Vehicle Power Supply Systems

Abstract

To provide a power supply system for a vehicle, capable of reducing power consumption in the vehicle.SOLUTION: A power supply system 100 for a vehicle supplies a power to a computer 105a, and has: a power conversion device 106 that converts an AC power into a DC power and outputs the resultant; a power controller 105c that controls the power conversion device; a first secondary battery 14; a first step-down circuit 107; a distributor 110 that has a first output end OUT1 and a second output end OUT2, that can operate in a first state where the output DC power is distributed to the first and second output ends and a second state where a power of the first secondary battery is output to the second output end, the first output end being connected with the first secondary battery and an input end of the first step-down circuit; and a second secondary battery 15 connected with an output end of the first step-down circuit, and having an output voltage lower than that of the first secondary battery. The computer can perform a first operation and a second operation, and controls a power distribution factor of the distributor in the first state and switching between the first and second states.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a vehicle power supply system mounted on a vehicle. [Background technology]

[0002] Some vehicles are equipped with a computer capable of grid computing (see, for example, Patent Document 1). In the example of Patent Document 1, when a user turns off the engine or power of the vehicle, a signal indicating that the vehicle is able to participate in grid computing is sent to a management server. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-160661 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, almost no consideration is given to power consumption management (particularly reduction of power consumption) of the device.

[0005] An object of the present disclosure is to reduce power consumption in vehicles. [Means for solving the problem]

[0006] A first aspect is a vehicle power supply system that supplies power to a computer, comprising: a power conversion device that converts AC power into DC power and outputs the DC power; a power control unit that controls the power conversion device; a first secondary battery; a first step-down circuit; a distributor having first and second output terminals and operable in a first state in which the DC power output by the power conversion device is distributed to the first and second output terminals, and a second state in which the power of the first secondary battery is output to the second output terminal, the first output terminal being connected to the first secondary battery and an input terminal of the first step-down circuit; and a second secondary battery that is connected to the output terminal of the first step-down circuit and has a lower output voltage than the first secondary battery, wherein the computer: It performs grid computing, The vehicle power supply system is capable of a first operation using power supplied to the second output terminal of the distributor, and a second operation using power supplied from the second secondary battery, and is characterized by controlling the power distribution rate of the distributor in the first state and switching between the first and second states.

[0007] In the first aspect, the computer can operate the distributor in the second state to supply power from the first secondary battery to the computer without activating the power converter and the power control unit, thereby reducing power consumption in the vehicle.

[0008] A second aspect is a computer system according to the first aspect, further comprising a second step-down circuit having an input terminal connected to the second output terminal of the distributor, and the computer being connected to the output terminal of the second step-down circuit.

[0009] In the second aspect, the voltage stepped down to the computer's input voltage is output to the wiring connecting the computer and the second step-down circuit. Therefore, compared to when the voltage stepped down to the computer's input voltage is output to a distributor, it is easier to reduce power consumption by shortening the wiring through which the voltage stepped down to the computer's input voltage is output.

[0010] A third aspect is the vehicle power supply system of the second aspect, characterized in that the computer and the second step-down circuit are housed in a common housing.

[0011] In the third aspect, the current flowing between the second step-down circuit and the computer is larger than the current flowing through the input side of the second step-down circuit, but since the second step-down circuit and the computer are housed in a common housing, it is easy to reduce power consumption by shortening the wiring between the second step-down circuit and the computer. [Effects of the Invention]

[0012] According to the present disclosure, it is possible to reduce power consumption in a vehicle. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 illustrates an example of a configuration of a grid computing system according to an embodiment. [Figure 2] FIG. 1 is a diagram illustrating the concept of grid computing. [Figure 3] FIG. 1 is a block diagram illustrating an example of the configuration of a vehicle (excerpt). [Figure 4] 1 is a block diagram showing a configuration of a vehicle power supply system; [Figure 5] 10 is a table illustrating power control when a vehicle is connected to a normal charger. [Figure 6] 10 is a table illustrating power control when the vehicle is not connected to a normal charger. DETAILED DESCRIPTION OF THE INVENTION

[0014] [Embodiment] Hereinafter, a vehicle power supply system according to this embodiment will be described with reference to the drawings. The vehicle power supply system of this embodiment is mounted on a vehicle. The vehicle is connected to a grid computing system 1 (described later). Here, the grid computing system 1 will be described. Note that the same or corresponding parts in the drawings are given the same reference numerals, and their description will not be repeated.

