In-vehicle device, program, and information processing method

Abstract

This in-vehicle device operates on an in-vehicle applied voltage, which is a voltage applied from a power supply device mounted on a vehicle, and comprises: a power reception circuit that receives an out-of-vehicle applied voltage, which is a voltage applied from the outside of the vehicle; and a control unit that controls the power reception circuit. When the out-of-vehicle applied voltage is lower than the in-vehicle applied voltage, the control unit uses a booster unit of the power reception circuit to boost the voltage value of the out-of-vehicle applied voltage to the voltage value of the in-vehicle applied voltage.

Description

Vehicle-mounted device, program, and information processing method

[0001] This technology relates to a vehicle-mounted device, a program, and an information processing method. This application claims priority based on Japanese Application No. 2024-231051 filed on December 26, 2024, and incorporates by reference all the descriptions contained in the above-mentioned Japanese application.

[0002] A vehicle is equipped with a power supply control device (see, for example, Patent Document 1) that controls power supply from a battery to a load. In the power supply control device described in Patent Document 1, a downstream semiconductor fuse is provided in the current path of the current flowing from the battery to the load, and the power supply from the battery to the load is controlled by switching the downstream semiconductor fuse on or off.

[0003] The downstream semiconductor fuse has a control terminal. For example, when the downstream semiconductor fuse is a FET (Field Effect Transistor), the control terminal is the gate. The resistance value between both ends of the downstream semiconductor fuse changes according to the voltage of the control terminal. By adjusting the voltage of the control terminal, the resistance value between both ends of the downstream semiconductor fuse is adjusted to a sufficiently small value, and the downstream semiconductor fuse is switched on. By adjusting the voltage of the control terminal, the resistance value between both ends of the downstream semiconductor fuse is adjusted to a sufficiently large value, and the downstream semiconductor fuse is switched off.

[0004] Japanese Patent Application Laid-Open No. 2013-143905

[0005] A vehicle-mounted device according to an embodiment of the present disclosure is a vehicle-mounted device that operates with an in-vehicle applied voltage, which is a voltage applied from a power supply device mounted on a vehicle, and includes a power receiving circuit that receives an out-vehicle applied voltage, which is a voltage applied from outside the vehicle, and a control unit that controls the power receiving circuit. When the out-vehicle applied voltage is lower than the in-vehicle applied voltage, the control unit performs a process of boosting the voltage value of the out-vehicle applied voltage to the voltage value of the in-vehicle applied voltage using a boosting unit of the power receiving circuit.

[0006] This is a schematic diagram illustrating the configuration of an in-vehicle system including an in-vehicle device according to Embodiment 1. This is a block diagram illustrating the internal configuration of the in-vehicle device. This is a block diagram illustrating the configuration of the power receiving circuit. This is a flowchart illustrating the processing of the control unit of the in-vehicle device. This is a block diagram illustrating the configuration of the power receiving circuit according to Embodiment 2 (bypass route). This is a flowchart illustrating the processing of the control unit of the in-vehicle device. This is a block diagram illustrating the configuration of the power receiving circuit according to Embodiment 3 (bypass route).

[0007] [Problems to be Solved by This Disclosure] The power supply control device described in Patent Document 1 does not take into consideration the need to raise the voltage value of the externally applied voltage to the voltage value of the internally applied voltage when the externally applied voltage is lower than the internally applied voltage.

[0008] This disclosure is made in view of the above circumstances and aims to provide an in-vehicle device, etc., that can perform processing to increase the voltage value of an externally applied voltage to the voltage value of an internally applied voltage.

[0009] [Effects of this disclosure] According to one aspect of this disclosure, it is possible to provide an in-vehicle device, etc., that performs processing to increase the voltage value of an externally applied voltage to the voltage value of an internally applied voltage.

[0010] [Description of Embodiments of the Disclosure] First, embodiments of the Disclosure will be listed and described. At least some of the embodiments described below may be combined in any way.

[0011] (1) An in-vehicle device according to one aspect of the present disclosure is an in-vehicle device that operates using an in-vehicle applied voltage, which is a voltage applied from a power supply device mounted on a vehicle, and comprises a power receiving circuit that receives an external applied voltage, which is a voltage applied from outside the vehicle, and a control unit that controls the power receiving circuit, wherein if the external applied voltage is lower than the in-vehicle applied voltage, the control unit uses a voltage boosting unit of the power receiving circuit to boost the voltage value of the external applied voltage to the voltage value of the in-vehicle applied voltage.

