JP2023029029A - On-vehicle system, program, information processing method and second on-vehicle ecu - Google Patents

Abstract

To provide an on-vehicle system which can efficiently control a plurality of on-vehicle devices mounted on a vehicle.SOLUTION: An on-vehicle system includes a first on-vehicle ECU which is mounted on the vehicle and controls a semiconductor fuse, and a second on-vehicle ECU which is communicably connected to the first on-vehicle ECU, wherein the first on-vehicle ECU detects a current value applied to the semiconductor fuse and outputs the detected current value to the second on-vehicle ECU, the second on-vehicle ECU derives a shut-off current threshold on the basis of a current value acquired from the first on-vehicle ECU, outputs the derived shut-off current threshold to the first on-vehicle ECU, and the first on-vehicle ECU shuts off the semiconductor fuse according to the shut-off current threshold acquired from the second on-vehicle ECU.SELECTED DRAWING: Figure 1

Description

The present invention relates to an in-vehicle system, a program, an information processing method, and a second in-vehicle ECU.

A vehicle is equipped with a body ECU, which is an in-vehicle ECU that controls body devices such as a wiper drive device, lighting devices inside and outside the vehicle, door lock devices, power windows, etc. (for example, patent Reference 1). The wiper drive device of Patent Document 1 includes an in-vehicle ECU (body ECU) and is driven by a control program applied to the in-vehicle ECU.

JP 2017-224926 A

However, in the driving device of Patent Document 1, in a configuration including an in-vehicle device that is directly connected to an actuator to be driven and an in-vehicle device that transmits a control signal to the in-vehicle device, control between the plurality of in-vehicle devices is performed. Efficiency is not considered.

An object of the present disclosure is to provide an in-vehicle system or the like capable of efficiently controlling a plurality of in-vehicle devices mounted in a vehicle.

An in-vehicle system according to an aspect of the present disclosure is an in-vehicle system that is mounted in a vehicle and includes a first in-vehicle ECU that controls a semiconductor fuse and a second in-vehicle ECU that is communicatively connected to the first in-vehicle ECU. The first vehicle-mounted ECU detects a current value flowing through the semiconductor fuse and outputs the detected current value to the second vehicle-mounted ECU, and the second vehicle-mounted ECU receives the current obtained from the first vehicle-mounted ECU. Based on the value, a breaking current threshold is derived, the derived breaking current threshold is output to the first vehicle-mounted ECU, and the first vehicle-mounted ECU responds to the breaking current threshold acquired from the second vehicle-mounted ECU, The semiconductor fuse is broken.

According to one aspect of the present disclosure, it is possible to provide an in-vehicle system or the like that efficiently controls a plurality of in-vehicle devices mounted in a vehicle.

1 is a schematic diagram illustrating a system configuration of an in-vehicle system (integrated ECU, individual ECU) according to Embodiment 1; FIG. 3 is a block diagram illustrating the internal configuration of an integrated ECU and the like; FIG. FIG. 4 is an explanatory diagram illustrating a flow (sequence) of processing by individual ECUs and an integrated ECU; FIG. 5 is an explanatory diagram illustrating an example of a cutoff temperature threshold and the like; 4 is a flowchart illustrating processing of a control unit such as an integrated ECU;

[Description of the embodiment of the present invention]
First, embodiments of the present disclosure are enumerated and described. Moreover, at least part of the embodiments described below may be combined arbitrarily.

(1) An in-vehicle system according to an aspect of the present disclosure includes a first in-vehicle ECU mounted in a vehicle and controlling a semiconductor fuse, and a second in-vehicle ECU communicably connected to the first in-vehicle ECU. In the system, the first vehicle-mounted ECU detects a current value flowing through the semiconductor fuse and outputs the detected current value to the second vehicle-mounted ECU, and the second vehicle-mounted ECU receives the current value from the first vehicle-mounted ECU. Based on the acquired current value, a breaking current threshold is derived, the derived breaking current threshold is output to the first vehicle-mounted ECU, and the first vehicle-mounted ECU uses the breaking current threshold acquired from the second vehicle-mounted ECU. Accordingly, the semiconductor fuse is cut.

In this aspect, the first vehicle-mounted ECU (individual ECU) acquires from the second vehicle-mounted ECU a breaking current threshold derived based on the current value flowing through the semiconductor fuse detected at the present time. Based on the breaking current threshold, the semiconductor fuse is controlled by the first vehicle-mounted ECU (individual ECU) alone. The breaking current threshold corresponds to (corresponds to) the temperature at which the semiconductor fuse needs to be broken (breaking temperature threshold). By using the breaking current threshold derived (predicted) by the second on-vehicle ECU, the first on-vehicle ECU alone determines whether or not the temperature of the wire to which the semiconductor fuse is connected reaches the breaking temperature threshold. can be done. An in-vehicle system consists of a first in-vehicle ECU (individual ECU) that is directly connected to a drive unit (actuator) to be controlled, and a second in-vehicle ECU (integrated ECU) that performs various processes related to control of the drive unit. , are separate in-vehicle devices. Even with such a configuration, the first in-vehicle ECU (individual ECU) can independently shut down a process requiring immediate effect (urgentness) such as shutting off a semiconductor fuse. That is, for example, even if the communication load (traffic) on the communication line between the first in-vehicle ECU (individual ECU) and the second in-vehicle ECU (integrated ECU) increases and communication delays occur, 1 The in-vehicle ECU (individual ECU) can cut off the semiconductor fuse by itself, and can further improve the reliability of the vehicle. In this way, even when a plurality of in-vehicle devices each composed of a plurality of first in-vehicle ECUs (individual ECUs) and second in-vehicle ECUs (integrated ECU) are mounted in the vehicle, the control in these plurality of in-vehicle devices can be efficiently performed. can be done systematically.

