JP2019022308A - Sensor diagnostic device - Google Patents

Abstract

To provide a sensor diagnostic device enabled to diagnose a temperature sensor provided to heat generating equipment even when a timer is abnormal.SOLUTION: The present invention relates to a sensor diagnostic device 20 which is mounted on an electric vehicle comprising on-vehicle equipment including a battery 14 charged by an external power supply and a motor 12, and diagnoses a temperature sensor 13 of heat generating equipment 12 generating heat during vehicle operation in the on-vehicle equipment and also radiating heat during soaking, the sensor diagnostic device comprising an SOC detection part 3b, a clock part 4a which measures a soaking time based upon clocking of a timer 1a measuring a time during soaking, a variation quantity detection part 4b which detects a charging rate variation quantity before and after the soaking based upon a detection result of the SOC detection part 3b, and a temperature sensor diagnostic part 4c which diagnoses the temperature sensor 13. The temperature sensor diagnostic part 4c diagnoses the temperature sensor 13 once the soaking time exceeds a predetermined time when timer information is obtained, and diagnoses the temperature sensor 13 once a charging rate variation quantity exceeds a predetermined quantity when no timer information is obtained.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a sensor diagnostic device for diagnosing a temperature sensor provided in an in-vehicle device of an electric vehicle.

The temperature of a heat-generating device (on-vehicle device) that generates heat while traveling, such as a motor or an inverter mounted on an electric vehicle, is monitored by an attached temperature sensor. A technique for detecting such a failure of the temperature sensor has been developed.
For example, the failure determination circuit disclosed in Patent Document 1 determines a plurality of temperature sensors that detect the temperature of a traveling battery, a timer that starts counting when an ignition switch is turned off, and a failure of the temperature sensor. And an arithmetic circuit.
When the temperature of the battery for traveling that has generated heat decreases (converges) to near the outside air temperature and the timer expires, the arithmetic circuit becomes an operating state. In other words, when the temperature of the battery for traveling that has generated heat has converged to near the outside air temperature, the detected temperature of any temperature sensor should converge to near the outside air temperature if it is normal. If it is different from the temperature detected by another temperature sensor, or if it is outside the preset temperature range, the arithmetic circuit determines that this temperature sensor has failed.

JP 2010-57292 A

  However, in the technique disclosed in Patent Document 1, if the timer fails, the malfunction may not be accurately determined by operating the arithmetic circuit before the temperature of the heated running battery has decreased to near the outside air temperature. There is.

The present case has been devised in view of the above-described problems, and provides a sensor diagnostic apparatus that can diagnose a temperature sensor attached to a heat generating device even when a timer becomes abnormal. With the goal.
The present invention is not limited to this purpose, and is a function and effect derived from each configuration shown in the embodiments for carrying out the invention described later, and other effects of the present invention are to obtain a function and effect that cannot be obtained by conventional techniques. Can be positioned.

(1) A sensor diagnostic device disclosed herein is mounted on an electric vehicle including an in-vehicle device including a battery charged by an external power source and an electric motor for driving, and generates heat during vehicle operation in the in-vehicle device. On the other hand, a sensor diagnostic device for diagnosing a temperature sensor provided in a heat generating device that dissipates heat during soak, an SOC detection unit that detects a charge rate of the battery, a timer that counts during the soak, and the timer A time measuring unit that measures a soak time based on a time measurement, a change amount detection unit that detects a change amount of the battery charge rate before and after the soak based on a detection result of the SOC detection unit, and a diagnosis of the temperature sensor A temperature sensor diagnosis unit.
When the timer information is obtained from the timer, the temperature sensor diagnosis unit diagnoses the temperature sensor when the soak time measured by the timer exceeds a predetermined time, and obtains the timer information from the timer. If not, the temperature sensor is diagnosed when the amount of change detected by the change amount detector exceeds a predetermined amount.

  (2) A timer diagnosis unit for diagnosing the timer is provided, and the temperature sensor diagnosis unit, when the timer diagnosis unit diagnoses that the timer is normal, the soak time measured by the timer unit for a predetermined time If the timer is diagnosed as abnormal by the timer diagnosing unit, and the change detected by the change detection unit exceeds a predetermined amount, the temperature sensor is diagnosed. It is preferable to diagnose the sensor.

  (3) An SOC detection diagnosis unit for diagnosing the SOC detection unit is provided, and the temperature sensor diagnosis unit is operated by the SOC detection diagnosis unit even when the timer diagnosis unit diagnoses that the timer is abnormal. When the SOC detector is diagnosed as abnormal, it is preferable to prohibit the temperature sensor from being diagnosed.

