In-vehicle communication systems and control devices

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

Technical Field

[0001] The present disclosure relates to an in-vehicle communication system, a control device, and an electrical device. This application claims priority based on Japanese Patent Application No. 2022-171949 filed on October 27, 2022, and incorporates all the descriptions set forth in the above Japanese application.

Background Art

[0002] In vehicles such as automobiles, various electrical devices (for example, cameras, sensors, and car navigation systems) mounted therein are supplied with electric power from an in-vehicle battery. For example, in a vehicle of a PHEV (Plug-in Hybrid Electric Vehicle) or an EV (Electric Vehicle), the output voltage of a high-voltage battery for motor drive is converted to an appropriate voltage by a power conversion device and supplied to the electrical devices inside the vehicle.

[0003] The following Patent Document 1 discloses a data communication system that determines whether power supply is possible in consideration of the supply capacity on the power supply side and the capacity on the power receiving side.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

[0005] An in-vehicle communication system according to a certain 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 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 the first priority for supplying 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 power requirements 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 power requirements received from the plurality of first electrical devices. [Brief explanation of the drawing]

[0006] [Figure 1] Figure 1 is a block diagram showing the configuration of an in-vehicle communication system according to the first embodiment of this disclosure. [Figure 2] Figure 2 is a block diagram showing the configuration of the priority determination unit shown in Figure 1. [Figure 3] Figure 3 is a block diagram showing the configuration of the PoDL (Power over Data Line) section shown in Figure 1. [Figure 4] Figure 4 is a block diagram showing the configuration of the control unit of the electrical device shown in Figure 1. [Figure 5] Figure 5 is a flowchart showing the process executed by the control device shown in Figure 1. [Figure 6] Figure 6 is a flowchart showing the process performed by the electrical device shown in Figure 1. [Figure 7] Figure 7 is a flowchart showing the process performed by the control device according to the first modified example. [Figure 8] Figure 8 is a block diagram showing the configuration of the in-vehicle communication system according to the second embodiment. [Figure 9]Figure 9 is a block diagram showing the configuration of the priority determination unit of the second control device shown in Figure 8. [Figure 10] Figure 10 is a block diagram showing the configuration of the control unit for the electrical device connected to the first control device and the second control device, as shown in Figure 8. [Figure 11] Figure 11 is a flowchart showing the process executed by the first control device shown in Figure 8. [Figure 12] Figure 12 is a flowchart showing the process performed by the second control device shown in Figure 8. [Figure 13] Figure 13 is a flowchart showing the process performed by the electrical device according to the second modified example. [Modes for carrying out the invention]

[0007] [Issues this disclosure aims to address] In vehicles, electrical devices related to basic functions such as driving, turning, and stopping are of relatively high importance and must be supplied with power preferentially over other electrical devices of relatively lower importance. However, this point is not taken into consideration in the data communication system disclosed in Patent Document 1.

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

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

[0010] [Description of Embodiments in this Disclosure] The embodiments of this disclosure are listed and described below. At least some of the embodiments described below may be combined in any way.

[0011] (1) An in-vehicle communication system relating to the first 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 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 the first priority for supplying 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, each of the plurality of first electrical devices transmits information representing the importance and power requirements 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 power requirements received from the plurality of first electrical devices.

[0012] (2) In (1) above, when the first priority determination unit transmits the first transmission request, the first power supply unit can supply the communication power necessary for each of the multiple first electrical devices to communicate with the first control device to multiple first electrical devices via multiple first communication paths. This makes it possible to suppress unnecessary power consumption.

[0013] (3) In (1) or (2) above, the first control device , smallIt may further include at least one overlapping part. The overlapping part superimposes a communication signal output from the first communication part and power supplied from the first power supply part to generate a superimposed signal, and may output the superimposed signal to a first communication path corresponding to the first communication part that output the communication signal. From a transmission signal transmitted from the first electric device via the first communication path, a signal including information representing importance and required power may be separated, and the separated information may be output to the first priority determination part via the first communication part corresponding to the first electric device that output the transmission signal. Thereby, power can be superimposed on a communication line that transmits a communication signal and supplied to an electric device. Therefore, the number of electrical wiring can be reduced.

[0014] (4) In the above (3), each of the plurality of first electric devices may include a separation part that separates a signal including a first transmission request from a superimposed signal transmitted via a first communication path corresponding to the first electric device, and as a response to the first transmission request separated by the separation part, a communication part that transmits information representing the importance and required power of the first electric device to the first control device via the first communication path. Thereby, the first control device can receive information representing the importance and required power of each of the plurality of first electric devices, and the determination of the first priority becomes possible.

[0015] (5) In the above (4), the separation part may further separate power from the superimposed signal transmitted via the first communication path corresponding to the first electric device, and each of the plurality of first electric devices may further include a power receiving part that first supplies the power separated by the separation part to the communication part. Thereby, the first electric device can transmit information representing importance and required power as a reply 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 according to the state of the vehicle equipped with the in-vehicle communication system. Thereby, an appropriate priority can be determined according to the state of the vehicle. According to the state of the vehicle, the importance of each electrical device mounted on the vehicle changes. Therefore, according to the state of the vehicle, power can be preferentially supplied to an electrical device having a specific function.

[0017] (7) In any one of (1) to (6) above, the in-vehicle communication system further includes a second control device and a plurality of second electrical devices, and at least one first electrical device among the plurality of first electrical devices is specified as a specific electrical device. The The second control device may include a second power supply unit that outputs power, a plurality of second communication units corresponding to each of the plurality of second electrical devices and the specific electrical 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 power from the second power supply unit to the plurality of second electrical devices and the specific electrical device. The second priority determination unit may transmit a second transmission request to each of the plurality of second electrical devices via the plurality of second communication paths from the plurality of second communication units. Each of the plurality of second electrical devices may transmit information representing the importance and required power of the second electrical device to the second control device via the second communication path in response to the second transmission request. The second priority determination unit may determine the second priority based on the information representing the importance and required power received from the plurality of second electrical devices. In response to receiving that the power supplied from the first power supply unit to the specific electrical device is reduced, the second priority determination unit may change the second priority so that power is supplied from the second power supply unit to the specific electrical device. Thereby, even when the power supplied from the first control Device to the specific electrical device is reduced, power supply to the specific electrical device becomes possible, and the specific electrical device can maintain its function.

