WO2018173936A1

WO2018173936A1 - Abnormality diagnosis device

Info

Publication number: WO2018173936A1
Application number: PCT/JP2018/010342
Authority: WO
Inventors: 明生中島
Original assignee: Ntn株式会社
Priority date: 2017-03-23
Filing date: 2018-03-15
Publication date: 2018-09-27
Also published as: JP2018159625A

Abstract

Provided is an abnormality diagnosis device that diagnoses abnormalities in temperature sensors provided to a vehicle having left and right motor drive devices, wherein abnormalities in the temperature sensors can be individually assessed. This abnormality diagnosis device assesses abnormalities of left and right independently driven temperature sensors provided to a vehicle. Left and right motor temperature sensors (SaL, SaR) and left and right cooling oil temperature sensors (SbL, SbR) are provided as temperature sensors. Also provided are: a temperature comparison means (23) for comparing two prescribed temperatures to each other, these being either the two motor temperatures or the two cooling oil temperatures, during an initial diagnosis; a paired average value comparison means (26) for comparing the average values of all temperatures with the temperatures sensed by the sensors; and a temperature sensor individual abnormality assessment means (25) for individually assessing whether or not there are any abnormalities in the temperature sensors (SaL, SaR, SbL, SbR) from the result of the comparison made by the temperature comparison means (23) and the result of the comparison made by the paired average value comparison means (26).

Description

Abnormality diagnosis device

Related applications

This application claims the priority of Japanese Patent Application No. 2017-057043 filed on Mar. 23, 2017, which is incorporated herein by reference in its entirety.

The present invention relates to an abnormality diagnosis device, and more particularly to an abnormality diagnosis device that diagnoses an abnormality of a temperature sensor provided in a vehicle using a plurality of motors as drive sources.

Conventionally, a vehicle including a motor temperature sensor that detects a motor temperature using a motor as a drive source is known. And the abnormality detection apparatus which detects abnormality of a motor temperature sensor is proposed (for example, patent documents 1). The abnormality detection apparatus of Patent Document 1 includes a motor temperature sensor and a cooling water temperature sensor that detects the temperature of cooling water that cools the motor and the like. In this abnormality detection device, when the vehicle is stopped, the current characteristics calculated as a linear function of the relationship between the motor temperature detected by each sensor and the coolant temperature, and the normal motor temperature and coolant temperature stored in advance are calculated. The deterioration state of the motor temperature sensor is determined by comparing the normal characteristic calculated as a linear function with the relationship.

In addition, in an in-wheel motor drive device that independently drives the left and right wheels, it is difficult to pipe cooling water from the vehicle to the in-wheel motor drive device, so the motor is cooled with cooling oil and the cooling oil is in-holed. Conventionally, a structure for cooling with running wind in a motor has been used.

Japanese Unexamined Patent Publication No. 2016-125960

In Patent Document 1, when an abnormality occurs in the cooling water temperature sensor, the deterioration state of the motor temperature sensor cannot be determined. Further, when it is unknown whether the cooling water temperature sensor is normal or abnormal, the motor temperature sensor cannot be determined to be abnormally objective.

The in-wheel motor drive device includes, for example, a motor temperature sensor that detects the temperature of the motor and a cooling oil temperature sensor that detects the temperature of the cooling oil that cools the motor in order to monitor the temperature of the motor. Considering the case where an abnormality occurs in the temperature sensor, it is ideal to arrange a large number of these temperature sensors for the in-wheel motor drive device. However, in terms of cost, it is desired to use one motor temperature sensor and one cooling oil temperature sensor for the in-wheel motor drive device. In that case, it is difficult to verify the measured values of the temperature sensors individually in determining abnormality or deterioration of each temperature sensor, compared to the case where a large number of temperature sensors are arranged.

An object of the present invention is to provide an abnormality diagnosis device for diagnosing abnormality of a temperature sensor provided in a vehicle equipped with left and right motor drive devices, and capable of individually determining the abnormality of each temperature sensor. It is to be.

Hereinafter, in order to facilitate understanding, description will be made with reference to the reference numerals of the embodiments.

In the abnormality diagnosis device according to the first configuration of the present invention, the temperatures of the motors 6 of the left and right motor drive devices in a vehicle having left and right motor drive devices for independently driving the left and

right wheels

2 and 2 are respectively determined. An abnormality in the left and right motor temperature sensors S _aL and S _aR to be detected and an abnormality in the left and right cooling oil temperature sensors S _bL and S _bR that respectively detect the temperatures of the respective cooling oils for cooling the left and right motor driving devices, An abnormality diagnosing device for diagnosing an initial diagnosis that is within a certain period of time before the vehicle starts running from when the vehicle is turned on,
Of the two motor temperatures detected by the left and right motor temperature sensors S _aL and S _aR and the two cooling oil temperatures detected by the left and right cooling oil temperature sensors S _bL and S _bR , Temperature comparison means 23 for comparing temperatures;
The temperatures of the two motors 6 detected by the left and right motor temperature sensors S _aL and S _aR , and the two cooling oil temperatures detected by the left and right cooling oil temperature sensors S _bL and S _bR , A pair average value comparison means 26 for comparing the left and right motor temperature sensors S _aL and S _aR and the average value of the temperatures detected by the left and right cooling oil temperature sensors S _bL and S _bR ;
The left and right motor temperature sensors S _aL and S _aR and the left and right cooling oil temperature sensors S _bL and S _bR are respectively determined based on the comparison result by the temperature comparison unit 23 and the comparison result by the paired average value comparison unit 26. Temperature sensor individual abnormality determining means 25 for determining whether there is any abnormality.