  (4) When the change detected by the change detection unit indicates charging of the battery, the temperature sensor diagnosis unit detects the temperature sensor based on the change detected by the change detection unit. It is preferable to diagnose.

(5) It is preferable that the temperature sensor diagnostic unit changes the predetermined amount according to the charging mode.
(6) It is preferable that the temperature sensor diagnosis unit corrects the predetermined amount by learning control when the change amount detected by the change amount detection unit indicates power supply from the battery.
(7) It is preferable that an adjustment unit is provided that adjusts the predetermined amount when the change amount detected by the change amount detection unit indicates power supply from the battery based on the change in power supply.

According to the disclosed sensor diagnostic device, when the timer is diagnosed as normal, the soak time can be directly measured by the timer based on the timer information. It is possible to accurately estimate that the heat generating device has been lowered to a temperature necessary for diagnosis of the temperature sensor, and to accurately diagnose the temperature sensor.
Even when the timer is diagnosed as abnormal by the timer diagnosis unit, it is estimated that the soak time exceeds a predetermined time based on the change amount of the charging rate before and after the soak detected by the change amount detection unit (indirect The temperature sensor can be diagnosed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic side view showing a vehicle equipped with a sensor diagnostic device according to an embodiment and a configuration around the vehicle. It is a schematic diagram which shows the vehicle by which the sensor diagnostic apparatus which concerns on embodiment is equipped. It is a block diagram which shows the structure of the sensor diagnostic apparatus which concerns on embodiment. It is an example of the flowchart for demonstrating the flow of the diagnosis of the temperature sensor by the sensor diagnostic apparatus which concerns on embodiment.

  Embodiments of the present invention will be described below with reference to the drawings. Note that the embodiment described below is merely an example, and there is no intention to exclude various modifications and technical applications that are not explicitly described in the following embodiment. The configurations of the following embodiments can be implemented with various modifications without departing from the spirit thereof.

[1. Vehicle configuration]
The sensor diagnostic apparatus of this embodiment is mounted on the vehicle 10 shown in FIG. First, a schematic configuration of the vehicle 10 will be described with reference to FIG.
The vehicle 10 is an electric vehicle provided with various in-vehicle devices including a battery 14 and an electric motor 12 for driving (hereinafter referred to as “motor 12”) in addition to the engine 11 for driving. The motor 12 uses electric power stored in the battery 14 as a power source.
Furthermore, in the present embodiment, the vehicle 10 is a plug-in hybrid electric vehicle (PHEV) that can directly supply power from an external power source such as a household power source or a charging station.

  In the example shown in FIG. 1, a household power source is connected by connecting the outlet 102 of the charging box 101 attached to the wall surface of the house 100 and the charging / discharging connector 10a of the vehicle 10 by a charging cable 103 with a plug. The battery 14 is being charged. On the contrary, the electric power stored in the battery 14 is supplied from the charging / discharging connector 10a to the electric appliance in the house 100 via the charging cable 103, the outlet 102 and the charging box 101 (so-called V2H <Vehicle to Home>). Power supply).

Next, the configuration of the vehicle 10 will be further described with reference to FIG.
The vehicle 10 is provided with a transaxle 15 and a generator (generator) 16 in addition to the engine 11, the motor 12, and the battery 14, and a PHEV-ECU 1 (Plug-in Hybrid Electric Vehicle-Electronic Control Unit). Control units of an engine ECU 2 (Engine Electronic Control Unit), a BMU 3 (Battery Management Unit), an MCU 4 (Motor Control Unit), and a GCU 5 (Generator Control Unit) are provided.

  The driving force of the engine 11 and the motor 12 is transmitted to the driving wheel among the wheels 17 via the transaxle 15 to cause the vehicle 10 to travel.

  The motor 12 is an electric motor that generates power by receiving supply of electric power from the battery 14 or electric power generated by the generator 16. The motor 12 operates as a generator when the vehicle 10 travels at a constant speed or decelerates, and is driven to generate electricity (regenerative drive). At this time, the kinetic energy due to the rotation of the drive wheels is transmitted to the motor 12 and converted into AC power in the motor 12. The AC power is converted into DC power by an inverter (not shown) included in the MCU 4 and then charged to the battery 14.