[0012] In this embodiment, an on-board device is connected to a power line extending from a power supply device such as a lead-acid battery mounted on the vehicle, and the on-board device is driven by the power supplied from the power supply device. Furthermore, on-board loads such as drive devices (actuators) for door mirrors, seat movement devices, interior lamps, etc., or various sensors are connected to the on-board device, and the on-board device may distribute power from the power supply device to these on-board loads. These on-board loads and the on-board device are connected by distribution paths that are branched and connected in parallel within the on-board device, and the on-board device may function as a power control device that controls the starting or stopping of each of these on-board loads. The on-board device is equipped with a power receiving circuit that corresponds to the in-vehicle applied voltage (supplied power) applied from the power supply device mounted on the vehicle, as well as receiving an external applied voltage applied from outside the vehicle. The external voltage applied from outside the vehicle may not only match the internal voltage applied from the power supply, but may also differ; that is, the external voltage is less than or equal to the internal voltage (external voltage ≤ internal voltage). In this regard, the control unit that controls the power receiving circuit acquires the voltage value of the external voltage applied from outside the vehicle (external voltage value) and determines whether the external voltage value is substantially the same as the internal voltage value (internal voltage value). Substantially identical includes not only cases where the external voltage value and the internal voltage value are exactly the same, but also cases where there is a difference between the external voltage value and the internal voltage value, provided that the difference is permissible in the specifications or operating characteristics of the on-board device. If the external voltage value and the internal voltage value are substantially the same, the control unit may output the external voltage to the on-board load without boosting the voltage. Furthermore, if the externally applied voltage is lower than the internally applied voltage (external applied voltage < internally applied voltage), the control unit uses the boost-up section of the power receiving circuit to boost the externally applied voltage to the same level as the internally applied voltage. Therefore, even if the externally applied voltage is lower than the internally applied voltage, the internally applied voltage, boosted to the same level as the internally applied voltage, can be applied to the on-board load connected to the on-board device. In this case, the power supply specifications are defined so that the control unit is driven by the externally applied voltage.In other words, the control unit may be equipped with a regulator or the like internally to operate at any voltage value within the range of voltage values ​​expected for the externally applied voltage. By using an on-board device equipped with such a power receiving circuit including a voltage booster, even if the State of Charge of the power supply unit mounted on the vehicle decreases, i.e., if the battery runs out and the rated voltage specified as the internally applied voltage cannot be output, the externally applied voltage applied from outside the vehicle can be boosted to the rated voltage specified as the internally applied voltage and supplied to the on-board load to start the vehicle.

[0013] (2) In an in-vehicle device according to one aspect of the present disclosure, the control unit calculates the ratio of the voltage value of the externally applied voltage to the voltage value of the internally applied voltage, derives a voltage boosting rate in the boosting unit based on the calculated ratio, and controls the boosting unit with the derived voltage boosting rate.

[0014] In this embodiment, the boost section of the power receiving circuit is configured as a boost DC / DC converter including, for example, a boost coil and a boost switch such as an FET connected in series with the boost coil. Furthermore, a gate drive circuit that outputs a gate signal such as PWM may be connected to the gate terminal of the boost switch. The control unit acquires the voltage value of the externally applied voltage (external applied voltage value) from, for example, a voltage divider circuit or a voltage sensor, and calculates the ratio (internal-external voltage ratio) between the internally applied voltage value and the internally applied voltage value predetermined as the rated voltage value output from the power supply unit by dividing the internally applied voltage value by the externally applied voltage value (internal-external voltage ratio = internally applied voltage value / externally applied voltage value). Based on the calculated internal-external voltage ratio, the control unit derives the boost rate in the boost section and controls the boost section with the derived boost rate. In this case, the control unit may calculate the duty cycle for PWM control of the boost switch based on the internal / external voltage ratio and output a control signal to the gate drive circuit to output a PWM signal corresponding to the duty cycle. For example, if the internal applied voltage is 48V and the external applied voltage is 12V, the voltage will be boosted fourfold, and the on period (Ton) of the boost switch (Q1) will be set to three times the off period (Toff) (Ton = Toff * 3). That is, the output voltage of the power receiving circuit (Vout: external applied voltage after boosting) will be the value obtained by multiplying the input voltage of the power receiving circuit (Vin: external applied voltage before boosting) by the value obtained by dividing the sum of the on period (Ton) and the off period (Toff) (Ton + Toff) by the off period (Toff), resulting in "Vout = {(Ton + Toff) / Toff} * Vin". In this way, the control unit increases the externally applied voltage according to the internal-external voltage ratio. Therefore, even if the voltage value of the externally applied voltage (external applied voltage value) is not uniformly fixed but varies, it can be increased to the same value as the internally applied voltage value which is predetermined as the rated voltage, thereby improving availability.

[0015] (3) An in-vehicle device according to one aspect of the present disclosure, wherein the power receiving circuit includes a bypass path that avoids the boost unit and a switching unit that switches between the bypass path and a boost path to which the boost unit is connected, and the control unit switches the switching unit to the bypass path when the externally applied voltage is the same voltage value as the internally applied voltage, and switches the switching unit to the boost path when the externally applied voltage is lower than the internally applied voltage.

[0016] In this embodiment, the power receiving circuit has a bypass path that avoids the boost unit and a boost path to which the boost unit is connected, arranged in parallel. A switching unit (bypass path relay, boost path relay) is provided to switch the path through which the current due to the externally applied voltage flows between the bypass path and the boost path. The switching unit may be composed of, for example, a semiconductor relay or a mechanical relay, and may include a bypass path relay located in the bypass path and a boost path relay located in the boost path. Alternatively, the switching unit may be composed of a C-contact relay provided at the branching point where the main path branches into the boost path and the bypass path. When the externally applied voltage is lower than the internally applied voltage, the control unit switches the switching unit to the boost path and boosts the externally applied voltage. When the externally applied voltage and the internally applied voltage are substantially the same voltage, the control unit switches the switching unit to the bypass path to prevent the current due to the externally applied voltage from flowing through the boost path. In a boost path, a boost coil is arranged in the boost section, and further, a reverse connection prevention circuit is arranged, for example, with the drain terminals of two FETs connected to each other. The control unit can prevent current from flowing through these boost coils and reverse connection prevention circuits by switching the switching section to a bypass path, thereby preventing current from flowing through these boost coils and reverse connection prevention circuits due to the externally applied voltage, which is a relatively high voltage value for which boosting is unnecessary. In other words, the boost coils and reverse connection prevention circuits arranged in the boost path only need to have voltage withstand characteristics against current from the externally applied voltage, which is a relatively low voltage value for which boosting is necessary. Therefore, the component costs of these boost coils and reverse connection prevention circuits can be reduced, and the increase in the product cost of the in-vehicle device can be suppressed.

