Vehicle-mounted communication system, control device, and electric device

Abstract

This vehicle-mounted communication system includes a first control device and a plurality of first electric devices. The first control device includes a first power supply unit that outputs electric power, a plurality of first communication units that respectively correspond to the plurality of first electric devices, a plurality of first communication paths that respectively correspond to the plurality of first communication units, and a first priority determination unit that determines a first priority for supplying the electric power from the first power supply unit to the plurality of first electric devices. The first priority determination unit transmits a first transmission request from the plurality of first communication units to the plurality of electric devices via the plurality of first communication paths, each of the plurality of first electric devices transmits, in response to the first transmission request, information indicating the degree of importance and required electric power of this first electric device to the first control device via the first communication path, and the first priority determination unit determines the first priority on the basis of the information indicating the degree of importance and required electric power and received from each of the plurality of first electric devices.

Description

In-vehicle communication systems, control devices and electrical devices

[0001] This disclosure relates to an in-vehicle communication system, a control device, and an electrical device. This application claims priority to Japanese Application No. 2022-171949, filed on October 27, 2022, and incorporates by reference all of the contents of said Japanese application.

[0002] In vehicles such as automobiles, various on-board electrical devices (e.g., cameras, sensors, and car navigation systems) are supplied with power from an on-board battery. For example, in a plug-in hybrid electric vehicle (PHEV) or an electric vehicle (EV), the output voltage of a high-voltage battery for driving a motor is converted to an appropriate voltage by a power conversion device and supplied to the electrical devices inside the vehicle.

[0003] Japanese Patent Application Laid-Open No. 2003-144993 discloses a data communication system that determines whether or not to supply power, taking into consideration the supply capacity of the power supplier and the capacity of the power receiver.

[0004] Japanese Patent Application Publication No. 10-154964

[0005] An in-vehicle communication system according to one aspect of the present disclosure is an in-vehicle communication system including a first control device and a plurality of first electrical devices, wherein the first control device includes a first power supply unit that outputs electric power, a plurality of first communication units corresponding to each of the plurality of first electrical devices, a plurality of first communication paths corresponding to each of the plurality of first communication units, and a first priority determination unit that determines a first priority for supplying electric power from the first power supply unit to the plurality of first electrical devices, wherein the first priority determination unit transmits a first transmission request from the plurality of first communication units to each of the plurality of first electrical devices via the plurality of first communication paths, and each of the plurality of first electrical devices transmits information representing the importance and required power of the first electrical device to the first control device via the first communication path in response to the first transmission request, and the first priority determination unit determines the first priority based on the information representing the importance and required power received from the plurality of first electrical devices.

[0006] FIG. 1 is a block diagram showing a configuration of an in-vehicle communication system according to a first embodiment of the present disclosure. FIG. 2 is a block diagram showing a configuration of a priority determination unit shown in FIG. 1. FIG. 3 is a block diagram showing a configuration of a PoDL (Power over Data Line) unit shown in FIG. 1. FIG. 4 is a block diagram showing a configuration of a control unit of an electric device shown in FIG. 1. FIG. 5 is a flowchart showing processing executed by the control device shown in FIG. 1. FIG. 6 is a flowchart showing processing executed by the electric device shown in FIG. 1. FIG. 7 is a flowchart showing processing executed by a control device according to a first modified example. FIG. 8 is a block diagram showing a configuration of an in-vehicle communication system according to a second embodiment. FIG. 9 is a block diagram showing a configuration of a priority determination unit of a second control device shown in FIG. 8. FIG. 10 is a block diagram showing a configuration of a control unit of an electric device connected to the first control unit and the second control unit shown in FIG. 8. FIG. 11 is a flowchart showing processing executed by the first control device shown in FIG. 8. FIG. 12 is a flowchart showing processing executed by the second control device shown in FIG. 8. FIG. 13 is a flowchart showing processing executed by an electric device according to a second modified example.

[0007] In a vehicle, electrical devices related to the basic functions of running, turning, and stopping are relatively important, and power must be supplied to them with priority over other electrical devices that are relatively less important. However, the data communication system disclosed in Patent Document 1 does not take this into consideration.

[0008] Therefore, the present disclosure aims to provide an in-vehicle communication system, a control device, and an electrical device that can supply power preferentially to electrical devices having specific functions based on the importance of each electrical device among multiple electrical devices installed in a vehicle.

[0009] [Effects of the Present Disclosure] According to the present disclosure, it is possible to provide an in-vehicle communication system, a control device, and an electrical device that can supply power preferentially to electrical devices having specific functions based on the importance of each electrical device among multiple electrical devices installed in a vehicle.

[0010] [Description of Embodiments of the Present Disclosure] The contents of the embodiments of the present disclosure will be listed and described below. At least some of the embodiments described below may be combined in any combination.

[0011] (1) A first aspect of the present disclosure provides an in-vehicle communication system including a first control device and a plurality of first electric devices, wherein the first control device includes a first power supply unit that outputs electric power, a plurality of first communication units corresponding to each of the plurality of first electric devices, a plurality of first communication paths corresponding to each of the plurality of first communication units, and a first priority determination unit that determines a first priority for supplying electric power from the first power supply unit to the plurality of first electric devices, wherein the first priority determination unit transmits first transmission requests from the plurality of first communication units to each of the plurality of first electric devices via the plurality of first communication paths, and each of the plurality of first electric devices transmits information representing the importance and power requirements of the first electric device to the first control device via the first communication path in response to the first transmission request, and the first priority determination unit determines the first priority based on the information representing the importance and power requirements received from the plurality of first electric devices. This allows electric devices having specific functions to be supplied with electric power preferentially from the plurality of electric devices mounted on the vehicle based on the importance of each electric device.

[0012] (2) In the above (1), when the first priority determination unit transmits the first transmission request, the first power supply unit can supply communication power necessary for each of the first electric devices to communicate with the first control device via the first communication paths, thereby reducing unnecessary power consumption.

[0013] (3) In the above (1) or (2), the first control device may further include at least one superimposing unit of the multiple first communication units. The superimposing unit may generate a superimposed signal by superimposing a communication signal output from the first communication unit on power supplied from the first power supply unit, and output the superimposed signal to a first communication path corresponding to the first communication unit that output the communication signal. The superimposing unit may also separate a signal including information indicating importance and required power from a transmission signal transmitted from the first electric device via the first communication path, and output the separated information to the first priority determination unit via the first communication unit corresponding to the first electric device that output the transmission signal. This allows power to be superimposed on the communication line transmitting the communication signal and supplied to the electric device. Therefore, the number of electrical wirings can be reduced.

[0014] (4) In the above (3), each of the plurality of first electric devices may include a separator that separates a signal including the first transmission request from a superimposed signal transmitted via the first communication path corresponding to the first electric device, and a communication unit that transmits information representing the importance and required power of the first electric device to the first control device via the first communication path in response to the first transmission request separated by the separator. This allows the first control device to receive information representing the importance and required power of each of the plurality of first electric devices and determine the first priority.

[0015] (5) In the above (4), the separator may further separate power from the superimposed signal transmitted via the first communication path corresponding to the first electric device, and each of the first electric devices may further include a power receiving unit that initially supplies the power separated by the separator to the communication unit. This enables the first electric device to transmit information indicating the importance and required power in response to a transmission request from the first control device.

[0016] (6) In any one of (1) to (5) above, the first priority determination unit may change the first priority depending on the state of the vehicle in which the in-vehicle communication system is installed. This allows an appropriate priority to be determined depending on the state of the vehicle. The importance of each electrical device installed in the vehicle changes depending on the state of the vehicle. Therefore, power can be supplied preferentially to an electrical device having a specific function depending on the state of the vehicle.

[0017] (7) In any one of (1) to (6) above, the in-vehicle communication system may further include a second control device and a plurality of second electric devices, at least one of the plurality of first electric devices being a specific electric device, and the second control device may include a second power supply unit that outputs electric power, a plurality of second communication units corresponding to each of the plurality of second electric devices and the specific electric device, a plurality of second communication paths corresponding to each of the plurality of second communication units, and a second priority determination unit that determines a second priority for supplying electric power from the second power supply unit to the plurality of second electric devices and the specific electric device, and the second priority determination unit may be The second control unit may transmit a second transmission request to each of the plurality of second electric devices via the plurality of second communication paths, and each of the plurality of second electric devices may transmit, in response to the second transmission request, information representing the importance and power requirements of the second electric device to the second control unit via the second communication path, and the second priority determination unit may determine the second priority based on the information representing the importance and power requirements received from the plurality of second electric devices, and in response to a reduction in power supplied from the first power supply unit to the specific electric device, the second priority determination unit may change the second priority so that power is supplied from the second power supply unit to the specific electric device. This makes it possible to supply power to the specific electric device and maintain its function even when the power supplied from the first control unit to the specific electric device is reduced.