  The generator 16 is a generator that generates power with the output of the engine 11. The electric power generated by the generator 16 is converted into DC power by an inverter (not shown) included in the GCU 5 and then charged to the battery 14 or directly supplied to the motor 12 to supply power to the motor 12. Used as.

  The inverters included in the MCU 4 and the GCU 5 are respectively interposed on a power supply circuit that connects the motor 12 and the battery 14 and a power supply circuit that connects the generator 16 and the battery 14. As described above, the battery 14 is a power storage device that can charge an external power source exemplified by a household power source, regenerative power generated by the vehicle 10, and power generated by the generator 16.

  The transaxle 15 is a power transmission device provided with a final reduction gear including a differential device, and incorporates a plurality of mechanisms responsible for power transmission between the engine 11 and the motor 12 as drive sources and the drive wheels.

[2. Control configuration]
[2-1. Outline of electronic control unit]
Next, an outline of the electronic control device will be described with reference to FIG.
The vehicle 10 is provided with a plurality of electronic control devices connected via a communication line (not shown). The vehicle 10 is provided with the above-described PHEV-ECU 1, engine ECU 2, BMU 3, MCU 4 and GCU 5 as electronic control units.
These electronic control units are configured as LSI devices or embedded electronic devices in which a known microprocessor, ROM, RAM, or the like is integrated.

  The engine ECU 2 is an electronic control unit that controls a wide range of systems such as an ignition system, a fuel system, an intake / exhaust system, and a valve system related to the engine 11. The amount of air and fuel injection supplied to each cylinder of the engine 11. And ignition timing and the like.

The BMU 3 is an electronic control device for managing the battery 14. As will be described later, the BMU 3 includes an SOC detection unit 3b (see FIG. 3) that calculates and detects the charging rate (SOC) of the battery 14 as an internal function.
The MCU 4 is an electronic control device that receives a control signal from the PHEV-ECU 1 and converts the power of the battery 14 by an inverter to drive the motor 12. In this embodiment, the motor 12 is configured as a three-phase motor, and the temperature of each phase of the U phase, the V phase, and the W layer is detected by the temperature sensors 13a, 13b, and 13c. Hereinafter, when the temperature sensors 13a, 13b, and 13c are not distinguished from each other, they are referred to as a temperature sensor 13.

The MCU 4 acquires the detection results of these temperature sensors 13 and monitors the state of the motor 12 according to these detection results.
The GCU 5 is an electronic control unit that receives the control signal from the PHEV-ECU 1 and controls the inverter so that a DC current suitable for supply to the battery 14 can be obtained regardless of changes in the amount of power generated by the generator 16. .

  The PHEV-ECU 1 is a higher-level electronic control device than the other electronic control devices 2 to 5, and has a function of comprehensively managing the engine ECU 2, BMU 3, MCU 4, and GCU 5. The PHEV-ECU 1 controls the engine 11 via the engine ECU 2, acquires information about the engine 11, manages the battery 14 via the BMU 3, acquires information about the battery 14, and operates the motor 12 via the MCU 4. And information on the motor 12 is acquired. The PHEV-ECU 1 includes a timer 1a as an internal function used for diagnosis of temperature sensors 13a, 13b, and 13c (see FIGS. 2 and 3) attached to the motor 12, as will be described later.

Here, the engine ECU 2, BMU 3, and MCU 4 are in an operating state while a key switch (not shown) of the vehicle 10 is ignited and the traveling system including the motor 12 is turned on (hereinafter referred to as “vehicle in operation”). While the key switch is turned off and the traveling system is turned off (hereinafter referred to as “soaked”), the supply of electric power is stopped and the operation is disabled. On the other hand, the PHEV-ECU 1 is supplied with electric power during soaking as well as during vehicle operation. That is, electric power is always supplied to the PHEV-ECU 1.
Here, the soak refers to a state in which the PHEV-ECU 1 is kept on by turning off the key switch, but the MCU 4 is turned off (BMU 3 is also turned off in this embodiment). In other words, it refers to a standby state for radiating heat until the temperature of the heat generating device becomes constant (thermal equilibrium state) until the next vehicle operation.

