Power supply device, power supply system, and control method

Abstract

The present invention addresses the problem of providing a power supply device, a power supply system, and a control method that achieve efficient power supply to a plurality of connected devices. [Solution] A power supply device (1) is provided with: a power supply unit (21) capable of supplying power to a plurality of connected devices (DV); and a control unit (20) having a function for negotiating before starting to supply power to the devices (DV) and determining the distribution of power to be supplied to the respective devices (DV) within a range that does not exceed an upper limit value. The control unit (20) redetermines the distribution of the power to be supplied to the plurality of connected devices (DV) in response to the reduction of the power requested in the request when a request for reducing the power to be supplied to the devices (DV) is received after the supply of the power is started in accordance with the negotiated distribution.

Description

Technical Field

[0001] The present invention relates to a power supply device, a power supply system and a control method, and is particularly applicable to a power supply device configured to supply power to a plurality of devices simultaneously, a power supply system including the power supply device, and a control method performed by the power supply device. Background Art

[0002] In the past, there have been known power supply devices that can connect to multiple devices and can supply power to each of the multiple devices. In particular, in USB PD (Power Delivery), which is a charging specification of USB-TypeC, a large amount of power can be supplied. Taking advantage of this, power supply devices that support USB PD are becoming increasingly popular. The power supply devices have multiple connectors and are configured to supply power to multiple devices connected to the multiple connectors.

[0003] Regarding a power supply device that can supply power to each of a plurality of devices, the following technology is disclosed in Patent Document 1. That is, the hub 10 of Patent Document 1 is a power supply device that is connected to an electronic device 7 (device) and a mobile device 8 (device), and supplies power to these devices and charges these devices. In the hub 10, there are provided a power module 12 that supplies power to these devices, and a power distribution control circuit 13 that measures the power value (power value) of the power supplied by the power module 12. In addition, when supplying power to the electronic device 7 and the mobile device 8, the hub 10 adjusts the power supplied to the electronic device 7 and the power supplied to the mobile device 8 in such a way that the power value measured by the power distribution control circuit 13 does not exceed the upper limit value that can be stably supplied by the power module 12. Patent Document 1 discloses the above technology. According to Patent Document 1, it is possible to achieve appropriate active distribution of the total power output of the power supply device.

[0004] In addition, the following technology is disclosed in Patent Document 2. That is, the main controller 124 on the device side obtains charger capability information related to the charger capability from the USB charger 110 (power supply device), and sets the optimal power supply level based on the information and its own device charging capability information. Patent Document 2 discloses the above technology. According to Patent Document 2, mismatching of charging / power supply levels can be suppressed.

[0005] Prior art literature:

[0006] Patent Literature:

[0007] Patent Document 1: Japanese Patent Application Publication No. 2018-206394

[0008] Patent Document 2: Japanese Patent Application Publication No. 2019-109898 Summary of the invention

[0009] Problems to be solved by the invention:

[0010] Here, in the case of supplying power from a power supply device to multiple connected devices, as disclosed in Patent Document 1, power is usually supplied according to the determined distribution based on the distribution of power supplied to each device. In addition, in a power supply device that can supply power to multiple devices and can communicate with each device, the following processing has been performed on the distribution of power in the past. Among them, a device that supports USB PD is equivalent to such a power supply device. That is, when supplying power to multiple connected devices, a negotiation is performed between the power supply device and the device before the power supply to the device starts. Then, the power supply device determines the distribution of power according to the result of the negotiation. Thereafter, unless the device is plugged in or unplugged or the power supply of the device is turned on / off, the power supply is reset once and the negotiation is performed again, the power supply device does not change the distribution. On the other hand, after the power supply to multiple devices starts, each device sends a request to the power supply device to change the power supply to itself when a reason occurs that the power supply to itself should be changed. The above processing has been performed in the past.

[0011] The prior art for performing the above processing has the following problems. For example, assume the following situation: the first device and the second device are connected to the power supply device, and power is being supplied according to the distribution based on negotiation. In this situation, if a reason occurs in the second device that requires a reduction in the supplied power, the second device sends a request to reduce the power, and the power supply device reduces the power supplied to the second device according to the request. As a result, the power supply capacity of the power supply device can be sufficient to reduce the amount of power supplied to the second device, but on the other hand, this state will continue, becoming a major factor hindering efficient power supply.