(2) In the in-vehicle system according to an aspect of the present disclosure, the second in-vehicle ECU derives the temperature of the electric wire to which the semiconductor fuse is connected based on the current value acquired from the first in-vehicle ECU, and is greater than or equal to a predetermined alert temperature threshold, the breaking current threshold is derived.

In this aspect, the second vehicle-mounted ECU derives and outputs a breaking current threshold when the wire temperature (wire temperature) derived based on the current value obtained from the first vehicle-mounted ECU is equal to or higher than the warning temperature threshold. The warning temperature threshold is stored, for example, in the storage section of the second vehicle-mounted ECU, and the second vehicle-mounted ECU can acquire the warning temperature threshold by referring to the storage section. As a result, excessive derivation and output of the breaking current threshold can be suppressed, and the processing load on the first vehicle-mounted ECU and the second vehicle-mounted ECU can be reduced.

(3) In the in-vehicle system according to an aspect of the present disclosure, the second in-vehicle ECU derives the breaking current threshold based on the temperature of the wire to which the semiconductor fuse is connected and the characteristic parameter of the wire.

In this aspect, the second vehicle-mounted ECU derives the breaking current threshold based on the temperature of the wire to which the semiconductor fuse is connected (wire temperature) and the characteristic parameters such as the material, length, and thickness of the wire. , the derivation accuracy of the breaking current threshold can be improved.

(4) In the in-vehicle system according to one aspect of the present disclosure, the first in-vehicle ECU cuts off the semiconductor fuse when the current value flowing through the semiconductor fuse is equal to or greater than the cut-off current threshold.

In this aspect, the first vehicle-mounted ECU continuously detects the current value flowing through the semiconductor fuse at a predetermined cycle, and the detected current value is equal to or greater than the breaking current threshold acquired immediately before from the second vehicle-mounted ECU. In the case of , control (OFF control) is performed to cut off the semiconductor fuse. As a result, the semiconductor fuse can be cut off efficiently.

(5) In an in-vehicle system according to an aspect of the present disclosure, when the first in-vehicle ECU cuts off the semiconductor fuse according to the cut-off current threshold, the second in-vehicle ECU connects a wire to which the semiconductor fuse is connected. temperature, a return signal for restarting energization of the semiconductor fuse is output to the first vehicle-mounted ECU.

In this aspect, when the first in-vehicle ECU cuts off the semiconductor fuse according to the breaking current threshold, the second in-vehicle ECU acquires the wire temperature continuously detected by the first in-vehicle ECU, and the wire temperature is sufficiently high. When the temperature drops to a relatively low temperature (recovery temperature), a recovery signal is output to the first on-vehicle ECU to resume energization of the semiconductor fuse. As a result, it is possible to reliably restore (restart energization of) the interrupted semiconductor fuse.

(6) An information processing method according to an aspect of the present disclosure is an information processing method that causes a first computer that controls a semiconductor fuse and a second computer that is communicably connected to the first computer to execute processing, The first computer detects the current value flowing through the semiconductor fuse, outputs the detected current value to the second computer, and outputs the current value obtained from the first computer to the second computer, breaking current based on the current value acquired from the first computer A signal for deriving a threshold, outputting the derived breaking current threshold to the first computer, and providing the first computer with a signal for breaking the semiconductor fuse according to the breaking current threshold obtained from the second computer. is executed.

In this aspect, it is possible to provide an information processing method that causes the first computer and the second computer to function as an in-vehicle system that efficiently controls a plurality of in-vehicle devices mounted in the vehicle.

(7) A program according to one aspect of the present disclosure is a program that causes a first computer that controls a semiconductor fuse and a second computer that is communicatively connected to the first computer to execute processing, wherein the first computer a current value flowing through the semiconductor fuse is detected, the detected current value is output to the second computer, and a breaking current threshold value is derived to the second computer based on the current value obtained from the first computer. a process of outputting the derived breaking current threshold to the first computer, and outputting a signal for breaking the semiconductor fuse to the first computer according to the breaking current threshold obtained from the second computer; to run.

In this aspect, the first computer and the second computer can function as an in-vehicle system that efficiently controls a plurality of in-vehicle devices mounted in the vehicle.