The predetermined time is a time appropriately determined by design or the like, for example, a short time of about 300 milliseconds.

The two predetermined temperatures are temperatures appropriately determined by design or the like, and are determined by obtaining appropriate temperatures by one or both of tests and simulations, for example.

According to this configuration, during the initial diagnosis of the vehicle, the temperature comparison unit 23 compares two predetermined temperatures among the two motor temperatures and the two cooling oil temperatures. At the time of the initial diagnosis, the paired average value comparison means 26 is detected by each of the two motor temperatures and the two cooling oil temperatures, and the motor temperature sensors S _aL and S _aR and the cooling oil temperature sensors S _bL and S _bR. Compare the average temperature. The temperature sensor individual abnormality determination unit 25 determines the motor temperature sensors S _aL and S _aR and the cooling oil temperature sensors S _bL and S _bR from the comparison result by the temperature comparison unit 23 and the comparison result by the paired average value comparison unit 26. The presence or absence of each abnormality is judged.

For example, the temperature sensor individual abnormality determination means 25 has the same two temperatures compared by the temperature comparison means 23 and the average values of all the temperatures compared by the respective average values comparison means 26. If it is, it is determined that there is no abnormality in each of the temperature sensors S _aL , S _aR , S _bL , S _bR . In the temperature sensor individual abnormality determination unit 25, for example, when only the temperature detected by one temperature sensor is significantly smaller than the average value, it is determined that the temperature sensor has an abnormality. In this way, the abnormality of each temperature sensor S _aL , S _aR , S _bL , S _bR can be individually determined using the existing temperature sensors S _aL , S _aR , S _bL , S _bR . For temperature sensors determined to be abnormal, measures such as not being used for temperature detection can be taken.

In the abnormality diagnosis device according to the second configuration of the present invention, the temperatures of the motors 6 of the left and right motor drive devices in a vehicle having left and right motor drive devices for independently driving the left and

right wheels

2 and 2 are respectively determined. An abnormality in the left and right motor temperature sensors S _aL and S _aR to be detected and an abnormality in the left and right cooling oil temperature sensors S _bL and S _bR that respectively detect the temperatures of the respective cooling oils for cooling the left and right motor driving devices, An abnormality diagnosing device for diagnosing an initial diagnosis that is within a certain period of time before the vehicle starts running from when the vehicle is turned on,
The vehicle includes an air temperature sensor Sd that detects an outside air temperature of the vehicle,
Of the two motor temperatures detected by the left and right motor temperature sensors S _aL and S _aR and the two cooling oil temperatures detected by the left and right cooling oil temperature sensors S _bL and S _bR , Temperature comparison means 23 for comparing the temperatures with each other according to predetermined conditions;
The two motor temperatures detected by the left and right motor temperature sensors S _aL and S _aR and the two cooling oil temperatures detected by the left and right cooling oil temperature sensors S _bL and S _bR , respectively. Outside air temperature comparing means 24 for comparing the outside air temperature detected by the air temperature sensor Sd;
The abnormalities of the left and right temperature sensors S _aL and S _aR and the left and right cooling oil temperature sensors S _bL and S _bR based on the comparison result by the temperature comparison unit 23 and the comparison result by the outside air temperature comparison unit 24, respectively. Temperature sensor individual abnormality determining means 25 for determining the presence or absence of

The predetermined conditions are conditions appropriately determined by design or the like, and are determined by obtaining appropriate conditions by, for example, one or both of testing and simulation.

According to this configuration, during the initial diagnosis of the vehicle, the temperature comparison unit 23 compares two predetermined temperatures among the two motor temperatures and the two cooling oil temperatures. At the time of the initial diagnosis, the outside air temperature comparing means 24 compares the temperatures of the two motor temperatures and the two cooling oil temperatures with the outside air temperature detected by the air temperature sensor Sd. The temperature sensor individual abnormality determination unit 25 determines whether the motor temperature sensors S _aL and S _aR and the cooling oil temperature sensors S _bL and S _bR are based on the comparison result by the temperature comparison unit 23 and the comparison result by the outside air temperature comparison unit 24. Determine the presence or absence of each abnormality.

For example, when the two temperatures compared by the temperature comparison unit 23 are about the same and the temperatures compared by the outside air temperature comparison unit 24 are significantly higher than the outside air temperature, the temperature sensor individual abnormality determination unit 25 It is determined that there is no abnormality in S _aL , S _aR , S _bL , and S _bR . In the temperature sensor individual abnormality determination unit 25, for example, when the temperatures detected by the temperature sensors S _aL , S _aR , S _bL , and S _bR are significantly lower than the outside air temperature, it is determined that the outside air temperature sensor Sd has an abnormality. To do. For example, when only the temperature detected by one temperature sensor is significantly lower than the outside air temperature, the temperature sensor individual abnormality determining unit 25 determines that the temperature sensor has an abnormality. In this way, it is possible to individually determine the abnormality of each of the temperature sensors S _aL , S _aR , S _bL , S _bR using an existing temperature sensor or the like. For temperature sensors determined to be abnormal, measures such as not being used for temperature detection can be taken.

The temperature sensor individual abnormality determining means 25 determines whether or not there is an abnormality in each of the left and right motor temperature sensors S _aL and S _aR and the left and right cooling oil temperature sensors S _bL and S _bR while the vehicle is traveling. May be.