[0018] (8) In the above (7), the first priority determination unit may notify the second priority determination unit of information indicating that the power supplied from the first power supply unit to the specific electrical device will be reduced. This allows the second control unit to efficiently start supplying power to the specific electrical device when the power supplied from the first control unit to the specific electrical device is reduced.

[0019] (9) In the above (7), the specific electrical device may notify the second priority determination unit of information indicating that the power supplied from the first power supply unit to the specific electrical device will be reduced. This allows the second control device to efficiently start supplying power to the specific electrical device when the power supplied from the first control device to the specific electrical device is reduced.

[0020] (10) In the above (8) or (9), the information indicating that power will be reduced may include information indicating the importance and power requirements of the specific electrical device, thereby allowing the second control device to quickly change the priority so that power can be supplied to the specific electrical device.

[0021] (11) A control device according to a second aspect of the present disclosure is a control device mounted on a vehicle, including a power supply unit that outputs electric power, a plurality of communication units, and a priority determination unit that determines a priority for supplying electric power from the power supply unit to a plurality of electric devices mounted on the vehicle corresponding to each of the plurality of communication units via a plurality of communication paths corresponding to each of the plurality of communication units, wherein the priority determination unit transmits a transmission request to each of the plurality of electric devices from the plurality of communication units via the plurality of communication paths, and receives, in response to the transmission request, information indicating the importance and power requirements of the electric device from each of the plurality of electric devices via the communication paths, and the priority determination unit determines the priority based on the information indicating the importance and power requirements received from the plurality of electric devices. This allows power to be supplied from the control device to the plurality of electric devices mounted on the vehicle based on the importance of each electric device.

[0022] (12) A control device according to a third aspect of the present disclosure is a control device mounted on a vehicle, including a power supply unit that outputs electric power, multiple communication units, and a priority determination unit that determines priorities for supplying electric power from the power supply unit to multiple electric devices mounted on the vehicle via multiple communication paths corresponding to the multiple communication units. At least one of the multiple electric devices is designated as a specific electric device. The priority determination unit transmits transmission requests from the multiple communication units via the multiple communication paths to electric devices other than the specific electric device. In response to the transmission requests, the priority determination unit receives information indicating the importance and power requirements of the electric devices from the electric devices other than the specific electric device via the communication paths. The priority determination unit determines the priority based on the information indicating the importance and power requirements received from the electric devices other than the specific electric device. In response to a reduction in power supplied to the specific electric device from an on-board device other than the control device, the priority determination unit changes the priority so that power is supplied to the specific electric device from the power supply unit. This enables power to be supplied to the specific electric device, and the specific electric device can maintain its function, even when power supplied to the specific electric device from an on-board device other than the control device is reduced.

[0023] (13) According to a fourth aspect of the present disclosure, an electric device is mounted on a vehicle and includes: a separator that separates a communication signal from a superimposed signal on which power and the communication signal are superimposed and that is transmitted from a control device mounted on the vehicle via a communication path; and a communicator that transmits information indicating the importance and power requirements of the electric device to the control device via the communication path in response to a transmission request included in the communication signal. This allows the control device to supply power to multiple electric devices mounted on the vehicle based on the importance of each electric device.

[0024] (14) In the above (13), the separator may further include a power receiving unit that further separates power from the superimposed signal transmitted through the communication path and first supplies the power separated by the separator to the communication unit, thereby enabling the electrical device to transmit information indicating importance and required power.

[0025] (15) In the above (14), the electric device may further include a separation unit separate from the separation unit that receives power from an on-board device separate from the control device via a path separate from the communication path in response to a reduction in power supplied from the control device, and the separate separation unit may separate power from a superimposed signal in which the power supplied from the on-board device via the path separate from the communication signal and the communication signal are superimposed, and output the power to the power receiving unit. This makes it possible to supply power to the electric device even when the power supplied from the control device to the electric device is reduced, and the electric device can maintain its function.

[0026] [Details of the embodiments of the present disclosure] In the following embodiments, the same components are denoted by the same reference numerals, and their names and functions are also the same. Therefore, detailed descriptions thereof will not be repeated.

[0027] (First Embodiment) (Overall Configuration) Referring to FIG. 1 , an in-vehicle communication system 100 according to a first embodiment of the present disclosure includes a control device 102 and electric devices 104, 106, and 108. The in-vehicle communication system 100 is mounted on a vehicle (not shown). The control device 102 is, for example, a C-ECU (Central-Electronic Control Unit). Each of the electric devices 104, 106, and 108 is an in-vehicle camera, a sensor, a car navigation system, or the like, and is a target to which power is supplied from the control device 102. The control device 102 and the electric devices 104, 106, and 108 are communicatively connected via communication lines 140, 142, and 144, respectively. Each communication line constitutes a communication path for connecting the electric devices and a control unit. Note that, although three electric devices are shown in FIG. 1 , this is not a limitation. The control device 102 may be connected to two electric devices so as to be able to supply power to them. Additionally, the control device 102 may be connected to supply power to four or more electrical devices.

[0028] (Configuration of Control Device) The control device 102 includes a priority determination unit 110, a power supply control unit 112, a power supply unit 114, data I / O units 116, 118, and 120, and PoDL units 122, 124, and 126. As described below, each data I / O unit and its corresponding PoDL unit constitute a communication unit through which the control device 102 communicates with each electrical device. Referring to FIG. 2 , the priority determination unit 110 includes a CPU (Central Processing Unit) 150 and a memory 152. The CPU 150 controls the memory 152. The memory 152 is, for example, a rewritable nonvolatile semiconductor memory and stores a computer program (hereinafter simply referred to as a program) executed by the CPU 150. The CPU 150 stores the results of the executed processing in the memory 152 as appropriate. CPU 150 outputs and stores data input from data I / O units 116, 118, and 120 in memory 152. CPU 150 also reads and outputs data from memory 152 to be output from priority determination unit 110 to power supply control unit 112 and data I / O units 116, 118, and 120.

[0029] As described below, the priority determination unit 110 determines the priority of supplying power from the control device 102 to the electrical devices 104, 106, and 108, and outputs information indicating the determined priority (hereinafter referred to as priority information) to the power supply control unit 112. The power supply control unit 112 outputs information (hereinafter referred to as output power information) indicating the value of power to be output from the multiple ports of the power supply unit 114 to the power supply unit 114 in accordance with the priority information input from the priority determination unit 110. The power supply unit 114 outputs the indicated amount of power (i.e., DC power) from each output port in accordance with the output power information input from the power supply control unit 112. The three output ports of the power supply unit 114 are connected to the PoDL units 122, 124, and 126, respectively, and the output power of the power supply unit 114 is input to the PoDL units 122, 124, and 126. The power output by the power supply unit 114 is generated from external power supplied from outside the control device 102 (power necessary for the operation of the control device 102, for example, power obtained by converting the voltage of an on-board battery (not shown) to a predetermined voltage).

[0030] The priority determination unit 110 acquires predetermined information for determining the above-described priority from the electrical devices 104, 106, and 108. To do so, the priority determination unit 110 outputs an instruction requesting the predetermined information (e.g., predetermined code data, hereinafter referred to as a transmission request) via the data I / O units 116, 118, and 120. The predetermined information represents the function and power requirements of each electrical device. The power requirements refer to the power required to operate the electrical device. The power requirements are, for example, the rated power consumption of each electrical device and can be acquired from the specifications or instruction manuals of each electrical device. The power requirements may be determined from the power consumption measured while each electrical device is operating. The data I / O units 116, 118, and 120 output a communication signal corresponding to the transmission request input from the priority determination unit 110. The data I / O units 116, 118 and 120 are connected to the PoDL units 122, 124 and 126, respectively, and communication signals (i.e., transmission requests) output from the data I / O units 116, 118 and 120 are input to the PoDL units 122, 124 and 126.

[0031] Each of the PoDL units 122, 124, and 126 functions as a signal superposition unit. That is, the PoDL unit 122 generates a signal (hereinafter referred to as a superposed signal) by superposing a communication signal (e.g., a transmission request) input from the data I / O unit 116 on DC power input from the power supply unit 114, and outputs the signal to the communication line 140. Similarly, the PoDL unit 124 superimposes a communication signal (e.g., a transmission request) input from the data I / O unit 118 on DC power input from the power supply unit 114, and outputs the superposed signal to the communication line 142. The PoDL unit 126 superimposes a communication signal (e.g., a transmission request) input from the data I / O unit 120 on DC power input from the power supply unit 114, and outputs the superposed signal to the communication line 144.