(8) A second in-vehicle ECU according to an aspect of the present disclosure is a second in-vehicle ECU mounted in a vehicle and communicably connected to a first in-vehicle ECU that controls a semiconductor fuse, wherein the first in-vehicle ECU wherein the control unit acquires a current value flowing through the semiconductor fuse from the first vehicle-mounted ECU, derives a breaking current threshold value based on the acquired current value, and derives the By outputting the breaking current threshold to the first vehicle-mounted ECU, the first vehicle-mounted ECU is caused to break the semiconductor fuse according to the breaking current threshold.

In this aspect, it is possible to provide a second vehicle-mounted ECU included in the vehicle-mounted system capable of efficiently controlling a plurality of vehicle-mounted devices mounted on the vehicle.

(9) An information processing method according to an aspect of the present disclosure acquires a current value flowing through the semiconductor fuse from the first vehicle-mounted ECU to a computer communicably connected to the first vehicle-mounted ECU that controls the semiconductor fuse. Then, based on the acquired current value, a breaking current threshold is derived, and the derived breaking current threshold is output to the first vehicle-mounted ECU, thereby breaking the semiconductor fuse according to the breaking current threshold. 1. Execute the processing to be executed by the in-vehicle ECU.

In this aspect, it is possible to provide an information processing method that causes a computer to function as a second vehicle-mounted ECU included in an vehicle-mounted system capable of efficiently controlling a plurality of vehicle-mounted devices mounted on a vehicle.

(10) A program according to an aspect of the present disclosure acquires a current value flowing through the semiconductor fuse from the first vehicle-mounted ECU to a computer communicably connected to the first vehicle-mounted ECU that controls the semiconductor fuse, A breaking current threshold value is derived based on the obtained current value, and the derived breaking current threshold value is output to the first vehicle-mounted ECU, thereby breaking the semiconductor fuse according to the breaking current threshold value to the first vehicle-mounted ECU. It causes the ECU to execute the processing.

In this aspect, the computer can function as a second vehicle-mounted ECU included in the vehicle-mounted system capable of efficiently controlling a plurality of vehicle-mounted devices mounted on the vehicle.

[Details of the embodiment of the present disclosure]
The present disclosure will be specifically described based on the drawings showing the embodiments thereof. An in-vehicle system S according to an embodiment of the present disclosure will be described below with reference to the drawings. The present disclosure is not limited to these examples, but is indicated by the scope of the claims, and is intended to include all modifications within the scope and meaning equivalent to the scope of the claims.

(Embodiment 1)
Embodiments will be described below with reference to the drawings. FIG. 1 is a schematic diagram illustrating the system configuration of an in-vehicle system S (integrated ECU 6, individual ECU 2) according to the first embodiment. FIG. 2 is a block diagram illustrating the internal configuration of the integrated ECU 6 and the like. The in-vehicle system S includes an integrated ECU 6 and a plurality of individual ECUs 2 mounted in the vehicle C, and the in-vehicle devices 3 such as actuators 30 and sensors 31 are directly connected to the individual ECUs 2 . The separate ECU 2 corresponds to the first vehicle-mounted ECU, and the integrated ECU 6 corresponds to the second vehicle-mounted ECU.

The individual ECUs 2 are arranged in each area of the vehicle C, and actuators 30 such as car air conditioners, wipers, and lamps, and in-vehicle devices 3 such as sensors 31 are directly connected by wire harnesses such as serial cables (direct wires). It is connected. For example, the individual ECU 2 acquires (receives) a signal (input signal) output from the sensor 31 and transmits a request signal generated based on the acquired input signal to the integrated ECU 6 . Based on the control signal transmitted from integrated ECU6, individual ECU2 performs drive control of the actuator 30 directly connected to self ECU. In this manner, the individual ECU 2 drives the in-vehicle device 3 such as the actuator 30 directly connected to the own ECU under the control of the integrated ECU 6 . The individual ECU 2 is a relay control ECU that functions as an in-vehicle relay device such as a gateway or Ethernet switch that relays communication between the plurality of in-vehicle devices 3 connected to the individual ECU 2 or communication between the in-vehicle device 3 and the integrated ECU 6. may The individual ECU 2 is a PLB (Power Lan Box) that functions not only as a relay for communication but also as a power distribution device that distributes and relays the power output from the power supply device 5 and supplies it to the in-vehicle device 3 connected to its own ECU. There may be.

The integrated ECU 6 generates and outputs control signals to the individual vehicle-mounted devices 3 based on the data from the vehicle-mounted device 3 relayed via the individual ECU 2, and is a central control device such as a vehicle computer. The integrated ECU 6 generates a control signal for controlling the actuator 30, which is the target of the request signal, based on information or data such as a request signal output (transmitted) from the individual ECU 2, and sends the generated control signal to the individual ECU 2. output (send) to A plurality of individual ECUs 2 are connected to the integrated ECU 6 via an in-vehicle network 4 , and the request signals transmitted from the individual ECUs 2 may conflict with each other in controlling the actuator 30 . On the other hand, the integrated ECU 6 may determine the priority of the competing controls in these request signals, and perform processing according to the priority to resolve the conflict of control over the actuator 30 .

The in-vehicle device 3 includes various sensors 31 such as a LiDAR (Light Detection and Ranging), a light sensor, a CMOS camera, an infrared sensor, switches such as a door SW (switch) and a lamp SW, a lamp, a door opening/closing device, and a motor device. etc. actuator 30 .