[0017] (4) An in-vehicle device according to one aspect of the present disclosure includes a power receiving terminal to which a power receiving cable for applying the externally applied voltage is connected, and is electrically connected via the power receiving cable to an external power supply device that applies the externally applied voltage, and the power receiving terminal is located upstream of the voltage booster in the direction of current flow from the external power supply device.

[0018] In this embodiment, the on-board device is provided with a power receiving terminal, to which a power receiving cable for applying an externally applied voltage is connected. In this case, the externally applied voltage is a voltage output (applied) from an external power supply device such as a portable battery or a battery of another vehicle, and the on-board device and the external power supply device are connected in a way that allows power to flow through a power receiving cable such as a booster cable or battery cable. The on-board device has, for example, an outer case (enclosure), and the case is provided with a power receiving terminal to which the power receiving cable is connected. Alternatively, the power receiving terminal may be provided at the end of a cable extending from the case. Since the power receiving terminal is located upstream of the boosting unit in the direction of current flow from the external power supply device, the externally applied voltage applied via the power receiving terminal can be boosted by the boosting unit. In this way, because the on-board device is equipped with a power receiving terminal to which the power receiving cable is connected, connection to an external power supply device that applies an externally applied voltage can be made relatively easy.

[0019] (5) In one aspect of the present disclosure, an in-vehicle device is connected to an in-vehicle load downstream of the power receiving circuit in the direction of current flow from the external power supply device, and the power from the external power supply device is supplied to the in-vehicle load via the power receiving circuit.

[0020] In this embodiment, the in-vehicle device is connected to one or more in-vehicle loads such as actuators or sensors. When the power supply is operating normally, the in-vehicle device distributes and supplies power supplied from the power supply to each of these in-vehicle loads. Since these in-vehicle loads are located downstream of the power receiving circuit in the direction of current flow from the external power supply device, even if the charge level of the power supply device decreases and the power supply device does not operate normally, power from the externally applied voltage boosted by the booster section of the power receiving circuit can be distributed and supplied to each of these in-vehicle loads. Therefore, in the event of a power supply device failure, a jump start can be performed using an external power supply device that outputs an externally applied voltage lower than the internally applied voltage to the in-vehicle device and the in-vehicle loads connected to the in-vehicle device, which use the internally applied voltage as its input voltage. By driving these in-vehicle devices and loads, the vehicle can be started.

[0021] (6) In one aspect of the present disclosure, the in-vehicle device has an in-vehicle applied voltage of 48V and an out-of-vehicle applied voltage of 12V.

[0022] In this embodiment, the voltage value of the voltage applied inside the vehicle is 48V, meaning that the vehicle on which the on-board device is installed conforms to the LV148 on-board power supply standard, for example. In contrast, the voltage value of the voltage applied outside the vehicle is 12V, which is the driving voltage commonly used in passenger cars, and corresponds to the output voltage when performing a jump start using a vehicle with a 12V power supply specification, for example. Even in such a case, the on-board device boosts the 12V voltage input as the externally applied voltage to 48V, which is required for a vehicle conforming to the LV148 on-board power supply standard, so that a jump start can be performed on a vehicle conforming to the LV148 on-board power supply standard using a vehicle with a 12V driving voltage.

[0023] (7) An information processing method according to one aspect of the present disclosure involves a computer that controls a power receiving circuit mounted on an in-vehicle device that takes an in-vehicle applied voltage, which is a voltage applied from a power supply device mounted on the vehicle, as the input voltage, and which receives an external applied voltage, which is a voltage applied from outside the vehicle, and when the external applied voltage is lower than the in-vehicle applied voltage, the computer causes the computer to perform a process using the voltage boosting unit of the power receiving circuit to boost the voltage value of the external applied voltage to the voltage value of the in-vehicle applied voltage.

[0024] In this embodiment, an information processing method is provided that causes a computer to function as an in-vehicle device that performs processing to increase the voltage value of the externally applied voltage to the voltage value of the internally applied voltage.

[0025] (8) A program according to one aspect of the present disclosure is installed in an in-vehicle device that takes an in-vehicle applied voltage, which is a voltage applied from a power supply device installed in the vehicle, as its input voltage, and causes a computer that controls a power receiving circuit that receives an external applied voltage, which is a voltage applied from outside the vehicle, to execute a process using the voltage boosting unit of the power receiving circuit to boost the voltage value of the external applied voltage to the voltage value of the in-vehicle applied voltage when the external applied voltage is lower than the in-vehicle applied voltage.

[0026] In this embodiment, a program can be provided that causes the computer to function as an in-vehicle device that performs processing to increase the voltage value of the externally applied voltage to the voltage value of the internally applied voltage.

[0027] [Details of Embodiments of the Disclosure] The Disclosure will be described in detail based on the drawings illustrating its embodiments. An in-vehicle device 1 according to an embodiment of the Disclosure will be described below with reference to the drawings. However, the Disclosure is not limited to these examples and is intended to include all modifications within the meaning and scope of the claims, as indicated by the claims.

[0028] (Embodiment 1) Hereinafter, embodiments will be described based on the drawings. Figure 1 is a schematic diagram illustrating the configuration of an in-vehicle system S including an in-vehicle device 1 according to Embodiment 1. Figure 2 is a block diagram illustrating the internal configuration of the in-vehicle device 1. The in-vehicle system S consists of an in-vehicle device 1 mounted on a vehicle C and a power supply device 3 that supplies power to the in-vehicle device 1. In the in-vehicle system S, when the power supply device 3 fails to function due to a decrease in charge level, an external power supply device 5 is connected to the in-vehicle device 1 via a power receiving cable 51 such as a booster cable or battery cable, enabling power to be supplied.