[0015] 《Grid Computing System 1》 1 illustrates an example of the configuration of a grid computing system 1 according to this embodiment. The grid computing system 1 includes a plurality of vehicles 10, a plurality of user terminals 20, a client server 30, a facility server 40, and a management server 50.

[0016] The client server 30 is owned by a client. The client requests the management server 50 to calculate job data. Examples of such clients include companies, research institutes, and educational institutions. The facility server 40 is owned by a facility. Users visit the facility.

[0017] Users can make reservations to visit facilities. Examples of such facilities include stadiums, theaters, supermarkets, restaurants, accommodation facilities, and retail stores. The management server 50 manages the operation (job allocation, etc.) of the grid computing system 1 in which grid computing is configured. The management server 50 is owned by the operator that operates the grid computing system 1.

[0018] These components can communicate with each other via a communication network 5. Each vehicle 10 is equipped with a computing device 105. Note that the grid computing system 1 may be provided with a plurality of client servers 30. Similarly, the grid computing system 1 may be provided with a plurality of facility servers 40.

[0019] [Grid Computing] Fig. 2 is a diagram illustrating the concept of grid computing. As shown in Fig. 2, in the grid computing system 1, grid computing is configured by a plurality of computing devices 105. In the grid computing system 1, a process (grid computing process) is performed in which an available computing device 105 among the plurality of computing devices 105 processes job data.

[0020] When the computing power of the arithmetic device 105 is needed in the vehicle 10, the arithmetic device 105 enters an operating state. That is, the computing power of the arithmetic device 105 is utilized. For example, when the computing power of the arithmetic device 105 is needed for driving control of the vehicle 10, the arithmetic device 105 enters an operating state.

[0021] On the other hand, when the computing power of the computing device 105 is no longer needed in the vehicle 10, the computing device 105 is put into a stopped state. That is, in the vehicle 10, the computing power of the computing device 105 is not used.

[0022] Here, in the vehicle 10, when the computing power of the computing device 105 is not needed, the computing power of the computing device 105 is provided for grid computing processing. This makes it possible to effectively use the computing power of the computing device 105.

[0023] 〔vehicle〕 The vehicle 10 (computer system) is owned by a user. The user may drive the vehicle 10. In this example, the vehicle 10 is a four-wheeled automobile. Examples of the vehicle 10 include an electric vehicle, a plug-in hybrid vehicle, and the like.

[0024] Fig. 3 is a block diagram illustrating an example of the configuration of a vehicle (excerpt). Fig. 4 is a block diagram illustrating the configuration of a charging control unit 200 (see Fig. 3) and the like. As shown in Figs. 3 and 4, the vehicle 10 includes an actuator 11, a sensor 12, a motor 13, a battery pack 201 (including a first secondary battery 14 described below), a second secondary battery 15, an inverter circuit 16, an input unit 101, an output unit 102, a communication unit 103, a storage unit 104, a computing device 105, first and second DC / DC converters 107 and 109, a cooling device 108, the charging control unit 200, a battery control unit 202, a heater 203, an electrical system 205, a drive system / steering system 206, and a heating and cooling system 207.

[0025] The inverter circuit 16 converts the input DC voltage into an AC voltage of a predetermined frequency and a predetermined voltage and outputs the converted voltage. The output (three-phase AC voltage) of the inverter circuit 16 is supplied to a motor (motor 13) for driving the vehicle.

[0026] The voltage of the second secondary battery 15 is 12 V. The power of the second secondary battery 15 is supplied to a computer (such as a central control unit 105b described later) and the like.

[0027] The actuator 11 includes a steering actuator, a braking actuator, etc. An example of a braking actuator is a brake, and an example of a steering actuator is a steering wheel.

[0028] The sensors 12 acquire various types of information used to control the vehicle 10. Examples of the sensors 12 include an exterior camera, an interior camera, radar, a vehicle speed sensor, an acceleration sensor, a yaw rate sensor, an accelerator opening sensor, a steering sensor, and a brake oil pressure sensor. The exterior camera captures images outside the vehicle. The interior camera captures images inside the vehicle. The radar searches outside the vehicle.

[0029] The input unit 101 inputs information and data. Examples of the input unit 101 include an operation unit that is operated to input information corresponding to the operation, a camera that inputs an image showing information, and a microphone that inputs audio showing information. Examples of the operation unit include operation buttons and touch sensors of a car navigation device. The information and data input to the input unit 101 are sent to the calculation device 105.

[0030] The output unit 102 outputs information and data. Examples of the output unit 102 include a display unit that outputs an image representing information, and a speaker that outputs sound representing information. An example of a display unit is the display of a car navigation device. An example of a speaker is the speaker of a car navigation device.