According to this configuration, when the torque is commanded so that the left and

right motors

6 and 6 have the same torque while the vehicle is running, the motor temperatures of the left and

right motors

6 and 6 should be approximately the same. If there is a large discrepancy, it is judged as abnormal. In addition, the sensor outputs of the left and right cooling oil temperature sensors S _bL and S _bR should be approximately the same. If there is a large discrepancy, it is judged as abnormal. Regarding the relationship between the temperature detected by the motor temperature sensors S _aL and S _aR and the temperature detected by the cooling oil temperature sensors S _bL and S _bR , the time constant of the temperature of the motor 6 is smaller than the oil temperature, and the motor temperature rises. Is relatively fast. Since the heat source is the motor 6, the motor temperature should always be higher than the cooling oil temperature. In the opposite case, it is determined that one of the sensors is abnormal.

Any combination of at least two configurations disclosed in the claims and / or the specification and / or drawings is included in the present invention. In particular, any combination of two or more of each claim in the claims is included in the present invention.

The present invention will be more clearly understood from the following description of preferred embodiments with reference to the accompanying drawings. However, the embodiments and drawings are for illustration and description only and should not be used to define the scope of the present invention. The scope of the invention is defined by the appended claims. In the accompanying drawings, the same reference numerals in a plurality of drawings indicate the same or corresponding parts.
It is a block diagram of the conceptual composition which shows the electric vehicle carrying the abnormality diagnosis device concerning a 1st embodiment of this invention with a top view. It is sectional drawing of the in-wheel motor drive device in the electric vehicle of FIG. It is the figure which looked at the pump of the oil supply mechanism of the in-wheel motor drive device of FIG. 2 from the axial direction. It is a block diagram which shows the basic structure of the in-wheel motor drive device of FIG. It is a block diagram of the control system of the in-wheel motor drive device of FIG. It is a figure which shows the example of a change of motor temperature and oil temperature. It is a flowchart which shows the process at the time of the initial diagnosis of the abnormality diagnosis apparatus mounted in the electric vehicle of FIG. 1 in steps. It is a flowchart which shows the process in the vehicle driving | running | working of the abnormality diagnosis apparatus mounted in the electric vehicle of FIG. It is a block diagram which shows the modification of the control system of the abnormality diagnosis apparatus mounted in the electric vehicle of FIG. It is a block diagram of the conceptual structure which shows the vehicle provided with the motor drive device which concerns on 2nd Embodiment of this invention with a top view.

A first embodiment of the present invention will be described with reference to FIGS.
<Conceptual configuration of this electric vehicle (vehicle)>
FIG. 1 is a block diagram of a conceptual configuration showing, in plan view, an electric vehicle equipped with an abnormality diagnosis apparatus according to this embodiment. This electric vehicle is a four-wheeled vehicle in which the

wheels

2 and 2 that are the left and right rear wheels of the vehicle body 1 are driving wheels and the

wheels

3 and 3 that are the left and right front wheels are driven wheels. The

front wheels

3 and 3 are steering wheels. The left and

right drive wheels

2, 2 are driven by independent traveling motors 6, respectively. Each motor 6 constitutes an in-wheel motor drive device IWM described later. Each

wheel

2 and 3 is provided with a brake. Further, the

wheels

3 and 3 which are the steering wheels which are the left and right front wheels can be steered via a steering mechanism (not shown) and are steered by a steering means 15 such as a steering wheel.

<About the schematic configuration of the in-wheel motor drive device IWM>
As shown in FIG. 2, each in-wheel motor drive device IWM, which is a left and right motor drive device, has a motor 6, a speed reducer 7, a wheel bearing 4, and an oil supply mechanism Jk (FIG. 3) described later. , Some or all of these are placed in the wheel. The rotation of the motor 6 is transmitted to the wheel 2 which is a drive wheel via the speed reducer 7 and the wheel bearing 4. A brake rotor 5 constituting the brake is fixed to a flange portion of the hub wheel 4 a of the wheel bearing 4, and the brake rotor 5 rotates integrally with the wheel 2. The motor 6 is, for example, an embedded magnet type synchronous motor in which a permanent magnet is built in the core portion of the rotor 6a. This motor 6 is a motor in which a radial gap is provided between a stator 6 b fixed to the housing 8 and a rotor 6 a attached to the rotation output shaft 9.

<About the lubrication mechanism>
As shown in FIGS. 2 and 3, the oil supply mechanism Jk is a so-called shaft center oil supply mechanism that supplies lubricating oil used for cooling the motor 6 and lubricating and cooling the speed reducer 7 from the inside of the rotary output shaft 9. The oil supply mechanism Jk includes a pump 27, a lubricating oil storage unit 10, and a plurality of oil passages 11. The pump 27 and the lubricating oil reservoir 10 are each provided in the housing 8. The pump 27 sucks up the lubricating oil stored in the lubricating oil reservoir 10 from the lubricating oil reservoir 10 and circulates it through the plurality of oil passages 11.

The pump 27 includes an inner rotor 40 that rotates as the output member 12 rotates, an outer rotor 41 that rotates following the rotation of the inner rotor 40, a pump chamber 42, a suction port 43, and a discharge port 44. It is a cycloid pump. The inner rotor 40 is configured to be rotated by the rotation of the output member 12. When the inner rotor 40 is rotated by the rotation of the output member 12 driven by the motor 6, the outer rotor 41 is driven to rotate. At this time, the inner rotor 40 and the outer rotor 41 rotate about different rotation centers c1 and c2, respectively, so that the volume of the pump chamber 42 constantly changes. As a result, the lubricating oil stored in the lubricating oil reservoir 10 is sucked up, flows in from the suction port 43, and is sequentially pumped from the discharge port 44 to the plurality of oil passages 11.

