On-board devices and communication systems

Abstract

The present invention enables high-precision detection of component abnormalities. The in-vehicle device of the present invention is mounted in a vehicle and communicates with a server, comprising: a first information generating unit that uses output from a sensor mounted in the vehicle to generate first information related to the status of a first component mounted in the vehicle; and an off-vehicle communication unit that transmits the first information and second information related to the status of a second component different from the first component to the server, and receives from the server a status signal indicating an abnormal status of the first component, calculated by the server based on the first and second information.

Description

Technical Field

[0001] The present invention relates to a vehicle-mounted device and a communication system. Background Art

[0002] To achieve safe and secure vehicle travel, technology for detecting component anomalies is required. Patent Document 1 discloses a construction machinery management system that manages the status of each machine in a group of construction machinery. The group of construction machinery includes at least one first machine and at least one second machine. The first machine has a first information detection device for detecting first information related to the construction machinery and a second information detection device for detecting second information. The second machine has the first information detection device but does not have the second information detection device. The construction machinery management system is characterized by including a machine state diagnostic device that performs a premonition diagnosis of a fault state related to the second information of the second machine based on information related to the first and second information obtained from the first machine and the first information of the second machine.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2016-109019 Summary of the Invention

[0006] Problems to be solved by the invention

[0007] In the invention described in Patent Document 1, there is room for improvement in the accuracy of component abnormality detection.

[0008] Technical means to solve the problem

[0009] The first form of the vehicle-mounted device of the present invention is a vehicle-mounted device that is installed in a vehicle and communicates with a server, and comprises: a first information generating unit, which uses the output of a sensor installed in the vehicle to generate first information related to the status of a first component installed in the vehicle; and an off-vehicle communication unit, which sends the first information and second information related to the status of a component different from the first component, namely, a second component, to the server, and receives from the server a status signal indicating an abnormal status of the first component calculated by the server based on the first information and the second information.

[0010] A second form of a communication system of the present invention is a communication system comprising a server capable of communicating with each other and a vehicle-mounted device mounted in a vehicle, the vehicle-mounted device comprising: a first information generating unit, which uses the output of a sensor mounted in the vehicle to generate first information related to the state of a first component mounted in the vehicle; and an off-vehicle communication unit, which sends the first information and second information related to the state of a component different from the first component, namely, a second component, to the server, the server comprising: a fatigue evaluation unit, which calculates a status signal indicating an abnormal state of the first component based on the first information and the second information; and a server communication unit, which sends the status signal to the vehicle-mounted device, and the off-vehicle communication unit of the vehicle-mounted device receives the status signal.

[0011] The third form of the vehicle-mounted device of the present invention is a vehicle-mounted device installed in a vehicle, comprising: a first information generating unit, which uses the output of a sensor installed in the vehicle to generate information related to the state of a first component installed in the vehicle, namely, first information; and a vehicle-mounted storage unit, which stores an accumulated value of fatigue of the first component, wherein the vehicle-mounted storage unit further stores fatigue limit information, and the fatigue limit information can use the first information and information related to the state of a component different from the first component, namely, a second component, namely, second information to calculate the increase in fatigue of the first component, and the vehicle-mounted device further comprises a fatigue evaluation unit, wherein the fatigue evaluation unit uses the first information, the second information and the fatigue limit information to calculate the increase in fatigue, and when the sum of the accumulated value of fatigue stored in the vehicle-mounted storage unit and the increase in fatigue exceeds a specified threshold value, it is judged that the first component is in an abnormal state.

[0012] Effects of the Invention

[0013] According to the present invention, abnormality of a component can be detected with high accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a diagram showing the overall configuration of the operation system in the first embodiment.

[0015] Figure 2 This is a diagram of the vehicle's mechanical structure.

[0016] Figure 3 This is a diagram of the vehicle's electrical structure.

[0017] Figure 4 This is a conceptual diagram showing the time-series changes in the accelerometer output and reaction torque.

[0018] Figure 5 This is a diagram showing an example of stress information.

[0019] Figure 6 A conceptual diagram of fatigue limit information.

[0020] Figure 7 A diagram showing an example of a vehicle database.

[0021] Figure 8 This is a flowchart showing the operation of the vehicle-mounted device.

[0022] Figure 9 This is a flowchart showing the operation of the server.

[0023] Figure 10 The voltage V in the third modification is shown in FIG. UN and voltage V U'N An example of a voltage pulse waveform.

[0024] Figure 11 This is a diagram showing an example of insulation information in Modification 3.

[0025] Figure 12 This is a conceptual diagram of the threshold value change process of the fatigue evaluation unit 23 in the fourth modification.

[0026] Figure 13 This is a diagram showing the configuration of the vehicle-mounted device in the second embodiment. DETAILED DESCRIPTION

[0027] -First embodiment-

[0028] Below, reference Figures 1 to 7 A first embodiment of the calculation system will be described. In this embodiment, the object is the advance detection of fatigue failure using the linear cumulative damage law.