[0031] The communication unit 103 transmits and receives information and data. The information and data received by the communication unit 103 are sent to the arithmetic device 105. In this embodiment, the user can instruct (send) the communication unit 103 to specify an operation mode (described later) to be used when connected to a standard charger. In this example, the user can send the instruction to the communication unit 103 from the user terminal 20 via wireless communication.

[0032] The storage unit 104 stores information and data.

[0033] The battery pack 201 includes a first secondary battery 14, a battery heater 201a, a distributor 110, and a battery case C1. The voltage of the first secondary battery 14 is several hundred volts (e.g., 200 V). Therefore, the output voltage of the second secondary battery 15 is lower than the output voltage of the first secondary battery 14. The power of the first secondary battery 14 is input to an inverter circuit 16. The first secondary battery 14 may be normally charged or quickly charged. The first secondary battery 14, battery heater 201a, and distributor 110 are housed in a common battery case C1.

[0034] The battery heater 201a is a heater for adjusting the temperature of the first secondary battery 14. The battery heater 201a receives power supply from the first secondary battery 14.

[0035] The distributor 110 will be described later.

[0036] The cooling device 108 cools the arithmetic device 105 and the first secondary battery 14. Specifically, the cooling device 108 water-cools the first secondary battery 14. The cooling device 108 also conditions the air inside the vehicle (compartment). That is, the cooling device 108 has a water-cooling function and an air-conditioning function. The cooling device 108 uses these functions to water-cool part of the arithmetic device 105 and air-cool part of it.

[0037] The cooling device 108 is equipped with a condenser, an evaporator, a chiller, a pump, etc. (all of which are not shown) to achieve water cooling and air conditioning functions. The operation of the cooling device 108 is controlled by the computing device 105.

[0038] The arithmetic device 105 includes multiple control units (computers). In this example, the arithmetic device 105 includes a video media control unit 105a, a central control unit 105b, and a driving assistance unit 105e (see FIG. 4). Note that the video media control unit 105a is a computer that constitutes the arithmetic device 105, but in FIG. 4, for convenience of illustration, the video media control unit 105a is shown independently.

[0039] Among these computers, some are allowed to participate in grid computing, and some are not. Power is supplied to the video media control unit 105a, the central control unit 105b, and the driving assistance unit 105e from the second secondary battery 15.

[0040] The video media control unit 105a (computer) is equipped with an MPU (Media Processing Unit). The MPU is a device that includes a processor that processes image data. The user may choose whether or not to install the video media control unit 105a when purchasing the vehicle 10.

[0041] The video media control unit 105a processes the video captured by the in-vehicle camera and the video captured by the external camera (image data) by causing the MPU to execute a predetermined program. By executing the program, the MPU can, for example, automatically edit the image data. Note that the video media control unit 105a may communicate with the central control unit 105b and the driving assistance unit 105e via a local area network (such as Ethernet).

[0042] Furthermore, the video media control unit 105a controls the distributor 110, which will be described later, by causing the MPU to execute a predetermined program.

[0043] The MPU is a processor with relatively high computing power. The video media control unit 105a (MPU) is allowed to participate in grid computing.

[0044] The electronic components of the video media control unit 105a are cooled by the cooling device 108. For example, certain semiconductor elements that make up the video media control unit 105a are water-cooled by the cooling device 108. The video media control unit 105a is housed in an MPU case C2 that serves as a common housing. Cool air is introduced into the MPU case C2 from the cooling device 108. In other words, the video media control unit 105a is air-cooled by the cooling device 108.

[0045] By executing the program, the video media control unit 105a is able to control the cooling device 108. The video media control unit 105a can adjust the capacity of the cooling device 108 in order to cool itself.

[0046] The central control unit 105b includes one or more central processing units (CPUs). The central control unit 105b controls the vehicle 10 while it is running by having the CPU execute a predetermined program. In principle, the central control unit 105b does not operate while the vehicle is parked.

[0047] For example, the central control unit 105b controls the actuators (motor 13) of the drive system in response to various information obtained by the sensors 12. The central control unit 105b also controls the cooling device 108 (such as controlling the air conditioning inside the vehicle). The central control unit 105b is not permitted to participate in grid computing. Note that the CPU and other components of the central control unit 105b are cooled by the cooling device 108, just like the video media control unit 105a.

[0048] The driving support unit 105e includes one or more CPUs. The CPUs execute predetermined programs to control the various functions of the preventive safety driving support. In principle, the driving support unit 105e does not operate while the vehicle is parked.