In this electric vehicle, a part of the lubricating oil pumped into the rotation output shaft 9 during rotation of the motor 6 is guided to the motor 6 by the centrifugal force of the rotor 6 a and the pressure of the pump 27. The motor 6 is cooled. The lubricating oil used for this cooling moves downward due to gravity and collects in the lower part of the housing 8, and is then stored in the lubricating oil storage part 10 communicating with the lower part of the housing 8. The remaining lubricating oil that has not been used for cooling the motor 6 is guided into the speed reducer 7 by the centrifugal force and the pressure of the pump 27, and lubricates and cools each part in the speed reducer 7. The lubricating oil provided for this lubrication or the like moves downward due to gravity and is stored in the lubricating oil reservoir 10 via an oil discharge port (not shown).

<About sensors>
As shown in FIG. 4, the in-wheel motor drive device IWM that drives the left wheel 2 is provided with a left motor temperature sensor S _aL and a left cooling oil temperature sensor S _bL to drive the right wheel 2. The in-wheel motor drive device IWM that is provided is provided with a right motor temperature sensor _SaR and a right cooling oil temperature sensor _SbR . A total of four temperature sensors are provided for the left and right in-wheel motor drive devices IWM. Each temperature sensor is provided to monitor the temperature of the motor 6.

As these motor temperature sensors S _aL , S _aR and cooling oil temperature sensors S _bL , S _bR , for example, a thermistor that detects a temperature change in resistance with a voltage value when a certain current flows is used. Each motor temperature sensor S _aL , S _aR is provided, for example, in a housing 8 (FIG. 2) of each motor 6 or a gap between motor coils adjacent to each other in the circumferential direction. Each cooling oil temperature sensor _SbL , _SbR is provided in each lubricating oil storage part 10 (FIG. 2), for example, and detects the temperature of the cooling oil which cools the reduction gear 7 and the motor 6. FIG. The temperatures detected by the four sensors are taken into the left and right inverter devices 13 or ECUs 14 and the temperature rise of each motor 6 is monitored.

The electric vehicle is further provided with a temperature sensor Sd for detecting the outside temperature of the electric vehicle. The temperature detected by the air temperature sensor Sd is taken into the left and right inverter devices 13 or the ECU 14 and used during initial diagnosis described later. As the temperature sensor Sd, a dedicated product for the abnormality diagnosis device may be used. Instead, the coolant temperature, various ECU temperatures, the inverter IGBT temperature, the intake air temperature, the air conditioner temperature, and the like may be used as the outside air temperature. However, when the cooling water temperature, various ECU temperatures, inverter IGBT temperature, intake air temperature, air conditioner temperature, etc. are used for the initial diagnosis described later, the difference from the atmospheric temperature is taken into consideration during the evaluation.

<About control system>
FIG. 5 is a block diagram of a control system of the in-wheel motor drive device IWM. As shown in FIGS. 1 and 5, the control device includes an ECU 14 that is an electric control unit that controls the entire vehicle, and

inverter devices

13 and 13 that control the left and right motors 6 for traveling in accordance with commands from the ECU 14. Have In the case of an electric vehicle, the ECU 14 is an electric control unit (VCU) that controls the entire vehicle. As shown in FIG. 5, each inverter device 13 includes a power circuit unit 16 for the corresponding motor 6 and a motor control unit 17 that controls the power circuit unit 16. The motor control unit 17 has a function of outputting each information stored in the motor control unit 17 to the ECU 14 such as each detection value and control value regarding the in-wheel motor drive device IWM.

The power circuit unit 16 includes an inverter 16a that converts the DC power of the battery 18 into three-phase AC power used to drive the motor 6, and a PWM driver 16b that controls the inverter 16a. The inverter 16a is composed of a plurality of semiconductor switching elements (not shown). The PWM driver 16b performs pulse width modulation on the input current command and gives an on / off command to each of the semiconductor switching elements.

The motor control unit 17 includes a computer, a program executed on the computer, and an electronic circuit, and includes a motor drive control unit 19 as a basic control unit. The ECU 14 receives an accelerator opening signal (acceleration command) output from the accelerator operation unit 20 (FIG. 1) and a deceleration command output from the brake operation unit 21 (FIG. 1), or an acceleration command, a deceleration command, and steering means. Acceleration / deceleration commands to be given to the

motors

6 and 6 of the left and right rear wheels 2 and 2 (FIG. 1) are generated as torque commands from the turning command output by 15 (FIG. 1) and output to each inverter device 13.

The motor drive control unit 19 is a unit that converts an acceleration / deceleration command based on a torque command or the like given from the ECU 14, which is a higher-level control unit, into a current command and gives a current command to the PWM driver 16b. The motor drive control unit 19 obtains a motor current flowing from the inverter 16a to the motor 6 from the current detection means Se, and performs current feedback control. Further, the motor drive control unit 19 obtains the rotation angle of the rotor 6a (FIG. 2) of the motor 6 from the rotation speed detection sensor Sc and performs vector control.