[0032] Each of the PoDL units 122, 124, and 126 includes, for example, a bias tee. For example, referring to FIG. 3 , the PoDL unit 122 includes a capacitor C1 disposed between terminals T1 and T3 and an inductor L1 disposed between terminals T2 and T3. When a communication signal (i.e., an AC signal) output from the data I / O unit 116 is input to terminal T1 and DC power (i.e., a DC signal) output from the power supply unit 114 is input to terminal T2, a signal in which the AC signal is superimposed on a DC component is output from terminal T3. Each of the PoDL units 122, 124, and 126 is not limited to a circuit using a capacitor and an inductor, but may also be configured as a distributed constant circuit using stubs. The communication lines 140, 142, and 144 are realized, for example, by a coaxial cable or a twisted-pair cable for transmitting differential signals.

[0033] Each of the PoDL units 122, 124, and 126 also functions as a signal separator. That is, the PoDL unit 122 separates AC components from a communication signal input via the communication line 140 (i.e., a signal biased with DC power from the power supply unit 114) and outputs the separated AC components to the data I / O unit 116. Referring to FIG. 3 , when a communication signal input to the PoDL unit 122 via the communication line 140 is input to terminal T3, an AC component is output from terminal T1. The output from terminal T1 is input to the data I / O unit 116, which generates digital data and outputs it to the priority determination unit 110. Similarly, the PoDL unit 124 separates AC components from a communication signal input via the communication line 142 and outputs it to the data I / O unit 118. The data I / O unit 118 generates digital data and outputs it to the priority determination unit 110. The PoDL unit 126 separates AC components from the communication signal input via the communication line 144 and outputs the separated AC components to the data I / O unit 120. The data I / O unit 120 generates digital data and outputs the digital data to the priority determination unit 110. This allows the priority determination unit 110 to receive data transmitted from the electrical devices 104, 106, and 108.

[0034] The PoDL unit 122 is connected to the PoDL unit 136 of the electric device 104 via a communication line 140, and the superimposed signal output from the PoDL unit 122 is transmitted to the PoDL unit 136 via the communication line 140. Similarly, the PoDL unit 124 is connected to the PoDL unit of the electric device 106 via a communication line 142, and the superimposed signal output from the PoDL unit 124 is transmitted to the PoDL unit of the electric device 106 via the communication line 142. The PoDL unit 126 is connected to the PoDL unit of the electric device 108 via a communication line 144, and the superimposed signal output from the PoDL unit 126 is transmitted to the PoDL unit of the electric device 108 via the communication line 144.

[0035] (Configuration of Electrical Device) Electrical device 104 includes a control unit 130, a power receiving unit 132, a data I / O unit 134, a PoDL unit 136, a functional unit 138, and a switch 139. Functional unit 138 is an element for realizing the functions of electrical device 104. Electrical devices 106 and 108 also include the same elements as electrical device 104. However, the functional units that are elements for realizing the functions of electrical devices 106 and 108 may differ from functional unit 138 of electrical device 104.

[0036] The PoDL unit 136 functions as a separator, similar to the PoDL unit 122. That is, the PoDL unit 136 separates an input signal (i.e., a signal biased with DC power from the power supply unit 114) into an AC component and a DC component and outputs the separated signals. The separated AC component is input to the data I / O unit 134, and the separated DC component is input to the power receiving unit 132. The PoDL unit 136 has a configuration similar to the PoDL unit 122. The PoDL unit 136 includes, for example, a bias tee. When a superimposed signal input to the PoDL unit 136 from the communication line 140 is input to terminal T3 (see FIG. 3 ), an AC component is output from terminal T1, and a DC component is output from terminal T2. The output from terminal T1 is input to the data I / O unit 134, and the output from terminal T2 is input to the power receiving unit 132.

[0037] The power receiving unit 132 receives the DC component separated by the PoDL unit 136, i.e., DC power, and first supplies the received DC power to the data I / O unit 134 and the control unit 130. This allows the control unit 130 and the data I / O unit 134 to function, and as described below, the data I / O unit 134 and the control unit 130 can receive communication signals transmitted via the communication line 140. The control unit 130 and the data I / O unit 134 can also output communication signals to the communication line 140. If the power supplied from the PoDL unit 136 is sufficient to perform the function of the electric device 104, the power receiving unit 132 also supplies power to the functional unit 138, which is an element for performing that function. As described below, as a result of this communication, the control unit 130 controls the on / off of the switch 139, thereby controlling the power supply from the power receiving unit 132 to the functional unit 138.

[0038] The data I / O unit 134 receives the AC component separated by the PoDL unit 136, i.e., the communication signal, generates digital data from the input communication signal, and outputs the digital data to the control unit 130. The data I / O unit 134 operates according to the same communication specifications as the data I / O unit 116.

[0039] 4 , control unit 130 includes a CPU 160 and a memory 162. CPU 160 controls memory 162. Memory 162 is, for example, a rewritable nonvolatile semiconductor memory, and stores programs executed by CPU 160. CPU 160 stores the results of the executed processing in memory 162 as appropriate. CPU 160 outputs data input from data I / O unit 134 to memory 162 for storage. CPU 160 also reads data to be output to data I / O unit 134 from memory 162 and outputs the data to data I / O unit 134. If the data input from data I / O unit 134 to CPU 160 is an instruction to control unit 130 (for example, the above-mentioned transmission request), CPU 160 executes the instructed processing and outputs the result to data I / O unit 134. For example, the CPU 160 reads information (i.e., predetermined information) representing the functions and power requirements of the electric device 104 stored in the memory 162 and outputs it to the data I / O unit 134. As a result, the processing result (i.e., predetermined information) is transmitted to the control device 102 via the communication line 140 and received by the priority determination unit 110. As will be described later, the reason for transmitting the information representing the functions is to determine the importance of the functions. For example, in a vehicle, the importance of electric devices related to the basic functions of driving, turning, and stopping is relatively high. That is, the information representing the functions is used as an example of information representing the importance.

[0040] The function of an electrical device refers to the intended function of the electrical device. For example, an imaging function for an in-vehicle camera, a sensing function for a sensor, a navigation function for a car navigation system, and an entertainment function for an entertainment device. Therefore, information representing the function can be determined in advance by classifying electrical devices that can be installed in a vehicle according to their functions. For example, a predetermined code can be assigned to each in-vehicle camera, sensor, and car navigation system. Furthermore, even if electrical devices have the same function, different codes can be assigned to electrical devices used for different purposes according to their uses (i.e., their subdivided functions). For example, different codes can be assigned to a forward monitoring camera, a rear monitoring camera, an around-view monitor camera, and an in-vehicle camera.

[0041] Each of the electric devices 106 and 108 operates in the same manner as the electric device 104. That is, each of the electric devices 106 and 108 receives a transmission request from the priority determination unit 110 of the control device 102 and transmits information indicating the function and power requirements of each of the electric devices 106 and 108 (i.e., predetermined information) to the control device 102. The predetermined information is received by the priority determination unit 110.

[0042] (Operation of Control Device) The operation of the control device 102 will be described with reference to Fig. 5. The process shown in Fig. 5 is realized, for example, by the CPU 150 of the priority determination unit 110 shown in Fig. 2 reading and executing a corresponding program from the memory 152. The program is read, for example, when the start button of the vehicle equipped with the in-vehicle communication system 100 is turned on.

[0043] In step 300, the CPU 150 supplies communication power to each of the electric devices 104, 106, and 108 to which power is to be supplied from the control device 102. Thereafter, control proceeds to step 302. Specifically, the CPU 150 instructs the power supply control unit 112 to supply communication power from the power supply unit 114. In response to this, the power supply control unit 112 instructs the power supply unit 114 to output communication power from the output port, and the power supply unit 114 outputs the communication power from the output port in accordance with the instruction of the power supply control unit 112. As described above, the power output from the power supply unit 114 is output as a superimposed signal by the PoDL units 122, 124, and 126 to the communication lines 140, 142, and 144. The superimposed signals transmitted via the communication lines 140, 142, and 144 are input to the PoDL units of the electric devices 104, 106, and 108, and the DC components are separated and input to the power receiving units. As a result, power is first supplied from the power receiving unit to the data I / O unit and the control unit, enabling the data I / O unit and the control unit to operate. The communication power is the power that each of the electric devices 104, 106, and 108 requires to communicate with the control device 102, and is less than the power required to realize its function. The communication power can be calculated from the communication function of each electric device installed in the vehicle. For example, the maximum value of the calculated values ​​for the multiple electric devices may be set as the communication power and stored in memory 152 in advance.