[0012] The present invention has been made to solve such a problem, and an object of the present invention is to realize efficient power supply to a plurality of connected devices in a power supply device that can supply power to a plurality of devices and can communicate with each device.

[0013] Means used to solve the problem:

[0014] In order to solve the above-mentioned problems, the power supply device involved in the present invention comprises: a power supply unit capable of supplying power to a plurality of connected devices; and a control unit having: a function of controlling the power supplied by the power supply unit; a function of communicating with the connected devices; and a function of communicating and negotiating with the devices before starting to supply power to the devices when supplying power to the plurality of devices, and determining the distribution of power supplied to each device within a range where the total of the supplied power does not exceed an upper limit value. In addition, after starting to supply power to each of the plurality of connected devices according to the distribution based on the negotiation, in the case where a request is received from one device to reduce the power supplied to one device, the control unit reflects the reduction of the power requested in the request and re-determines the distribution of power supplied to the plurality of connected devices.

[0015] Effect of the invention:

[0016] According to the present invention constructed as described above, after power supply starts according to the allocation based on negotiation, when a request for reducing the power supply is issued from one of the multiple connected devices, the reduction of the power requested in the request is reflected and the allocation of power supplied to the multiple connected devices is re-determined. Therefore, it is possible to determine the new power allocation without waiting for the next negotiation to be performed, and power can be supplied efficiently. That is, according to the present invention, for a power supply device that can supply power to multiple devices and can communicate with each device, efficient power supply to multiple connected devices is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a block diagram showing an example of a functional configuration of a power supply device according to an embodiment.

[0018] Figure 2 This is a diagram showing a state in which the power supply device supplies power.

[0019] Figure 3 This is a flowchart showing an operation example of the power supply system.

[0020] Figure 4 This is a diagram for explaining a conventional problem.

[0021] Figure 5 This is a diagram for explaining a conventional problem.

[0022] Figure 6 This is a flowchart showing an operation example of the power supply system.

[0023] Figure 7 This is a diagram showing the relationship between the upper limit value of the supplied electric power and the distribution of electric power.

[0024] Description of reference numerals:

[0025] 1 Power supply device

[0026] 21st Equipment (equipment)

[0027] 3.2nd Equipment (Equipment)

[0028] 4 Power supply system

[0029] 20 Control Department

[0030] 21 Power supply unit

[0031] DV equipment DETAILED DESCRIPTION

[0032] Hereinafter, one embodiment of the present invention will be described based on the drawings. Figure 1 This is a diagram showing an example of the functional configuration of the power supply device 1 involved in the present embodiment together with the first device 2 and the second device 3 connected to the power supply device 1. The power supply device 1 and one or more devices connected thereto constitute a power supply system 4. The power supply system 4 complies with USB Type-C, and the power supply device 1 and the first device 2 are connected via a USB Type-C cable 5 (hereinafter referred to as the "first cable 5"), and the power supply device 1 and the second device 3 are connected via a USB Type-C cable 6 (hereinafter referred to as the "second cable 6").

[0033] The power supply device 1 involved in the present embodiment is a device mounted on a vehicle. The power supply device 1 is mounted on, for example, a car navigation, a car audio, or other vehicle-mounted devices. Among them, the power supply device 1 can be mounted on an adapter or can be an independent device. The power supply device 1 is a device that complies with USB PD (Power Delivery) and has the function of supplying power in accordance with USB PD. In particular, the power supply device 1 has two (plural) power supply device first connectors 8 and power supply device second connectors 9, and can simultaneously supply power to each of the two devices DV connected to the power supply device first connector 8 and the power supply device second connector 9. In addition, the device DV means a device that may become the object of power supply by the power supply device 1. The device DV that receives the power supply charges a specified battery or supplies power to a load. In the following, the situation where the device DV is sometimes connected to the power supply device first connector 8 or the power supply device second connector 9 of the power supply device 1 via a cable is simply expressed as "the device DV is connected to the power supply device 1".