In this embodiment, the ECU 14 is provided with an abnormality diagnosis device 22 for diagnosing abnormalities in the temperature sensors S _aL , S _aR , S _bL , S _bR and the temperature sensor Sd. The abnormality diagnosis device 22 includes a temperature comparison unit 23, an outside air temperature comparison unit 24, and a temperature sensor individual abnormality determination unit 25. The temperature comparison means 23 determines the two motor temperatures detected by the left and right motor temperature sensors S _aL and S _aR and the two cooling oil temperatures detected by the left and right cooling oil temperature sensors S _bL and S _bR. The two given temperatures are compared with each other. The outside air temperature comparing means 24 compares the temperatures of the motors 6 and the cooling oils with the outside air temperature detected by the air temperature sensor Sd. The temperature sensor individual abnormality determining unit 25 compares the result of comparison by the temperature comparing unit 23 and the outside air temperature comparing unit 24 or the average value comparing unit 26 (when there is no temperature sensor, as shown in FIG. Based on the comparison result obtained by comparing the paired average value comparison means 26 in place of the means 24, the presence or absence of abnormality of each temperature sensor S _aL , S _aR , S _bL , S _bR is individually determined. Further, the temperature sensor individual abnormality determining means 25, when it is determined that any one of the temperature sensors is abnormal, for example, the temperature sensor S _aL , S _aR , S _bL or the display device 28 provided on the console panel of the vehicle. Command to output a display notifying the abnormality of _SbR .

FIG. 6 is a diagram showing an example of changes in motor temperature and oil temperature in one in-wheel motor drive device. While the vehicle is traveling (I in FIG. 6), both the motor temperature and the oil temperature fluctuate up and down due to motor loss. During traveling, the motor temperature is usually higher than the oil temperature. During parking (stopped state with the vehicle powered off) (II in FIG. 6), the motor temperature and the oil temperature are lowered by the outside air temperature. Then, after the motor temperature and the oil temperature are lowered due to parking, the vehicle travels again (III in FIG. 6). Next, when the vehicle is stopped for a short time (IV in FIG. 6), the next vehicle starts to travel. At the time (V in FIG. 6), the motor temperature and the oil temperature are still high without decreasing to the outside air temperature.

FIG. 7 is a flowchart showing in steps the process at the time of initial diagnosis of the abnormality diagnosis apparatus. The initial diagnosis when the vehicle has the temperature sensor Sd will be described with reference to FIG. 5 and Table 1. In Table 1, Tat temperature of temperature sensor Sd, the temperature Trm is detected by the right motor temperature sensor _{S aR,} temperature Tro is detected by the right of the cooling oil temperature sensor _{S bR,} Tlm the left motor temperature sensor temperature detected by the S _aL, Tlo indicates the temperature detected by the left of the cooling oil temperature sensor _{S bL.} In Table 1, “≈” indicates that the temperatures are approximately the same. For example, it is assumed that the temperature difference is within ± 5 ° C. In Table 1, the case where “>>” and “<<” temperature differences are significantly large is shown. “Remarkably” means, for example, a case where the temperature difference is 10 ° C. or more. The same applies to Tables 2 and 3 described later. Further, α and β in Table 1 are variables having positive values, and are functions such as a vehicle stop time, a stop-time temperature, and an outside air temperature.

The initial diagnosis by the abnormality diagnosis device 22 is started within a certain period of time before the vehicle travels from when the vehicle is turned on, and the abnormality diagnosis device 22 determines that there is the temperature sensor Sd (Yes in step a1). Then, it is determined whether or not the condition 1 is satisfied by the outside air temperature comparison means 24 (step a2). The predetermined time is a time determined as appropriate according to design or the like, and is a short time of about 300 milliseconds, for example. If the vehicle does not originally include the temperature sensor Sd, the step a1 for determining the presence or absence of the temperature sensor Sd and steps a4, a6 to a8 are omitted, and the process proceeds from step a9 after the start of this process. Good.

Satisfying condition 1 (Yes in step a2) is a case where all of Trm≈Tat, Tro≈Tat, Tlm≈Tat, and Tlo≈Tat are satisfied. This is a case where the temperature (sensor output) is about the same as the air temperature.

If it is determined that the condition 1 is not satisfied (No in step a2), it is determined whether or not the condition 2 is satisfied by the outside air temperature comparison means 24 (step a3).
Satisfying condition 2 (Yes in step a3) is a case where all of Trm >> Tat, Tro >> Tat, Tlm >> Tat, Tlo >> Tat are satisfied. Is when it is warm.

If it is determined that the condition 2 is not satisfied (No in step a3), it is determined whether or not the condition 3 is satisfied by the outside air temperature comparison means 24 (step a4).

Satisfying condition 3 is a case where all of Trm≈Tat + α, Tro≈Tat + α, Tlm≈Tat + β, and Tlo≈Tat + β are satisfied, and either one of the left and right wheels is warmed by sunlight or the like, or This is a case where one of the wheels is rapidly cooled by water or snow. When at least one of the conditions 1 to 3 is satisfied, no obvious abnormality is recognized in each temperature sensor. Therefore, the temperature sensor individual abnormality determining unit 25 determines that all the temperature sensors are normal (step a5). After this step a5, the initial diagnosis ends normally. Also, if condition 2 is determined after the time has passed since the time when condition 1 was determined immediately after stopping, and condition 2 is determined, it may not apply to either condition. Intermediate conditions can also be added.

If it is determined that the condition 3 is not satisfied (No in step a4), it is determined whether or not the condition 4 is satisfied by the outside air temperature comparison means 24 (step a6).