[0029] The in-vehicle device 1 and the power supply unit 3 are connected via power lines 31, and each of the multiple branched power lines 31 (distribution paths) in the in-vehicle device 1 is connected to each of the multiple in-vehicle loads 4. In this way, the in-vehicle device 1 may function as a power control device that distributes power from the power supply unit 3 to each of these in-vehicle loads 4 and controls the starting or stopping of each of these in-vehicle loads 4. Furthermore, the in-vehicle device 1 may be connected to multiple in-vehicle ECUs via an in-vehicle network that communicates according to the CAN (Controller Area Network), CAN-FD, or Ethernet (registered trademark) communication protocol. In this case, the in-vehicle device 1 may function as a relay device such as a CAN gateway or Ethernet switch that relays communication data to these multiple in-vehicle ECUs.

[0030] Vehicle C is equipped with a power supply unit 3 consisting of a lead-acid battery, an alternator, or a secondary battery. In this case, for example, the power supply unit 3 using a lead-acid battery and the power supply unit 3 using an alternator or secondary battery may be configured as separate power supply units 3. The power supply unit 3 using an alternator or secondary battery may include, for example, a DC-DC converter or a regulator. The power supply unit 3 and the on-board device 1 are connected by a power line 31. The power supply unit 3 and the on-board device 1 are not limited to being directly connected by the power line 31, but may also be indirectly connected with an electrical box (junction box) such as a relay box or fuse box, or a DC-DC converter, etc., interposed between the power supply unit 3 and the on-board device 1.

[0031] The in-vehicle device 1 includes a power receiving circuit 2 and a control unit 11 composed of a microcontroller or the like. A power line 31 extending from the power supply device 3 is connected to the output side of the power receiving circuit 2 provided in the in-vehicle device 1. A power receiving terminal 27 is connected to the input side of the power receiving circuit 2. The output side of the power receiving circuit 2 is connected upstream of the branching point of the power line 31 (distribution path), which is branched into multiple paths corresponding to each of the in-vehicle loads 4, in the direction of current flow from the power supply device 3. In this way, the power line 31 and the power receiving circuit 2 are connected in parallel in the in-vehicle device 1. In this embodiment, the power receiving circuit 2 is connected in parallel to the power line 31 from the power supply device 3, but it is not limited to this configuration, and the power receiving circuit 2 may be arranged in series with respect to the power line 31.

[0032] A relay may be placed in each of the multiple power lines 31 (distribution paths) that are branched to correspond to each of the vehicle loads 4. The relays are, for example, semiconductor relays, mechanical relays, or on / off switches. Therefore, a parallel circuit consisting of multiple relays is formed by the relays placed in each of the multiple branched power lines 31 (distribution paths), that is, these multiple relays are connected in parallel. In each of the multiple branched power lines 31 (distribution paths), the vehicle loads 4 are connected downstream of the relay in the direction of current flow from the power supply unit 3.

[0033] The vehicle loads 4 are, for example, car air conditioners, lamps, or actuators such as drive motors. These vehicle loads 4 are started or stopped by the opening and closing control (on / off control) of relays located in each of the multiple branched power lines 31 (distribution paths). The vehicle device 1 functions as a power control device that controls the starting or stopping of the vehicle loads 4 by performing the opening and closing control (on / off control) of these relays.

[0034] Multiple branched power lines 31 (distribution paths) may be connected to an in-vehicle ECU. The in-vehicle ECU includes a microcontroller with communication functions and performs predetermined calculation processing based on values ​​detected from sensors or output values ​​from various switches.

[0035] The on-board device 1 may function as a power control device that controls the starting or stopping of on-board loads 4, etc., and may also be a device that has a relay function such as a CAN gateway. Alternatively, the on-board device 1 may be an integrated ECU (vehicle computer) that comprehensively controls the entire vehicle C and has a relay function. Alternatively, the on-board device 1 may be individual ECUs connected under the integrated ECU and located in each area of ​​the vehicle C. Alternatively, the on-board device 1 may be configured as a body ECU, etc., to which various switches, sensors, or actuators, on-board loads 4 are connected, and which controls the body system actuators of the vehicle C. Alternatively, the on-board device 1 may be a PLB (Power LAN Box) that, in addition to relaying communications, also functions as a power distribution device that distributes and relays power output from a power supply device 3 such as a secondary battery and supplies power to on-board loads 4 such as actuators.

[0036] The external power supply device 5 is, for example, the battery of another vehicle C or a portable battery, and outputs a predetermined voltage. The external power supply device 5 and vehicle C are connected in a way that allows power to pass through the power receiving cable 51, so that a jump start can be performed using the external power supply device 5, and vehicle C can be started even if the power supply device 3 of vehicle C fails to function due to insufficient charge. At this time, the power receiving cable 51 is connected to the power receiving terminal 27 of the on-board device 1, and power from the external power supply device 5 is supplied to the on-board device 1 via the power receiving cable 51 and the power receiving terminal 27. If the voltage applied from the external power supply device 5 (external applied voltage) is lower than the in-vehicle applied voltage value which is predetermined as the rated voltage value output from the power supply device 3, the on-board device 1 boosts the external applied voltage applied from the external power supply device 5 to the same value as the in-vehicle applied voltage value.

[0037] The in-vehicle device 1 includes a control unit 11, a storage unit 12, a communication unit 13, and an input / output interface 14. The control unit 11 and other components may be configured as a microcomputer (MPC). Furthermore, the in-vehicle device 1 includes a power receiving circuit 2 that performs input / output processing of sensor values ​​and control signals with the control unit 11, which is configured as a microcomputer or the like. The control unit 11 is configured as a CPU (Central Processing Unit) or an MPU (Micro Processing Unit), and performs various control processing and calculation processing by reading and executing a control program P (program product) and data pre-stored in the storage unit 12.