[0049] For example, the driving support unit 105e performs following-up driving of the vehicle ahead, situation evaluation related to damage mitigation braking, brake control, etc. The driving support unit 105e is not permitted to participate in grid computing.

[0050] A group of components including the second secondary battery 15, the inverter circuit 16, the first and second DC / DC converters 107, 109, the charging control unit 200, the battery pack 201, and the battery control unit 202 constitute a vehicle power supply system 100. The vehicle power supply system 100 supplies power to the motor 13, the arithmetic unit 105 including the video media control unit 105a, the electrical system 205, the drive system / steering system 206, the heating and cooling system 207, and the like.

[0051] The charging control unit 200 manages the charging of the first secondary battery 14. During normal charging, the charging control unit 200 is connected to a normal charger. The normal charger is, for example, a commercial power source. The commercial power source is, for example, a single-phase 100V or single-phase 200V AC power source.

[0052] The charging control unit 200 includes a power control unit 105c and a power conversion device 106 (DC power supply unit) as components. The power control unit 105c and the power conversion device 106 of the charging control unit 200 are housed in a common power supply case C3. The components of the charging control unit 200 may be mounted on the same board. The distributor 110 is not housed in the power supply case C3.

[0053] The power conversion device 106 is connected to a normal charger during normal charging. The power conversion device 106 converts an input AC voltage into a DC voltage and outputs the DC voltage. The operation of the power conversion device 106 is controlled by a power control unit 105c. The power conversion device 106 includes a rectifier 106a, an inverter circuit 106b, a transformer 106c, and a rectifier 106d.

[0054] The rectifier 106a (AC / DC converter) rectifies the AC voltage input from the normal charger and outputs a DC voltage. The rectifier 106a can be configured with, for example, a diode bridge circuit.

[0055] The inverter circuit 106b (DC / AC converter) converts the DC voltage output by the rectifier 106a into an AC voltage having a predetermined voltage and frequency. The output of the inverter circuit 106b is input to a transformer 106c.

[0056] The transformer 106c (booster) boosts the AC voltage output by the inverter circuit 106b. The output voltage of the transformer 106c is several hundred volts (for example, about 200V). The output of the transformer 106c is input to the rectifier 106d.

[0057] The rectifier 106d (AC / DC converter) converts the AC voltage output by the transformer 106c into a DC voltage. The output voltage of the rectifier 106d is a DC voltage (e.g., 200 V) suitable for charging the first secondary battery 14. The rectifier 106d can be configured, for example, with a diode bridge circuit.

[0058] The distributor 110 has first and second input terminals IN1 and IN2 and first and second output terminals OUT1 and OUT2. The distributor 110 is controlled (instructed) by the video media control unit 105a.

[0059] The distributor 110 can be configured with a semiconductor switch, a relay, or a DC / DC converter. In this embodiment, the distributor 110 is configured with a DC / DC converter. The distributor 110 can control not only whether or not to supply power, but also the amount of power to be supplied.

[0060] An output terminal of the power conversion device 106 (more precisely, an output terminal of the rectifier 106d) is connected to a first input terminal IN1 of the distributor 110. An output terminal of the first secondary battery 14 is connected to a second input terminal IN2 of the distributor 110.

[0061] A first output terminal OUT1 of the distributor 110 is connected to the first secondary battery 14 and the input terminal of the second DC / DC converter 109. The distributor 110 can control on / off of power supply from the power conversion device 106 to the first secondary battery 14. This on / off control is performed by the video media control unit 105a. A second output terminal OUT2 of the distributor 110 is connected to the input terminal of the first DC / DC converter 107. The distributor 110 can operate in a first state in which it distributes DC power output by the power conversion device 106 from the first input terminal IN1 to the first and second output terminals OUT1 and OUT2, and a second state in which it outputs power from the first secondary battery 14 from the second input terminal IN2 to the second output terminal OUT2. In other words, the distributor 110 can selectively supply power from the power conversion device 106 or power from the first secondary battery 14 to the first DC / DC converter 107. The power distribution ratio in the first state of the distributor 110 and the switching between the first and second states are controlled by the video media control unit 105a. The control of the power distribution ratio in the first state is performed by switching between three states, for example: a state in which power is supplied only to the first output terminal OUT1; a state in which power is supplied to both the first and second output terminals OUT1 and OUT2; and a state in which power is supplied only to the second output terminal OUT2. The power distribution ratio to the first and second output terminals OUT1 and OUT2 may also be controlled more finely.