[0029] (constitute)

[0030] Figure 1 is a diagram showing the overall structure of a computing system S. The computing system S includes an in-vehicle device 10 and a server 20 . Figure 1 , only one vehicle-mounted device 10 is described, but the computing system S may include multiple vehicle-mounted devices 10. The vehicle-mounted device 10 is mounted on the vehicle 9. In order to distinguish the vehicle 9 equipped with the vehicle-mounted device 10 from other vehicles, it may be referred to as the "own vehicle" 9.

[0031] The in-vehicle device 10 is, for example, an electronic control unit (ECU) and includes a first information generating unit 11 , a second information generating unit 12 , an in-vehicle communication unit 13 , an out-of-vehicle communication unit 14 , a vehicle control unit 15 , and a notification unit 16 .

[0032] The first information generating unit 11 generates the first information described later. The second information generating unit 12 generates the second information described later. The in-vehicle communication unit 13 communicates with other devices such as sensors installed in the vehicle 9. The in-vehicle communication unit 13 is, for example, a communication interface that supports communication standards such as IEEE802.3. The out-vehicle communication unit 14 communicates with devices outside the vehicle 9 such as a server 20. The out-vehicle communication unit 14 is, for example, a wireless communication module that supports 4G or 5G. Among them, the out-vehicle communication unit 14 can communicate directly with the server 20, or can communicate with the server 20 by relaying on one or more devices.

[0033] The vehicle control unit 15 automatically controls the vehicle 9. The onboard device 10 includes a non-volatile onboard storage unit (not shown). The vehicle control unit 15 controls the vehicle 9 by referring to a high-precision map stored in the onboard storage unit. The vehicle 9 can be controlled not only automatically by the vehicle control unit 15 but also by the occupants of the vehicle 9. The notification unit 16 is, for example, a speaker or liquid crystal display. The notification unit 16 notifies the occupants of the vehicle 9 of any problems with components of the vehicle 9.

[0034] The first information generating unit 11, the second information generating unit 12, and the vehicle control unit 15 are implemented by a CPU (not shown) included in the vehicle-mounted device 10, which expands a program stored in a ROM (not shown) into RAM and executes the program. However, the first information generating unit 11, the second information generating unit 12, and the vehicle control unit 15 can also be implemented by an FPGA (Field Programmable Gate Array), which is a rewritable logic circuit, or an ASIC (Application Specific Integrated Circuit), which is an integrated circuit for a specific application.

[0035] The server 20 is a computer composed of one or more computers and includes a stress calculation unit 21 , a frequency calculation unit 22 , a fatigue evaluation unit 23 , a server communication unit 24 , and a server storage unit 30 .

[0036] The stress calculation unit 21 generates stress information 34, described below, and stores it in the server storage unit 30. The frequency calculation unit 22 generates fatigue limit information 35, described below, and stores it in the server storage unit 30. The fatigue evaluation unit 23 evaluates component fatigue using the first and second information received from the vehicle-mounted device. The stress calculation unit 21, frequency calculation unit 22, and fatigue evaluation unit 23 are implemented by a CPU (not shown) equipped in the server 20, which expands programs stored in a ROM (not shown) into RAM and executes them. However, the stress calculation unit 21, frequency calculation unit 22, and fatigue evaluation unit 23 can also be implemented using a rewritable logic circuit, such as an FPGA or ASIC.

[0037] The server storage unit 30 is a nonvolatile storage device such as a hard disk drive. The server storage unit 30 stores component information 31, physical property values ​​32, a vehicle database 33, stress information 34, and fatigue limit information 35. The information stored in the server storage unit 30 will be described later.

[0038] Figure 2 FIG. 1 is a diagram showing the mechanical structure of vehicle 9. Figure 3 This is a diagram of the electrical configuration of vehicle 9. Vehicle 9 includes a battery 910, a DC power cable 911, an inverter 920, an AC power cable 925, a motor 930, a transmission 940, a drive shaft 906, a brake device 907, wheels 908, a first accelerometer 951, a second accelerometer 952, and a third accelerometer 953. Wheels 908 are composed of wheels 908a through 908d, and brake device 907 is composed of brake devices 907a through 907d.

[0039] The battery 910 supplies power to the inverter 920 via a DC power cable 911. The inverter 920 comprises a smoothing capacitor 921 for smoothing the DC voltage applied by the battery 910 and a bridge circuit for each phase. The power module 922 comprises two IGBTs (Insulated Gate Bipolar Transistors) 923, each of which functions as a switching element for the upper and lower arms, and a diode 924 connected in parallel to each IGBT 923. The power module 922 performs a switching operation, converts the DC power supplied from the battery 910 into AC power, and outputs the AC power to the motor 930 via an AC power cable 925. The motor 930 consumes electricity to generate rotational energy, which is then transmitted to the gearbox 940 and the drive shaft 906 to rotate the wheels 908. In addition, a brake device 907 is mounted on the top end of the drive shaft 906 connected to the wheels 908.