The external server 100 is a computer such as a server connected to a network outside the vehicle such as the Internet or a public network, and has a storage unit such as a RAM (Random Access Memory), a ROM (Read Only Memory), or a hard disk. The integrated ECU 6 is communicably connected to the external communication device 1 and communicates with the external server 100 connected via the external network via the external communication device 1. Alternatively, it may relay communication with the in-vehicle device 3 .

The vehicle-external communication device 1 includes a vehicle-external communication unit (not shown) and an input/output I/F (not shown) for communicating with the integrated ECU 6 . The external communication unit is a communication device for wireless communication using mobile communication protocols such as 4G, LTE (Long Term Evolution/registered trademark), 5G, and WiFi (registered trademark), and is connected to the external communication unit. Data is transmitted/received to/from the external server 100 via the antenna 11 . Communication between the external communication device 1 and the external server 100 is performed via an external network N such as a public line network or the Internet. The input/output I/F is a communication interface for serial communication with the integrated ECU 6, for example. The external communication device 1 and the integrated ECU 6 communicate with each other via an input/output I/F and a wire harness such as a serial cable connected to the input/output I/F. In the present embodiment, the external communication device 1 is separate from the integrated ECU 6, and these devices are communicably connected via an input/output I/F or the like, but the present invention is not limited to this. The external communication device 1 may be built in the integrated ECU 6 as one component of the integrated ECU 6 . Furthermore, the integrated ECU 6 and the external server 100 may cooperate or work together to function as a central control device in the vehicle C.

The integrated ECU 6 includes a control section 60 , a storage section 61 , an input/output I/F 62 and an in-vehicle communication section 63 . The control unit 60 is configured by a CPU (Central Processing Unit) or MPU (Micro Processing Unit) or the like, and reads and executes a program P (program product) and data stored in advance in the storage unit 61 to perform various functions. control processing, arithmetic processing, and the like. The control unit 60 is not limited to a software processing unit that performs software processing such as a CPU, but includes a hardware processing unit that performs various control processing and arithmetic processing by hardware processing such as FPGA, ASIC, or SOC. may be

The storage unit 61 is composed of a volatile memory element such as RAM (Random Access Memory) or a non-volatile memory element such as ROM (Read Only Memory), EEPROM (Electrically Erasable Programmable ROM), or flash memory, A program P (program product) and data to be referred to during processing are stored in advance. The program P (program product) stored in the storage unit 61 may be a program P (program product) read from a recording medium readable by the integrated ECU 6 . Alternatively, the program P (program product) may be downloaded from an external computer (not shown) connected to a communication network (not shown) and stored in the storage unit 61 .

The input/output I/F 62, like the input/output I/F of the external communication device 1, is a communication interface for serial communication, for example. The integrated ECU 6 is communicably connected to the external communication device 1 via an input/output I/F 62 and a wire harness such as a serial cable.

The in-vehicle communication unit 63 is an input/output interface that uses a communication protocol such as CAN (Control Area Network) or Ethernet (registered trademark). It communicates with the individual ECU 2 that is set.

As with the integrated ECU 6, the individual ECU 2 includes a control unit 20, a storage unit 21, an input/output I/F 22, an in-vehicle communication unit 23, and a semiconductor fuse 24 configured as, for example, an IPD (Intelligent Power Device). It is connected to the actuator 30 via the fuse 24 . That is, the individual ECU 2 and the actuator 30 are directly connected. The control unit 20, the storage unit 21, the input/output I/F 22, and the in-vehicle communication unit 23 of the separate ECU 2 may have the same configuration as the integrated ECU 6.

An in-vehicle device 3 such as a sensor 31 is directly connected to the input/output I/F 22 of the individual ECU 2 via a wire harness (direct wire) such as a serial cable.

A control signal output from the integrated ECU 6 is buffered (stored) in the storage unit 21 of the individual ECU 2 . A partial area in the storage unit 21 of the individual ECU 2 is reserved (allocated) in advance as a predetermined storage area (buffering area) for buffering the control signal output from the integrated ECU 6. good too.

The semiconductor fuse 24 of the individual ECU 2 is configured as an IPD (Intelligent Power Device) including, for example, an FET (Field effect transistor) or an IGBT (Insulated Gate Bipolar Transistor). The IPD may include a current sensor, detect a current value flowing through the wire 51 to which the semiconductor fuse 24 is connected, and output the detected current value to the control unit 20 . The semiconductor fuse 24 (IPD) supplies and cuts off electric power to the actuator 30 such as a lamp through the electric wire 51 .

The semiconductor fuse 24 functions as a semiconductor switch in the normal operation of supplying and cutting off power to the actuator 30, and is turned on or off based on the drive signal (gate signal) output from the control unit 20. Thereby, the driving of the actuator 30 connected by the electric wire 51 is controlled. Furthermore, the semiconductor fuse 24 functions as a protection device that cuts off the current when an overcurrent flows, for example. In this embodiment, the semiconductor fuse 24 is cut off when the value of the current (current value) flowing through the semiconductor fuse 24 is greater than or equal to the cutoff current threshold value transmitted from the integrated ECU 6 .