[0038] The storage unit 12 is composed of volatile memory elements such as RAM (Random Access Memory), non-volatile memory elements such as ROM (Read Only Memory), EEPROM (Electrically Erasable Programmable ROM), or flash memory, or a combination of these storage devices, and stores in advance the control program P (program product) and data referenced during processing. The control program P (program product) stored in the storage unit 12 may be a control program P (program product) read from a recording medium M that the in-vehicle device 1 can read. Alternatively, the control program P (program product) may be downloaded from an external computer (not shown) connected to a communication network (not shown) and stored in the storage unit 12.

[0039] The communication unit 13 is an input / output interface using a communication protocol such as CAN, CAN-FD, or Ethernet (Ethernet / registered trademark), and the control unit 11 communicates with the in-vehicle ECU connected to the in-vehicle network via the communication unit 13. In the in-vehicle device 1, there may be multiple communication units 13.

[0040] The input / output interface 14 is, for example, a communication interface for serial communication. The input / output interface 14 includes a plurality of terminals (output terminals), and each terminal may be connected to a signal line 140 that extends to the voltage detection unit 25, the boost gate drive circuit 213 of the boost unit 21, and the gate drive circuit 221 of the reverse connection prevention circuit 22. Furthermore, the terminals of the input / output interface 14 may also be connected to a signal line 140 that extends to a relay that supplies and stops power to the on-board load 4. The signal line 140 is composed of, for example, a serial cable, a wire harness, or a conductive cable (direct wire) that transmits only one signal.

[0041] Figure 3 is a block diagram illustrating the configuration of the power receiving circuit 2. The power receiving circuit 2 includes a voltage detection unit 25, a reverse connection prevention circuit 22, a boost unit 21, and a boost path 23 to which these parts are connected. In the direction of current flow from the external power supply device 5, the power receiving terminal 27 is connected to the upstream side of the power receiving circuit 2, and the on-board load 4 is connected to the downstream side of the power receiving circuit 2. That is, in the boost path 23 of the power receiving circuit 2, the power receiving terminal 27 is located on the upstream side, and the on-board load 4 is located on the downstream side.

[0042] The reverse connection prevention circuit 22 is configured, for example, by connecting the drain terminals of two FETs in series. A branch line connected to the voltage detection unit 25 branches off from the boost path 23 between the power receiving terminal 27 and the reverse connection prevention circuit 22. Branch lines further branch off from this branch line are connected to a gate drive circuit 221 that applies a gate voltage to the gate terminals of the two FETs constituting the reverse connection prevention circuit 22. The gate drive circuit 221 is connected to a control unit 11, which is configured as a microcontroller or the like, in a signal-to-signal communication manner.

[0043] The voltage detection unit 25 is configured, for example, as a voltage divider circuit or a voltage sensor, and detects the voltage value of the external applied voltage applied from the external power supply device 5 connected via the power receiving terminal 27 and the power receiving cable 51, and outputs it to the control unit 11. As a result, the control unit 11 can obtain the voltage value of the external applied voltage output from the external power supply device 5. If the voltage detection unit 25 is configured as a voltage divider circuit, the control unit 11 may be driven using the voltage divided by the voltage detection unit 25. In other words, the power supply specifications of the control unit 11 may be defined so that it is driven by the external applied voltage.

[0044] In the flowing direction of the current flowing from the off-vehicle power supply device 5, a boosting unit 21 is provided on the downstream side of the reverse connection prevention circuit 22 in the boosting path 23. The boosting unit 21 may be constituted by a boost type DC / DC converter including a boost coil 211, a boost switch 212, and a gate drive circuit 213 for boosting. The boost coil 211 is arranged in the boosting path 23 and is connected in series with the reverse connection prevention circuit 22. The boost switch 212 is constituted by, for example, a FET or the like, a drain terminal is installed in the boosting path 23, and a source terminal is grounded to the ground. A gate drive circuit 213 for boosting is connected to the gate terminal of the boost switch 212, and the gate drive circuit 213 for boosting is communicably connected to a control unit 11 constituted by a microcomputer or the like via a signal line.

[0045] In the boosting path 23, a diode may be connected in the forward direction on the downstream side of the boosting unit 21. A branch line branched from the power supply line 31 on the upstream side of the diode is connected to the microcomputer constituting the control unit 11, and the control unit 11 (microcomputer) may be driven by the power supplied via the branch line. Further, the control unit 11 (microcomputer) may function as a battery voltage monitoring unit that monitors the voltage (battery voltage) output from the power supply device 3.

[0046] The voltage (Vin) input to the power receiving circuit 2 is boosted by the boosting unit 21 according to the ratio between the in-vehicle applied voltage value and the off-vehicle applied voltage value, and becomes the voltage (Vout) output from the power receiving circuit 2. That is, the input voltage (Vin) of the power receiving circuit 2 corresponds to the off-vehicle applied voltage applied from the off-vehicle power supply device 5, and the output voltage (Vout) of the power receiving circuit 2 corresponds to the off-vehicle applied voltage boosted to the same voltage value as the in-vehicle applied voltage.