[0040] The motor 930 is fixed to the vehicle 9 at multiple locations. In this embodiment, it is fixed to the vehicle 9 at three locations. A first accelerometer 951, a second accelerometer 952, and a third accelerometer 953 are respectively provided at the fixed locations. Hereinafter, the first accelerometer 951, the second accelerometer 952, and the third accelerometer 953 are also collectively referred to as accelerometers 950. The accelerometer 950 outputs acceleration for each of the XYZ axes with respect to the vehicle 9. Regarding the speed of the vehicle 9, the rotation speed of the wheel speed sensors mounted on the brake devices 907a to 907d connected to the transmission shaft 906 is detected, and the rotation speed of the wheel speed sensors mounted on the brake devices 907a to 907d is multiplied by a predetermined coefficient to calculate the speed of the vehicle 9.

[0041] Figure 4 A conceptual diagram showing the time-series changes in the accelerometer output and reaction torque. Figure 4 In the four graphs shown, the horizontal axis represents time, the top three vertical axes represent the accelerations of the respective axes of first accelerometer 951, and the bottom vertical axis represents the reaction torque input to transmission shaft 906. More specifically, the three vertical axes, from the top, represent, in order, the acceleration fx11 of first accelerometer 951 in the X-axis direction, the acceleration fy11 of first accelerometer 951 in the Y-axis direction, and the acceleration fz11 of first accelerometer 951 in the Z-axis direction.

[0042] (Evaluation of fatigue failure)

[0043] The energy received by motor 930 from the vehicle body is calculated using the output of accelerometer 950, and the energy received by motor 930 via transmission shaft 906 is indirectly calculated using vehicle information. Specifically, the energy received by motor 930 via transmission shaft 906 can be calculated based on the force acting on the moving vehicle 9 using information such as the weight of the vehicle 9, the frontal projection area, the air resistance coefficient, the total reduction ratio of the speed reducer, the rigidity of the transmission shaft, and the radius of the wheels, as well as the following equations (1) to (13). The rotational speed of transmission shaft 906 of motor 930, the radius of the wheels equipped on vehicle 9, and the driving speed of vehicle 9 are variable values, and other values ​​are stored in a ROM (not shown).

[0044] Furthermore, the value of the rotation angle sensor installed on the transmission shaft 906 of the motor 930 and the value obtained by converting the rotation speed of the wheel speed sensor installed on the braking device 907a~907d can be used to calculate the reaction torque exerted on the transmission shaft 906 of the motor 930 due to the torsion of the transmission shaft 906 based on the obtained phase difference.

[0045] [Formula 1]

[0046] F V =F W +F B +R t ...Equation 1

[0047] [Formula 2]

[0048] R t =R a +R r +R e +R c ...Equation 2

[0049] [Formula 3]

[0050]

[0051] [Formula 4]

[0052] R r=μ*M V *g*cosθ…Equation 4

[0053] [Formula 5]

[0054] R e =M V *g*sinθ…Equation 5

[0055] [Formula 6]

[0056] R c =(M+M V )α…Formula 6

[0057] [Formula 7]

[0058]

[0059] [Formula 8]

[0060] T W =T M *R G ...Equation 8

[0061] [Formula 9]

[0062]

[0063] [Formula 10]

[0064]

[0065] [Formula 11]

[0066] θ W =∫ω W dt…Equation 11

[0067] [Formula 12]

[0068] θ M =∫ω M dt…Equation 12

[0069] [Formula 13]

[0070] T D =S D (θ M -R G θ W )...Equation 13

[0071] Furthermore, in formulas (1) to (13), F V is the force acting on the moving vehicle, V V is the vehicle speed, α V is the acceleration, M V is the vehicle weight, Mi is the equivalent inertial mass of the rotating part of the drive system, A V is the front projection area, R G is the total reduction ratio, F W is the wheel axle propulsion force, T W is the wheel axle torque, J W is the vehicle inertia converted to wheel axle, ω W is the wheel speed, θ W is the rotation angle of the wheel, R W is the radius of the wheel, F B is the braking force generated by the mechanical brake, S D is the rigidity of the transmission shaft, T D is the torsional moment of the transmission shaft, T M is the motor shaft torque, J M is the inertia on the motor side, ω M is the motor speed, θ M is the rotation angle of the motor, R t is the driving resistance, R a is the air resistance, C d is the air resistance coefficient, ρ is the air density, R r is the rolling resistance, μ is the rolling resistance coefficient, θ is the slope, g is the acceleration of gravity, R e is the slope resistance, R c The acceleration resistance.

[0072] Hereinafter, the force exerted on the motor 930 by the vehicle body 9, that is, the output of the three accelerometers 950, is referred to as "first information," and the model of the vehicle 9 equipped with the motor, the part number information of components other than the motor 930, the wheel radius, the vehicle speed, the wheel rotational speed, and the battery DC voltage value are referred to as "second information." The first information generating unit 11 generates the first information using the output of the accelerometer 950. The second information generating unit 12 generates the second information using the output of the wheel air pressure sensor, the speed of the vehicle 9, and the rotational speed output of the wheel speed sensors installed on the brake devices 907A-D. Furthermore, in addition to the above, weather conditions such as temperature and humidity, as well as slope information, can be provided by dedicated sensors in the vehicle 9, or regional information can be aggregated and used in the server 20.