[0062] The first DC / DC converter 107 is a step-down circuit (second step-down circuit). The first DC / DC converter 107 has multiple output terminals. The output voltage of each output terminal is 12 V. The first DC / DC converter 107 can control the amount of power at each output terminal. The power at the output terminal of the first DC / DC converter 107 may be zero (i.e., off state). The operation of the first DC / DC converter 107 is controlled by the video media control unit 105a.

[0063] One device (power supply destination) is connected to one output terminal of the first DC / DC converter 107. In this embodiment, the power destinations of the first DC / DC converter 107 are the video media control unit 105a, the power control unit 105c, and the battery control unit 202. The first DC / DC converter 107 is housed in a common MPU case C2 together with the video media control unit 105a. The first DC / DC converter 107 may be mounted on the same board as the video media control unit 105a, or may be mounted on a different board. In this way, the video media control unit 105a is connected to the output terminal of the first DC / DC converter 107 and the second secondary battery 15, so that the video media control unit 105a can perform a first operation using power supplied to the second output terminal OUT2 of the distributor 110 and a second operation using power supplied from the second secondary battery 15.

[0064] The second DC / DC converter 109 is a step-down circuit (first step-down circuit). The first secondary battery 14 is connected to the input terminal of the second DC / DC converter 109. The output voltage of the output terminal of the second DC / DC converter 109 is 12 V. The second DC / DC converter 109 is capable of controlling the on / off of its output. The second secondary battery 15 is connected to the output terminal of the second DC / DC converter 109.

[0065] The battery control unit 202 includes a CPU. The CPU executes a predetermined program to monitor the first secondary battery 14, control relays in the battery pack 201, and perform other operations. For example, the battery control unit 202 checks and diagnoses the temperature, current, voltage, and other parameters of the cells of the first secondary battery 14. The battery control unit 202 also controls the second DC / DC converter 109. Specifically, the battery control unit 202 switches the output of the second DC / DC converter 109 on and off. The battery control unit 202 is not housed in any of the battery case C1, the MPU case C2, or the power supply case C3.

[0066] The heater 203 is a heater for air conditioning inside the vehicle. The heater 203 receives power from the first secondary battery 14. An electrical system 205, a drive system / steering system 206, a heating / cooling system 207, etc. are electrical components provided in the vehicle 10. These electrical components receive power from the second secondary battery 15.

[0067] <<Example of operation (power control)>> Power control in the vehicle 10 (computer system) will be described for the cases where the vehicle 10 is connected to a normal charger and where the vehicle 10 is not connected to a normal charger.

[0068] <When vehicle 10 is connected to a standard charger> When vehicle 10 is connected to a standard charger, power is supplied from the standard charger to charging control unit 200 (more precisely, power conversion device 106). When vehicle 10 is connected to a standard charger, the following three modes can be selected as the operating mode:

[0069] (1) A mode (first mode) in which the first secondary battery 14 is charged but the device does not participate in grid computing.

[0070] (2) A mode (second mode) in which both charging of the first secondary battery 14 and participation in grid computing are performed.

[0071] (3) A mode in which the first secondary battery 14 is not charged and the device participates in grid computing (third mode).

[0072] FIG. 5 is a table explaining power control when vehicle 10 is connected to a standard charger (abbreviated as "charger" in the figure). In FIG. 5, OBC (On Board Charger) refers to the charging control unit 200 (the same applies to other figures). Also, in FIG. 5, "◯" means that the corresponding device is operating, and "×" means that the corresponding device is stopped. Also, "MPU calculation" means that the video media control unit 105a participates in grid computing (the same applies to other figures).

[0073] 5, "high" for "power state of second secondary battery" means that second secondary battery 15 is in a power state where it can supply power to video media control unit 105a (MPU). "low" for "power state of second secondary battery" means that second secondary battery 15 is in a power state where it cannot supply power to video media control unit 105a (MPU).

[0074] [First mode] In the first mode, the first secondary battery 14 is charged. In the first mode, power is supplied to the first secondary battery 14 using power from a normal charger. Specifically, in the first mode, the video media control unit 105a controls the distributor 110 to operate in a first state in which the distributor 110 distributes the DC power output by the power conversion device 106 from the first input terminal IN1 to the first and second output terminals OUT1 and OUT2. The video media control unit 105a also controls the distribution ratio of the distributor 110 so that the output of the power conversion device 106 is supplied to the first secondary battery 14.

[0075] In the first mode, the charging control unit 200 operates (see FIG. 5). In other words, power is supplied to the charging control unit 200. In the first mode, the video media control unit 105a controls the distributor 110 to stop the power supply to the second output terminal OUT2, i.e., the first DC / DC converter 107.