[0047] For example, when the voltage value of the in-vehicle applied voltage (in-vehicle applied voltage value) is 48 V and the voltage value of the out-of-vehicle applied voltage (out-of-vehicle applied voltage value) is 12 V, the boost ratio is 4 times. At this time, the control unit 11 (microcomputer) outputs a control signal to the boost gate drive circuit 213 so as to perform PWM control in which the on period (Ton) of the boost switch 212 is 3 times the off period (Toff) "3 = (48 - 12) / 12". That is, the control unit 11 (microcomputer) controls the boost gate drive circuit 213 so that the input voltage (Vin) and the output voltage (Vout) of the power receiving circuit 2 are a value obtained by multiplying the value obtained by dividing the sum of the on period (Ton) and the off period (Toff) by the off period (Toff) "Vout = { (Ton + Toff) / Toff} * Vin". When the ratio between the in-vehicle applied voltage value and the out-of-vehicle applied voltage value is 1, that is, when the in-vehicle applied voltage value and the out-of-vehicle applied voltage value are both the same voltage value, such as 48 V, the control unit 11 (microcomputer) sets the on period (Ton) to 0, that is, turns off the boost switch 212.

[0048] Figure 4 is a flowchart illustrating the processing of the control unit 11 of the in-vehicle device 1. When the out-of-vehicle power supply device 5 is connected to the vehicle C, the control unit 11 of the in-vehicle device 1 performs the following processing.

[0049] The control unit 11 of the in-vehicle device 1 acquires the voltage value of the out-of-vehicle applied voltage, which is the voltage applied from the out-of-vehicle power supply device 5 (S101). The control unit 11 of the in-vehicle device 1 acquires the voltage value (out-of-vehicle applied voltage value) of the out-of-vehicle applied voltage applied from the out-of-vehicle power supply device 5 from, for example, a voltage detection unit 25 configured by a voltage dividing circuit or a voltage sensor. The control unit 11 of the in-vehicle device 1 may store the acquired out-of-vehicle applied voltage value in the storage unit 12 in association with the acquisition time point.

[0050] The control unit 11 of the in-vehicle device 1 calculates the ratio between the acquired voltage value of the out-of-vehicle applied voltage and the voltage value of the in-vehicle applied voltage, which is the voltage applied from the power supply device 3 (S102). The control unit 11 of the in-vehicle device 1 acquires the voltage value (in-vehicle applied voltage value) of the in-vehicle applied voltage previously stored in the storage unit 12 by referring to the storage unit 12.

[0051] The control unit 11 of the in-vehicle device 1 outputs a control signal generated according to the calculated ratio to the boost unit 21 (S103). The control unit 11 of the in-vehicle device 1 calculates the ratio of the in-vehicle applied voltage to the external applied voltage (in-vehicle-external voltage ratio) by, for example, dividing the in-vehicle applied voltage by the external applied voltage. The control unit 11 of the in-vehicle device 1 calculates the on period (Ton) and off period (Toff) of the boost switch 212 so that the in-vehicle-external voltage ratio is as calculated. The control unit 11 of the in-vehicle device 1 may also calculate the on period (Ton) and off period (Toff) so that the in-vehicle-external voltage ratio (Vout / Vin) is the value obtained by adding the on period (Ton) and off period (Toff) and dividing by the off period (Toff), "Vout / Vin = (Ton + Toff) / Toff".

[0052] If the in-vehicle applied voltage is, for example, 48V in accordance with the LV148 in-vehicle power supply standard, and the external power supply device 5, which is composed of the battery of another vehicle C or a portable battery, is 12V, then the on period (Ton) will be three times the off period (Toff), and the PWM duty cycle will be 75%. However, if both the in-vehicle applied voltage and the external applied voltage are 48V, then the on period (Ton) will be 0, and the boost switch 212 will be open (off).

[0053] The control unit 11 of the in-vehicle device 1 outputs a control signal corresponding to the internal / external voltage ratio to the boost gate drive circuit 213. The boost gate drive circuit 213 then outputs a PWM signal with a duty cycle corresponding to the control signal to the gate terminal of the boost switch 212. As a result, the boost switch 212 is controlled to open and close based on the PWM signal, and the energy stored in the boost coil 211 during the ON period (Ton) of the boost switch 212 is output from the power receiving circuit 2 during the OFF period (Toff). This allows the power receiving circuit 2 to output an externally applied voltage that has been boosted to the same voltage value as the internally applied voltage.

[0054] (Embodiment 2) Figure 5 is a block diagram illustrating the configuration of the power receiving circuit 2 according to Embodiment 2 (bypass path 24). The power receiving circuit 2 in this embodiment is connected to the power receiving terminal 27, similar to Embodiment 1, and includes a voltage detection unit 25, a reverse connection prevention circuit 22, a boost unit 21, and a boost path 23 to which these parts are connected. Furthermore, the power receiving circuit 2 in this embodiment includes a bypass path 24 that branches off from between the power receiving terminal 27 and the reverse connection prevention circuit 22 in the boost path 23.

[0055] The bypass path 24 has its downstream and upstream ends connected to a branching point in the boost path 23 between the power receiving terminal 27 and the reverse connection prevention circuit 22, and to a branching point between the diode and the vehicle load 4. Between these branching points, the boost path 23 and the bypass path 24 form a parallel circuit. The bypass path 24 is provided with a bypass path relay 261, which is, for example, a semiconductor relay or a mechanical relay.

[0056] In the boost path 23, the reverse connection prevention circuit 22 functions as a relay for the boost path that controls the opening and closing of the boost path 23. The reverse connection prevention circuit 22 is configured, for example, by connecting two FETs, including parasitic diodes, in series, with the anodes of the parasitic diodes connected to each other, or the cathodes connected to each other. In the reverse connection prevention circuit 22 configured in this reverse series connection of two FETs, the start and stop of power supply in the boost path 23 can be controlled by controlling the opening and closing (on / off) of the two FETs. Alternatively, the start and stop of power supply in the boost path 23 may be controlled by controlling the opening and closing (on / off) of an FET connected so that the parasitic diode is in the forward direction in the current flow direction of the boost path 23 (anode connected to the upstream side) while the FET connected so that the parasitic diode is in the reverse direction (cathode connected to the upstream side) is closed (on).