[2-2. Configuration of sensor diagnostic device]
Hereinafter, with reference to FIG. 3, the sensor diagnostic device 20 will be described while further explaining the configurations of the PHEV-ECU 1, the BMU 3 and the MCU 4.
In this embodiment, the sensor diagnostic device 20 diagnoses whether the temperature sensor 13 attached to the motor 12 is normal or malfunctioning. In addition, when the abnormality of the temperature sensor 13 is diagnosed by the sensor diagnostic device 20, for example, a notification unit installed in the passenger compartment notifies that the temperature sensor 13 is abnormal.
The sensor diagnostic device 20 includes a timer 1a, a timer diagnostic unit 1b, a soak time counting unit 4a (timer unit), an SOC change amount detection unit 4b (change amount detection unit), a temperature sensor diagnosis unit 4c, an SOC detection diagnosis unit 3a, and an SOC. A detection unit 3b is provided.

  Both the timer 1a and the timer diagnosis unit 1b are internal functions of the PHEV-ECU 1. Since the PHEV-ECU 1 is constantly supplied with electric power as described above, the timer 1a and the timer diagnosis unit 1b are always operating. That is, the timer 1a counts (measures time) even during the soak, and the timer diagnosis unit 1b diagnoses whether the timer 1a is operating normally even during the soak. The timer diagnosis unit 1b periodically acquires and monitors the timer information of the timer 1a. For example, when the timer information is not output from the timer 1a, when the timer information runs backward in time, The timer 1a diagnoses that it is abnormal when the signal indicating the noise includes noise, and otherwise diagnoses it as normal.

Both the SOC detection diagnosis unit 3a and the SOC detection unit 3b are internal functions of the BMU 3.
The SOC detection unit 3b periodically detects the charging rate of the battery 14.
The SOC detection diagnosis unit 3a periodically acquires and monitors the SOC information of the SOC detection unit 3b. For example, when the SOC information is not output from the SOC detection unit 3b, the SOC information has an unrealistic value. In the case where it is shown, the SOC detection unit 3b diagnoses it as abnormal, and otherwise diagnoses it as normal.

The soak time counting unit 4a, the SOC change amount detection unit 4b, and the temperature sensor diagnosis unit 4c are internal functions of the MCU 4, respectively.
The soak time counting unit 4a periodically acquires timer information from the timer 1a. The soak time counting unit 4a includes a non-volatile memory, sequentially stores the acquired timer information, and the current timer information T (n) acquired this time and the previous timer information T (n-1) acquired last time. Calculate the difference.

  As described above, during the soak, the MCU 4 is not supplied with power and is turned off, and the soak time counting unit 4a that is an internal function of the MCU 4 is also turned off. On the other hand, the timer 1a also counts during the soak. Therefore, at the time of soaking, the soak time counting unit 4a stores the timer information immediately after the end of the soak and the timer information just before the start of the soak as the current timer information T (n) and the previous timer information T (n-1). The difference in the timer information is measured as the soak time Ts [= T (n) −T (n−1)].

The SOC change amount detection unit 4b periodically acquires the SOC information from the SOC detection unit 3b. The SOC change amount detection unit 4b includes a non-volatile memory and sequentially stores the acquired SOC information. The current SOC information S (n) acquired this time and the previous SOC information S (n−1) acquired last time [= S (n) −S (n−1)] is calculated.
The SOC change amount detection unit 4b, which is an internal function of the MCU 4, is in an off state during the soak, like the above-described soak time counting unit 4a. Therefore, at the time of the soak, the SOC information immediately after the end of the soak and the SOC immediately before the start of the soak Information is stored as current SOC information S (n) and previous SOC information S (n−1), and the difference between these SOC information is measured as the SOC change amount ΔS in the soak.

  The temperature sensor diagnosis unit 4c diagnoses whether the temperature sensor 13 is normal or abnormal (failure). In addition to the heat generating device that generates heat during operation of the motor 12 during vehicle operation, the heat generation temperature may vary depending on the part. For this reason, it is difficult to diagnose the temperature sensors 13a, 13b, and 13c based on the detected temperature difference and the detected temperature level during vehicle operation with heat generation. Accordingly, the temperature sensor diagnosis unit 4c determines that the temperature sensor 13a is based on each detected value after a sufficient soak time has elapsed, the motor 12 is naturally cooled, and the temperature of each part converges to near the outside air temperature. , 13b, 13c are diagnosed.