[0076] [Second mode] - Charging the first secondary battery 14 - In the second mode, the first secondary battery 14 is charged. In the second mode, power is supplied to the first secondary battery 14 using power from a normal charger. Specifically, the video media control unit 105a controls the distributor 110 to operate in a first state in which the DC power output by the power conversion device 106 is distributed from the first input terminal IN1 to the first and second output terminals OUT1 and OUT2. The video media control unit 105a also controls the distribution ratio of the distributor 110 so that the output of the power conversion device 106 (the output of the rectifier 106d) is supplied to the first secondary battery 14.

[0077] As a result, the first secondary battery 14 is charged.

[0078] -Power supply to MPU- In the second mode, power is supplied to the video media control unit 105a (MPU). In the second mode, the power supply source to the video media control unit 105a varies depending on whether the power state of the second secondary battery 15 (12V battery) is "high" or "low." For example, when the power state of the second secondary battery 15 is "high," power is supplied directly from the second secondary battery 15 to the video media control unit 105a. Then, the video media control unit 105a performs a second operation using the power supplied from the second secondary battery 15.

[0079] When the power state of second secondary battery 15 is "low," power obtained from the normal charger is used to supply power to video media control unit 105a. Specifically, video media control unit 105a controls distributor 110 to operate in a first state in which DC power output by power conversion device 106 is distributed from first input terminal IN1 to first and second output terminals OUT1 and OUT2. In addition, video media control unit 105a controls the distribution ratio of distributor 110 so that the output of power conversion device 106 is input not only to first output terminal OUT1 but also to second output terminal OUT2, i.e., first DC / DC converter 107.

[0080] The first DC / DC converter 107 reduces the output voltage (DC voltage) of the power conversion device 106 to a voltage suitable for the video media control unit 105a. The first DC / DC converter 107 supplies the DC voltage generated in this manner to the video media control unit 105a. This enables the video media control unit 105a to participate in grid computing. At this time, the video media control unit 105a performs a first operation using the power supplied to the second output terminal OUT2 of the distributor 110.

[0081] As described above, in the second mode, the charging control unit 200 (OBC) operates. In other words, power is supplied to the charging control unit 200. In addition, in the second mode, power is also supplied to the video media control unit 105a and the battery control unit 202.

[0082] [Third mode] In the third mode, the first secondary battery 14 is not charged. In the third mode, power is supplied to the video media control unit 105a and the devices that operate it. In the third mode, the power supply source to the video media control unit 105a also differs depending on whether the power state of the second secondary battery 15 is "high" or "low."

[0083] When the power state of second secondary battery 15 is "high," power is supplied from second secondary battery 15 to video media control unit 105a. Therefore, video media control unit 105a performs a second operation using power supplied from second secondary battery 15. When the power state of second secondary battery 15 is "low," power obtained from the normal charger is used to supply power to video media control unit 105a.

[0084] Specifically, when the power state of the second secondary battery 15 is "low," the video media control unit 105a controls the distributor 110 so that the output of the power conversion device 106 is input from the first input terminal IN1 to the second output terminal OUT2, i.e., to the first DC / DC converter 107. The first DC / DC converter 107 steps down the output voltage (direct current voltage) of the power conversion device 106 to a voltage suitable for the video media control unit 105a.

[0085] The first DC / DC converter 107 supplies the DC voltage generated in this manner to the video media control unit 105a. This enables the video media control unit 105a to participate in grid computing. At this time, the video media control unit 105a performs a first operation using the power supplied to the second output terminal OUT2 of the distributor 110.

[0086] In the third mode, when the power state of the second secondary battery 15 is "low," the charging control unit 200 operates. Also, when the power state of the second secondary battery 15 is "low," power is supplied to the first DC / DC converter 107. The video media control unit 105a controls the distributor 110 to operate in a first state in which the distributor 110 distributes the DC power output by the power conversion device 106 from the first input terminal IN1 to the first and second output terminals OUT1 and OUT2. Also, the video media control unit 105a controls the distribution ratio of the distributor 110 so that the output of the power conversion device 106 is supplied to the second output terminal OUT2, i.e., the first DC / DC converter 107.

[0087] On the other hand, when the power state of the second secondary battery 15 is "high", in principle, the operation of the charging control unit 200 is not necessary. However, for the sake of power management, the power control unit 105c of the charging control unit 200 may operate. In other words, there may be cases where a part of the charging control unit 200 operates.

