the air surface temperature difference ΔT2 (1) is read from the correction value map 72 in the storage unit 52. Then, the surface temperature change amount ΔT1 (1) is added to the surface temperature TB2 (1) with error to calculate the surface temperature TB1 (1) without error.

  As shown in FIG. 6, after the next cycle (n = 2) after the error-free surface temperature TB1 (1) is calculated, each time the correction process (the flow in FIG. 5) is executed, the error-free surface is obtained. Temperature TB1 (2), error-free surface temperature TB1 (3),. . . Thus, the error-free surface temperature TB1 (n) is calculated sequentially.

  The battery temperature calculation device 70 of the present embodiment described above is the correction target surface temperature sensor 34, and the rotation speed N of the blower fan 12, the air temperature TC of the cooling air applied to the battery 10, and the surface temperature of the battery 10 ( A correction value map 72 is created by examining how much the detected temperature error amount (surface temperature change amount ΔT1) is generated according to the air surface temperature difference ΔT2 that is a difference from the surface temperature TB1) without error. . The correction value map 72 is stored in the storage unit 52.

  Then, at the time of calculating the surface temperature TB1 of the battery 10 (correcting the detected temperature TB of the surface temperature sensor 34), the error amount of the detected temperature corresponding to the rotational speed N of the blower fan 12 and the air surface temperature difference ΔT2. (Surface temperature change amount ΔT1) is read from the correction value map 72 in the storage unit 52, and the detected temperature TB (surface temperature with error) of the surface temperature sensor 34 affected by the cooling air is used using the surface temperature change amount ΔT1. By correcting TB2), the surface temperature TB1 of the battery 10 is calculated.

  Therefore, accurate correction is performed in accordance with the surface temperature sensor 34 to be corrected, and in accordance with the rotational speed N of the blower fan 12 and the air surface temperature difference ΔT2, so that the surface temperature of the battery 10 is accurate. TB1 can be acquired.

  Therefore, since the accurate surface temperature TB1 of the battery 10 is provided to the cooling control unit 40 of the cooling device 50, the cooling control unit 40 accurately controls the blower fan 12 according to the surface temperature TB1 of the battery 10. Therefore, the battery 10 can be appropriately cooled.

  DESCRIPTION OF SYMBOLS 10 Battery, 12 Fan, 16 Motor, 18 Inlet, 20 Intake duct, 22 Exhaust duct, 23 Battery storage case, 24 Positive line, 26 Negative line, 28 Inverter, 30 Motor generator, 32 Air temperature sensor, 34 Surface temperature Sensor, 40 Cooling control unit, 50 Cooling device, 52 Storage unit, 54 Calculation unit, 60 Temperature calculation control unit, 70 Battery temperature calculation device, 72 Correction value map.

Claims (1)

A battery temperature calculation device for calculating a surface temperature of a battery,
A surface temperature sensor that is attached to the surface of the battery and detects the surface temperature of the battery affected by cooling air supplied from a blower fan; and
An air temperature sensor for detecting an air temperature of air supplied from the blower fan to the battery;
The surface temperature without error, which is the surface temperature of the battery, detected by the surface temperature sensor in a state not affected by the cooling air from the blower fan, and the influence of the cooling air when the blower fan is driven at a predetermined rotational speed The surface of the air that is the difference between the surface temperature change with an error detected by the surface temperature sensor and the predetermined rotational speed and the surface temperature with no error is detected by the surface temperature sensor. A storage unit for storing the temperature difference in association with;
At the time of the calculation, the air surface temperature difference is calculated from the error-free surface temperature acquired at the start of driving the blower fan and the air temperature acquired at the time, and the calculated air surface Based on the temperature difference and the rotation speed of the blower fan at the time, the corresponding surface temperature change amount is read from the storage unit, and the read surface temperature change amount is the surface with the error at the time point. A calculation unit that calculates the surface temperature of the battery by adding to the temperature,
The battery temperature calculation apparatus characterized by the above-mentioned.

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