The semiconductor fuse 24 (IPD) and the control section 20 are connected by an internal bus or signal line. Alternatively, the semiconductor fuse 24 (IPD) and the control section 20 may be connected via the input/output I/F 22 . The control unit 20 acquires the current value of the electric wire 51 to which the semiconductor fuse 24 (IPD) is connected via the signal line or the like. Alternatively, the current sensor is provided separately from the semiconductor fuse 24 (IPD), and the control unit 20 detects the It may be one that acquires the current value that has been set. When acquiring the detected current value, the control unit 20 may AD-convert the current value.

The power supply device 5 is, for example, a lead battery that outputs a voltage of 12V (+B). Alternatively, the power supply device 5 may include a DCDC converter or a regulator that steps down the voltage output from a high voltage battery such as a lithium ion battery or an alternator to a predetermined voltage such as 12V. The power source device 5 and the individual ECU 2 are connected by a power harness or the like, and power is supplied from the power source device 5 to the individual ECU 2 via the power harness or the like.

By executing a program (program product) stored in the storage unit 21 of its own ECU, the individual ECU 2 receives a signal (input signal) output from the in-vehicle device 3 such as the sensor 31 connected to its own ECU. It acquires and outputs data (request signal) generated based on the signal (input signal) to the integrated ECU 6 . The individual ECU 2 acquires data (control signal) output from the integrated ECU 6, and transmits a signal (drive signal) generated based on the data (control signal) to the in-vehicle device 3 such as the actuator 30 connected to its own ECU. output to Alternatively, the individual ECU 2 performs drive control of the actuator 30 by performing on/off control of the semiconductor fuse 24 (IPD) to which the actuator 30 is connected according to the data (control signal) output from the integrated ECU 6. The control signal output from the integrated ECU 6 is temporarily buffered in a predetermined storage area (buffering area), read by the control unit 20 of the individual ECU 2, and converted into a drive signal for driving the actuator 30. can be anything.

The integrated ECU 6 configured in this manner and the plurality of individual ECUs 2 are communicably connected in a star-shaped network topology as shown in FIG. 1, for example. Further, adjacent individual ECUs 2 may be connected to form a loop-shaped network topology to enable two-way communication and achieve redundancy.

The integrated ECU 6 and the plurality of individual ECUs 2 are connected to the power supply device 5 by a power harness, and are supplied with electric power from the power supply device 5 . Electric power from the power supply device 5 is supplied (distributed) via the individual ECU 2 to the actuator 30 that is directly connected to the individual ECU 2 .

FIG. 3 is an explanatory diagram illustrating the flow (sequence) of processing by the individual ECU 2 and the integrated ECU 6. As shown in FIG. The individual ECU 2 detects a current value (S01). The separate ECU 2 outputs (transmits) the current value to the integrated ECU 6 (S02). The individual ECU 2 detects the current value of the wire 51 provided with the semiconductor fuse 24 by acquiring the detection value of the current sensor included in the IPD or the like that configures the semiconductor fuse 24 . The individual ECU 2 detects the current value at a predetermined cycle, and periodically outputs (transmits) the detected current value to the integrated ECU 6.

The integrated ECU 6 acquires (receives) the current value (S03). The integrated ECU 6 continuously waits for a current value transmitted from the individual ECU 2, acquires (receives) the current value each time it is transmitted, and stores it in a storage unit 61 of the integrated ECU 6. - 特許庁

The integrated ECU 6 calculates the wire temperature based on the current value (S04). For example, the integrated ECU 6 calculates the current wire temperature (the temperature of the wire 51 provided with the semiconductor fuse 24) by performing an integration process on a plurality of time-series current values periodically obtained from the individual ECUs 2. do. The integrated ECU 6 is provided with a semiconductor fuse 24 based on the difference between the integrated amount of heat generated based on the current value and the environmental temperature (amount of heat dissipation) determined in the space in which the semiconductor fuse 24 is provided in the individual ECU 2. The wire temperature is derived by calculating the temperature of the wire 51 (wire temperature). The process of calculating the wire temperature may be performed using a known processing method described in, for example, Japanese Patent Application Laid-Open No. 2015-23029 and Japanese Patent Application Laid-Open No. 2020-36461.

When the wire temperature is equal to or higher than the warning temperature threshold, the integrated ECU 6 derives a breaking current threshold based on the wire temperature (S05). The warning temperature threshold is a value predetermined according to the characteristics and type of the electric wire 51 provided with the semiconductor fuse 24, and is stored, for example, in the storage unit 61 of the integrated ECU 6. By referring to this, Integrated ECU6 acquires a warning temperature threshold. The integrated ECU 6 compares the calculated wire temperature with a warning temperature threshold to determine whether the wire temperature is equal to or higher than the warning temperature threshold. derive The breaking current threshold corresponds to (corresponds to) the temperature at which the semiconductor fuse 24 needs to be broken (breaking temperature threshold).