[0088] <When vehicle 10 is not connected to a standard charger> When vehicle 10 is traveling, it is not connected to a standard charger. Also, when vehicle 10 is parked, it may not be connected to a standard charger. When vehicle 10 is not connected to a standard charger, vehicle 10 can select from the following three operating modes (modes 4 to 6).

[0089] (1) A mode (fourth mode) in which the second secondary battery 15 (12V battery) is charged but does not participate in grid computing.

[0090] (2) A mode (fifth mode) in which both the second secondary battery 15 is charged and participation in grid computing is performed.

[0091] (3) A mode in which the second secondary battery 15 is not charged and the device participates in grid computing (sixth mode).

[0092] Fig. 6 is a table explaining power control when vehicle 10 is not connected to a standard charger. In Fig. 6, OBC also represents charging control unit 200. In Fig. 6, "◯" also represents a state in which the device corresponding to this symbol is operating, and "×" represents a state in which the device corresponding to this symbol is stopped.

[0093] [Fourth mode] In the fourth mode, the second secondary battery 15 is charged using the power of the first secondary battery 14. In the fourth mode, the battery control unit 202 operates the second DC / DC converter 109 (first step-down circuit).

[0094] The second DC / DC converter 109 steps down the DC voltage (for example, 200 V) supplied from the first secondary battery 14 to a DC voltage (for example, 12 V) suitable for charging the second secondary battery 15. The DC voltage generated by the second DC / DC converter 109 is supplied to the second secondary battery 15. In this way, the second secondary battery 15 is charged.

[0095] As described above, in the fourth mode, the battery control unit 202 and the battery pack 201 operate. In the fourth mode, the power supply to the charging control unit 200 can be stopped.

[0096] [5th ​​mode] In the fifth mode, the second secondary battery 15 is charged using the power of the first secondary battery 14. In the fifth mode, the same control as in the fourth mode is performed to charge the second secondary battery 15. That is, in the fifth mode, the battery control unit 202 also operates the second DC / DC converter 109 (first step-down circuit). The second DC / DC converter 109 supplies the generated DC voltage to the second secondary battery 15.

[0097] In the fifth mode, the power supply source to the video media control unit 105a differs depending on whether the power state of the second secondary battery 15 is "high" or "low." When the power state of the second secondary battery 15 is "high," power from the second secondary battery 15 is directly supplied to the video media control unit 105a. Therefore, the video media control unit 105a performs a second operation using power supplied from the second secondary battery 15.

[0098] When the power state of the second secondary battery 15 is "low," the power of the first secondary battery 14 is used to supply power to the video media control unit 105a. Specifically, the video media control unit 105a controls the distributor 110 to operate in a second state in which the power of the first secondary battery 14 is sent from the second input terminal IN2 to the second output terminal OUT2, i.e., to the first DC / DC converter 107. In other words, the video media control unit 105a controls the distributor 110 so that the output of the first secondary battery 14 is input to the first DC / DC converter 107.

[0099] The first DC / DC converter 107 steps down the DC voltage input from the first secondary battery 14 to a DC voltage suitable for the operation of the video media control unit 105a. The DC voltage generated by the first DC / DC converter 107 in this manner is supplied to the video media control unit 105a. This enables the video media control unit 105a to participate in grid computing. At this time, the video media control unit 105a performs a first operation using the power supplied to the second output terminal OUT2 of the distributor 110.

[0100] In the fifth mode, there is no need to operate the charging control unit 200 to charge the second secondary battery 15. When the power state of the second secondary battery 15 is "high," there is no need to operate the charging control unit 200 to supply power to the video media control unit 105a.

[0101] In the fifth mode, when the power state of the second secondary battery 15 is "low", the distributor 110 of the video media control unit 105a controls the video media control unit 105a to supply power using the power of the first secondary battery 14. When the power state of the second secondary battery 15 is "low", the charging control unit 200 does not operate.

[0102] [6th mode] In the sixth mode, power is supplied to the video media control unit 105a and the devices for operating it. Even in the sixth mode, the power supply source to the video media control unit 105a differs depending on whether the power state of the second secondary battery 15 is "high" or "low." When the power state of the second secondary battery 15 is "high," power from the second secondary battery 15 is directly supplied to the video media control unit 105a. Therefore, the video media control unit 105a performs a second operation using power supplied from the second secondary battery 15.

[0103] When the power state of the second secondary battery 15 is "low," the first secondary battery 14 is used to supply power to the video media control unit 105a. Specifically, the video media control unit 105a controls the distributor 110 to operate in a second state in which power from the first secondary battery 14 is sent from the second input terminal IN2 to the second output terminal OUT2, i.e., to the first DC / DC converter 107. In other words, the video media control unit 105a controls the distributor 110 so that the output of the first secondary battery 14 is input to the first DC / DC converter 107 (second step-down circuit).