[0018] (8) In (7) above, 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 is decreasing. 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 decreasing.

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

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

[0021] (11) A control device relating to the second aspect of the present disclosure is a control device mounted on a vehicle, comprising: a power supply unit that outputs power; a plurality of communication units; and a priority determination unit that determines the priority of supplying power from the power supply unit to a plurality of electrical devices mounted on the vehicle, each 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 from the plurality of communication units to each of the plurality of electrical devices via the plurality of communication paths, and receives from each of the plurality of electrical devices, via the communication paths, information representing the importance and power requirements of the electrical device in response to the transmission request, and the priority determination unit determines the priority based on the information representing the importance and power requirements received from the plurality of electrical devices. This enables the control device to supply power to a plurality of electrical devices mounted on a vehicle based on the importance of each electrical device.

[0022] (12) A control device relating to the third aspect of the present disclosure is a control device mounted on a vehicle, comprising a power supply unit that outputs power, a plurality of communication units, and a priority determination unit that determines the priority of supplying power from the power supply unit to a plurality of electrical devices mounted on the vehicle via a plurality of communication paths corresponding to each of the plurality of communication units, wherein at least one of the plurality of electrical devices is designated as a specific electrical device, the priority determination unit sends a transmission request from the plurality of communication units to electrical devices other than the specific electrical device via a plurality of communication paths, and receives from the electrical devices other than the specific electrical device information representing the importance and power requirements of the electrical device via the communication paths in response to the transmission request, and the priority determination unit determines the priority based on the information representing the importance and power requirements received from the electrical devices other than the specific electrical device, and in response to a decrease in the power supplied to the specific electrical device from an on-board device other than the control device, the priority determination unit changes the priority so that power is supplied from the power supply unit to the specific electrical device. can.

[0023] (13) An electrical device relating to the fourth aspect of the present disclosure is an electrical device mounted on a vehicle, comprising: a separation unit that separates a communication signal from a superimposed signal in which power and communication signals are superimposed, transmitted from a control device mounted on the vehicle via a communication path; and a communication unit that transmits to the control device via the communication path information representing the importance of the electrical device and the power required, in response to a transmission request included in the communication signal. This enables the control device to supply power to a plurality of electrical devices mounted on the vehicle based on the importance of each electrical device.

[0024] (14) In (13) above, the separation unit may further include a power receiving unit that separates power from the superimposed signal transmitted through the communication path and initially supplies the power separated by the separation unit to the communication unit. This enables the electrical device to transmit information representing importance and power requirements.

[0025] (15) In (14) above, the electrical device may further include a separate isolation unit, which, in response to a decrease in the power supplied from the control device, is supplied with power from an on-board device mounted on the vehicle, separate from the control device, via a path separate from the communication path, and the separate isolation unit may separate the power from the superimposed signal, which is a superimposed signal of the power supplied from the on-board device via a separate path and the communication signal, and output it to the power receiving unit. This makes it possible to supply power to the electrical device even when the power supplied from the control unit to the electrical device decreases, and the electrical device can maintain its function.

[0026] [Details of the embodiments of this disclosure] In the following embodiments, identical parts are assigned the same reference numeral. Their names and functions are also identical. Therefore, detailed descriptions of them will not be repeated.

[0027] (First Embodiment) (Overall structure) Referring to Figure 1, the in-vehicle communication system 100 according to the first embodiment of this disclosure includes a control device 102 and electrical devices 104, 106, and 108. The in-vehicle communication system 100 is mounted in a vehicle (not shown). The control device 102 is, for example, a C-ECU (Central-Electronic Control Unit). Each of the electrical devices 104, 106, and 108 is an in-vehicle camera, sensor, or car navigation system, and is powered by the control device 102. The control device 102 and the electrical devices 104, 106, and 108 are communicated via communication lines 140, 142, and 144, respectively. Each communication line constitutes a communication path for connecting the electrical device and the control unit. Although Figure 1 shows three electrical devices, it is not limited to these. The control device 102 may be connected to supply power to two electrical devices. The control device 102 may also be connected to supply power to four or more electrical devices.

[0028] (Control device configuration) The control device 102 includes a priority determination unit 110, a power control unit 112, a power supply unit 114, data I / O units 116, 118, and 120, and PoDL units 122, 124, and 126. As will be described later, each data I / O unit and its corresponding PoDL unit constitute a communication unit for the control device 102 to communicate with each electrical device. Referring to Figure 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 non-volatile semiconductor memory and stores computer programs (hereinafter simply referred to as programs) executed by the CPU 150. The CPU 150 stores the results of the executed processing in the memory 152 as appropriate. The CPU 150 outputs data input from the data I / O units 116, 118, and 120 to the memory 152 for storage. Furthermore, the CPU 150 reads data from the memory 152 for output to the power control unit 112 and the data I / O units 116, 118, and 120 from the priority determination unit 110 and outputs it.

[0029] As will be described later, the priority determination unit 110 determines the priority for supplying power from the control device 102 to the electrical devices 104, 106, and 108, and outputs information representing the priority determined by the determination (hereinafter referred to as priority information) to the power control unit 112. The power control unit 112 outputs information indicating the value of power to be output from multiple ports of the power supply unit 114 (hereinafter referred to as output power information) to the power supply unit 114 according to the priority information input from the priority determination unit 110. The power supply unit 114 outputs power of the indicated magnitude (i.e., DC power) from each output port according to the output power information input from the power 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 onboard battery (not shown) to a predetermined voltage).

[0030] The priority determination unit 110 acquires predetermined information from the electrical devices 104, 106, and 108 for determining the above-mentioned priority. To this end, the priority determination unit 110 outputs an instruction (for example, predetermined code data; hereinafter referred to as a transmission request) requesting the predetermined information via the data I / O units 116, 118, and 120. The predetermined information is information representing the function and power requirements of each electrical device. Power requirements refer to the power necessary to operate the electrical device. Power requirements are, for example, the rated power consumption of each electrical device and can be obtained from the specifications or instruction manuals of each electrical device. Power requirements may also be determined from the power consumption measured by operating each electrical device. 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 the 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] PoDL sections 122, 124 and bi1 Each of the 26 functions as a signal superposition unit. Specifically, the PoDL unit 122 generates a signal (hereinafter referred to as a superposition signal) by superimposing a communication signal (e.g., a transmission request) input from the data I / O unit 116 and DC power input from the power supply unit 114, and outputs it 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 and DC power input from the power supply unit 114, and outputs the superposition 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 and DC power input from the power supply unit 114, and outputs the superposition signal to the communication line 144.