Specifically, for example, the detected values of the temperature sensors 13a, 13b, and 13c are compared, and the detected value differs from the detected value of the other temperature sensor 13 by a predetermined value or more (the characteristic is abnormal). The temperature sensor) may be determined to be abnormal. Alternatively, an average value of the detection values of the temperature sensors 13a, 13b, and 13c may be calculated, and the temperature sensor 13 having a detection value that is more than a predetermined value away from the average value may be determined to be abnormal.
Alternatively, the temperature sensor 13 whose detected value is more than a predetermined value away from a predetermined threshold value may be determined to be abnormal. In this case, the threshold value may be set to a predetermined value, or the threshold value may be changed based on a detection result of an intake air temperature sensor or another sensor that detects an outside air temperature. The predetermined value is, for example, a value determined in consideration of the maximum variation value with respect to an expected normal detection value.
By these methods, it is possible to diagnose that the temperature sensor 13 having abnormal characteristics is malfunctioning.

Here, in the temperature sensor diagnosis unit 4c, normally, the soak time Ts measured by the soak time measuring unit 4a exceeds a predetermined time Ts0 required for cooling the motor 12 (hereinafter referred to as “required cooling time Ts0”). Then, it is determined that the temperature tm of the motor 12 (hereinafter referred to as “motor temperature tm”) has dropped to a temperature t0 (hereinafter referred to as “diagnosis temperature t0”) suitable for diagnosis of the temperature sensor 13. However, when the timer 1a is not normal, the reliability of the soak time Ts measured based on the timer information of the timer 1a is low, or the soak time Ts cannot be measured. 13 is not reliable or the temperature sensor 13 cannot be diagnosed.
Therefore, the temperature sensor diagnosis unit 4c determines that the soak time Ts is the required cooling time when the timer diagnosis unit 1b diagnoses that the timer 1a is not normal and the SOC detection diagnosis unit 3a diagnoses the SOC detection unit 3b as normal. Whether or not Ts0 is exceeded is determined based on the SOC change amount ΔS during the soak.

  Here, if the SOC change amount ΔS in the soak measured by the SOC change amount detection unit 4b is positive (ΔS> 0), the temperature sensor diagnosis unit 4c is charged in the soak, and the SOC change amount ΔS. And the charging time and hence the soak time Ts are considered to be in a proportional relationship. And if the absolute value of SOC variation | change_quantity (DELTA) S exceeds predetermined amount (DELTA) S0 (+), the temperature sensor diagnostic part 4c will determine with the soak time Ts exceeding the required cooling time Ts0.

Further, if the SOC change amount ΔS in the soak is negative (ΔS <0), power is supplied from the battery 14 to, for example, the appliance in the house 100 during the soak, and the SOC change amount ΔS and the power supply time and thus the soak time Ts Is considered to be proportional. And if the absolute value of this SOC variation | change_quantity (DELTA) S exceeds predetermined amount (DELTA) S0 (-), the temperature sensor diagnostic part 4c will determine with the soak time Ts exceeding the required cooling time Ts0.
Hereinafter, when the predetermined amounts ΔS0 (+) and ΔS0 (−) are not distinguished, they are expressed as the predetermined amount ΔS0.

  In addition, when the vehicle 10 can be charged in the quick charge mode, which is faster than the normal charge mode, in addition to the charge in the normal charge mode, the normal charge mode is used even if the SOC change amount ΔS is the same amount. And the rapid charging mode differ in the elapsed charging time and thus the expected soak time Ts. Therefore, by changing the predetermined amount ΔS0 (+) during charging according to the charging mode, it is accurately estimated whether or not the soak time Ts exceeds the required cooling time Ts0 regardless of the difference in charging speed. it can.

Specifically, for example, the PHEV-ECU 1 identifies the charging mode based on the SOC change amount ΔS per unit time, and this identification information is acquired by the MCU 4 after the soak is completed, and the predetermined amount ΔS 0 ( +) Is set.
Further, since the charging efficiency changes depending on the SOC at the start of charging and the usage time of the battery 14, the elapsed charging time also changes even if the SOC change amount ΔS is the same amount. Therefore, the predetermined amount ΔS0 (+) may be changed according to the SOC at the start of charging and the usage time of the battery 14.

In addition, when power is supplied from the battery 14 to the electrical appliances in the house 100, the amount of power supply (consumption) per unit time according to various conditions such as family structure (number of family members, age, etc.), season, time zone, day of the week, etc. Therefore, even if the SOC change amount ΔS is the same amount, the elapsed power supply time and the expected soak time Ts are also different.
Therefore, for example, means for inputting the condition or the means for inputting the condition so that a predetermined amount ΔS0 (−) can be set according to the condition by inputting at least one of the various conditions to the PHEV-ECU 1 or the MCU 4. An adjustment unit such as means for directly inputting the predetermined amount ΔS0 (−) may be provided in the vehicle interior.