[0073] As previously mentioned, the server storage unit 30 of the server 20 stores component information 31, physical property values ​​32, a vehicle database 33, stress information 34, and fatigue limit information 35. Component information 31 includes information on the shapes of various components installed in the vehicle 9 and the materials used for each component. Physical property values ​​32 include various mechanical and electrical characteristics of each material, such as breaking strength and dielectric strength. The model of the vehicle 9 and the part number of components other than the motor 930 are transmitted as part of the second information and compared with the component information in the server storage unit 30.

[0074] The stress calculation unit 21 of the server 20 calculates the stress applied to the motor 930 by simulation using equations (1) to (12) based on the first information and the second information, and stores the calculated stress as stress information 34 for each component of the motor 930. Furthermore, the number calculation unit 22 of the server 20 calculates the number of repetitions until fatigue failure occurs for each stress based on the physical properties of the raw materials of the motor 930, and stores the calculated stress as fatigue limit information 35.

[0075] Figure 5 FIG is a diagram showing an example of stress information 34. Figure 5 As shown, the stress information 34 stores the stress and times of each structural part of the motor.

[0076] Figure 6 This is a conceptual diagram of fatigue limit information 35. Fatigue limit information 35 is prepared for each part such as the motor and the vehicle mounting part. Figure 6 Shown is a part of the motor. Figure 6 In FIG. 3 , the fatigue limit information 35 is shown in a graph for easy understanding, but the fatigue limit information 35 can also be shown in a table or a numerical expression. Figure 6 In the figure, the horizontal axis represents the number of repetitions, and the vertical axis represents stress. The greater the stress, the smaller the number of repetitions until fatigue failure occurs. Figure 6 The example shown shows the following situation: when the stress σ1-1 is repeated the number of times reaches N1-1, fatigue failure occurs. Figure 6 As shown, fatigue failure may not occur when the stress is less than the fatigue limit, or fatigue failure may be affected even when the stress is less than the fatigue limit by using a modified Meiner's law.

[0077] Figure 7 3 is a diagram showing an example of the vehicle database 33. The vehicle database 33 stores the vehicle identification number and the accumulated value of fatigue level of each component. Figure 7 In the example shown, only the fatigue levels of the motor and the inverter are described. However, the components are not limited to the motor and the inverter, and various components mounted in the vehicle are targeted.

[0078] When the fatigue assessment unit 23 receives the first information 41 and the second information 42 from the onboard device 10, it first calculates the stress by referring to the stress information 34. Next, the fatigue assessment unit 23 calculates the incremental fatigue level by referring to the fatigue limit information 35. The fatigue assessment unit 23 then adds the calculated incremental fatigue level to the fatigue level recorded in the vehicle database 33 and determines whether the total fatigue level exceeds 1.0. If the total fatigue level is determined to be greater than 1.0, the fatigue assessment unit 23 transmits a warning signal to the onboard device 10 that previously transmitted the first information 41 and the second information 42. If the total fatigue level is determined to be less than 1.0, the fatigue assessment unit 23 transmits a signal to the onboard device 10 that previously transmitted the first information 41 and the second information 42, indicating that driving is safe.

[0079] (flow chart)

[0080] Figure 8 The in-vehicle device 10 is a flowchart showing the operation of the in-vehicle device 10. The in-vehicle device 10 executes the operation at a predetermined time, for example, when the in-vehicle device 10 is started or every hour. Figure 8 The processing shown in FIG. In step S301, the first information generating unit 11 and the second information generating unit 12 acquire sensor information. In the following step S302, the first information generating unit 11 and the second information generating unit 12 create first information and second information. The first information and second information transmitted in step S302 preferably include information covering the entire period during which the vehicle 9 is operating.

[0081] Therefore, for example, if step S302 is executed once an hour, it is ideal to aggregate and transmit the first and second information corresponding to the sensor information for the past hour. Regarding the information transmitted in step S302, for example, the first information may be the detection values ​​of the three accelerometers (fx11, fy11, fz11), (fx12, fy12, fz12), and (fx13, fy13, fz13), and the second information may be time-series curve data such as (fx21, fy21, yz21). Alternatively, the power spectral density at the position of each accelerometer over a certain period of time may be calculated and transmitted instead of the time series data of the detection values ​​of each accelerometer.

[0082] In the next step S303, the external vehicle communication unit 14 transmits the first and second information generated in step S302 to the server 20. In the next step S303, the external vehicle communication unit 14 waits for a response from the server 20. Upon receiving a response, the process proceeds to step S305. In step S305, the notification unit 16 determines whether the vehicle 9 can travel. If it determines that travel is possible, the process proceeds to step S306; if it determines that travel is not possible, the process proceeds to step S307. For example, if the response from the server 20 indicates that travel is possible, the notification unit 16 proceeds to step S306; if the response from the server 20 indicates that travel is possible, the notification unit 16 proceeds to step S307.

[0083] In step S306, the notification unit 16 outputs that there is no problem and ends the process. Figure 8 In step S307, the notification unit 16 notifies that a problem may occur during driving, and ends the process. Figure 8 Furthermore, in step S307, when the vehicle control unit 15 is controlling the vehicle 9, the vehicle's running state may be changed by switching to a limp home mode or the like.