[0032] Each of the PoDL sections 122, 124, and 126 is configured to include, for example, a bias tee. Referring to Figure 3, for example, PoDL section 122 includes a capacitor C1 placed between terminals T1 and T3, and an inductor L1 placed between terminals T2 and T3. When a communication signal (i.e., an AC signal) output from the data I / O section 116 is input to terminal T1, and DC power (i.e., a DC signal) output from the power supply section 114 is input to terminal T2, a signal in which the AC signal is superimposed on the DC component is output from terminal T3. Note that each of the PoDL sections 122, 124, and 126 is not limited to circuits using capacitors and inductors, but may also be configured as a distributed constant circuit using a stub. Communication lines 140, 142, and 144 are implemented by, for example, coaxial cables or twisted pair cables for transmitting differential signals.

[0033] Furthermore, each of the PoDL units 122, 124, and 126 also functions as a signal separation unit. Specifically, the PoDL unit 122 separates the AC component from the communication signal input via the communication line 140 (i.e., the signal biased with DC power from the power supply unit 114) and outputs it to the data I / O unit 116. Referring to Figure 3, when the communication signal input to the PoDL unit 122 via the communication line 140 is input to terminal T3, the 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 the AC component from the 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 the AC component from the communication signal input via the communication line 144 and outputs it to the data I / O unit 120. The data I / O unit 120 generates digital data and outputs it 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] PoDL unit 122 is connected to PoDL unit 136 of electrical device 104 via communication line 140, and the superimposed signal output from PoDL unit 122 is transmitted to PoDL unit 136 via communication line 140. Similarly, PoDL unit 124 is connected to PoDL unit of electrical device 106 via communication line 142, and the superimposed signal output from PoDL unit 124 is transmitted to PoDL unit of electrical device 106 via communication line 142. PoDL unit 126 is connected to PoDL unit of electrical device 108 via communication line 144, and the superimposed signal output from PoDL unit 126 is transmitted to PoDL unit of electrical device 108 via communication line 144.

[0035] (Configuration of electrical equipment) The 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. The functional unit 138 is an element for realizing the functions of the electrical device 104. Electrical devices 106 and 108 also include the same elements as the electrical device 104. However, the functional units that are elements for realizing the respective functions of electrical devices 106 and 108 may differ from the functional unit 138 of the electrical device 104.

[0036] The PoDL unit 136 functions as a separation unit, similar to the PoDL unit 122. That is, the PoDL unit 136 separates the input signal (i.e., the signal biased with DC power from the power supply unit 114) into AC and DC components and outputs them. 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 is configured similarly to the PoDL unit 122. The PoDL unit 136 includes, for example, a bias tee. When the superimposed signal input from the communication line 140 to the PoDL unit 136 is input to terminal T3 (see Figure 3), the AC component is output from terminal T1 and the 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 input DC power to the data I / O unit 134 and the control unit 130. Therefore, the control unit 130 and the data I / O unit 134 can function, and as will be described later, 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 functions of the electrical device 104, the power receiving unit 132 also supplies power to the functional unit 138, which is an element for performing the functions. As will be described later, as a result of the communication, the control unit 130 controls the on / off state of the switch 139 and controls 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 it 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] Referring to Figure 4, the control unit 130 includes a CPU 160 and a memory 162. The CPU 160 controls the memory 162. The memory 162 is, for example, a rewritable non-volatile semiconductor memory and stores the program executed by the CPU 160. The CPU 160 stores the results of the executed processing in the memory 162 as appropriate. The CPU 160 outputs data input from the data I / O unit 134 to the memory 162 for storage. The CPU 160 also reads data from the memory 162 for output to the data I / O unit 134 and outputs it to the data I / O unit 134. If the data input from the data I / O unit 134 to the CPU 160 is an instruction to the control unit 130 (for example, the transmission request described above), the CPU 160 executes the instructed processing and outputs the result to the data I / O unit 134. For example, the CPU 160 reads information (i.e., predetermined information) representing the function and power requirements of the electrical device 104 stored in the memory 162 and outputs it to the data I / O unit 134. The processing result (i.e., predetermined information) is then transmitted to the control device 102 via the communication line 140 and received by the priority determination unit 110. As will be described later, information representing the function is transmitted in order to determine importance based on the function. For example, in a vehicle, electrical devices related to the basic functions of driving, turning, and stopping are relatively important. That is, information representing the function is used as an example of information representing importance.

[0040] The function of an electrical device refers to the work it is originally intended to do. For example, an in-vehicle camera has an imaging function, a sensor has a sensing function, a car navigation system has a navigation function, and an entertainment system has an entertainment function. Therefore, information representing the function can be predetermined by classifying the electrical devices that may be installed in a vehicle according to their function. 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, depending on their purpose (i.e., subdivided function). For example, different codes can be assigned to each of the following: a forward-facing camera, a rear-facing camera, a camera for an around-view monitor, and an in-vehicle camera.

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

[0042] (Operation of the control device) The operation of the control device 102 will be explained with reference to Figure 5. The process shown in Figure 5 is realized, for example, by the CPU 150 of the priority determination unit 110 shown in Figure 2 reading the corresponding program from memory 152 and executing it. This program is read, for example, when the start button of a 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 electrical devices 104, 106, and 108, which are to be powered by the control device 102. Then, the control proceeds to step 302. Specifically, the CPU 150 instructs the power control unit 112 to supply communication power from the power supply unit 114. In response, the power control unit 112 instructs the power supply unit 114 to output communication power from the output port, and the power supply unit 114 outputs communication power from the output port in accordance with the instructions of the power control unit 112. As described above, the power output from the power supply unit 114 is output as a superimposed signal to the communication lines 140, 142, and 144 by the PoDL units 122, 124, and 126. The superimposed signal transmitted via the communication lines 140, 142, and 144 is input to the PoDL units of the electrical devices 104, 106, and 108, where the DC component is separated and input to the power receiving unit. As a result, power is first supplied from the power receiving unit to the data I / O unit and the control unit, enabling them to operate. Communication power refers to power that is less than the power required for each of the electrical devices 104, 106, and 108 to perform their functions, and is the power required to communicate with the control device 102. Communication power can be calculated from the communication functions of each electrical device installed in the vehicle. For example, the maximum value of the calculated values ​​for multiple electrical devices can be used as the communication power and stored in memory 152 beforehand.