FIG. 4 is an explanatory diagram exemplifying the cut-off temperature threshold and the like. The explanatory diagram is shown by a graph in which the vertical axis is the wire temperature and the horizontal axis is the elapsed time. In the relationship between the warning temperature threshold (X1° C.) and the cut-off temperature threshold (X2° C.), the cut-off temperature threshold is higher than the warning temperature threshold (X2>X1). A value obtained by multiplying by a predetermined coefficient (K; for example, 1.2) greater than 1 may be used as the cutoff temperature threshold (X2=K·X1). When the wire temperature calculated from the current value reaches the warning temperature threshold, it is foreseen that the wire temperature will further rise and reach the cut-off temperature threshold, as shown in the graph illustrated in this embodiment. The integrated ECU 6 determines the current value (current value) when the warning temperature threshold is reached, and the material, length, and thickness of the electric wire 51 (the electric wire 51 provided with the semiconductor fuse 24) to be detected for the electric current value. A breaking current threshold corresponding to the breaking temperature threshold is derived based on characteristic parameters such as temperature.

The integrated ECU 6 outputs (transmits) the cut-off current threshold to the individual ECU 2 (S06). By outputting (transmitting) the breaking current threshold to the individual ECU 2, the integrated ECU 6 permits the individual ECU 2 to independently control the semiconductor fuse 24 according to the breaking current threshold. .

The individual ECU 2 acquires (receives) the breaking current threshold (S07). By acquiring (receiving) the breaking current threshold transmitted from the integrated ECU 6, the individual ECU 2 independently controls (breaking control) the semiconductor fuse 24 based on the acquired breaking current threshold. .

When the detected current value is greater than or equal to the cutoff current threshold, the individual ECU 2 cuts off the semiconductor fuse 24 (outputs a cutoff signal) (S08). The individual ECU 2 continues to periodically detect the current value, compares the current (latest) current value with the cutoff current threshold, and cuts off the semiconductor fuse 24 when the current value is equal to or greater than the cutoff current threshold. Therefore, for example, a cutoff signal is output to the semiconductor fuse 24 (IPD). As a result, the semiconductor fuse 24 is cut off (turned off), and the energization of the semiconductor fuse 24 is interrupted. The interrupted semiconductor fuse 24 is cooled by the atmosphere in the surrounding environment, and the temperatures of the semiconductor fuse 24 and the wire 51 are lowered. In breaking the semiconductor fuse 24, the individual ECU 2 outputs a break signal to the semiconductor fuse 24 (IPD), but the present invention is not limited to this. The semiconductor fuse 24 may be cut off by stopping the output of the signal. That is, in the present embodiment, the meaning of the output of the cutoff signal for cutting off the semiconductor fuse 24 is not only the output of the cutoff signal, but also the cutoff of the semiconductor fuse 24 by stopping the output of the driving signal such as duty. including doing.

The individual ECU 2 detects the current value (S09). The separate ECU 2 outputs (transmits) the current value to the integrated ECU 6 (S10). As described above, the individual ECU 2 continues to periodically detect the current value and output (transmit) it to the integrated ECU 6 . The current value is detected as 0 when the semiconductor fuse 24 is cut off.

The integrated ECU 6 acquires (receives) the current value (S11). The integrated ECU 6 calculates the wire temperature based on the current value (S12). When the semiconductor fuse 24 is cut off, the current value transmitted from the individual ECU 2 is 0, so that the integrated ECU 6 can grasp the period during which the semiconductor fuse 24 is cut off. The integrated ECU 6 may calculate the amount of heat released from the wire 51 according to the period during which the semiconductor fuse 24 is cut off, and calculate the current wire temperature.

The integrated ECU 6 outputs (transmits) a return signal to the individual ECU 2 when the electric wire temperature drops to a sufficiently low temperature (return temperature) (S13). A return temperature indicating that the wire temperature is sufficiently low is stored, for example, in the storage unit 61 of the integrated ECU 6, and the integrated ECU 6 can obtain the return temperature by referring to this. The integrated ECU 6 compares the current electric wire temperature with the restoration temperature, and outputs a restoration signal for restarting the energization of the semiconductor fuse 24 to the individual ECU 2 when the electric wire temperature becomes equal to or lower than the restoration temperature.

The individual ECU 2 acquires (receives) the return signal (S14). The individual ECU 2 resets the semiconductor fuse 24 (outputs a reset signal and resumes energization) according to the obtained reset signal (S15). After acquiring (receiving) the return signal from the integrated ECU 6 , the individual ECU 2 outputs the return signal to the semiconductor fuse 24 (IPD), restarts energization, and restores the semiconductor fuse 24 .

FIG. 5 is a flowchart illustrating processing of a control unit such as the integrated ECU 6. FIG. The integrated ECU 6 and the individual ECUs 2 routinely perform the following processes, for example, when the vehicle C is in the activated state (the IG switch is on). A series of processes of the integrated ECU 6 and the individual ECUs 2 are performed in association with each other. First, the processes of the integrated ECU 6 will be described, and then the processes of the individual ECUs 2 will be described.