[0084] Figure 9 The flow chart showing the operation of the server 20. When the server 20 receives a communication from the vehicle-mounted device 10, it starts Figure 9 The server communication unit 24 of the server 20 first receives the first information and the second information from the vehicle-mounted device 10 in step S401. In this step, an identifier identifying the vehicle on which the vehicle-mounted device 10 is mounted and the name of the component to be diagnosed may also be received. In the following step S402, the fatigue assessment unit 23 refers to the stress information 34 to calculate the stress corresponding to the first information and the second information received in step S401. Furthermore, if there are multiple combinations of the first information and the second information received in step S401, stress is calculated for all of these combinations in step S402.

[0085] In the next step S403, the fatigue assessment unit 23 refers to the fatigue limit information 35 to calculate the increase in fatigue level due to the stress calculated in step S402. For example, assume that there is only one combination of the first and second information received in step S401, and the stress corresponding to this combination is determined to be "σ1" by referring to the stress information 34. In this case, if the number of times corresponding to stress "σ1" in the fatigue limit information 35 is "1000" and the number of times the aforementioned combination received in step S401 is "10", the increase in fatigue level is "0.01", which is the value obtained by dividing "10" by "1000".

[0086] In the following step S404, the fatigue assessment unit 23 reads the fatigue level of the vehicle that transmitted the first information, etc., from the vehicle database 33 and updates the fatigue level by adding the value calculated in step S403. The vehicle is identified in this step using, for example, the vehicle identifier received along with the first and second information in step S401. The component to be diagnosed is identified in this step by using the component name received in step S401 if the component has been previously identified. Otherwise, the component name received in step S401 is used.

[0087] In step S404, for example, if the vehicle identifier is determined to be "abc002", the increment calculated in step S403, i.e., "0.01", is added to Figure 7 In the next step S405, the fatigue evaluation unit 23 determines whether the fatigue level after the update in step S404 is less than a predetermined threshold value, i.e., "1". If it is determined to be less than "1", the process proceeds to step S406. If it is determined to be greater than "1", the process proceeds to step S407. In step S406, the fatigue evaluation unit 23 notifies that there is no problem with the vehicle and ends the process. Figure 9 In step S407, the fatigue evaluation unit 23 notifies the vehicle of a warning and ends the process. Figure 9 The processing shown.

[0088] According to the first embodiment described above, the following effects are achieved.

[0089] (1) The on-vehicle device 10 is mounted in the vehicle 9 and communicates with the server 20. The on-vehicle device 10 includes: a first information generating unit 11 that uses the output of an accelerometer 950, a sensor mounted in the vehicle 9, to generate first information related to the state of a motor 904, a component mounted in the vehicle 9; and an off-vehicle communication unit 14 that transmits the first information and second information related to the state of a component other than the motor 904, namely, a transmission shaft 906, to the server 20, and receives from the server 20 a status signal indicating an abnormal state of the first component, which is calculated by the server 20 based on the first information and the second information. Therefore, an abnormality of the first component can be detected with high accuracy.

[0090] (2) The vehicle-mounted device 10 includes a vehicle control unit 15 that changes the driving state of the vehicle 9 based on the state signal received by the external communication unit 14. When an abnormality is detected in a component, safety measures such as slowing the vehicle 9 can be taken.

[0091] (3) The vehicle-mounted device 10 includes the notification unit 16 that notifies the occupants of the vehicle 9 of the status signal received by the external communication unit 14. Therefore, the optimal control of the vehicle 9 can be delegated to the occupants.

[0092] (4) The first component is the motor 904. The first information is the output of the accelerometer 950 provided at the connection portion between the motor 904 and the vehicle 9. The second information includes the rotational speed of the transmission shaft 906 that is directly or indirectly mechanically connected to the motor 904.

[0093] (5) The first component is the motor 904, and the first information is the voltage value applied to the coil of the motor 904. The server 20 calculates the abnormal state of the first component using the air pressure in addition to the first information and the second information.

[0094] (6) The operation system S includes a server 20 and an onboard device 10 mounted in the vehicle 9, which are capable of communicating with each other. The onboard device 10 includes: a first information generating unit 11 that generates first information related to the state of a component mounted in the vehicle 9, namely, a motor 904; and an off-vehicle communication unit 14 that transmits the first information and second information related to the state of the transmission shaft 906 to the server 20. The server 20 includes: a fatigue evaluation unit 23 that calculates a state signal indicating an abnormal state of the first component based on the first information and the second information; and a server communication unit 24 that transmits the state signal to the onboard device 10. The off-vehicle communication unit 14 of the onboard device 10 receives the state signal.

[0095] (7) The server 20 includes a server storage unit 30 that stores a vehicle database 33. The vehicle database 33 stores accumulated fatigue values ​​of the first component. The server storage unit 30 stores fatigue limit information 35 that can calculate the amount of increase in fatigue of the first component using the first information and the second information. The fatigue evaluation unit 23 of the server 20 calculates the amount of increase in fatigue using the first information and the second information received from the vehicle-mounted device 10 and the fatigue limit information 35 stored in the server storage unit 30. When the sum of the accumulated fatigue value stored in the server storage unit 30 and the amount of increase in fatigue exceeds a predetermined threshold, the server determines that the first component is in an abnormal state.