[0044] In step 302, the CPU 150 requests information representing its own function and power requirements from each of the electrical devices 104, 106, and 108, which are to be powered by the control device 102. The control then proceeds to step 304. Specifically, as described above, the CPU 150 outputs a transmission request to the data I / O units 116, 118, and 120. As a result, as described above, the PoDL units 122, 124, and 126 output a superimposed signal, which is a superposition of the communication signal supplied from the data I / O units 116, 118, and 120 and the power supplied from the power supply unit 114, to the communication lines 140, 142, and 144. The superimposed signal transmitted via the communication lines 140, 142, and 144 is input to the PoDL units of the electrical devices 104, 106, and 108, where it is 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 operational state. The AC component is input to the data I / O unit, converted into digital data, and input to the control unit. As a result, each control unit of electrical devices 104, 106, and 108 can receive transmission requests sent from the control device 102.

[0045] In step 304, the CPU 150 determines whether it has received reply information to the transmission request sent in step 302. The reply information is information representing the function and power requirements (i.e., predetermined information). If it is determined that it has been received, control proceeds to step 306. Otherwise, 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 memory 152. After that, control proceeds to step 308.

[0047] In step 308, the CPU 150 determines whether it has received reply information from all of the electrical devices 104, 106, and 108 that are powered by the control device 102. If it determines that it has received information, control proceeds to step 310. Otherwise, control returns to step 304 and waits for reply information from the electrical devices.

[0048] In step 310, the CPU 150 reads the reply information (i.e., information representing the function and power requirements) stored in the memory 152 in step 306, and determines the priority for supplying power from the control unit 102 based on the function and power requirements. The priority includes a priority order. For example, if the reply information indicates that electrical device 104 is an object detection camera, electrical device 106 is a car navigation system, and electrical device 108 is an entertainment device, the CPU 150 can determine the priority (i.e., priority order) such that electrical device 104 has the highest priority, followed by electrical devices 104, 106, and 108 in decreasing order. For example, if the sum of the power requirements of electrical devices 104, 106, and 108 exceeds the maximum output of the power supply unit 114, power will be supplied to electrical 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, the CPU 150 starts supplying power from the power supply unit 114 to the electrical devices 104, 106, and 108 according to the priority determined in step 310. Specifically, as described above, the CPU 150 outputs priority information to the power control unit 112. The power control unit 112 then outputs output power information to the power supply unit 114 according to the priority information input from the priority determination unit 110. The power supply unit 114 outputs power (i.e., DC power) from each output port according to the output power information input from the power control unit 112. The output power of the power supply unit 114 is input to the PoDL units 122, 124, and 126 and supplied to the electrical devices 104, 106, and 108 via the communication lines 140, 142, and 144.

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

[0051] In step 316, the CPU 150 outputs the data received in step 314 to the corresponding device. The control then proceeds to step 318. For example, if the data is from an object detection camera, it is output to the 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 (such as the engine, transmission, steering, and brakes).

[0052] In step 318, the CPU 150 determines whether or not it has received a termination instruction. If it determines that it has received a termination instruction, the program terminates. Otherwise, control proceeds to step 314. The termination instruction is given, for example, by turning off the start button of a vehicle equipped with the in-vehicle communication system 100.

[0053] (Operation of electrical devices) The operation of electrical devices 104, 106, and 108 will be described below. The operation of electrical devices 104, 106, and 108 is the same. Here, the operation of electrical device 104 will be described with reference to Figure 6. The process shown in Figure 6 is realized by the CPU 160 of the control unit 130 shown in Figure 4 reading the corresponding program from memory 162 and executing it. This program is read when, in step 300 shown in Figure 5, power is supplied to the electrical device 104 from the power supply unit 114 of the control device 102 and the control unit 130 becomes operational.

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

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

[0056] After sending reply information to the control device 102, the electrical device 104 will execute its function if it receives enough power from the control device 102 to perform its function (i.e., power corresponding to the required power). Specifically, the CPU 160 of the control unit 130 turns on the switch 139, which is initially off, and power to perform the function of the electrical device 104 is supplied from the power receiving unit 132 to the function unit 138. On the other hand, if the electrical device 104 has a low priority and does not receive power from the control device 102 after sending reply information to the control device 102, the electrical device 104 cannot be started. Specifically, the switch 139 remains off.

[0057] As a result, it is possible to determine the priority of multiple electrical devices installed in a vehicle and supply power based on the determined priority. For example, by determining the priority according to the importance of each electrical device, power can be supplied preferentially to electrical devices with specific functions based on the importance of each electrical device.

[0058] As described above, the control device 102 supplies communication power to each electrical device, enabling them to communicate with the control device 102 when no power is supplied to each electrical device. This suppresses 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 onto the communication signals from the data I / O units 116, 118, and 120 to output a superimposed signal. 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 it to the electrical devices 104, 106, and 108. Therefore, the number of electrical wires can be reduced.

[0060] As described above, each electrical device includes a PoDL unit that has the function of separating communication signals from superimposed signals transmitted via a communication line, and a data I / O unit that has the communication function of transmitting information representing its importance (specifically, its function) and power requirements to the control device 102 via the communication line in response to the separated transmission request. As a result, the control device 102 can receive information representing the importance (specifically, its function) and power requirements of each of the multiple electrical devices, and can determine their priority.

[0061] As described above, the PoDL section of each electrical device separates DC power from the superimposed signal transmitted via the communication line, and each electrical device includes a power receiving section that first supplies the separated DC power to a data I / O section with communication capabilities. This enables each electrical device to transmit information representing the importance (specifically, function) and power requirements of each electrical device as a reply to a transmission request from the control device 102.