Satisfying condition 4 (Yes in step a6) is a case where all of Trm << Tat, Tro << Tat, Tlm << Tat, and Tlo << Tat are satisfied. When this condition 4 is satisfied (Yes in step a6), the temperature sensor individual abnormality determining unit 25 determines that the temperature sensor Sd is abnormal. This is because the temperature of the temperature sensor Sd does not become much lower than the temperatures of the temperature sensors S _aL , S _aR , S _bL , S _bR . Therefore, the temperature sensor individual abnormality determining unit 25 operates by assuming that the temperature sensor Sd is not present, without using the temperature sensor Sd (step a7). After step a7, the process proceeds to the initial diagnosis (conditions 9 to 15) when there is no temperature sensor Sd. These conditions 9 to 15 will be described later.

When the condition 4 is not satisfied (No in step a6), it is determined by the outside air temperature comparison means 24 whether each of the conditions 5 to 8 is satisfied (step a8).

Conditions 5 to 8 are that the temperature output by the three temperature sensors among the four sensor outputs of the left and right motor temperature sensors S _aL and S _aR and the left and right cooling oil temperature sensors S _bL and S _bR is the temperature sensor Sd. The condition is that the temperature is approximately the same as the sensor output, and the temperature output by the remaining one temperature sensor is significantly lower than the temperature output by the air temperature sensor Sd.

In this case, the temperature sensor individual abnormality determining unit 25 determines that the temperature sensor that has detected a temperature significantly lower than the sensor output of the temperature sensor Sd is abnormal (step a10). Thereafter, it is possible to take measures such as not using the sensor output of the temperature sensor in the control of the motor 6 (that is, control by the motor drive control unit 19). After step a10, the initial diagnosis is terminated. Although not shown in FIG. 7 and Table 1, among the four temperature sensors S _aL , S _aR , S _bL , S _bR , three sensor outputs are significantly larger than the sensor output of the temperature sensor Sd, and the remaining Even when one sensor output is significantly smaller than the sensor output of the temperature sensor Sd, a temperature sensor that outputs a temperature significantly smaller than the sensor output of the temperature sensor Sd can be determined to be abnormal as in the case described above.

As shown in FIG. 9, at the time of the initial diagnosis when there is no temperature sensor, the temperature sensor individual abnormality determination unit 25 compares the result compared by the temperature comparison unit 23 and the result compared by the paired average value comparison unit 26. _Therefore , the presence or absence of abnormality of each temperature sensor S _aL , S _aR , S _bL , S _bR is individually determined according to the conditions in Table 2. The paired average value comparison means 26 is configured to detect the temperature of each motor 6 detected by the left and right motor temperature sensors S _aL and S _aR and the temperature of each cooling oil detected by the left and right cooling oil temperature sensors S _bL and S _bR . Each temperature and the average value of all temperatures are compared with each other.

7 and 9 and Table 2 will be used to explain the initial diagnosis when the vehicle has no temperature sensor (including the case where the vehicle is regarded as having no temperature sensor). In Table 2, Tav is an average value of sensor outputs of four temperature sensors S _aL , S _aR , S _bL , S _bR , and is obtained by Tav = (Trm + Tro + Tlm + Tlo) / 4 by the average value comparison means 26 (described later). The same applies to Table 3). In other words, Tav is an average value of temperatures output from the four temperature sensors S _aL , S _aR , S _bL , and S _bR . In this initial diagnosis, first, the paired average value comparing means 26 determines whether or not the condition 9 is satisfied (step a9).

Satisfying condition 9 is the case where all of Trm≈Tav, Tro≈Tav, Tlm≈Tav, and Tlo≈Tav are satisfied. Sufficient time has passed since the vehicle stopped, and the temperature output by all temperature sensors (sensor output) Is the same level. When the condition 9 is satisfied (Yes in step a9), the process proceeds to step a5 and all temperature sensors are determined to be normal. If it is determined that the condition 9 is not satisfied (No in step a9), the temperature comparison unit 23 determines whether or not the condition 10 is satisfied (step a11).

The condition 10 is satisfied when Trm≈Tlm and Tro≈Tlo are satisfied. This is because the motor 6 and the oil temperature are warmed immediately after the vehicle stops, and even if there is a temperature difference between the motor temperature and the oil temperature, the left and right motor temperatures and the left and right oil temperatures are approximately the same. This is the case. When the condition 10 is satisfied (Yes in step a11), the process proceeds to step a5 and all temperature sensors are determined to be normal. If it is determined that the condition 10 is not satisfied (No in step a11), the temperature comparison unit 23 determines whether the condition 11 is satisfied (step a12).

Satisfying condition 11 is a case where Trm≈Tro and Tlm≈Tlo are satisfied, and either of the left and right wheels is warmed by sunlight or the like, or one of the wheels is This is the case where the water is cooled rapidly with water, snow, or the like, and the right motor temperature and the right oil temperature, and the left motor temperature and the left oil temperature are approximately the same. When the condition 11 is satisfied (Yes in step a12), the process proceeds to step a5 and all the temperature sensors are determined to be normal. When it is determined that the condition 11 is not satisfied (No in step a12), it is determined whether or not each of the conditions 12 to 15 is satisfied by the paired average value comparison means 26 (step a13).

Conditions 12 to 15 are conditions in which only the temperature output by the remaining one temperature sensor is extremely lower than the temperatures output by three of the four temperature sensors. In this case, the temperature sensor individual abnormality determining unit 25 determines that the temperature sensor that outputs a temperature extremely lower than the temperatures output by the other three sensors is abnormal (step a10). Thereafter, it is possible to take measures such as not using the sensor output of the temperature sensor in the control of the motor 6 (that is, control by the motor drive control unit 19). In addition, if an abnormality occurs in the above diagnosis, considering a malfunction of detection, etc., it was determined that the abnormality was only performed when it was tested not only once but several times in succession and was judged abnormal all times. It is also possible to shift to processing such as not using a sensor.