[0096] (Variation 1)

[0097] The server 20 includes a stress calculation unit 21 and a frequency calculation unit 22, and the server storage unit 30 contains component information 31 and physical property values ​​32. However, a computing device or computing unit other than the vehicle-mounted device 10 and the server 20 may generate stress information 34 and fatigue limit information 35 and store them in the server storage unit 30. In this case, the server 20 may not be equipped with the stress calculation unit 21 and the frequency calculation unit 22, and the server storage unit 30 may not store the component information 31 and physical property values ​​32.

[0098] (Variation 2)

[0099] exist Figure 8 In step S306, the notification unit 16 may not perform a special output. That is, if no abnormality is detected, the notification unit 16 may not perform an action. Furthermore, if the vehicle control unit 15 performs an action, the notification unit 16 may perform an action. Figure 8 In other words, at least one of the notification unit 16 and the vehicle control unit 15 only needs to operate in step S307.

[0100] (Variation 3)

[0101] The computing system can also detect electrical fatigue, i.e., insulation failure. In this variation, the server 20 further includes an insulation calculation unit 25, and the server storage unit 30 further stores insulation information 36. Furthermore, while this variation describes the detection of insulation failure instead of fatigue failure, the computing system can also detect insulation failure in addition to fatigue failure.

[0102] The insulation breakdown in the coils of motor 930 is affected by the impedance of motor 930, the temperature of the coils of motor 930, the DC voltage of battery 910, the carrier frequency of inverter 920, the impedance of AC power cable 925, the voltage fluctuation amplitude of battery 910, atmospheric pressure, and humidity. The insulation breakdown in the coils of motor 930 occurs due to a reduction in the thickness of the enamel film of the enameled wire.

[0103] The coil temperature and impedance of motor 930 are also referred to as "first information regarding insulation breakdown." The detection value of the DC voltage sensor of battery 910 or the detection value of the DC voltage sensor of inverter 920, the carrier frequency of inverter 920, and the impedance of AC power cable 925 are also referred to as "second information regarding insulation breakdown." Information regarding air pressure and humidity can be obtained by adding sensors to vehicle 9, or by transmitting values ​​observed by a base station near the vehicle to server 20 for use.

[0104] The DC voltage of the battery 910 varies according to the state of charge SOC (STATE OF CHARGE) of the battery 910 and the internal resistance of the battery 910. Figure 2 The voltage V between the terminal U of the inverter 920 and the reference potential N of the battery 910 is shown. UN The amplitude of the voltage pulse waveform is as follows Figure 10 As shown in the upper layer, the voltage V of the battery 910 PN Therefore, when the SOC is low, the amplitude of the voltage pulse is low, and when the SOC is high, the amplitude of the voltage pulse is high. Therefore, even if the fundamental component of the voltage applied by the inverter is the same, the SOC of battery 910 will cause the pulse waveform of the voltage applied by the inverter to differ.

[0105] Furthermore, the AC-side terminals U, V, and W of inverter 920 are connected to the terminals U', V', and W' of motor 930 via AC power cable 925. At this point, because the impedance of AC power cable 925 differs significantly from that of motor 930, a voltage pulse is reflected at the terminals U', V', and W' of motor 930. This results in a sudden voltage jump at the terminals U', V', and W' of motor 930 during power-on and power-off, a phenomenon known as inverter surge voltage.

[0106] The voltage V between the terminal U of the inverter 920 and the reference potential N of the battery 910 UN The voltage pulse waveform and the voltage V between the terminal U' of the motor 930 and the reference potential N of the battery 910 U'N The voltage pulse waveform is shown in Figure 10 A voltage k times the voltage amplitude of the battery 910 is applied instantaneously to the terminals U', V', and W' of the motor 930 due to reflection of the voltage pulse when the motor 930 is turned on or off. In this case, k≧1.

[0107] The development of insulation breakdown caused by age-related degradation of motor 930 is influenced by temperature-related degradation of the enamel film of the enameled wire, the material of the motor 930 coil; changes in the partial discharge inception voltage due to air pressure; the surge voltage coefficient k caused by the mismatch between the impedance of motor 930 and the impedance of the AC power cable; the number of surge voltage applications determined by the carrier frequency of inverter 920; and the DC voltage of battery 910. The surge voltage from inverter 920 erodes the enamel film of the enameled wire, reducing its thickness until insulation breakdown occurs.

[0108] The insulation calculation unit 25 of the server 20 obtains the impedance of the motor 930 and the temperature of the motor 930 coil as first information. The insulation calculation unit 25 obtains the DC voltage of the battery 910, the carrier frequency of the inverter 920, and the impedance of the AC power cable 925 as second information, and obtains the atmospheric pressure and humidity as external information. The insulation calculation unit 25 then uses simulation to calculate the number of times it takes for coil insulation to occur under each condition.