[0062] The above describes the case where the program shown in Figure 5 is executed when the start button of a vehicle equipped with the in-vehicle communication system 100 is turned on, but it is not limited to this. If the configuration of the electrical devices installed in the vehicle has not changed, the CPU 150 only needs to execute steps 300 to 308 in Figure 5 once. Since the function and power requirements of each electrical device are stored in the memory 152, the CPU 150 may read the stored data and determine the priority on subsequent occasions.

[0063] (First variation) The importance of each electrical device installed in a vehicle changes depending on the vehicle's condition. Therefore, the in-vehicle communication system according to the first modified example determines priority according to the condition of the vehicle in which the in-vehicle communication system is installed.

[0064] The configuration of the in-vehicle communication system according to the first modified example is the same as in Figures 1 to 4. The difference lies in the processing related to priority determination in the control device 102. Therefore, in the following, we will refer to the reference numerals in Figures 1 to 4 and explain mainly the differences without repeating explanations.

[0065] Referring to Figure 7, the operation of the control device 102 according to the first modified example will be explained. The process shown in Figure 7 is realized, for example, when the start button of a vehicle equipped with the in-vehicle communication system 100 is turned on, by the CPU 150 of the priority determination unit 110 shown in Figure 2 reading the corresponding program from memory 152 and executing it, similar to Figure 5. The flowchart shown in Figure 7 is the same as the flowchart shown in Figure 5, but with step 310 replaced by step 330 and step 332 added.

[0066] Similar to Figure 5, in steps 300 to 308, the CPU 150 obtains information representing the respective functions and power requirements from the electrical devices 104, 106, and 108. Then, in step 330, the CPU 150 reads the reply information (i.e., information representing functions and power requirements) stored in the memory 152 and determines the priority for power supply from the control device 102 based on the functions and power requirements and the current state of the vehicle equipped with the in-vehicle communication system 100. The state of the vehicle includes, for example, parking operations and normal driving. The CPU 150 can determine the state of the vehicle using output data from various sensors mounted on the vehicle (such as cameras and acceleration sensors) and location information from GPS (Global Positioning System).

[0067] For example, suppose the response information reveals that electrical device 104 is a front camera for object detection, electrical device 106 is a rear camera for object detection, and electrical device 108 is a camera for the surround-view monitor. Under normal driving conditions, the CPU 150 determines the priority so that electrical device 104 has the highest priority, followed by electrical devices 104, 106, and 108 in decreasing order. Under normal driving conditions, the CPU 150 determines the priority so that electrical device 108 has the highest priority, followed by electrical devices 108, 106, and 104 in decreasing order. Under normal driving conditions, the front and rear cameras for object detection are important, but the surround-view monitor camera is not. On the other hand, under normal parking conditions, the surround-view monitor camera is the most important, while the front and rear cameras for object detection are of lower importance.

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

[0069] This allows the control device 102 to determine appropriate priorities according to the vehicle's state. The importance of each onboard electrical device changes depending on the vehicle's state. Therefore, power can be preferentially supplied to electrical devices with specific functions depending on the vehicle's state.

[0070] The vehicle's state also includes a state where electrical functions have been turned off by the user. In this case, the power supply priority may be changed so that the power supply priority to the electrical device whose function has been instructed to be turned off is the lowest. For example, the user can turn off an autonomous driving function (such as an automatic tracking function). When turned off, power supply to sensors and radar used solely for that function is no longer required.

[0071] (Second Embodiment) In the above, a case was described in which one control device supplies power to multiple electrical devices, but in the second embodiment, some electrical devices can be supplied with power from multiple control devices.

[0072] (Overall structure) Refer to Figure 8, the third disclosure 2 The in-vehicle communication system 200 according to this embodiment includes a first control device 102A, electrical devices 106 and 108, a second control device 202, a specific electrical device 204, and electrical devices 206 and 208. The in-vehicle communication system 200 is mounted in a vehicle (not shown). The in-vehicle communication system 200 is the same as the in-vehicle communication system 100 shown in Figure 1, but with the electrical device 104 replaced by the specific electrical device 204, and the second control device 202 and electrical devices 206 and 208 added. 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 unit 102A is, for example, a C-ECU. Specific electrical devices 204 and electrical devices 106 and 108 are powered by the first control unit 102A. The first control unit 102A, specific electrical devices 204, and electrical devices 106 and 108 are communicated together by communication lines 140, 142, and 144, respectively. The second control unit 202 is, for example, a Z-ECU (Zone-Electronic Control Unit). Specific electrical devices 204, and electrical devices 206 and 208 are powered by the second control unit 202. The second control unit 202, specific electrical devices 204, and electrical devices 206 and 208 are communicated together by communication lines 240, 242, and 244, respectively. Specific electrical devices 204, and electrical devices 106, 108, 206, and 208 are each examples of an in-vehicle camera, sensor, or car navigation system. Unlike electrical devices 106, 108, 206, and 208, specific electrical device 204 is connected to the first control unit 102A and the second control unit 202, and can be powered by the first control unit 102A and the second control unit 202. The first control unit 102A and the second control unit 202 are connected to bus 246, which is, for example, CAN (Controller Area Network).

[0074] In Figure 8, the first control device 102A and the second control device 202 are each connected to supply power to three electrical devices, but this is not limited to them. Each of the first control device 102A and the second control device 202 may be connected to supply power to two electrical devices. Also, each of the first control device 102A and the second control device 202 may be connected to supply power to four or more electrical devices. Furthermore, in Figure 8, one specific electrical device 204 is connected to the first control device 102A and the second control device 202, but this is not limited to them. Two or more electrical devices may be connected to the first control device 102A and the second control device 202.

[0075] (Configuration of the second control unit) 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 Figure 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 non-volatile semiconductor memory and stores the program executed by the CPU 250. The CPU 250 stores the results of the executed processing 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. The CPU 250 also reads data from the memory 252 for output from the priority determination unit 210 to the power supply control unit 212 and the data I / O units 216, 218, and 220 and outputs it.