[0057] These bypass relays 261 and reverse connection prevention circuits 22 (two FETs connected in reverse series) that function as relays for the boost circuit are connected via signal lines to a control unit 11, which is composed of a microcontroller or the like, as in Embodiment 1. The bypass relays 261 and reverse connection prevention circuits 22 constitute a switching unit 26, and the switching unit 26 controls the opening and closing (on / off control) of the bypass relays 261 and reverse connection prevention circuits 22 based on a switching signal from the control unit 11 (microcontroller), switching the current flowing from the external power supply device 5 to either the bypass circuit 24 or the boost circuit 23.

[0058] The control unit 11 (microcontroller) can switch to the bypass path 24 by closing (turning on) the bypass path relay 261 and opening (turning off) the reverse connection prevention circuit 22 when the external applied voltage is the same voltage value as the internal applied voltage (48V), i.e., when the external applied voltage is 48V, thereby allowing the current flowing from the external power supply device 5 to flow through the bypass path 24. The control unit 11 (microcontroller) can switch to the boost path 23 by opening (turning off) the bypass path relay 261 and closing (turning on) the reverse connection prevention circuit 22 when the external applied voltage is lower than the internal applied voltage (48V), i.e., when the external applied voltage is 12V, thereby allowing the current flowing from the external power supply device 5 to flow through the boost path 23.

[0059] Figure 6 is a flowchart illustrating the processing of the control unit 11 of the in-vehicle device 1. When the external power supply device 5 is connected to the vehicle C, the control unit 11 of the in-vehicle device 1 performs the following processing.

[0060] The control unit 11 of the in-vehicle device 1 acquires the voltage value of the externally applied voltage, which is the voltage applied from the external power supply device 5 (S201). The control unit 11 of the in-vehicle device 1 executes the process of S201 in the same manner as S101 in Embodiment 1.

[0061] The control unit 11 of the in-vehicle device 1 determines whether the externally applied voltage is the same as the internally applied voltage (S202). The control unit 11 of the in-vehicle device 1 determines whether the externally applied voltage and the internally applied voltage are the same voltage, for example, both being 48V.

[0062] If they are the same (S202: YES), the control unit 11 of the in-vehicle device 1 switches the switching unit 26 to the bypass path 24 (S2021). If the externally applied voltage and the internally applied voltage are both 48V and have the same voltage value, that is, if the voltage output from the external power supply device 5 is the same voltage value (for example, 48V) as the voltage output from the power supply device 3, the control unit 11 of the in-vehicle device 1 switches the switching unit 26 to the bypass path 24.

[0063] When the control unit 11 of the in-vehicle device 1 switches the switching unit 26 to the bypass path 24, it closes (turns on) the bypass path relay 261 and opens (turns off) the reverse connection prevention circuit 22 (relay for the boost path). By switching the switching unit 26 to the bypass path 24, the current from the external power supply device 5 flows through the bypass path 24 without flowing through the boost path 23 where the reverse connection prevention circuit 22 and the boost coil 211 are located.

[0064] If they are not the same (S202: NO), the control unit 11 of the in-vehicle device 1 switches the switching unit 26 to the boost path 23 (S203). If the externally applied voltage and the internally applied voltage are not both the same voltage value of 48V, for example, if the voltage output from the external power supply device 5 is a lower voltage value (for example, 12V) than the voltage output from the power supply device 3 (for example, 48V), the control unit 11 of the in-vehicle device 1 switches the switching unit 26 to the boost path 23.

[0065] When the control unit 11 of the in-vehicle device 1 switches the switching unit 26 to the boost path 23, it opens (turns off) the bypass path relay 261 and closes (turns on) the reverse connection prevention circuit 22 (relay for the boost path). By switching the switching unit 26 to the boost path 23, the current from the external power supply device 5 flows through the boost path 23, where the reverse connection prevention circuit 22 and the boost coil 211 are located, without flowing through the bypass path 24.

[0066] The control unit 11 of the in-vehicle device 1 calculates the ratio between the acquired external applied voltage value and the in-vehicle applied voltage value, which is the voltage applied from the power supply unit 3 (S204). The control unit 11 of the in-vehicle device 1 outputs a control signal generated according to the calculated ratio to the boost unit 21 (S205). The control unit 11 of the in-vehicle device 1 executes the processes from S204 to S205 in the same manner as S102 to S103 in Embodiment 1.

[0067] (Embodiment 3) Figure 7 is a block diagram illustrating the configuration of a power receiving circuit according to Embodiment 3 (bypass route). The power receiving circuit 2 in this embodiment is connected to the power receiving terminal 27, similar to Embodiment 1, and includes a voltage detection unit 25, a reverse connection prevention circuit 22, a boost unit 21, and a boost route 23 to which these parts are connected, and also includes a bypass route 24, a switching unit 26, and a bypass route relay 261, similar to Embodiment 2.

[0068] The switching unit 26 is composed of a bypass relay 261 and a boost relay 262. In this case, the boost relay 262 may be the downstream FET of the two FETs that constitute the reverse connection prevention circuit 22. That is, in the two FETs that constitute the reverse connection prevention circuit 22, the FET located on the upstream side in the direction of current flow is connected in the forward direction with its anode facing upstream, and the FET located on the downstream side in the direction of current flow is connected in the reverse direction with its anode facing downstream, and the downstream FET may function as the boost relay 262.