[0109] Then, insulation calculation unit 25 records the inverse of this number of times as the characteristic value of this condition in insulation information 36. For example, if insulation breakdown occurs in the coil of motor 904 when the combination of motor 930 impedance, motor 930 coil temperature, battery 910 DC voltage, inverter 920 carrier frequency, AC power cable 925 impedance, and external information such as air pressure and humidity occurs 100 times, the characteristic value of this combination is 1 / 100, or "0.01."

[0110] Furthermore, the thickness of the enamel film of the enameled wire constituting the coil of the motor 930 may be used as a feature value, and a fault may be determined when the thickness of the enamel film of the enameled wire constituting the coil of the motor 930 becomes below a certain threshold.

[0111] Figure 11 3 is a diagram showing an example of the insulation information 36. The insulation information 36 stores the characteristic amount calculated by the insulation calculation unit 25 for each combination of the voltage variation range of the battery 901, the impedance of the power cable 902, and the air pressure.

[0112] In this modification, the vehicle database 33 stores feature quantities accumulated so far instead of fatigue levels.

[0113] The first information generating unit 11 transmits the impedance of the motor 930 and the temperature detected by the temperature sensor attached to the coil of the motor 930 to the server 20 as first information about the motor 930. The second information generating unit 12 measures the voltage of the battery 901 built into the battery 910, the voltage of the battery 901 built into the inverter 920, the carrier frequency of the inverter 903, and the impedance of the AC power cable 925, or reads the known impedance of the AC power cable 925 from a ROM (not shown) or the like, and transmits the second information on insulation breakdown to the server 20.

[0114] Upon receiving the first and second information, fatigue assessment unit 23 of server 20 references insulation information 36 to obtain a characteristic value and adds the obtained characteristic value to the characteristic value stored in vehicle database 33. If the value is 1 or greater, server 20 notifies vehicle-mounted device 10 of a warning; if it is less than 1, server 20 notifies vehicle-mounted device 10 that there is no problem.

[0115] According to this modification 3, electrical fatigue can be detected.

[0116] (Variation 4)

[0117] The fatigue evaluation unit 23 of the server 20 can also change the specified threshold value in the evaluation of fatigue. Specifically, the fatigue evaluation unit 23 can use the second information to change the threshold value for comparison in step S405 from "1" to other values ​​such as "1.2" or "0.8". For example, when it is confirmed that the diagnostic object deteriorates quickly when used for a long time in an area with high altitude, that is, an area with low air pressure, the threshold value is changed from "1" to a value less than 1 based on the air pressure information contained in the second information. The specific value is determined by referring to a database (not shown) that is pre-produced and stored in the server 20. Furthermore, the database (not shown) can be produced by collecting a large number of comparison cases of the actual degradation conditions of components in the regular maintenance of the vehicle and the degradation conditions inferred based on the first information and the second information related to the vehicle to date.

[0118] Figure 12 This is a conceptual diagram of the process of changing the threshold value by the fatigue evaluation unit 23 . Figure 12 In FIG. 1 , symbol L1 represents an initial threshold value, such as “1”, symbol L2 represents an increased threshold value, such as “1.2”, and symbol L3 represents a decreased threshold value, such as “0.8”.

[0119] According to this modification example 4, the following effects are obtained.

[0120] (8) The fatigue evaluation unit 23 of the server 20 changes the predetermined threshold value based on the second information. Therefore, an abnormality of the first component can be detected with higher accuracy.

[0121] -Second embodiment-

[0122] refer to Figure 13 , a second embodiment of the computing system is described. In the following description, the same reference numerals are used for the same components as in the first embodiment, and the differences are mainly described. Aspects not specifically described are the same as in the first embodiment. The main difference between this embodiment and the first embodiment is that the processing is performed within the vehicle-mounted device.

[0123] Figure 13 This is a diagram showing the configuration of the vehicle-mounted device 10A in the second embodiment. In addition to the configuration of the first embodiment, the vehicle-mounted device 10A further includes a fatigue assessment unit 23 and a vehicle-mounted storage unit 130. The vehicle-mounted storage unit 130 stores stress information 34 and fatigue limit information 35. The vehicle-mounted storage unit 130 also stores information on the fatigue levels of components of the vehicle 9. The fatigue assessment unit 23 has the same function as the fatigue assessment unit 23 provided in the server 20 in the first embodiment. The vehicle-mounted storage unit 130 is a non-volatile storage device such as a flash memory. The stress information 34 and fatigue limit information 35 are the same as the information of the same name stored in the server storage unit 30 in the first embodiment. In this embodiment, the vehicle-mounted device 10A may not include the off-vehicle communication unit 14.

[0124] In this embodiment, the vehicle-mounted device 10A performs the operation in the first embodiment. Figure 8 and Figure 9 The two-way processing is performed. Specifically, sensor information is first acquired (S301), and the first information generation unit 11 and the second information generation unit 12 generate the first information and the second information, respectively (S302). Next, the fatigue evaluation unit 23 calculates stress and updates the fatigue level stored in the onboard storage unit 130 (S402-S404). Subsequently, processing is performed according to the magnitude of the updated fatigue level (S405, S306, and S307).