[0034] In the present embodiment, the first connector 8 and the second connector 9 of the power supply device are sockets supporting USB Type-C, and are configured to include a VBUS terminal for supplying a bus voltage, a GND terminal related to a ground voltage, and a CC (Configuration Channel) port. Hereinafter, the power supply line corresponding to the first connector 8 of the power supply device (a line for supplying power to the device DV connected to the first connector 8 of the power supply device) is referred to as the first power supply line 10. In addition, the power supply line corresponding to the second connector 9 of the power supply device (a line for supplying power to the device DV connected to the second connector 9 of the power supply device) is referred to as the second power supply line 11. In addition, the CC line corresponding to the first connector 8 of the power supply device (a communication line for communicating with the device connected to the first connector 8 of the power supply device) is referred to as the first CC line 12. In addition, the CC line corresponding to the second connector 9 of the power supply device (a communication line for communicating with the device connected to the second connector 9 of the power supply device) is referred to as the second CC line 13.

[0035] The first device 2 is an electronic device. The type of the electronic device as the first device 2 is not limited. The first device 2 is, for example, a notebook personal computer, a tablet terminal (including a smartphone), a portable game console, or a wearable terminal (but not limited thereto).

[0036] The second device 3 is an electronic device. The second device 3 may be any type of electronic device like the first device 2, but in this embodiment, the second device 3 is a smartphone. A user riding in a vehicle equipped with the power supply device 1 can connect his or her smartphone to the power supply device 1 and charge the smartphone.

[0037] like Figure 1 As shown, the power supply device 1 includes a control unit 20 , a power supply unit 21 , and a communication unit 22 .

[0038] The control unit 20 is a controller supporting USB PD and USB Type-C, and includes an IC in which various circuits including a processor are integrated. The control unit 20 reads and executes a program stored in a predetermined memory by the processor, and performs processing through the cooperation of hardware and software.

[0039] The communication unit 22 includes a transceiver for communicating via the first CC line 12 and the second CC line 13, and communicates with the device DV under the control of the control unit 20. In the following, it is assumed that the communication unit 22 appropriately performs the communication between the power supply device 1 and the device DV, and the detailed description of the communication itself is omitted. The control unit 20 has a function of communicating with each device DV connected to the power supply device 1 via the communication unit 22.

[0040] The power supply unit 21 includes a power supply circuit including a DC / DC converter, a switching element for switching the first power supply line 10 and the second power supply line 11, and other elements (such as a necessary switch and a necessary capacitor). The power supply unit 21 receives power supply from a vehicle-mounted battery 23 as an external power source. Under the control of the control unit 20, the power supply unit 21 converts the voltage of the vehicle-mounted battery 23 as an external power source into an appropriate voltage, and supplies power to one or more devices DV connected to the power supply device 1 via the first power supply line 10 and the second power supply line 11. The vehicle-mounted battery 23 is a battery mounted on a vehicle.

[0041] The control unit 20 has a function of controlling the power supplied by the power supply unit 21. That is, the control unit 20 can control the power supply unit 21 to supply power of a specific voltage value and a specific maximum current value (upper limit of the current) to each device DV connected to the power supply device 1. In addition, with respect to the supplied power (power), the current value basically varies depending on the situation on the device DV side, but cannot exceed the maximum current value set on the power supply device 1 side. In the following, when the power supplied by the power supply device 1 is simply expressed as "current", unless otherwise specified, it means "current below the maximum current value". In addition, when the power supplied by the power supply device 1 is expressed as "current value", unless otherwise specified, it means "maximum current value" (upper limit of the current value). In addition, with respect to the power supplied by the power supply device 1, the combination of the voltage value and the current value is sometimes referred to as a "power-related value".

[0042] like Figure 1 As shown, the first device 2 includes a first device connector 25 supporting USB Type-C. The first device connector 25 is configured as a socket to which a plug can be connected. The first device connector 25 is connected to the power supply device first connector 8 of the power supply device 1 via a first cable 5. In addition, the first device 2 has a first device battery 26 as a secondary battery built in.

[0043] like Figure 1 As shown, the first device 2 includes a first device control unit 27, a first device communication unit 28, and a first device charging unit 29 as functional blocks.