As shown in FIG. 9, while the vehicle is running, the temperature sensor individual abnormality determination unit 25 determines whether each temperature sensor is based on the result of comparison by the temperature comparison unit 23 and the result of comparison by the paired average value comparison unit 26. The presence or absence of abnormality in S _aL , S _aR , S _bL , and S _bR is individually determined according to the conditions in Table 3. The abnormality diagnosis device 22 can determine, for example, whether or not the vehicle is traveling from one or both of the motor current obtained from the current detection means Se and the motor rotation angle obtained from the rotation speed detection sensor Sc.

8 and 9 and Table 3 are used to explain the diagnosis while the vehicle is running. In the diagnosis during traveling of the vehicle, the average value comparison means 26 first determines whether or not the condition 16 is satisfied (step b1). The condition 16 is satisfied when Trm≈Tav, Tro≈Tav, Tlm≈Tav, and Tlo≈Tav are all satisfied, and when the temperature of all the temperature sensors is approximately the same. When the condition 16 is satisfied (Yes in step b1), the process proceeds to step b2, and all the temperature sensors are determined to be normal. Thereafter, the diagnosis result is normal and the process is terminated.

If it is determined that the condition 16 is not satisfied (No in step b1), the temperature comparison unit 23 determines whether the condition 17 is satisfied (step b3). The condition 17 is satisfied when Trm≈Tlm and Tro≈Tlo are satisfied. This is a case where the left and right motor temperatures and the left and right oil temperatures are approximately the same even if there is a temperature difference between the motor temperature and the oil temperature. When the condition 17 is satisfied (Yes in step b3), the process proceeds to step b2, and all the temperature sensors are determined to be normal.

If it is determined that the condition 17 is not satisfied (No in step b3), it is determined whether or not the condition 18 is satisfied by the temperature comparison unit 23 (step b4). Satisfying condition 18 is a case where Trm≈Tro and Tlm≈Tlo are satisfied, and the right motor temperature and the right oil temperature, and the left motor temperature and the left oil temperature are approximately the same. Is the case. When the condition 18 is satisfied (Yes in step b4), the process proceeds to step b2, and all the temperature sensors are determined to be normal. If it is determined that the condition 18 is not satisfied (No in step b4), the temperature comparison unit 23 determines whether or not the condition 19 is satisfied (step b5).

The condition 19 is satisfied when Trm << Tro is satisfied, and when the right motor temperature is significantly lower than the right oil temperature. In this case, for example, after a certain time (step b6), it is determined again whether the condition 19 is satisfied (step b7). If the condition 19 is satisfied again (Yes in step b7), the right motor It is determined that the temperature sensor S _aR or the right cooling oil temperature sensor S _bR is abnormal (step b8). Thereafter, the diagnosis result is abnormal and the present process is terminated.

When the condition 19 is not satisfied (No in step b5, No in step b7), the temperature comparison unit 23 determines whether the condition 20 is satisfied (step b9). Satisfying the condition 20 is a case where Tlm << Tlo is satisfied, and a case where the left motor temperature is significantly lower than the left oil temperature. In this case, for example, after a predetermined time (step b10), it is determined whether or not the condition 20 is satisfied again (step b11). If the condition 20 is satisfied again (Yes in step b11), the left motor temperature sensor _{S aL} or left cooling oil temperature sensor _{S bL} is judged to be abnormal (step b12).

If the condition 20 is not satisfied (No in Step b9, No in Step b11), the paired average value comparing means 26 determines whether or not each of the conditions 21 to 24 is satisfied (Step b13). Conditions 21 to 24 are conditions in which only the temperature output from the remaining one temperature sensor is extremely lower than the temperatures output from three of the four temperature sensors. In this case (Yes in step b13), the temperature sensor individual abnormality determining unit 25 determines that the temperature sensor that outputs an extremely low temperature is abnormal (step b14). Thereafter, the sensor output of the temperature sensor is not used in the control of the motor 6 (ie, control by the motor drive control unit 19). If all the conditions 21 to 24 are not satisfied (No in step b13), the process proceeds to step b2 and all the temperature sensors are determined to be normal.

These tests are performed at regular intervals while the vehicle is running, for example, every 10 seconds. In addition, in consideration of malfunction of detection, the judgment of abnormality may be shifted to processing such as not using the temperature sensor detected as abnormal, only when it is judged that the abnormality is not continuous once but several times continuously. it can.

Further, in the process of FIG. 8, even when it is determined that there is no abnormal temperature sensor in the initial diagnosis (all temperature sensors are determined to be normal), there is a temperature sensor that is abnormal in the initial diagnosis. Separately, processing that takes that into consideration.

<About the effects>
According to the abnormality diagnosing device 22 described above, the existing left and right motor temperature sensors S _aL and S _aR , the left and right cooling oil temperature sensors S _bL and S _bR, and the temperature sensor according to predetermined conditions at the time of initial diagnosis. When Sd is present, the temperature sensor Sd can be used to individually determine abnormality of each temperature sensor S _aL , S _aR , S _bL , S _bR . The temperature sensor determined to be abnormal is not used for temperature detection thereafter, and the temperature of the motor 6 can be monitored using only a normal temperature sensor.