[0104] The first DC / DC converter 107 steps down the DC voltage input from the first secondary battery 14 to a DC voltage suitable for the operation of the video media control unit 105a. The DC voltage generated by the first DC / DC converter 107 in this manner is supplied to the video media control unit 105a. This enables the video media control unit 105a to participate in grid computing. At this time, the video media control unit 105a performs a first operation using the power supplied to the second output terminal OUT2 of the distributor 110.

[0105] Effects of this embodiment As described above, in this embodiment, power distribution control to the secondary batteries 14, 15 and the video media control unit 105a (MPU) is possible. When the vehicle 10 is not connected to a standard charger, it is not necessary to activate the charging control unit 200. In particular, since the distributor 110 can be operated in the second state by control of the video media control unit 105a, when the vehicle 10 is not connected to a standard charger and the video media control unit 105a is allowed to participate in grid computing, power from the first secondary battery 14 can be supplied to the video media control unit 105a when the power state of the second secondary battery 15 is "low" without activating the charging control unit 200. In other words, the components of the charging control unit 200 are activated as needed. According to this embodiment, it is possible to reduce power consumption in the vehicle 10.

[0106] Furthermore, when the vehicle 10 is connected to a normal charger and in a mode (third mode) in which the first secondary battery 14 is not charged and the vehicle 10 participates in grid computing, if the power state of the second secondary battery 15 is "low," the distributor 110 is controlled by the video media control unit 105a, so there is no need to activate the battery control unit 105a to control the distributor 110. This makes it possible to reduce power consumption in the vehicle 10.

[0107] [Other embodiments] The computer participating in grid computing is not limited to the video media control unit 105a (first computer). In addition to the video media control unit 105a, other computers may also be allowed to participate in grid computing.

[0108] In the first to third modes, some or all of the processing that was previously performed by power control unit 105c may be performed by video media control unit 105a. For example, if video media control unit 105a performs all of the processing that was previously performed by power control unit 105c, power control unit 105c may not be provided.

[0109] Furthermore, the first DC / DC converter 107 may not be provided, and the voltage step-down function of the first DC / DC converter 107 may be provided in the distributor 110 .

[0110] The vehicle power supply system 100 may be used in an MPU connected mode in which the first DC / DC converter 107 and the video media control unit 105a are connected to the battery pack 201, and in an MPU disconnected mode in which the first DC / DC converter 107 and the video media control unit 105a are not connected to the battery pack 201. In this case, the video media control unit 105a may control the distributor 110 in the MPU connected mode, while the battery control unit 202 may control the distributor 110 in the MPU disconnected mode.

[0111] The above-described embodiments may be implemented in appropriate combinations. The above-described embodiments are essentially preferred examples and are not intended to limit the scope of the technology disclosed herein, its applications, or its uses. [Explanation of symbols]

[0112] 100 Vehicle power supply system 14 1st secondary battery 15 2nd secondary battery 105a Video Media Control Unit (Computer) 105c Power control unit 106 Power conversion device 107 First DC / DC converter (second step-down circuit) 109 Second DC / DC converter (first step-down circuit) 110 Distributor C2 MPU case (chassis) OUT1 First output terminal OUT2 Second output terminal

Claims

1. In a vehicle power supply system for supplying power to a computer, a power conversion device that converts AC power into DC power and outputs the DC power; a power control unit that controls the power conversion device; a first secondary battery; a first step-down circuit; a distributor having first and second output terminals, operable in a first state in which the DC power output by the power conversion device is distributed to the first and second output terminals, and in a second state in which the power of the first secondary battery is output to the second output terminal, the first output terminal being connected to the first secondary battery and an input terminal of the first step-down circuit; a second secondary battery connected to an output terminal of the first step-down circuit and having an output voltage lower than that of the first secondary battery; The computer performs grid computing, is capable of a first operation using power supplied to the second output terminal of the distributor, and a second operation using power supplied from the second secondary battery, and controls the power distribution rate of the distributor in the first state and switching between the first and second states.

2. 2. The vehicle power supply system according to claim 1, a second step-down circuit having an input terminal connected to the second output terminal of the divider; The vehicle power supply system is characterized in that the computer is connected to an output terminal of the second step-down circuit.

3. 3. The vehicle power supply system according to claim 2, 10. A vehicle power supply system, comprising: a power supply circuit for a vehicle; a power supply for a vehicle; a power supply for a vehicle;

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