[0044] The first device control unit 27 is a controller supporting USB PD and USB Type-C, and includes an IC in which various circuits including a processor are integrated. The first device control unit 27 reads and executes a program stored in a predetermined memory by the processor, and performs processing through the cooperation of hardware and software.

[0045] The first device communication unit 28 includes a transceiver for communicating via the first CC line 12, and implements communication with the power supply device 1 under the control of the first device control unit 27. In the following, it is assumed that the first device communication unit 28 appropriately performs the communication between the first device 2 and the power supply device 1, and the detailed description of the communication itself is omitted. The first device control unit 27 has a function of communicating with the control unit 20 via the first device communication unit 28.

[0046] The first device charging unit 29 includes a charging circuit including a DC / DC converter, a switching element for switching the first power supply line 10, and other elements (e.g., a necessary switch and a necessary capacitor). The first device charging unit 29 receives power from the power supply unit 21 of the power supply device 1 via the first power supply line 10. Under the control of the first device control unit 27, the first device charging unit 29 adjusts the voltage / current, adjusts the power supply timing, and other necessary processing related to charging, and charges the first device battery 26.

[0047] Although not shown in the figure, the first device 2 includes a load that receives power supply from the first device battery 26 .

[0048] As mentioned above, the second device 3 is a smart phone. Figure 1 As shown, the second device 3 includes a second device connector 30 supporting USB Type-C. The second device connector 30 is configured as a socket to which a plug can be connected. The second device connector 30 is connected to the power supply device second connector 9 of the power supply device 1 via a second cable 6. In addition, the second device 3 has a second device battery 31 as a secondary battery built in.

[0049] like Figure 1 As shown, the second device 3 includes a second device control unit 32, a second device communication unit 33, a second device charging unit 34, and a main body control unit 35 as functional blocks.

[0050] The second device control unit 32 is a controller supporting USB PD and USB Type-C, and includes an IC in which various circuits including a processor are integrated. The second device control unit 32 reads and executes a program stored in a predetermined memory by the processor, and performs processing through the cooperation of hardware and software.

[0051] The second device communication unit 33 includes a transceiver for communicating via the second CC line 13, and realizes communication with the power supply device 1 under the control of the second device control unit 32. In the following, it is assumed that the communication between the second device 3 and the power supply device 1 is appropriately performed by the second device communication unit 33, and detailed description of the communication itself is omitted. The second device control unit 32 has a function of communicating with the control unit 20 via the second device communication unit 33.

[0052] The second device charging unit 34 includes a charging circuit including a DC / DC converter, a switching element for switching the second power supply line 11, and other elements (e.g., a necessary switch and a necessary capacitor). The second device charging unit 34 receives power from the power supply unit 21 of the power supply device 1 via the second power supply line 11. Under the control of the second device control unit 32, the second device charging unit 34 adjusts the voltage / current, adjusts the power supply timing, and other necessary processing related to charging, and charges the second device battery 31.

[0053] The main body control unit 35 includes a processor. The main body control unit 35 controls various parts of the second device 3 based on the OS (Operating System) of the second device 3 as a smart phone, applications running on the OS, and other programs. The main body control unit 35 can communicate with the second device control unit 32. In addition, the main body control unit 35 can communicate with the second device control unit 32 and control the second device charging unit 34 via the second device control unit 32. In the following, the situation in which the main body control unit 35 controls the second device charging unit 34 via the second device control unit 32 is sometimes simply expressed as "the main body control unit 35 controls the second device charging unit 34". In addition, in the present embodiment, the main body control unit 35 is configured to control the second device charging unit 34 via the second device control unit 32, but it can also be configured so that the main body control unit 35 directly controls the second device charging unit 34.

[0054] Although not shown in the figure, the second device 3 includes a load that receives power supply from the second device battery 31 .

[0055] Next, an example will be described about the operation of the power supply system 4 when a plurality of devices DV are connected to the power supply device 1 and the power supply device 1 starts supplying power to the plurality of devices DV.