[0044] In step 302, CPU 150 requests information indicating its own functions and power requirements from each of electric devices 104, 106, and 108, which are to receive power from control device 102. Control then proceeds to step 304. Specifically, CPU 150 outputs a transmission request to data I / O units 116, 118, and 120, as described above. As a result, PoDL units 122, 124, and 126 output superimposed signals, in which the communication signals supplied from data I / O units 116, 118, and 120 are superimposed on the power supplied from power supply unit 114, to communication lines 140, 142, and 144, as described above. The superimposed signals transmitted via communication lines 140, 142, and 144 are input to the PoDL units of electric devices 104, 106, and 108, where they are separated into DC and AC components. The DC component is input to the power receiving unit, and power is supplied from the power receiving unit to the data I / O unit and the control unit, maintaining the data I / O unit and the control unit in an operable state. The AC component is input to the data I / O unit, converted into digital data, and input to the control unit. This allows the control unit of each of the electrical devices 104, 106, and 108 to receive the transmission request transmitted from the control device 102.

[0045] In step 304, the CPU 150 determines whether or not reply information has been received in response to the transmission request sent in step 302. The reply information is information indicating the function and power requirements (i.e., predetermined information). If it is determined that the reply information has been received, control proceeds to step 306. If not, control proceeds to step 308.

[0046] In step 306, the CPU 150 stores the data received in step 304 (i.e., the reply information) in the memory 152. Thereafter, control proceeds to step 308.

[0047] In step 308, the CPU 150 determines whether or not reply information has been received from all of the electric devices 104, 106, and 108 to which power is supplied from the control device 102. If it is determined that reply information has been received, control proceeds to step 310. If not, control returns to step 304 to wait for reply information from the electric devices.

[0048] In step 310, the CPU 150 reads the response information (i.e., information representing the functions and power requirements) stored in the memory 152 in step 306 and determines the priority of supplying power from the control device 102 based on the functions and power requirements. The priority includes an order of precedence. For example, if the response information indicates that the electric device 104 is an object detection camera, the electric device 106 is a car navigation system, and the electric device 108 is an entertainment device, the CPU 150 can determine the priority (i.e., the priority) so that the electric device 104 has the highest priority, followed by the electric devices 104, 106, and 108 in descending order. For example, if the sum of the power requirements of the electric devices 104, 106, and 108 exceeds the maximum output of the power supply unit 114, power is supplied to the electric devices 104, 106, and 108 in that order within the range of the maximum output of the power supply unit 114.

[0049] In step 312, CPU 150 starts supplying power from power supply unit 114 to electric devices 104, 106, and 108 in accordance with the priority determined in step 310. Specifically, as described above, CPU 150 outputs priority information to power supply control unit 112. As a result, power supply control unit 112 outputs output power information to power supply unit 114 in accordance with the priority information input from priority determination unit 110. Power supply unit 114 outputs power (i.e., DC power) from each output port in accordance with the output power information input from power supply control unit 112. The output power of power supply unit 114 is input to PoDL units 122, 124, and 126 and supplied to electric devices 104, 106, and 108 via communication lines 140, 142, and 144.

[0050] In step 314, CPU 150 determines whether data has been received from the electrical device to which it supplies power. If it is determined that data has been received, control proceeds to step 316. If not, control proceeds to step 318.

[0051] In step 316, CPU 150 outputs the data received in step 314 to the corresponding device. Control then proceeds to step 318. For example, if the data is from an object detection camera, the data is output to an autonomous driving ECU (Electronic Control Unit). The autonomous driving ECU analyzes the output data from the object detection camera to understand the situation around the vehicle and controls mechanisms related to autonomous driving (mechanisms such as the engine, transmission, steering, and brakes).

[0052] In step 318, the CPU 150 determines whether an end command has been received. If it is determined that an end command has been received, the program ends. If not, control proceeds to step 314. The end command is issued, for example, by turning off the start button of the vehicle in which the in-vehicle communication system 100 is installed.

[0053] (Operation of Electric Devices) The operations of electric devices 104, 106, and 108 will be described. The operations of electric devices 104, 106, and 108 are the same. Here, the operation of electric device 104 will be described with reference to FIG. 6. The processing shown in FIG. 6 is realized by CPU 160 of control unit 130 shown in FIG. 4 reading and executing a corresponding program from memory 162. The program is read when power for communication is supplied to electric device 104 from power supply unit 114 of control device 102 in step 300 shown in FIG. 5, and control unit 130 becomes operable.

[0054] In step 400, the CPU 160 determines whether or not a transmission request has been received. If it is determined that a transmission request has been received, control proceeds to step 402. If not, step 400 is repeated.

[0055] In step 402, the CPU 160 transmits information indicating the functions and power requirements of the electric device 104 to the control device 102. Specifically, as described above, the CPU 160 reads the information indicating the functions and power requirements of the electric device 104 from the memory 162 and outputs it to the data I / O unit 134. As a result, the information indicating the functions and power requirements is transmitted as reply information in response to a transmission request from the control device 102 (specifically, the priority determination unit 110). Thereafter, the program ends.

[0056] After transmitting the reply information to the control device 102, the electric device 104 executes its own function when it receives from the control device 102 power sufficient to execute the function of the electric device 104 (i.e., power corresponding to the required power). That is, the CPU 160 of the control unit 130 turns on the switch 139, which is initially off, and power for executing the function of the electric device 104 is supplied from the power receiving unit 132 to the function unit 138. On the other hand, if the priority of the electric device 104 is low and power is not supplied to the electric device 104 from the control device 102 after transmitting the reply information to the control device 102, the electric device 104 cannot be started. That is, the switch 139 remains off.

[0057] As described above, it is possible to determine priorities for multiple electrical devices installed in a vehicle and supply power based on the determined priorities. For example, if priorities are determined according to the importance of each electrical device, power can be supplied preferentially to electrical devices having specific functions based on the importance of each electrical device.

[0058] As described above, when power is not being supplied to each electric device, the control device 102 supplies communication power that enables each electric device to communicate with the control device 102. This makes it possible to reduce unnecessary power consumption.

[0059] As described above, the control device 102 includes PoDL units 122, 124, and 126 that superimpose DC power from the power supply unit 114 on communication signals from the data I / O units 116, 118, and 120 and output the superimposed signals. This allows the control device 102 to superimpose DC power onto the communication lines 140, 142, and 144 that transmit the communication signals and supply the superimposed DC power to the electrical devices 104, 106, and 108. This allows the number of electrical wiring lines to be reduced.

[0060] As described above, each electrical device includes a PoDL unit having a function of separating a communication signal from a superimposed signal transmitted via a communication line, and a data I / O unit having a communication function of transmitting information indicating its own importance (specifically, function) and required power in response to the separated transmission request to the control device 102 via the communication line. This allows the control device 102 to receive information indicating the importance (specifically, function) and required power of each electrical device from multiple electrical devices, thereby enabling it to determine priority.

[0061] As described above, the PoDL unit of each electric device separates DC power from the superimposed signal transmitted over the communication line, and each electric device includes a power receiving unit that first supplies the separated DC power to a data I / O unit having a communication function. This enables each electric device to transmit information indicating the importance (specifically, function) and power requirements of each electric device in response to a transmission request from the control device 102.

[0062] In the above description, the program shown in Fig. 5 is executed when the start button of the vehicle equipped with the in-vehicle communication system 100 is turned on, but the present invention is not limited to this. If the configuration of the electrical devices installed in the vehicle has not been changed, the CPU 150 only needs to execute steps 300 to 308 of Fig. 5 once. Since the memory 152 stores the function and power requirements of each electrical device, the CPU 150 may read the stored data and determine the priority from the next time onwards.

[0063] (First Modification) The importance of each electrical device mounted on a vehicle changes depending on the state of the vehicle. Therefore, the in-vehicle communication system according to the first modification determines the priority depending on the state of the vehicle in which the in-vehicle communication system is mounted.

[0064] The configuration of the in-vehicle communication system according to the first modification is the same as that shown in Figures 1 to 4. The difference is the processing related to the priority determination in the control device 102. Therefore, hereinafter, the symbols shown in Figures 1 to 4 will be referred to, and the following description will mainly focus on the differences, without repeating redundant explanations.