[0069] In the boost path 23, the branching point where the bypass path 24 branches off, i.e., the upstream end of the bypass path 24, is positioned between the upstream FET constituting the reverse connection prevention circuit 22 and the downstream FET functioning as the boost path relay 262. The downstream FET functioning as the boost path relay 262 is also controlled to open and close by the control unit 11, similar to Embodiment 2.

[0070] In this case, the upstream FET constituting the reverse connection prevention circuit 22 may be kept normally closed (on). Then, similar to Embodiment 2, the start and stop of power supply in the boost path 23 can be controlled by controlling the opening and closing of the downstream FET which functions as a boost path relay 262.

[0071] The control unit 11 (microcontroller) can switch to the bypass path 24 by closing (turning on) the bypass path relay 261 and opening (turning off) the downstream FET, which functions as a boost path relay 262, when the external applied voltage is the same voltage value as the internal applied voltage (48V), i.e., when the external applied voltage is 48V, thereby allowing the current flowing from the external power supply device 5 to flow through the bypass path 24. The control unit 11 (microcontroller) can switch to the boost path 23 by opening (turning off) the bypass path relay 261 and closing (turning on) the downstream FET, which functions as a boost path relay 262, when the external applied voltage is lower than the internal applied voltage (48V), i.e., when the external applied voltage is 12V, thereby allowing the current flowing from the external power supply device 5 to flow through the boost path 23. In either case, the control unit 11 (microcontroller) keeps the upstream FET constituting the reverse connection prevention circuit 22 permanently closed (on).

[0072] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the invention is indicated by the claims and not in the sense described above, and all modifications within the sense and scope equivalent to the claims are intended to be included.

[0073] With respect to the multiple claims described in the claims, they may be combined with each other regardless of the form of reference. Multiple dependent claims that depend on multiple claims may be described in the claims. Multiple dependent claims that depend on multiple dependent claims may be described. Even if multiple dependent claims that depend on multiple dependent claims are not described, this does not limit the description of multiple dependent claims that depend on multiple dependent claims.

[0074] C Vehicle S In-vehicle system 1 In-vehicle device 11 Control unit 12 Memory unit M Recording medium P Control program (program product) 13 Communication unit 14 Input / output I / F 2 Power receiving circuit 21 Boost unit 211 Boost coil 212 Boost switch 213 Boost gate drive circuit 22 Reverse connection prevention circuit (relay for boost path) 221 Gate drive circuit 23 Boost path 24 Bypass path 25 Voltage detection unit 26 Switching unit 261 Bypass path relay 262 Boost path relay 27 Power receiving terminal 3 Power supply unit 31 Power line 4 In-vehicle load 5 External power supply unit 51 Power receiving cable

Claims

1. An in-vehicle device that operates using an in-vehicle applied voltage, which is a voltage applied from a power supply unit mounted in a vehicle, comprising: a power receiving circuit that receives an external applied voltage, which is a voltage applied from outside the vehicle; and a control unit that controls the power receiving circuit, wherein the control unit performs a process of boosting the voltage value of the external applied voltage to the voltage value of the in-vehicle applied voltage using a boosting unit of the power receiving circuit when the external applied voltage is lower than the in-vehicle applied voltage.

2. The in-vehicle device according to claim 1, wherein the control unit calculates the ratio of the voltage value of the externally applied voltage to the voltage value of the internally applied voltage, derives a voltage boosting rate in the voltage boosting unit based on the calculated ratio, and controls the voltage boosting unit with the derived voltage boosting rate.

3. The in-vehicle device according to claim 1, wherein the power receiving circuit includes a bypass path that avoids the boost unit, and a switching unit that switches between the bypass path and a boost path to which the boost unit is connected, and the control unit switches the switching unit to the bypass path when the externally applied voltage is the same voltage value as the internally applied voltage, and switches the switching unit to the boost path when the externally applied voltage is lower than the internally applied voltage.

4. The in-vehicle device according to claim 1, comprising a power receiving terminal to which a power receiving cable for applying the externally applied voltage is connected, wherein the power receiving terminal is electrically connected to an external power supply device that applies the externally applied voltage via the power receiving cable, and the power receiving terminal is located upstream of the boosting unit in the direction of current flow from the external power supply device.

5. The in-vehicle device according to claim 4, wherein, in the direction of current flow from the external power supply device, an in-vehicle load is connected to the downstream side of the power receiving circuit, and power from the external power supply device is supplied to the in-vehicle load via the power receiving circuit.

6. The in-vehicle device according to claim 1, wherein the voltage value of the voltage applied inside the vehicle is 48V, and the voltage value of the voltage applied outside the vehicle is 12V.

7. An information processing method that causes a computer, which controls a power receiving circuit mounted on an in-vehicle device that takes an in-vehicle applied voltage (a voltage applied from a power supply unit mounted on the vehicle) as its input voltage and receives an external applied voltage (a voltage applied from outside the vehicle), to execute a process using the voltage boosting unit of the power receiving circuit to boost the voltage value of the external applied voltage to the voltage value of the in-vehicle applied voltage when the external applied voltage is lower than the in-vehicle applied voltage.

8. A program that causes a computer, which is mounted on an in-vehicle device that takes the in-vehicle applied voltage (a voltage applied from a power supply unit mounted on the vehicle) as its input voltage and controls a power receiving circuit that receives the external applied voltage (a voltage applied from outside the vehicle), to execute a process using the boosting unit of the power receiving circuit to boost the voltage value of the external applied voltage to the voltage value of the in-vehicle applied voltage when the external applied voltage is lower than the in-vehicle applied voltage.

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