Alternatively, the PHEV-ECU 1 and the MCU 4 may automatically set the predetermined amount ΔS0 (−) by learning control. That is, every time power is supplied from the battery 14, the PHEV-ECU 1 or MCU 4 stores the power supply amount and various conditions as described above, and learns the relationship between the power supply amount and these conditions. The predetermined amount ΔS0 (−) is automatically set based on the above.
In this way, by setting the power supply amount according to various conditions, the predetermined amount ΔS0 (−) can be set to an appropriate value, and whether or not the soak time Ts exceeds the required cooling time Ts0 is accurately determined. It can be estimated well.

  However, when the timer diagnostic unit 1b diagnoses that the timer 1a is not normal and the SOC detection diagnostic unit 3a diagnoses that the SOC detection unit 3b is not normal (abnormal), the sensor diagnostic device 20 13 diagnostics are prohibited. That is, when neither the timer information for estimating the soak time nor the SOC change amount ΔS can be obtained, the temperature sensor diagnosis unit 4c has the temperature from the viewpoint that the diagnosis accuracy of the temperature sensor 13 cannot be ensured. The sensor 13 is not diagnosed.

[3. flowchart]
FIG. 4 is an example of a flowchart for explaining the flow of diagnosis of the temperature sensor 13 by the sensor diagnostic device 20.
This flowchart is started when the ignition is turned on, and is repeatedly executed at a preset predetermined control cycle.

As shown in FIG. 4, in step S10, the timer diagnosis unit 1b diagnoses whether or not the timer 1a is normal. If the timer 1a is diagnosed as normal, the process proceeds to step S20, and if the timer 1a is diagnosed as abnormal. Proceed to step S110.
When the timer information T (n) is stored by the soak time counting unit 4a in step S20, the process proceeds to step S30, where the current timer information T (n) stored in the current control cycle is stored by the soak time counting unit 4a. The difference from the previous timer information T (n-1) stored in the previous control cycle is calculated. If the key switch is turned off between the current control cycle and the previous control cycle, this difference becomes the soak time Ts.

  In step S40, it is determined whether or not the soak time Ts exceeds the necessary cooling time Ts0. If the soak time Ts exceeds the required cooling time Ts0, it is determined that the motor temperature tm has decreased and converged to the diagnosis temperature t0, the process proceeds to step S50, the temperature sensor 13 is diagnosed, and the process returns. If the soak time Ts does not exceed the required cooling time Ts0, it is determined that the motor temperature tm has not decreased or converged to the diagnosis temperature t0, the process proceeds to step S60, and the temperature sensor 13 returns without being diagnosed (this control cycle ends). To do.

When the process proceeds from step S10 to step S110, the SOC detection diagnosis unit 3a diagnoses whether or not the SOC detection unit 3b is normal. If the SOC detection unit 3b is diagnosed as normal, the process proceeds to step S120, and the SOC detection unit 3b is abnormal. If it is diagnosed, the process proceeds to step S160.
When the SOC change amount detection unit 4b stores the SOC information S (n) in step S120, the process proceeds to step S130, and the SOC change amount detection unit 4b determines the current SOC information S (n) in the current control cycle and the previous time. A difference from the previous SOC information S (n-1) stored in the control cycle is calculated. If the key switch is turned off between the current control cycle and the previous control cycle, this difference becomes the SOC change amount ΔS before and after the soak.

  In step S140, it is determined whether or not the absolute value (= | ΔS |) of the SOC change amount ΔS exceeds a predetermined amount ΔS0. Specifically, if the SOC change amount ΔS is positive, it is determined whether or not the SOC change amount ΔS deviates from the predetermined amount ΔS0 (+). If the SOC change amount ΔS is negative, it is negative than the predetermined amount ΔS0 (−). It is determined whether or not it is off.

If the absolute value of the SOC change amount ΔS exceeds the predetermined amount ΔS0, it is assumed that the soak time Ts exceeds the required cooling time Ts0, and as a result, the motor temperature tm is lowered and converged to the diagnosis temperature t0, step S150. The temperature sensor 13 is diagnosed and the process returns. If the absolute value of the SOC change amount ΔS does not exceed the predetermined amount ΔS0, the process proceeds to step S160, where it is assumed that the soak time Ts has not reached the required cooling time Ts0, and the motor temperature tm is lowered and converged to the diagnostic temperature t0. If not, the temperature sensor 13 returns without being diagnosed.
If the SOC detection unit 3b is diagnosed as abnormal in step S110, the soak time Ts cannot be estimated based on the SOC change amount ΔS, and the temperature sensor 13 cannot be diagnosed, and the process proceeds to step S160. Prohibit diagnosis and return.