[0065] The operation of the control device 102 according to the first modification will be described with reference to Fig. 7. The process shown in Fig. 7 is realized, similarly to Fig. 5, by the CPU 150 of the priority determination unit 110 shown in Fig. 2 reading and executing a corresponding program from the memory 152 when the start button of the vehicle equipped with the in-vehicle communication system 100 is turned on. The flowchart shown in Fig. 7 is the flowchart shown in Fig. 5 in which step 310 is replaced by step 330 and step 332 is added.

[0066] 5 , in steps 300 to 308, the CPU 150 acquires information indicating the functions and power requirements of each of the electric devices 104, 106, and 108. Then, in step 330, the CPU 150 reads the response information (i.e., the information indicating the functions and power requirements) stored in the memory 152 and determines the priority of supplying power from the control device 102 based on the functions, power requirements, and the current state of the vehicle in which the in-vehicle communication system 100 is installed. The vehicle state includes, for example, parking and normal driving. The CPU 150 can identify the vehicle state using output data from various sensors (such as a camera and an acceleration sensor) installed in the vehicle and location information from a GPS (Global Positioning System), etc.

[0067] For example, assume that the response information indicates that the electric device 104 is a front object detection camera, the electric device 106 is a rear object detection camera, and the electric device 108 is an around view monitor camera. During normal driving, the CPU 150 determines the priority so that the electric device 104 is the highest, followed by the electric devices 104, 106, and 108 in descending order. During parking, the CPU 150 determines the priority so that the electric device 108 is the highest, followed by the electric devices 108, 106, and 104 in descending order. During normal driving, the front object detection camera and the rear object detection camera are important, but the around view monitor camera is not. On the other hand, during parking, the around view monitor camera is most important, and the front object detection camera and the rear object detection camera are less important.

[0068] Thereafter, power supply is initiated in step 312 according to the priority determined in step 330. If it is determined in the following step 314 that no data has been received, CPU 150 determines in step 332 whether the vehicle state has changed. If it is determined that the vehicle state has changed, control returns to step 330, where a new priority is determined based on the current vehicle state and the returned information, as described above. Otherwise, control proceeds to step 318.

[0069] This allows the control device 102 to determine appropriate priorities depending on the vehicle state. The importance of each electrical device installed in the vehicle changes depending on the vehicle state. Therefore, it is possible to supply power preferentially to electrical devices having specific functions depending on the vehicle state.

[0070] The vehicle state also includes a state in which a function provided by an electrical device has been turned off by the user. In this case, the priority of power supply to the electrical device for which the function has been turned off may be changed so that the priority is the lowest. For example, the user can turn off an autonomous driving function (such as an automatic tracking driving function). When the function is turned off, there is no need to supply power to sensors, radar, and other devices used solely for that function.

[0071] Second Embodiment In the above, a case has been described in which one control device supplies power to a plurality of electrical devices. However, in a second embodiment, power can be supplied to some electrical devices from a plurality of control devices.

[0072] (Overall Configuration) Referring to Fig. 8, an in-vehicle communication system 200 according to the first embodiment of the present disclosure includes a first control device 102A, electric devices 106 and 108, a second control device 202, a specific electric device 204, and electric devices 206 and 208. The in-vehicle communication system 200 is mounted on a vehicle (not shown). The in-vehicle communication system 200 is configured by replacing the electric device 104 with the specific electric device 204 in the in-vehicle communication system 100 shown in Fig. 1 and adding a second control device 202 and electric devices 206 and 208. The first control device 102A is the same as the control device 102 described in the first embodiment, but different reference numerals and names are used for convenience.

[0073] The first control device 102A is, for example, a C-ECU. The specific electrical device 204 and the electrical devices 106 and 108 are targets to which power is supplied from the first control device 102A. The first control device 102A, the specific electrical device 204, and the electrical devices 106 and 108 are communicatively connected by communication lines 140, 142, and 144, respectively. The second control device 202 is, for example, a Z-ECU (Zone-Electronic Control Unit). The specific electrical device 204 and the electrical devices 206 and 208 are targets to which power is supplied from the second control device 202. The second control device 202, the specific electrical device 204, and the electrical devices 206 and 208 are communicatively connected by communication lines 240, 242, and 244, respectively. The specific electrical device 204 and each of the electrical devices 106, 108, 206, and 208 are an in-vehicle camera, a sensor, a car navigation system, or the like. Unlike the electrical devices 106, 108, 206, and 208, the specific electrical device 204 is connected to the first control device 102A and the second control device 202 and can be supplied with power from the first control device 102A and the second control device 202. The first control device 102A and the second control device 202 are connected to a bus 246. The bus 246 is, for example, a Controller Area Network (CAN).

[0074] 8, the first control device 102A and the second control device 202 are each connected to be able to supply power to three electrical devices, but this is not limited thereto. The first control device 102A and the second control device 202 may each be connected to be able to supply power to two electrical devices. Furthermore, the first control device 102A and the second control device 202 may each be connected to be able to supply power to four or more electrical devices. Furthermore, while FIG. 8 shows one specific electrical device 204 connected to the first control device 102A and the second control device 202, this is not limited thereto. Two or more electrical devices may be connected to the first control device 102A and the second control device 202.

[0075] (Configuration of Second Control Device) The second control device 202 includes a priority determination unit 210, a power supply control unit 212, a power supply unit 214, data I / O units 216, 218, and 220, and PoDL units 222, 224, and 226. Referring to FIG. 9 , the priority determination unit 210 includes a CPU 250 and a memory 252. The CPU 250 controls the memory 252. The memory 252 is, for example, a rewritable nonvolatile semiconductor memory, and stores programs executed by the CPU 250. The CPU 250 stores the results of the executed processes in the memory 252 as appropriate. The CPU 250 outputs data input from the data I / O units 216, 218, and 220 to the memory 252 for storage. Furthermore, CPU 250 reads out from memory 252 and outputs data to be output from priority determination unit 210 to power supply control unit 212 and data I / O units 216 , 218 and 220 .

[0076] Priority determination unit 210 determines the priority of supplying power from second control device 202 to specific electrical device 204 and electrical devices 206 and 208, and outputs priority information indicating the priority determined by the determination to power supply control unit 212. Power supply control unit 212 outputs output power information indicating the value of power to be output from multiple ports of power supply unit 214 to power supply unit 214 in accordance with the priority information input from priority determination unit 210. Power supply unit 214 outputs the indicated amount of power (i.e., DC power) from each output port in accordance with the output power information input from power supply control unit 212. The three output ports of power supply unit 214 are connected to PoDL units 222, 224, and 226, respectively, and the output power of power supply unit 214 is input to PoDL units 222, 224, and 226. As will be described later, when the first control device 102A is supplying power to the specific electrical device 204, the power supply unit 214 does not supply power to the PoDL unit 222 (i.e., no power is supplied from the second control device 202 to the specific electrical device 204).

[0077] Priority determination unit 210 acquires predetermined information for determining the above-described priority from electrical devices 206 and 208. To this end, priority determination unit 210 outputs a transmission request requesting the predetermined information (i.e., information indicating the functions and power requirements of the electrical devices) to data I / O units 218 and 220. Data I / O units 218 and 220 output a communication signal corresponding to the transmission request input from priority determination unit 210. Data I / O units 218 and 220 are connected to PoDL units 224 and 226, respectively, and the communication signal (i.e., the transmission request) output from data I / O units 218 and 220 is input to PoDL units 224 and 226.

[0078] Each of the PoDL units 222, 224, and 226 functions as a signal superimposing unit. That is, the PoDL unit 222 generates a superimposed signal by superimposing a communication signal input from the data I / O unit 216 on DC power input from the power supply unit 214, and outputs the superimposed signal to the communication line 240. The PoDL unit 224 superimposes a communication signal (e.g., a transmission request) input from the data I / O unit 218 on DC power input from the power supply unit 214, and outputs the superimposed signal to the communication line 242. The PoDL unit 226 superimposes a communication signal (e.g., a transmission request) input from the data I / O unit 220 on DC power input from the power supply unit 214, and outputs the superimposed signal to the communication line 244. Each of the PoDL units 222, 224, and 226 is configured to include, for example, a bias tee.

[0079] Each of the PoDL units 222, 224, and 226 also functions as a signal separator. That is, the PoDL unit 222 separates AC components from a communication signal input via the communication line 240 (i.e., a signal biased with DC power from the power supply unit 214) and outputs the separated AC components to the data I / O unit 216. The data I / O unit 216 generates digital data and outputs the digital data to the priority determination unit 210. Similarly, the PoDL unit 224 separates AC components from a communication signal input via the communication line 242 and outputs the digital data to the data I / O unit 218. The data I / O unit 218 generates digital data and outputs the digital data to the priority determination unit 210. The PoDL unit 226 separates AC components from a communication signal input via the communication line 244 and outputs the digital data to the data I / O unit 220. The data I / O unit 220 generates digital data and outputs the digital data to the priority determination unit 210.