[0056] In the following, it is first assumed that the second device 3 is connected to the power supply device 1. If the second device 3 is connected to the power supply device 1, the control unit 20 of the power supply device 1 detects the connection. After detecting the connection, the control unit 20 communicates with the second device control unit 32 of the second device 3, and negotiates to determine the power-related value of the power supplied to the second device 3. In the negotiation, the control unit 20 receives the desired power-related value (voltage value and current value) from the second device control unit 32. Hereinafter, the power-related value desired by the device DV is referred to as the "desired power-related value". In this example, the desired power-related value of the second device 3 is set to 9V, 3A, that is, 27W. In addition, in this example, it is assumed that the control unit 20 determines the power-related value of the power supplied to the second device 3 to be 9V, 3A (27W). Hereinafter, the power-related value of the power supplied determined for the device DV is referred to as the "determined power-related value". Thereafter, the control unit 20 controls the power supply unit 21 to supply power to the second device 3 according to the determined power-related value (9 V, 3 A in this example). Figure 2 (A) indicates the state at this time.

[0057] Then, in becoming Figure 2 After the state (A), it is assumed that the first device 2 is newly connected to the power supply device first connector 8. The operation of the power supply system 4 when the first device 2 is newly connected to the power supply device first connector 8 will be described below.

[0058] Figure 3 Flowchart FA shows the control method performed by the power supply device 1, the first device 2 and the second device 3. Flowchart FB shows the control method performed by the first device 2, and flow chart FC shows the control method performed by the second device 3. Figure 3 The starting time of the flowchart shown is Figure 2 As shown in (A), only the second device 3 is connected to the power supply device 1 and the power supply device 1 is supplying 9 V and 3 A of power to the second device 3 .

[0059] As shown in the flowchart FA, the control unit 20 of the power supply device 1 monitors whether the device DV is connected to the first connector 8 of the power supply device (step SA1). In this example, it is assumed that the first device 2 is connected to the first connector 8 of the power supply device during the monitoring of step SA1. If it is detected that the first device 2 is connected to the first connector 8 of the power supply device (step SA1: yes), the control unit 20 and the first device control unit 27 of the first device 2 negotiate according to the protocol (step SA2, step SB1). In this negotiation, the control unit 20 receives the desired power-related value from the first device control unit 27. In this example, the desired power-related value of the first device 2 is set to 15V, 3A, that is, 45W.

[0060] Next, the control unit 20 performs distribution determination processing (step SA3) in consideration of the desired power-related value. The distribution determination processing is a process for determining the distribution of power supplied to the connected plurality of devices DV (in this example, the first device 2 and the second device 3). The distribution determination processing of step SA3 is described in detail below.

[0061] Here, the power supply device 1 is pre-set with an upper limit value of the power that can be supplied simultaneously to all connected devices DV (hereinafter referred to as the "supply power upper limit value"). The total value of the power supplied simultaneously to each device DV cannot exceed the supply power upper limit value. Hereinafter, the total value of the power supplied to all connected devices DV is referred to as the "supply power total value". Considering that power (power source) is supplied from the vehicle-mounted battery 23, the supply power upper limit value is appropriately set. In this example, the supply power upper limit value is set to "60W". In this case, when the supply power upper limit value is 60W, the power supply device 1 cannot supply 45W of power to the first device 2 and 27W of power to the second device 3. This is because the supply power total value (45W+27W=72W) exceeds the supply power upper limit value (60W).

[0062] In the distribution determination process of step SA3 , the control unit 20 determines the distribution of the electric power to be supplied to each of the first device 2 and the second device 3 according to the following conditions.

[0063] <Condition R1> The total value of the supplied power is set to be equal to or less than the upper limit value of the supplied power and as close to the upper limit value of the supplied power as possible.

[0064] <Condition R2> The distribution to each of the first device 2 and the second device 3 is set as close as possible to the desired power-related value of each of these devices DV. However, the voltage value of the supplied power is set to a voltage value that does not exceed the desired power-related value.

[0065] In this example, if Figure 2 As shown in (A), when the first device 2 is connected, the power supplied to the second device 3 is 9V, 3A, that is, 27W. In addition, the desired power-related value of the first device 2 is 15V, 3A. In this case, if the power-related value of the power supplied to the first device 2 is not changed, and the power-related value of the power supplied to the second device 3 is set to the desired power-related value, the total power supply value (27W+45W=72W) exceeds the power supply upper limit value (60W). Therefore, the control unit 20 does not perform such an allocation, but performs the following allocation, for example.