Even during vehicle running, according a defined condition, the left and right motor temperature sensor _S _aL, and _{S aR,} left and right cooling oil temperature sensor _S _bL, by using the _{S bR,} the temperature sensor _S _{aL, S} aR, S Abnormalities in _bL and _SbR can be determined individually. The temperature sensor determined to be abnormal is not used for temperature detection thereafter, and the temperature of the motor 6 can be monitored using only a normal temperature sensor.

When the motor temperature is monitored using only a normal temperature sensor while the vehicle is running, for example, when the motor temperature exceeds a threshold value, the control device reduces the current of each motor 6 so as to reduce the current. The motor drive control unit 19 instructs the power circuit unit 16. In this case, the motor current may be reduced at a predetermined ratio with respect to the current motor current, or a predetermined value may be decreased. Thereby, the overload of the motor 6 can be prevented. When the motor temperature becomes equal to or lower than the threshold value after a certain time, the control device releases the restriction on the output to each motor 6. The threshold value is determined by a test or simulation.

<About the second embodiment>
In the following description, the same reference numerals are given to portions corresponding to the matters described in advance in the respective embodiments, and overlapping descriptions are omitted. When only a part of the configuration is described, the other parts of the configuration are the same as those described in advance unless otherwise specified. The same effect is obtained from the same configuration. Not only the combination of the parts specifically described in each embodiment, but also the embodiments can be partially combined as long as the combination does not hinder.

In the in-wheel motor drive device, a cycloid reducer, a planetary reducer, a two-axis parallel reducer, and other reducers can be applied. Further, in the in-wheel motor drive device of the above-described embodiment, the rear wheel drive is shown, but the front wheel drive or the four wheel drive may be used. In the above embodiment, the example in which the drive control device is applied to the electric vehicle equipped with the in-wheel motor drive device has been described. However, as shown in FIG. A two-motor on-board type electric vehicle in which the

speed reducers

7 and 7 corresponding to 6 are provided and the left and

right wheels

3 and 3 are driven by the

motors

6 and 6 may be provided with an abnormality diagnosis device. In FIG. 10, the left and right wheels driven by the motor 6 may be either the front or

rear wheels

3 and 2. Also, four-wheel drive may be used.

As described above, the preferred embodiments have been described with reference to the drawings, but various additions, changes, or deletions can be made without departing from the spirit of the present invention. Therefore, such a thing is also included in the scope of the present invention.

2, 3 ... Wheel 6 ... Motor 22 ... Abnormality diagnosis device 23 ... Temperature comparison means 24 ... External air temperature comparison means 25 ... Temperature sensor individual abnormality determination means 26 ... Mean value comparison means S _aL , S _aR ... Left and right motor temperature sensors S _bL , S _bR ... Left and right cooling oil temperature sensor Sd ... Air temperature sensor

Claims

An abnormality in the left and right motor temperature sensors for detecting the temperatures of the respective motors of the left and right motor drive devices in a vehicle having left and right motor drive devices for independently driving the left and right wheels; and the left and right motor drive devices An abnormality diagnosing device for diagnosing abnormalities in the left and right cooling oil temperature sensors that detect the temperature of each cooling oil to be cooled at an initial diagnosis that is within a certain period of time before the vehicle travels from when the vehicle is turned on. And
A temperature comparing means for comparing two motor temperatures detected by the left and right motor temperature sensors and two cooling oil temperatures detected by the left and right cooling oil temperature sensors;
The temperatures of the two motors detected by the left and right motor temperature sensors, the two cooling oil temperatures detected by the left and right cooling oil temperature sensors, the left and right motor temperature sensors and the left and right cooling oils An average value comparison means for comparing the average value of the temperature detected by the temperature sensor;
Temperature sensor individual abnormality determination for determining whether there is an abnormality in each of the left and right motor temperature sensors and the left and right cooling oil temperature sensors from the comparison result by the temperature comparison means and the comparison result by the paired average value comparison means And an abnormality diagnosis device.
An abnormality in the left and right motor temperature sensors for detecting the temperatures of the respective motors of the left and right motor drive devices in a vehicle having left and right motor drive devices for independently driving the left and right wheels; and the left and right motor drive devices An abnormality diagnosing device for diagnosing abnormalities in the left and right cooling oil temperature sensors that detect the temperature of each cooling oil to be cooled at an initial diagnosis that is within a certain period of time before the vehicle travels from when the vehicle is turned on. And
The vehicle includes an air temperature sensor that detects an outside air temperature of the vehicle,
Of the two motor temperatures detected by the left and right motor temperature sensors and the two cooling oil temperatures detected by the left and right cooling oil temperature sensors, two predetermined temperatures are compared with each other according to a predetermined condition. Temperature comparison means;
Each of the two motor temperatures detected by the left and right motor temperature sensors, the two cooling oil temperatures detected by the left and right cooling oil temperature sensors, and the outside air temperature detected by the air temperature sensor An outside temperature comparison means for comparing
Temperature sensor individual abnormality determination means for determining whether each of the left and right motor temperature sensors and the left and right cooling oil temperature sensors has an abnormality based on the comparison result by the temperature comparison means and the comparison result by the outside air temperature comparison means. And an abnormality diagnosis device.
3. The abnormality diagnosis device according to claim 1, wherein the temperature sensor individual abnormality determination unit detects an abnormality of each of the left and right motor temperature sensors and the left and right cooling oil temperature sensors while the vehicle is running. An abnormality diagnosis device that determines the presence or absence.