The control unit 60 of the integrated ECU 6 acquires a current value (S101). The control unit 60 of the integrated ECU 6 acquires the current value (current value of the electric wire 51 provided with the semiconductor fuse 24) periodically transmitted from the individual ECU 2 .

The control unit 60 of the integrated ECU 6 calculates the wire temperature based on the current value (S102). The control unit 60 of the integrated ECU 6 calculates the electric wire temperature at the present time, for example, by integrating a plurality of time-series current values periodically acquired from the individual ECU 2 .

The control unit 60 of the integrated ECU 6 determines whether or not the electric wire temperature is equal to or higher than the warning temperature threshold (S103). The control unit 60 of the integrated ECU 6 acquires a predetermined warning temperature threshold according to the type of the electric wire 51, etc., and determines whether or not the electric wire temperature is equal to or higher than the warning temperature threshold. If the wire temperature is not equal to or higher than the warning temperature threshold (S103: NO), loop processing is performed to execute S101 again.

If the wire temperature is equal to or higher than the warning temperature threshold (S103: YES), the controller 60 of the integrated ECU 6 derives a breaking current threshold based on the wire temperature and the characteristic parameters of the wire 51 (S104). When the wire temperature is equal to or higher than the warning temperature threshold, the control unit 60 of the integrated ECU 6 determines that the wire temperature is expected to rise further, and derives the breaking current threshold. The control unit 60 of the integrated ECU 6 adjusts the breaking current based on characteristic parameters such as the wire temperature when the temperature exceeds the warning temperature threshold, the current value when the wire temperature is calculated, the material, thickness and length of the wire 51. Derive the threshold. The control unit 60 of the integrated ECU 6 calculates, for example, the ratio between the wire temperature when it reaches the alarm temperature threshold or higher and the cut-off temperature threshold predetermined according to the characteristics of the wire 51, and calculates the wire temperature. The breaking current threshold value may be calculated by correcting a value obtained by multiplying the actual current value by the ratio based on the characteristic parameter of the electric wire 51 . The breaking current threshold thus derived corresponds to (corresponds to) the temperature at which the semiconductor fuse 24 needs to be broken (breaking temperature threshold).

The control unit 60 of the integrated ECU 6 outputs the derived breaking current threshold to the individual ECU 2 (S105). After outputting the derived breaking current threshold to the individual ECU 2, the control unit 60 of the integrated ECU 6 may perform loop processing so as to execute the processing from S101 again.

The control unit 20 of the individual ECU 2 detects the current value (T101). The control unit 20 of the individual ECU 2 periodically acquires a current value detected by a current sensor included in an IPD that constitutes the semiconductor fuse 24, for example. The control unit 20 of the individual ECU 2 may store the current value detected by the current sensor in the storage unit 21 in association with the detection time.

The control unit 20 of the individual ECU 2 determines whether or not the breaking current threshold value has been acquired (T102). The control unit 20 of the individual ECU 2 constantly tries to acquire the breaking current threshold transmitted from the integrated ECU 6, and determines whether or not the breaking current threshold has been acquired.

When the breaking current threshold is acquired (T102: YES), the control unit 20 of the individual ECU 2 determines whether or not the current value detected immediately before is equal to or greater than the breaking current threshold (T103). The control unit 20 of the individual ECU 2 may store the acquired breaking current threshold value in the storage unit 21 in association with the acquired time point. The control unit 20 of the individual ECU 2 compares the breaking current threshold value with the previously detected current value (current value at the present time), and determines whether or not the current value is equal to or higher than the breaking current threshold value.

If the current value is greater than or equal to the cutoff current threshold (T103: YES), the control unit 20 of the individual ECU 2 performs cutoff processing (output cutoff instruction) to the semiconductor fuse 24 (T104). When the current value is equal to or greater than the cutoff current threshold, the control unit 20 of the individual ECU 2 instructs the semiconductor fuse 24 (IPD) to cut off output (output a cutoff signal), for example, thereby performing cutoff processing for the semiconductor fuse 24. conduct. As a result, the semiconductor fuse 24 is cut off (turned off), and the energization of the semiconductor fuse 24 is interrupted. As described above, even in the vehicle-mounted system S composed of the integrated ECU 6 and the individual ECU 2 that operates under the control of the integrated ECU 6, the direct control for cutting off the semiconductor fuse 24 is performed by the individual ECU 2 can run alone. As a result, even if a bottleneck or communication delay occurs in the communication between the individual ECU 2 and the integrated ECU 6, the semiconductor fuse 24 included in the individual ECU 2 can be reliably controlled with high immediate effect. .

If the breaking current threshold is not acquired (T102: NO), if the current value is not equal to or greater than the breaking current threshold (T103: NO), or after execution of S104, the control unit 20 of the individual ECU 2 sends the current value to the integrated ECU 6. Output (transmit) (T105). The control unit 20 of the individual ECU 2 may perform loop processing so as to execute the processing from T101 again after executing the processing of T105.

In the present embodiment, the controller 20 of the individual ECU 2 detects a current value, outputs the current value to the integrated ECU 6, acquires the breaking current threshold value, and cuts off the current. Not limited. The control unit 20 of the individual ECU 2 generates, for example, a plurality of sub-processes, and separates the process of detecting the current value and outputting the current value to the integrated ECU 6 and the process of acquiring the breaking current threshold and performing the breaking process. It may be processed and these processes may be performed in parallel (parallel processing by multi-process).