[0080] PoDL unit 222 is connected to PoDL unit 236 of specific electrical device 204 via communication line 240, and the superimposed signal output from PoDL unit 222 is transmitted to PoDL unit 236 via communication line 240. Similarly, PoDL unit 224 is connected to the PoDL unit of electrical device 206 via communication line 242, and the superimposed signal output from PoDL unit 224 is transmitted to the PoDL unit of electrical device 206 via communication line 242. PoDL unit 226 is connected to the PoDL unit of electrical device 208 via communication line 244, and the superimposed signal output from PoDL unit 226 is transmitted to the PoDL unit of electrical device 208 via communication line 244.

[0081] (Configuration of Electrical Devices) Specific electrical device 204 includes a control unit 230, a power receiving unit 232, data I / O units 134 and 234, PoDL units 136 and 236, a functional unit 238, and a switch 239. Functional unit 238 is an element for realizing the functions of specific electrical device 204. Electrical devices 206 and 208 include the same elements as electrical device 104 shown in FIG. 1 . However, functional units that are elements for realizing the respective functions of electrical devices 206 and 208 (not shown) may be different from functional unit 138 of electrical device 104.

[0082] The data I / O unit 134 and the PoDL unit 136 function as described with respect to the electrical device 104 shown in FIG. 1 . That is, the PoDL unit 136 functions as a separator, separating an input signal into an AC component and a DC component and outputting the separated components. The separated AC component is input to the data I / O unit 134, and the separated DC component is input to the power receiving unit 232. The data I / O unit 134 receives the AC component separated by the PoDL unit 136, i.e., the communication signal, and generates digital data from the input communication signal and outputs it to the control unit 230.

[0083] The PoDL unit 236 functions as a separator, similar to the PoDL unit 136. That is, the PoDL unit 236 separates an input signal into an AC component and a DC component and outputs the separated signals. The separated AC component is input to the data I / O unit 234, and the separated DC component is input to the power receiving unit 232. The PoDL unit 236 has a configuration similar to the PoDL unit 122 (see FIG. 3). The PoDL unit 236 includes, for example, a bias tee.

[0084] The power receiving unit 232 receives the DC component separated by the PoDL unit 136, i.e., DC power, and first supplies the received power to the data I / O unit 134 and the control unit 230. This allows the control unit 230 and the data I / O unit 134 to function, and the data I / O unit 134 and the control unit 230 to receive communication signals (e.g., transmission requests) transmitted from the first control device 102A via the communication line 140. The control unit 230 and the data I / O unit 134 can also output communication signals to the communication line 140 via the PoDL unit 136. If the power supplied from the PoDL unit 136 is sufficient to perform the function of the electric device 104, the power receiving unit 232 also supplies power to the functional unit 238, which is an element for performing that function. That is, the control unit 230 controls the on / off of the switch 239 to control the power supply from the power receiving unit 232 to the functional unit 238.

[0085] For example, when the second control device 202 needs data output from the specific electrical device 204, the power receiving unit 232 also supplies power supplied from the first control device 102A to the data I / O unit 234. For example, assume that the specific electrical device 204 is a forward camera for object detection, the first control device 102A outputs image data from the specific electrical device 204 to an autonomous driving ECU, and the second control device 202 outputs the image data from the specific electrical device 204 to a recording device. In this case, the power supplied from the first control device 102A is also supplied to the data I / O unit 234. On the other hand, when the second control device 202 does not need data output from the specific electrical device 204, the power receiving unit 232 does not need to supply power to the data I / O unit 234.

[0086] 10 , control unit 230 includes a CPU 260 and a memory 262. CPU 260 controls memory 262. Memory 262 is, for example, a rewritable nonvolatile semiconductor memory, and stores programs executed by CPU 260. CPU 260 stores the results of executed processing in memory 262 as appropriate. CPU 260 outputs data input from data I / O unit 134 or 234 to memory 262 for storage. CPU 260 also reads data to be output to data I / O unit 134 or 234 from memory 262, and outputs the data to data I / O unit 134 or 234.

[0087] When power is being supplied from first control device 102A and data input from data I / O unit 134 to control unit 230 (i.e., CPU 260) is an instruction (e.g., a transmission request) to control unit 230, CPU 260 executes the instructed process and outputs the result to data I / O unit 134. For example, CPU 260 reads information (i.e., predetermined information) representing the function and power requirements of specific electrical device 204 stored in memory 262 and outputs the information to data I / O unit 134. As a result, the process result (i.e., predetermined information) is transmitted to first control device 102A via communication line 140 and received by priority determination unit 110.

[0088] When power is being supplied from the second control device 202, if data input from the data I / O unit 234 to the control unit 230 (i.e., the CPU 260) is an instruction for the control unit 230, the CPU 260 executes the instructed processing and outputs the result to the data I / O unit 234. As a result, the processing result is transmitted to the second control device 202 via the communication line 240 and received by the priority determination unit 210.

[0089] Each of the electric devices 206 and 208 operates in the same manner as the electric device 104 shown in Fig. 1. However, while the electric device 104 is connected to the control device 102, the electric devices 206 and 208 are connected to the second control device 202. Therefore, the electric devices 206 and 208 receive a transmission request from the priority determination unit 210 of the second control device 202 and transmit information indicating the functions and power requirements of the electric devices 206 and 208 to the second control device 202.

[0090] (Operation of First Control Device) The operation of the first control device 102A will be described with reference to FIG. 11 . The processing shown in FIG. 11 is realized, for example, by the CPU 150 of the priority determination unit 110 shown in FIG. 2 reading and executing a corresponding program from the memory 152. The program is read, for example, when the start button of the vehicle equipped with the in-vehicle communication system 200 is turned on. As described above, the first control device 102A is connected to the bus 246, and the CPU 150 of the priority determination unit 110 shown in FIG. 8 is connected to the bus 246 in the same manner as the CPU 250 shown in FIG. 9. The flowchart shown in FIG. 11 is the flowchart shown in FIG. 5 with the addition of steps 340, 342, and 344. Therefore, redundant description will not be repeated and the differences will be mainly described.

[0091] 5 , in steps 300 to 310, CPU 150 obtains information representing the functions and power requirements of specific electrical device 204 and electrical devices 106 and 108, and determines the priority of power supply. Subsequently, in step 340, CPU 150 determines whether to stop power supply to specific electrical device 204. If it is determined to stop power supply, control proceeds to step 342. Otherwise, control proceeds to step 312.

[0092] In step 342, the CPU 150 reads from the memory 152 information (i.e., predetermined information) indicating the function and power requirements of the specific electrical device 204 to which power supply is to be stopped, generates information indicating the stop of power supply (hereinafter referred to as stop information) including the predetermined information, and notifies the second control device 202 via the bus 246. The stop information is received by the priority determination unit 210 (specifically, the CPU 250) of the second control device 202. Stopping the power supply includes cases where the first control device 102A plans to stop the power supply and cases where power supply is not possible due to, for example, a disconnection of the communication line 140. The inability to supply power can be detected, for example, by the CPU 150 periodically communicating with the control unit 230 of the specific electrical device 204 while the first control device 102A is supplying power. If the CPU 150 cannot communicate with the control unit 230 of the specific electrical device 204, it can determine that the communication line 140 has been disconnected. If the power supply is to be stopped, the CPU 150 waits for a predetermined time, and then the control proceeds to step 344. The reason for waiting for the predetermined time is to ensure that power can be supplied uninterrupted from the second control device 202 to the specific electrical device 204, as will be described later. If power cannot be supplied, the control proceeds immediately to step 344.

[0093] In step 344, the CPU 150 changes the current priority. That is, because the power supply to the specific electrical device 204 is scheduled to be stopped or the power supply to the specific electrical device 204 has already been stopped, the CPU 150 determines a new priority excluding the specific electrical device 204. Thereafter, control proceeds to step 312, where the CPU 150 starts supplying power to the electrical devices according to the new priority. That is, the power supply from the power supply unit 114 of the first control device 102A to the specific electrical device 204 is stopped.

[0094] (Operation of Second Control Device) The operation of the second control device 202 will be described with reference to Fig. 12. The processing shown in Fig. 12 is realized, for example, by the CPU 250 of the priority determination unit 210 shown in Fig. 9 reading and executing a corresponding program from memory 252. The program is read, for example, when the start button of the vehicle equipped with the in-vehicle communication system 200 is turned on. The flowchart shown in Fig. 12 is the flowchart shown in Fig. 5 with steps 350 and 352 added. Therefore, redundant explanations will not be repeated and the differences will be mainly described.