[4. Action / Effect]
According to the sensor diagnostic apparatus 20 of one embodiment of the present invention, the following operational effects can be obtained.
(1) When the timer diagnostic unit 1b diagnoses that the timer 1a is normal, the soak time counting unit 4a can directly count the soak time Ts based on the timer information of the timer 1a. However, it is possible to accurately estimate that the motor temperature tm has decreased to the diagnosis temperature t0 beyond the necessary cooling time Ts0, and thus to accurately diagnose the temperature sensor 13 on the condition that the motor temperature tm has decreased to the diagnosis temperature t0. Can do.
Even when the timer diagnosis unit 1b diagnoses that the timer 1a is abnormal, the soak time Ts exceeds the required cooling time Ts0 based on the SOC change amount ΔS before and after the soak detected by the SOC change amount detection unit 4b. Therefore, the temperature sensor 13 can be diagnosed.

(2) Even when the timer diagnostic unit 1c diagnoses the timer 1a as abnormal, when the SOC detection diagnostic unit 3a diagnoses the SOC detection unit 3b as abnormal, the sensor diagnostic device 20 is a temperature sensor. Therefore, inappropriate diagnosis can be suppressed based on the abnormality information detected by the SOC detector 3b.
(3) When the SOC change amount ΔS is positive (ΔS> 0), that is, when the battery 14 is charged, that is, when the battery 14 is charged, the charging speed varies less than the power supply speed. The soak time Ts can be estimated with high accuracy, and the temperature sensor 13 can be diagnosed with high accuracy as compared with the case where power is supplied from the battery 14.

(4) When the predetermined amount ΔS0 for estimating whether or not the soak time Ts exceeds the required cooling time Ts0 is changed according to the charging mode, the soak time Ts can be estimated with high accuracy. As a result, the temperature sensor 13 can be diagnosed with high accuracy.
(5) When the SOC change amount ΔS is negative (ΔS <0), that is, when power is supplied from the battery 14, the temperature sensor diagnosis unit 4c is based on the SOC change amount ΔS because the power supply speed varies depending on various conditions. The estimation accuracy of the soak time Ts is lower than when the battery 14 is charged. However, the predetermined amount ΔS0 (−) is corrected by learning control, or an adjustment unit is provided to correct the predetermined amount ΔS0 (−) by the adjusting unit, thereby absorbing the difference in power supply speed due to various conditions. And the estimation accuracy of the soak time Ts can be improved.

[5. Others]
(1) The sensor diagnostic apparatus of the present invention is not limited to the diagnosis of the temperature sensor 13 of the motor 12. In other words, a temperature sensor that monitors an in-vehicle device (heat generating device) that generates heat during vehicle operation waits for the temperature of the in-vehicle device to drop to a diagnosis temperature during soaking, so it is limited only during vehicle operation. If it is a temperature sensor provided in a heat generating device that generates heat (in other words, an on-vehicle device that generates heat during vehicle operation and is naturally cooled without generating heat during soak), the sensor diagnosis of the present invention The device can be a diagnostic target. For example, the sensor diagnostic device of the present invention can be applied to diagnosis of a temperature sensor provided in an inverter (thermal equipment) included in MCU 4 or GCU 5.

(2) The timer diagnosis unit 1b is not necessarily an internal function of the PHEV-ECU 1, and may be configured as an internal function of the MCU 4, for example. Thereby, not only diagnosis of the timer 1a itself but also diagnosis including communication trouble between the timer 1a and the MCU 4 can be performed.
(3) The timer diagnosis unit 1b may be omitted. When the timer diagnosis unit 1b is omitted, the temperature sensor diagnosis unit 4c determines that the SOC change amount ΔS detected by the SOC change amount detection unit 4b exceeds the predetermined amount ΔS0 when timer information is not obtained from the timer 1a. If so, the temperature sensor 13 is diagnosed.
The time when the timer information cannot be obtained includes the time when the signal indicating the timer information itself is not obtained and the time when the signal indicating the timer information is abnormal, that is, when the normal signal cannot be obtained.