[0125] According to the second embodiment described above, the following effects are achieved.

[0126] (9) The onboard device 10A is mounted on the vehicle 9. The onboard device 10A includes: a first information generating unit 11 that generates first information related to the state of a first component mounted on the vehicle using outputs from sensors mounted on the vehicle 9; and an onboard storage unit 130 that stores a cumulative value of fatigue of the first component. The onboard storage unit 130 stores fatigue limit information 35 that can calculate the increase in fatigue of the first component using the first information and second information related to the state of a second component other than the first component. The onboard device 10A includes a fatigue evaluation unit 23 that calculates the increase in fatigue using the first information, the second information, and the fatigue limit information 35. When the sum of the cumulative value of fatigue stored in the onboard storage unit 130 and the increase in fatigue exceeds a predetermined threshold, the onboard device 10A determines that the first component is in an abnormal state. Therefore, the vehicle-mounted device 10A can obtain the same operational effects as those of the first embodiment without performing communication with the server 20 .

[0127] In the above-mentioned embodiments and variations, the functional block configuration is merely an example. Several functional configurations presented as separate functional blocks may be integrated, or a configuration represented by a single functional block diagram may be divided into two or more functions. Furthermore, a configuration may be provided in which a portion of the functions of each functional block is performed by another functional block.

[0128] The above embodiments and modifications may also be combined. In the above, various embodiments and modifications have been described, but the present invention is not limited to these contents. Other forms that can be considered within the scope of the technical idea of ​​the present invention are also included in the scope of the present invention.

[0129] Explanation of symbols

[0130] 9…Vehicle, 10, 10A…In-vehicle device, 11…First information generating unit, 12…Second information generating unit, 15…Vehicle control unit, 16…Notification unit, 20…Server, 21…Stress calculating unit, 22…Number calculating unit, 23…Fatigue evaluation unit, 30…Server storage unit, 31…Component information, 32…Physical property value, 33…Vehicle database, 34…Stress information, 35…Fatigue limit information, 36…Insulation information, 41…First information, 42…Second information, 910…battery, 911…DC power cable, 920…inverter, 921…smoothing capacitor, 922…power module, 923…IGBT, 924…diode, 925…AC power cable, 930…motor, 931…motor rotation angle detector, 940…gearbox, 950…accelerometer, 906…drive shaft, 907A, 907B, 907C, 907D…brake system, 908A, 908B, 908C, 908D…wheels.

Claims

1. A vehicle-mounted device, which is mounted in a vehicle and communicates with a server, characterized in that: have: a first information generating unit for generating first information related to a state of a first component mounted on the vehicle using an output of a sensor mounted on the vehicle; as well as an off-vehicle communication unit that transmits the first information and second information related to the status of a second component different from the first component to the server, and receives from the server a status signal indicating an abnormal state of the first component calculated by the server based on the first information and the second information, The first component is a motor, The first information is a voltage value applied to the coil of the motor. The server calculates the abnormal state of the first component using air pressure in addition to the first information and the second information.

2. The vehicle-mounted device according to claim 1, wherein: A vehicle control unit is provided, which changes the driving state of the vehicle based on the state signal received by the external vehicle communication unit.

3. The vehicle-mounted device according to claim 1, wherein: A notification unit is provided for notifying an occupant of the vehicle of the state signal received by the vehicle external communication unit.

4. The vehicle-mounted device according to claim 1, wherein The first information is the output of an accelerometer provided at a connection portion between the motor and the vehicle. The second information includes the rotational speed of a transmission shaft that is directly or indirectly mechanically connected to the motor.

5. A communication system comprising a server and an on-board device mounted in a vehicle that can communicate with each other, characterized in that: The vehicle-mounted device comprises: a first information generating unit for generating first information related to a state of a first component mounted on the vehicle using an output of a sensor mounted on the vehicle; as well as an off-vehicle communication unit that transmits the first information and second information related to the state of a second component that is different from the first component to the server, The server has: a fatigue evaluation unit that calculates a state signal indicating an abnormal state of the first component based on the first information and the second information; and a server communication unit that sends the status signal to the vehicle-mounted device; The vehicle-mounted device's external communication unit receives the status signal, The first component is a motor, The first information is a voltage value applied to the coil of the motor. The server calculates the abnormal state of the first component using air pressure in addition to the first information and the second information.

6. The communication system according to claim 5, characterized in that The server further includes a server storage unit storing a vehicle database storing accumulated values ​​of fatigue levels of the first component. The server storage unit further stores fatigue limit information capable of calculating an increase in fatigue level of the first component using the first information and the second information. The fatigue evaluation unit of the server calculates the increase in fatigue level using the first information and the second information received from the vehicle-mounted device and the fatigue limit information stored in the server storage unit. When the sum of the accumulated value of fatigue level stored in the server storage unit and the increase in fatigue level exceeds a prescribed threshold value, the server determines that the first component is in an abnormal state.

7. The communication system according to claim 6, wherein: The fatigue assessment unit of the server changes the predetermined threshold value based on the second information.

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