[0095] 5 , in steps 300 to 312, CPU 250 obtains information indicating the functions and power requirements of electric devices 206 and 208, determines the priority of supplying electric power, and starts supplying electric power according to the determined priority. At this stage, as described above, electric power is supplied to specific electric device 204 from first control device 102A, and electric power is not supplied to specific electric device 204 from second control device 202. Therefore, CPU 250 does not send a transmission request to specific electric device 204 and does not receive information indicating the functions and power requirements from specific electric device 204, so specific electric device 204 is not included in the priority.

[0096] Next, if it is determined in step 314 that no data has been received, then in step 350, the CPU 250 determines whether or not a notification to stop power supply to the specific electrical device 204 has been received from the first control device 102A. Specifically, the CPU 250 determines whether or not stop information has been received from the first control device 102A. If it is determined that a stop notification has been received, control proceeds to step 352. Otherwise, control proceeds to step 318. The stop information is transmitted from the CPU 150 in step 342 shown in FIG. 11 .

[0097] In step 352, the CPU 250 changes the current priority. That is, since the CPU 250 is to start supplying power to the specific electrical device 204, it determines a new priority including the specific electrical device 204, i.e., by referring to the function and power requirements of the specific electrical device 204 included in the shutdown information. The new priority does not necessarily have to be determined so that the specific electrical device 204 has the highest priority, but is determined so that power is supplied to the specific electrical device 204. Thereafter, control proceeds to step 312, where power supply from the power supply unit 214 of the second control device 202 is started in accordance with the new priority.

[0098] As a result, when the power supply from the first control device 102A to the specific electrical device 204 is stopped, the second control device 202 can supply power to the specific electrical device 204, allowing the specific electrical device 204 to maintain its function. For example, assume that the specific electrical device 204 is a forward camera for object detection, the first control device 102A outputs image data from the specific electrical device 204 to an autonomous driving ECU, and the second control device 202 outputs image data from the specific electrical device 204 to a video recording device. During normal vehicle driving, the first control device 102A needs data from the specific electrical device 204 and therefore supplies power to the specific electrical device 204. However, during vehicle parking, the first control device 102A does not need data from the specific electrical device 204 and therefore stops the power supply to the specific electrical device 204. On the other hand, even during vehicle parking, the specific electrical device 204 needs data from the specific electrical device 204 as video recording data. Therefore, the power supply state is changed so that power is supplied from second control device 202 to specific electrical device 204. Furthermore, if communication line 140 is cut as described above, power cannot be supplied from first control device 102A to specific electrical device 204, and specific electrical device 204 will no longer function. By supplying power from second control device 202 to specific electrical device 204, the function of specific electrical device 204 continues, and output data from specific electrical device 204 is transmitted to second control device 202.

[0099] As described above, the priority determination unit 110 (specifically, CPU 150) of the first control unit 102A notifies the priority determination unit 210 (specifically, CPU 250) of the second control unit 202 of stop information via the bus 246. This allows the second control unit 202 to efficiently start supplying power to the specific electrical device 204 when the power supply from the first control unit 102A to the specific electrical device 204 is stopped.

[0100] As described above, the shutdown information notified from the first control device 102A to the second control device 202 includes information indicating the function and power requirements of the specific electrical device 204. This allows the second control device 202 to quickly change the priority so that power can be supplied to the specific electrical device 204.

[0101] The first control device 102A may notify the second control device 202 of shutdown information that does not include information indicating the function and power requirements of the specific electrical device 204. In this case, upon receiving the shutdown information from the first control device 102A, the second control device 202 transmits a transmission request from the data I / O unit 216 to the specific electrical device 204 via the PoDL unit 222 and the communication line 240. In some cases, power may not be supplied from the first control device 102A to the specific electrical device 204 due to a break in the communication line 140, for example. Therefore, the second control device 202 may supply power for communication to the specific electrical device 204 from the power supply unit 214 via the PoDL unit 222 and the communication line 240, and transmit a transmission request from the data I / O unit 216 via the communication line 240. This allows the second control device 202 to obtain information indicating the function and power requirements of the specific electrical device 204 and change the priority so that power can be supplied to the specific electrical device 204.

[0102] Furthermore, when the first control device 102A stops the power supply to the specific electrical device 204, in addition to the stop information, the first control device 102A may transmit information indicating the time (e.g., in seconds) until the power supply to the specific electrical device 204 is stopped to the second control device 202. This allows the second control device 202 to start supplying power to the specific electrical device 204 in accordance with the timing at which the power supply from the first control device 102A to the specific electrical device 204 is stopped, so that the power supply to the specific electrical device 204 is not interrupted.

[0103] In the above description, the first control device 102A is a C-ECU and the second control device 202 is a Z-ECU, but this is not limiting. The first control device 102A may be a Z-ECU separate from the second control device 202.

[0104] (Second Modification) In the above, a case has been described in which the first control device 102A notifies the second control device 202 of stoppage information before stopping the power supply from the first control device 102A to the specific electrical device 204, but this is not limiting. In the second modification, the first control device 102A notifies the specific electrical device 204 of the stoppage information, and the specific electrical device 204 requests the second control device 202 to supply power. The configuration of the in-vehicle communication system according to the second modification is the same as that shown in Fig. 8. However, because the first control device 102A does not notify the second control device 202 of the stoppage information, the bus 246 may be omitted.

[0105] (Operation of First Control Device) In the second modification, the priority determination unit 110 of the first control device 102A (specifically, the CPU 150 shown in FIG. 2) notifies the specific electrical device 204 of stop information via the communication line 140 in step 342 of FIG. 11. The stop information notified at this time does not include information indicating the function and required power.

[0106] (Operation of Electrical Device) The operation of specific electrical device 204 will be described with reference to Figure 13. The processing shown in Figure 13 is realized by CPU 260 of control unit 230 shown in Figure 10 reading and executing a corresponding program from memory 262. The program is read when power for communication is supplied from power supply unit 114 of first control device 102A to specific electrical device 204 in step 300 shown in Figure 11 and control unit 230 becomes operable.

[0107] In step 410, the CPU 260 determines whether the power supply is to be stopped. Specifically, the CPU 260 determines whether stop information has been notified from the first control device 102A. If it is determined that the power supply is to be stopped, control proceeds to step 412. If not, step 410 is repeated.

[0108] In step 412, CPU 260 notifies second control device 202 that power supply from first control device 102A will be stopped. Specifically, CPU 260 reads information indicating its own functions and power requirements (i.e., predetermined information) from memory 262, generates stop information including the predetermined information, and notifies second control device 202 of this information via communication line 240. Thereafter, this program ends.

[0109] (Operation of Second Control Device) In the second modified example, the priority determination unit 210 (specifically, the CPU 250) of the second control device 202 may execute the same program as in Fig. 12. That is, when the CPU 250 receives stop information via the communication line 240 in step 350, it determines new priorities in step 352 by referring to information indicating functions and required power included in the stop information.

[0110] As a result, when the power supply from first control device 102A to specific electrical device 204 is stopped, power can be supplied from second control device 202 to specific electrical device 204, and specific electrical device 204 can maintain its function. As described above, when specific electrical device 204 receives a notification from first control device 102A that the power supply has been stopped, it transmits stop information to second control device 202, so that second control device 202 can efficiently start supplying power to specific electrical device 204.

[0111] As described above, the stop information notified from the specific electrical device 204 to the second control device 202 includes information indicating the function and power requirements of the specific electrical device 204. This allows the second control device 202 to quickly change the priority so that power can be supplied to the specific electrical device 204.

[0112] In the above description, the case where the power supply from the first control device 102A to the specific electrical device 204 is stopped and power is supplied from the second control device 202 to the specific electrical device 204 has been described, but this is not limiting. When reducing the power supplied from the first control device 102A to the specific electrical device 204, the second control device 202 may supply the power that is insufficient in the specific electrical device 204. In this case, if the second control device 202 can receive information indicating a reduction in power, similar to the shutdown information, it can start supplying power to the specific electrical device 204 in the same manner as described above. If the second control device 202 can receive information about the power shortage in the specific electrical device 204 from the first control device 102A or the specific electrical device 204, it can supply appropriate power. Note that reducing the power supplied from the first control device 102A to the specific electrical device 204 includes setting the supplied power to zero, i.e., stopping the power supply from the first control device 102A.

[0113] Although the above description has been given of a case in which the control device has a PoDL unit corresponding to each electrical device to be supplied with power, this is not limiting. The control device may not have a PoDL unit. Alternatively, the control device may have at least one PoDL unit. Power may be supplied to some or all of the electrical devices to be supplied with power via a path separate from the communication line without going through the PoDL unit, i.e., without superimposing the power and the communication signal.