(4) The sensor diagnostic device of the present invention can also be applied to the diagnosis of a temperature sensor provided in only one single heat generating device. In this case, among the above-described temperature sensor diagnosis methods, a method of determining that a failure has occurred when a detected value is different from a predetermined threshold by a predetermined value or more can be applied.
(5) During the soak, if the timer value of the timer 1a reaches the upper limit and is reset to zero (zero), the soak time cannot be measured by the timer 1a. For this reason, even when the timer is reset during the soak, the temperature sensor may be diagnosed based on the SOC change ΔS. Specifically, the PHEV-ECU 1 stores the reset information to that effect when the timer 1a is reset, and transmits this reset information to the temperature sensor diagnostic unit 4c of the MCU 4 after the soak is completed.

(6) In the above embodiment, the diagnosis of the temperature sensor 13 using the SOC change amount ΔS is illustrated both when the battery 14 is charged and when the power is supplied. However, the SOC is only charged when the battery 14 is charged or only when the power is supplied. The temperature sensor may be diagnosed using the change amount ΔS.
(7) The sensor diagnostic apparatus of the present invention can be applied to any electric vehicle including a battery charged by an external power source and a driving electric motor. For example, the electric motor without a driving engine is provided. It can also be applied to an electric vehicle that travels alone.

1 PHEV-ECU
1a Timer 1b Timer diagnostic unit 3 BMU
3a SOC detection diagnostic unit 4 MCU
4a Soak time counter (time counter)
4b SOC change amount detection unit (change amount detection unit)
4c Temperature sensor diagnostic unit 10 Vehicle (electric vehicle)
12 Electric motor (vehicle equipment, heat generating equipment)
13, 13a, 13b, 13c Temperature sensor 14a SOC detector 14 Battery Ts Soak time Ts0 Required cooling time (predetermined time)
T (n), T (n-1) Timer information ΔS SOC change amount (charge rate change amount)
ΔS0, ΔS0 (+), ΔS0 (−) predetermined amount tm motor temperature t0 diagnostic temperature t0

Claims (7)

Provided in an electric vehicle equipped with an in-vehicle device including a battery charged by an external power source and an electric motor for driving, provided in the exothermic device that generates heat during operation of the vehicle while dissipating heat in the soak. A sensor diagnostic device for diagnosing a temperature sensor,
An SOC detector for detecting a charging rate of the battery;
A timer for timing during the soak;
A timer unit for measuring the soak time based on the time of the timer;
A change amount detection unit that detects a change amount of the charging rate of the battery before and after the soak based on a detection result of the SOC detection unit;
A temperature sensor diagnostic unit for diagnosing the temperature sensor;
When the timer information is obtained from the timer, the temperature sensor diagnosis unit diagnoses the temperature sensor when the soak time measured by the timer exceeds a predetermined time, and obtains the timer information from the timer. If not, the temperature sensor is diagnosed when the amount of change detected by the change amount detector exceeds a predetermined amount. A timer diagnosis unit for diagnosing the timer;
The temperature sensor diagnosis unit diagnoses the temperature sensor if the soak time measured by the timer unit exceeds a predetermined time when the timer diagnosis unit diagnoses that the timer is normal, and the timer The temperature sensor is diagnosed when the amount of change detected by the change amount detection unit exceeds a predetermined amount when the timer is diagnosed as abnormal by the diagnosis unit. Sensor diagnostic device. An SOC detection diagnosis unit for diagnosing the SOC detection unit;
The temperature sensor diagnosis unit diagnoses the temperature sensor when the SOC detection diagnosis unit diagnoses the abnormality as the abnormality even when the timer diagnosis unit diagnoses the timer as an abnormality. The sensor diagnosis apparatus according to claim 2, wherein the sensor diagnosis apparatus is prohibited. The temperature sensor diagnosis unit diagnoses the temperature sensor based on the change amount detected by the change amount detection unit when the change amount detected by the change amount detection unit indicates charging of the battery. The sensor diagnostic apparatus according to any one of claims 1 to 3, wherein The sensor diagnosis device according to claim 4, wherein the temperature sensor diagnosis unit changes the predetermined amount according to the charging mode. The temperature sensor diagnosis unit corrects the predetermined amount by learning control when the change amount detected by the change amount detection unit indicates power supply from the battery. The sensor diagnostic device according to any one of the above. The adjustment part which adjusts based on the fluctuation | variation of the said electric power feeding about the said predetermined amount in case the variation | change_quantity detected by the said variation | change_quantity detection part shows the electric power feeding from the said battery is provided. The sensor diagnostic device according to claim 6.

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