[0076] The priority determination unit 210 determines the priority for supplying power from the second control device 202 to specific electrical device 204 and electrical devices 206 and 208, and outputs priority information representing the priority determined by the determination to the power control unit 212. The power control unit 212 outputs output power information to the power supply unit 214 that indicates the value of the power to be output from multiple ports of the power supply unit 214, according to the priority information input from the priority determination unit 210. The power supply unit 214 outputs power (i.e., DC power) of the indicated magnitude from each output port according to the output power information input from the power control unit 212. The three output ports of the power supply unit 214 are connected to the PoDL units 222, 224 and 226, respectively, and the output power of the power supply unit 214 is input to the 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., the second control device 202 does not supply power to the specific electrical device 204).

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

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

[0079] Furthermore, each of the PoDL units 222, 224, and 226 also functions as a signal separation unit. Specifically, the PoDL unit 222 separates the AC component from the communication signal input via the communication line 240 (i.e., the signal biased with DC power from the power supply unit 214) and outputs it to the data I / O unit 216. The data I / O unit 216 generates digital data and outputs it to the priority determination unit 210. Similarly, the PoDL unit 224 separates the AC component from the communication signal input via the communication line 242 and outputs it to the data I / O unit 218. The data I / O unit 218 generates digital data and outputs it to the priority determination unit 210. The PoDL unit 226 separates the AC component from the communication signal input via the communication line 244 and outputs it to the data I / O unit 220. The data I / O unit 220 generates digital data and outputs it 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 PoDL unit of electrical device 206 via communication line 242, and the superimposed signal output from PoDL unit 224 is transmitted to PoDL unit of electrical device 206 via communication line 242. PoDL unit 226 is connected to PoDL unit of electrical device 208 via communication line 244, and the superimposed signal output from PoDL unit 226 is transmitted to PoDL unit of electrical device 208 via communication line 244.

[0081] (Configuration of electrical equipment) The 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. The functional unit 238 is an element for realizing the function of the specific electrical device 204. Electrical devices 206 and 208 include the same elements as the electrical device 104 shown in Figure 1. However, the functional units that are elements for realizing the respective functions of electrical devices 206 and 208, which are not shown, may differ from the 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 Figure 1. Specifically, the PoDL unit 136 functions as a separation unit, separating the input signal into AC and DC components and outputting them. 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, generates digital data from the input communication signal, and outputs it to the control unit 230.

[0083] The PoDL unit 236 functions as a separation unit, similar to the PoDL unit 136. That is, the PoDL unit 236 separates the input signal into AC and DC components and outputs them. 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 is configured similarly to the PoDL unit 122 (see Figure 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 input power to the data I / O unit 134 and the control unit 230. Therefore, the control unit 230 and the data I / O unit 134 can function, and the data I / O unit 134 and the control unit 230 can 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 functions of the electrical device 104, the power receiving unit 232 also supplies power to the functional unit 238, which is an element for performing those functions. That is, the control unit 230 controls the on / off state of the switch 239 and controls the power supply from the power receiving unit 232 to the functional unit 238.

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

[0086] Referring to Figure 10, the control unit 230 includes a CPU 260 and a memory 262. The CPU 260 controls the memory 262. The memory 262 is, for example, a rewritable non-volatile semiconductor memory and stores the program executed by the CPU 260. The CPU 260 stores the results of the executed processing in the memory 262 as appropriate. The CPU 260 outputs data input from the data I / O unit 134 or 234 to the memory 262 for storage. The CPU 260 also reads data from the memory 262 for output to the data I / O unit 134 or 234 and outputs it to the data I / O unit 134 or 234.

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

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

[0089] Each of the electrical devices 206 and 208 operates similarly to the electrical device 104 shown in Figure 1. However, while electrical device 104 is connected to control device 102, electrical devices 206 and 208 are connected to the second control device 202. Therefore, electrical devices 206 and 208 receive a transmission request from the priority determination unit 210 of the second control device 202 and transmit information representing the function and power requirements of electrical devices 206 and 208, respectively, to the second control device 202.

[0090] (Operation of the first control device) The operation of the first control device 102A will be explained with reference to Figure 11. The process shown in Figure 11 is realized, for example, by the CPU 150 of the priority determination unit 110 shown in Figure 2 reading the corresponding program from memory 152 and executing it. This program is read, for example, when the start button of a vehicle equipped with the in-vehicle communication system 200 is turned on. As mentioned above, the first control device 102A is connected to the bus 246, and the CPU 150 of the priority determination unit 110 shown in Figure 8 is connected to the bus 246 in the same way as the CPU 250 shown in Figure 9. The flowchart shown in Figure 11 is the flowchart shown in Figure 5 with steps 340, 342, and 344 added. Therefore, without repeating redundant explanations, we will mainly explain the differences.

[0091] Similar to Figure 5, in steps 300 to 310, the CPU 150 obtains information representing the function and power requirements of the specific electrical device 204 and the electrical devices 106 and 108, and determines the priority for supplying power. Subsequently, in step 340, the CPU 150 determines whether or not to stop the power supply to the specific electrical device 204. If it is determined to stop the power supply, the control proceeds to step 342. Otherwise, the control proceeds to step 312.

[0092] In step 342, the CPU 150 reads information from memory 152 representing the function and power requirements of the specific electrical device 204 whose power supply will be stopped (i.e., predetermined information), generates information indicating the suspension of power supply (hereinafter referred to as suspension information) including the predetermined information, and notifies the second control unit 202 via bus 246. The suspension information is received by the priority determination unit 210 (specifically the CPU 250) of the second control unit 202. Suspending power supply includes cases where the first control unit 102A is scheduled to stop power supply and cases where power cannot be supplied due to the disconnection of the communication line 140, etc. 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 unit 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 scheduled to be cut off, the CPU 150 waits for a predetermined time, and then the control proceeds to step 344. The reason for waiting for a predetermined time is to ensure that power can be supplied continuously 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, if it is planned to stop the power supply to the specific electrical device 204, or if 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. Then, the control moves to step 312, and 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 the second control unit) The operation of the second control device 202 will be explained with reference to Figure 12. The process shown in Figure 12 is realized, for example, by the CPU 250 of the priority determination unit 210 shown in Figure 9 reading the corresponding program from memory 252 and executing it. This program is read, for example, when the start button of a vehicle equipped with the in-vehicle communication system 200 is turned on. The flowchart shown in Figure 12 is the flowchart shown in Figure 5 with steps 350 and 352 added. Therefore, without repeating redundant explanations, we will mainly explain the differences.