[0114] In the above description, the power supplied from the power supply unit is DC power, but this is not limiting. AC power may also be supplied from the power supply unit. If the electrical device operates on AC power, the AC power and a communication signal may be superimposed and supplied to the electrical device. The superposition and separation of the AC power and the communication signal can be performed, for example, by PLC (Power Line Communication).

[0115] Each process (each function) in the above-described embodiments may be realized by a processing circuit (circuitry) including one or more processors. The priority determination unit may be configured by an integrated circuit that combines one or more memories, various analog circuits, and various digital circuits in addition to one or more processors. The one or more memories store programs (instructions) that cause the one or more processors to execute each of the processes. The one or more processors may execute each of the processes according to the program read from the one or more memories, or according to a logic circuit designed in advance to execute each of the processes. The processor may be any of various processors suitable for computer control, such as a CPU, a GPU (Graphics Processing Unit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), and an ASIC (Application Specific Integrated Circuit). Note that the plurality of physically separated processors may cooperate with each other to execute the above processes.

[0116] Although the present disclosure has been described above by explaining the embodiments, the above-described embodiments are merely examples, and the present disclosure is not limited to only the above-described embodiments. The scope of the present disclosure is defined by the claims in the scope of the claims, taking into consideration the description of the detailed description of the invention, and includes all modifications within the meaning and scope equivalent to the wordings described therein.

[0117] 100, 200 In-vehicle communication system 102 Control device 102A First control device 104, 106, 108, 206, 208 Electrical device 110, 210 Priority determination unit 112, 212 Power supply control unit 114, 214 Power supply unit 116, 118, 120, 134, 216, 218, 220, 234 Data I / O unit 122, 124, 126, 136, 222, 224, 226, 236 PoDL unit 130, 230 Control unit 132, 232 Power receiving unit 138, 238 Functional unit 139, 239 Switch 140, 142, 144, 240, 242, 244 Communication line 150, 160, 250, 260 CPU 152, 162, 252, 262 Memory 202 Second control device 204 Specific electrical device 246 Bus 300, 302, 304, 306, 308, 310, 312, 314, 316, 318, 330, 332, 340, 342, 344, 350, 352, 400, 402, 410, 412 Step C1 Capacitor L1 Inductor T1, T2, T3 Terminal

Claims

1. An in-vehicle communication system including a first control device and a plurality of first electric devices, The first control device is A first power supply unit that outputs electric power; a plurality of first communication units corresponding to the plurality of first electric devices, a plurality of first communication paths corresponding to the plurality of first communication units, a first priority determination unit that determines a first priority for supplying power from the first power supply unit to the first electric devices, the first priority determination unit transmits a first transmission request to each of the first electric devices from the first communication units via the first communication paths; each of the plurality of first electric devices transmits information representing an importance and a required power of the first electric device to the first control device via the first communication path in response to the first transmission request; The first priority determination unit determines the first priority based on the information representing the importance and the required power received from the plurality of first electric devices.

2. 2. The in-vehicle communication system according to claim 1, wherein the first power supply unit supplies communication power required for each of the plurality of first electrical devices to communicate with the first control device via the plurality of first communication paths when the first priority determination unit transmits the first transmission request.

3. The first control device further includes at least one superimposing unit, The overlapping portion is generating a superposed signal by superposing a communication signal output from the first communication unit and the power supplied from the first power supply unit, and outputting the superposed signal to the first communication path corresponding to the first communication unit that output the communication signal; 3. The in-vehicle communication system according to claim 1, further comprising: a first communication unit that outputs the first priority determination unit a first information indicating the importance and the required power from a transmission signal transmitted from the first electric device via the first communication path; and a second communication unit that outputs the first priority determination unit a first information indicating the importance and the required power from a first electric device.

4. Each of the plurality of first electrical devices comprises: a separation unit that separates a signal including the first transmission request from the superimposed signal transmitted via the first communication path corresponding to the first electrical device; 4. The in-vehicle communication system according to claim 3, further comprising: a communication unit that transmits the information representing the importance and the required power of the first electric device to the first control device via the first communication path in response to the first transmission request separated by the separation unit.

5. The separator further separates power from the superimposed signal transmitted via the first communication path corresponding to the first electrical device; The in-vehicle communication system according to claim 4 , wherein each of the plurality of first electric devices further includes a power receiving unit that initially supplies the power separated by the separation unit to the communication unit.

6. 3. The in-vehicle communication system according to claim 1, wherein the first priority determination unit changes the first priority depending on a state of a vehicle in which the in-vehicle communication system is mounted.

7. further comprising a second control device and a plurality of second electrical devices; At least one first electric device among the plurality of first electric devices is designated as a specific electric device; The second control device is A second power supply unit that outputs electric power; a plurality of second communication units corresponding to each of the plurality of second electric devices and the specific electric device; a plurality of second communication paths corresponding to the plurality of second communication units, a second priority determination unit that determines a second priority for supplying power from the second power supply unit to the plurality of second electric devices and the specific electric device, the second priority determination unit transmits a second transmission request to each of the second electric devices from the second communication units via the second communication paths; each of the plurality of second electric devices transmits information indicating an importance and a required power of the second electric device to the second control device via the second communication path in response to the second transmission request; the second priority determination unit determines the second priority based on the information representing the importance and the required power received from the plurality of second electric devices; 3. The in-vehicle communication system according to claim 1, wherein in response to a reduction in the power supplied from the first power supply unit to the specific electrical device, the second priority determination unit changes the second priority so that power is supplied from the second power supply unit to the specific electrical device.

8. The in-vehicle communication system according to claim 7 , wherein the first priority determination unit notifies the second priority determination unit of information indicating that the power supplied from the first power supply unit to the specific electrical device will be reduced.

9. The in-vehicle communication system according to claim 7 , wherein the specific electrical device notifies the second priority determination unit of information indicating that the power supplied from the first power supply unit to the specific electrical device will be reduced.

10. The in-vehicle communication system of claim 8 , wherein the information indicative of power being reduced includes information indicative of the importance and the power requirements of the particular electrical device.

11. A control device mounted on a vehicle, A power supply unit that outputs electric power; A plurality of communication units; a priority determination unit that determines a priority for supplying power from the power supply unit to a plurality of electric devices mounted on the vehicle and corresponding to each of the plurality of communication units via a plurality of communication paths corresponding to each of the plurality of communication units, the priority determination unit transmits a transmission request to each of the plurality of electric devices from the plurality of communication units via the plurality of communication paths; receiving, from each of the plurality of electric devices, information indicative of an importance and a power requirement of the electric device in response to the transmission request, via the communication path; The priority determination unit determines the priority based on the information representing the importance and the required power received from the plurality of electric devices.

12. A control device mounted on a vehicle, A power supply unit that outputs electric power; A plurality of communication units; a priority determination unit that determines a priority for supplying power from the power supply unit to a plurality of electric devices mounted on the vehicle via a plurality of communication paths corresponding to each of the plurality of communication units, The priority determination unit determines at least one electric device among the plurality of electric devices as a specific electric device, and transmits a transmission request from the plurality of communication units via the plurality of communication paths to an electric device other than the specific electric device; receiving information indicating the importance and power requirement of an electric device other than the specific electric device via the communication path in response to the transmission request; the priority determination unit determines the priority based on the information indicating the importance and the required power received from an electric device other than the specific electric device; A control device, in response to a reduction in power supplied to the specific electrical device from an in-vehicle device other than the control device, the priority determination unit changes the priority so that power is supplied to the specific electrical device from the power supply unit.

13. An electrical device mounted on a vehicle, a separation unit that separates the communication signal from a superimposed signal on which power and a communication signal are superimposed, the superimposed signal being transmitted from a control device mounted on the vehicle via a communication path; a communication unit that transmits information representing the importance and power requirements of the electric device to the control device via the communication path in response to a transmission request included in the communication signal.

14. The separation unit further separates the power from the superimposed signal transmitted via the communication path; The electric device according to claim 13 , further comprising a power receiving unit that initially supplies the power separated by the separation unit to the communication unit.

15. The control device further includes a separation unit that receives power from an on-board device other than the control device via a path other than the communication path when the power supplied from the control device is reduced, and the separation unit is separate from the separation unit; The electric device according to claim 14 , wherein the another separator separates the electric power from a superimposed signal in which the electric power and a communication signal are superimposed and which is supplied from the in-vehicle device via the another path, and outputs the electric power to the electric power receiving unit.