The embodiments disclosed this time are illustrative in all respects and should be considered not restrictive. The scope of the present invention is indicated by the scope of the claims rather than the above-described meaning, and is intended to include all modifications within the scope and meaning equivalent to the scope of the claims.

C vehicle
S In-vehicle system 100 External server 1 External communication device 11 Antenna 2 Individual ECU (first in-vehicle ECU)
20 control unit 21 storage unit 22 input/output I/F
23 in-vehicle communication unit 24 semiconductor fuse 3 in-vehicle device 30 actuator (ACT)
31 sensor 4 in-vehicle network 5 power supply device 51 electric wire 6 integrated ECU (second in-vehicle ECU)
60 control unit 61 storage unit 611 storage medium 62 input/output I/F
63 In-vehicle communication unit P program

Claims (10)

An in-vehicle system including a first in-vehicle ECU mounted in a vehicle and controlling a semiconductor fuse, and a second in-vehicle ECU communicably connected to the first in-vehicle ECU,
The first in-vehicle ECU
detecting a current value flowing through the semiconductor fuse;
outputting the detected current value to the second vehicle-mounted ECU;
The second vehicle-mounted ECU
Deriving a breaking current threshold based on the current value obtained from the first in-vehicle ECU,
outputting the derived breaking current threshold to the first vehicle-mounted ECU;
An in-vehicle system, wherein the first in-vehicle ECU cuts off the semiconductor fuse according to the cut-off current threshold obtained from the second in-vehicle ECU. The second vehicle-mounted ECU
deriving the temperature of the electric wire to which the semiconductor fuse is connected based on the current value obtained from the first in-vehicle ECU;
The in-vehicle system according to claim 1, wherein the breaking current threshold is derived when the temperature of the wire is equal to or higher than a predetermined warning temperature threshold. 3. The vehicle-mounted system according to claim 1, wherein the second vehicle-mounted ECU derives the breaking current threshold based on the temperature of the wire to which the semiconductor fuse is connected and the characteristic parameter of the wire. The in-vehicle system according to any one of claims 1 to 3, wherein the first in-vehicle ECU cuts off the semiconductor fuse when a current value flowing through the semiconductor fuse is equal to or greater than the cut-off current threshold. When the first in-vehicle ECU cuts off the semiconductor fuse according to the breaking current threshold, the second in-vehicle ECU restarts energization of the semiconductor fuse according to the temperature of the electric wire to which the semiconductor fuse is connected. The in-vehicle system according to any one of claims 1 to 4, wherein a return signal is output to said first in-vehicle ECU. An information processing method that causes a first computer that controls a semiconductor fuse and a second computer that is communicatively connected to the first computer to execute processing,
to the first computer;
detecting a current value flowing through the semiconductor fuse;
outputting the detected current value to the second computer;
to the second computer;
Deriving a breaking current threshold based on the current value obtained from the first computer,
Outputting the derived breaking current threshold to the first computer,
to the first computer;
An information processing method for executing a process of outputting a signal for breaking the semiconductor fuse according to the breaking current threshold obtained from the second computer. A program that causes a first computer that controls a semiconductor fuse and a second computer that is communicatively connected to the first computer to execute processing,
to the first computer;
detecting a current value flowing through the semiconductor fuse;
outputting the detected current value to the second computer;
to the second computer;
Deriving a breaking current threshold based on the current value obtained from the first computer,
Outputting the derived breaking current threshold to the first computer,
to the first computer;
A program for executing a process of outputting a signal for breaking the semiconductor fuse according to the breaking current threshold obtained from the second computer. A second vehicle-mounted ECU mounted on a vehicle and communicably connected to a first vehicle-mounted ECU that controls a semiconductor fuse,
A control unit that controls the first in-vehicle ECU,
The control unit
obtaining a current value flowing through the semiconductor fuse from the first in-vehicle ECU;
Deriving a breaking current threshold based on the obtained current value,
A second vehicle-mounted ECU that outputs the derived breaking current threshold to the first vehicle-mounted ECU to cause the first vehicle-mounted ECU to break the semiconductor fuse according to the breaking current threshold. A computer communicably connected to the first in-vehicle ECU that controls the semiconductor fuse,
obtaining a current value flowing through the semiconductor fuse from the first in-vehicle ECU;
Deriving a breaking current threshold based on the obtained current value,
and outputting the derived breaking current threshold to the first vehicle-mounted ECU to cause the first vehicle-mounted ECU to break the semiconductor fuse according to the breaking current threshold. A computer communicably connected to the first in-vehicle ECU that controls the semiconductor fuse,
obtaining a current value flowing through the semiconductor fuse from the first in-vehicle ECU;
Deriving a breaking current threshold based on the obtained current value,
A program for causing the first in-vehicle ECU to cut off the semiconductor fuse according to the cut-off current threshold by outputting the derived cut-off current threshold to the first in-vehicle ECU.

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