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

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

[0097] In step 352, the CPU 250 changes the current priority. That is, the CPU 250 determines a new priority, including the specific electrical device 204, by referring to the function and power requirements of the specific electrical device 204 included in the shutdown information, as it will begin supplying power to the specific electrical device 204. The new priority does not need to be determined so that the specific electrical device 204 has the highest priority, but it is determined so that power is supplied to the specific electrical device 204. The control then moves to step 312, and power is supplied from the power supply unit 214 of the second control unit 202 according to 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, and the specific electrical device 204 can maintain its function. For example, suppose the specific electrical device 204 is a forward-facing camera for object detection, the first control device 102A outputs image data from the specific electrical device 204 to the automatic driving ECU, and the second control device 202 outputs image data from the specific electrical device 204 to a recording device. During normal vehicle driving, the first control device 102A needs data from the specific electrical device 204, so it supplies power to the specific electrical device 204. However, when the vehicle is parked, the first control device 102A does not need data from the specific electrical device 204, so it stops supplying power to the specific electrical device 204. On the other hand, even when the vehicle is parked, the specific electrical device 204 needs data from it as recording data. Therefore, the power supply state is changed so that power is supplied from the second control device 202 to the specific electrical device 204. Also, as described above, if the communication line 140 is disconnected, power cannot be supplied from the first control device 102A to the specific electrical device 204, and the specific electrical device 204 will cease to function. By supplying power from the second control device 202 to the specific electrical device 204, the function of the specific electrical device 204 is maintained, and the output data of the specific electrical device 204 is transmitted to the second control device 202.

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

[0100] As described above, the stop information notified from the first control device 102A to the second control device 202 includes information representing 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] Furthermore, the first control device 102A may notify the second control device 202 of stop information that does not include information representing the function and power requirements of the specified electrical device 204. In that case, upon receiving the stop information notification from the first control device 102A, the second control device 202 transmits a transmission request from the data I / O unit 216 to the specified electrical device 204 via the PoDL unit 222 and the communication line 240. In cases where power is no longer supplied from the first control device 102A to the specified electrical device 204 due to a disconnection of the communication line 140 or the like, the second control device 202 may supply communication power to the specified 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. As a result, the second control device 202 can obtain information representing the function and power requirements of the specified electrical device 204 and change the priority so that power can be supplied to the specified electrical device 204.

[0102] Furthermore, when the first control device 102A stops supplying power to the specific electrical device 204, in addition to the stop information, the first control device 102A may transmit information representing the time (for example, 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 when the power supply from the first control device 102A to the specific electrical device 204 is stopped, so as not to interrupt the power supply to the specific electrical device 204.

[0103] In the above description, the case in which the first control unit 102A is a C-ECU and the second control unit 202 is a Z-ECU was explained, but the description is not limited to this. The first control unit 102A may be a Z-ECU different from the second control unit 202.

[0104] (Second variation) The above describes a case in which the first control device 102A notifies the second control device 202 of the shutdown information before stopping the power supply from the first control device 102A to the specific electrical device 204, but the system is not limited to this. In the second modified example, the first control device 102A notifies the specific electrical device 204 of the shutdown information, and the specific electrical device 204 requests power supply from the second control device 202. The configuration of the in-vehicle communication system in the second modified example is the same as in Figure 8. However, since the first control device 102A does not notify the second control device 202 of the shutdown information, bus 246 may be omitted.

[0105] (Operation of the first control device) In the second modified example, the priority determination unit 110 of the first control device 102A (specifically, the CPU 150 shown in Figure 2) only needs to notify the specific electrical device 204 of the stop information via the communication line 140 in step 342 of Figure 11. The stop information notified at this time does not include information representing the function and power requirements.

[0106] (Operation of electrical devices) The operation of the specific electrical device 204 will be explained with reference to Figure 13. The process shown in Figure 13 is realized by the CPU 260 of the control unit 230 shown in Figure 10 reading the corresponding program from memory 262 and executing it. This program is read when, as shown in step 300 of Figure 11, the power supply unit 114 of the first control device 102A supplies power to the specific electrical device 204 and the control unit 230 becomes operational.

[0107] In step 410, the CPU 260 determines whether or not the power supply will be shut off. Specifically, the CPU 260 determines whether or not shutdown information has been notified from the first control unit 102A. If it is determined that the power supply will be shut off, the control proceeds to step 412. Otherwise, step 410 is repeated.

[0108] In step 412, the CPU 260 notifies the second control unit 202 that the power supply from the first control unit 102A will be stopped. Specifically, the CPU 260 reads information representing its own function and power requirements (i.e., predetermined information) from memory 262, generates stop information including the predetermined information, and notifies the second control unit 202 via communication line 240. After that, the program terminates.

[0109] (Operation of the second control unit) In the second modified example, the priority determination unit 210 (specifically the CPU 250) of the second control device 202 should execute the same program as in Figure 12. That is, if the CPU 250 receives stop information via the communication line 240 in step 350, in step 352 it refers to the information representing the function and power requirements included in the stop information and determines a new priority.

[0110] 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, and the specific electrical device 204 can maintain its function. As described above, when the specific electrical device 204 receives notification from the first control device 102A that the power supply will be stopped, it transmits stop information to the second control device 202, which allows the second control device 202 to efficiently start supplying power to the 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 representing the function and power requirements of the specific electrical device 204. This allows the second control device 202 to quickly change its priority so that it can supply power to the specific electrical device 204.

[0112] The above describes a case where the power supply from the first control device 102A to the specific electrical device 204 is stopped and power is supplied to the specific electrical device 204 from the second control device 202, but it is not limited to this. When the power supplied from the first control device 102A to the specific electrical device 204 is reduced, the second control device 202 may supply the power that is insufficient in the specific electrical device 204. In that case, if the second control device 202 can receive information indicating a reduction in power, similar to the stop information, it can start supplying power to the specific electrical device 204 in the same manner as described above. The second control device 202 can supply appropriate power if it 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. Note that reducing the power supplied from the first control device 102A to the specific electrical device 204 includes setting the supplied power to 0, that is, stopping the power supply from the first control device 102A.

[0113] The above describes a case where the control device has a PoDL unit corresponding to each electrical device to which power is supplied, but it is not limited to this. The control device does not have to have a PoDL unit. The control device may also have at least one PoDL unit. Power may be supplied to some or all of the multiple electrical devices to which power is supplied via a path separate from the communication line, without going through a PoDL unit, that is, without superimposing power and communication signals.

[0114] The above describes the case where the power supplied from the power supply unit is DC power, but it is not limited to this. The power supply unit may also supply AC power. If the electrical device is a device that operates on AC power, then the AC power and the communication signal can be superimposed and supplied to the electrical device. The superposition and separation of AC power and the communication signal can be done, for example, by PLC (Power Line Communication).

[0115] Each of the above embodiments (each function) may be implemented by a processing circuit (Circuitry) including one or more processors. The priority determination unit may be composed of an integrated circuit that combines one or more processors, one or more memories, various analog circuits, and various digital circuits. The one or more memories store programs (instructions) that cause the one or more processors to execute each of the above processes. The one or more processors may execute each of the above processes according to the programs read from the one or more memories, or they may execute each of the above processes according to logic circuits that have been pre-designed to execute each of the above processes. The processors may be various processors suitable for computer control, such as a CPU, GPU (Graphics Processing Unit), DSP (Digital Signal Processor), FPGA (Field Programmable Gate Array), and ASIC (Application Specific Integrated Circuit). The physically separated multiple processors may cooperate with each other to execute each of the above processes.

[0116] The present disclosure has been described above by describing embodiments, but the embodiments described above are illustrative and the present disclosure is not limited to the embodiments described above. The scope of the present disclosure is given by each claim, with reference to the description in the detailed description of the invention, and includes all modifications within the meaning and scope equivalent to the wording contained herein. [Explanation of Symbols]

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

Claims

1. An in-vehicle communication system including a first control device and a plurality of first electrical devices, The first control device is The first power supply unit that outputs 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, The system includes a first priority determination unit that determines the first priority for supplying power from the first power supply unit to the plurality of first electrical devices, 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. Each of the plurality of first electrical devices transmits to the first control device via the first communication path information representing the importance and power requirements of the first electrical device in response to the first transmission request. The in-vehicle communication system includes a first priority determination unit which determines the first priority based on the information representing the importance and required power received from the plurality of first electrical devices.

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

3. The first control device further includes at least one superimposed portion, The aforementioned superimposed portion is, A superimposed signal is generated by superimposing the communication signal output from the first communication unit and the power supplied from the first power supply unit, and the superimposed signal is output to the first communication path corresponding to the first communication unit that output the communication signal. An in-vehicle communication system according to claim 1 or 2, comprising: separating a signal containing the information representing the importance and the required power from a transmission signal transmitted from the first electrical device via the first communication path; and outputting the separated information to the first priority determination unit via the first communication unit corresponding to the first electrical device that output the transmission signal.

4. Each of the aforementioned plurality of first electrical devices is 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, The in-vehicle communication system according to claim 3, further comprising a communication unit that, in response to the first transmission request separated by the separation unit, transmits the information representing the importance and required power of the first electrical device to the first control device via a first communication path.

5. The separation unit further separates the 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 electrical devices further includes a power receiving unit that first supplies the power separated by the separation unit to the communication unit.

6. The in-vehicle communication system according to claim 1 or claim 2, wherein the first priority determination unit changes the first priority according to the state of the vehicle on which the in-vehicle communication system is installed.

7. The system further includes a second control device and a plurality of second electrical devices, At least one of the plurality of first electrical devices is designated as a specific electrical device. The second control device is The second power supply unit outputs power, A plurality of second communication units corresponding to each of the plurality of second electrical devices and the specified electrical devices, A plurality of second communication paths corresponding to each of the plurality of second communication units, The system includes a second priority determination unit that determines the second priority for supplying power from the second power supply unit to the plurality of second electrical devices and the specified electrical devices, The second priority determination unit transmits a second transmission request from the plurality of second communication units to each of the plurality of second electrical devices via the plurality of second communication paths. Each of the plurality of second electrical devices transmits information representing the importance and power requirements of the second electrical 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 required power received from the plurality of second electrical devices, In response to a decrease in the power supplied from the first power supply unit to the specified electrical device, the second priority determination unit changes the second priority so that power is supplied from the second power supply unit to the specified electrical device, according to the in-vehicle communication system according to claim 1 or 2.

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 is decreasing.

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

10. The in-vehicle communication system according to claim 8, wherein the information indicating a decrease in power includes information indicating the importance and power requirements of the specific electrical device.

11. A control device installed in a vehicle, A power supply unit that outputs power, Multiple communications units, The power supply unit includes a priority determination unit that determines the priority of supplying power from the power supply unit to a plurality of electrical devices corresponding to each of the plurality of communication units mounted on the vehicle, via a plurality of communication paths corresponding to each of the plurality of communication units, The priority determination unit sends a transmission request from the plurality of communication units to each of the plurality of electrical devices via the plurality of communication paths. From each of the aforementioned plurality of electrical devices, in response to the transmission request, information representing the importance and power requirements of the electrical device is received via the communication path. The priority determination unit is a control device that determines the priority based on the information representing the importance and required power received from the plurality of electrical devices.

12. A control device installed in a vehicle, A power supply unit that outputs power, Multiple communications units, The power supply unit includes a priority determination unit that determines the priority of supplying power from the power supply unit to a plurality of electrical devices mounted on the vehicle via a plurality of communication paths corresponding to each of the plurality of communication units, The priority determination unit designates at least one of the plurality of electrical devices as a specified electrical device and transmits a transmission request from the plurality of communication units to electrical devices other than the specified electrical device via the plurality of communication paths. From electrical devices other than the specified electrical devices, information representing the importance and power requirements of the electrical devices is received via the communication path in response to the transmission request. The priority determination unit determines the priority based on the information representing importance and required power received from electrical devices other than the specified electrical device. A control device in which, upon receiving a decrease in the power supplied to the specified 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 specified electrical device from the power supply unit.

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