[0066] That is, the control unit 20 does not change the power-related value of the power supplied to the second device 3, but determines the power-related value of the power supplied to the first device 2 to be 15V, 2.2A, that is, 33W. By determining in this way, conditions R1 and R2 are satisfied. That is, with respect to condition R1, the total power supply value (33W+27W) is less than the upper limit value of the power supply (60W), and is as close to the upper limit value of the power supply (60W) as possible. In addition, with respect to condition R2, the allocation (15V, 2.2A) of the first device 2 and the allocation (9V, 3A) of the second device 3 are as close as possible to the desired power-related value (15V, 3A) of the first device 2 and the desired power-related value (9V, 3A) of the second device 3.

[0067] In addition, when determining the distribution of the supplied power, the conditions R1 and R2 are cited as the conditions that the control unit 20 follows, but the conditions are not limited to these. In particular, when there are conditions specified by the protocol, the control unit 20 will of course also determine the distribution according to the conditions. In addition, in the distribution determination process, the control unit 20 can also communicate with the first device control unit 27 and the second device control unit 32 and exchange various information. The above situation is also the same for the reallocation process described later.

[0068] In this example, in the allocation determination process, the control unit 20 Figure 2 As shown in (B), the power-related value of the power supplied to the first device 2 (i.e., the determined power-related value regarding the first device 2) is determined to be 15V, 2.2A, i.e., 33W, and the power-related value of the power supplied to the second device 3 (i.e., the determined power-related value regarding the second device 3) is determined to be 9V, 3A.

[0069] As shown in flowchart FA, after the allocation determination process of step SA3, the control unit 20 notifies the first device control unit 27 of the determined power-related value (15V, 2.2A) determined for the first device 2, and notifies the second device control unit 32 of the determined power-related value (9V, 3A) determined for the second device 3 (step SA4). Next, the control unit 20 starts supplying power to the first device 2 and the second device 3 in accordance with the allocation determined in the allocation determination process (step SA5). Specifically, the control unit 20 controls the power supply unit 21 to supply the first device 2 with power corresponding to the determined power-related value related to the first device 2, and to supply the second device 3 with power corresponding to the determined power-related value related to the second device 3.

[0070] As shown in flowchart FB, in response to the notification of step SA4 , first device control unit 27 controls first device charging unit 29 to start charging first device battery 26 based on the power supplied from power supply device 1 .

[0071] As shown in flowchart FC, in response to the notification in step SA4 , the second device control unit 32 controls the second device charging unit 34 to start charging the second device battery 31 based on the power supplied from the power supply device 1 .

[0072] As described above, the control unit 20 involved in this embodiment has the following functions: when supplying power to multiple devices DV, it communicates and negotiates with the devices before starting to supply power to the devices DV, and determines the distribution of power supplied to each device DV within the range where the total power supplied does not exceed an upper limit value.

[0073] Next, the operation of the power supply system 4 will be described when a cause for reducing the supplied power occurs in a certain device DV while the power supply device 1 is supplying power to a plurality of devices DV.

[0074] Prior to describing the operation, conventional problems related to the power supply device supplying power to a plurality of devices will be described. Figure 4 is a diagram used to illustrate a conventional problem. Figure 4 As shown in (A), the following state is set: the first device X2 and the second device X3 are connected to the power supply device X1, and power is being supplied to the first device X2 and the second device X3 according to the distribution based on negotiation. Figure 2 The same as (B) is assumed that 15V, 2.2A, or 33W of power is supplied to the first device X2, and 9V, 3A, or 27W of power is supplied to the second device X3. In addition, the upper limit of the power supplied by the power supply device X1 is set to 60W.

[0075] Figure 5 (A) is a diagram showing the relationship between the upper limit of the supplied power and the distribution of power in this situation. Figure 5 As shown in (A), in this situation, the total power supply value is equal to the power supply upper limit value, and efficient power supply is achieved.

[0076] Furthermore, unless the power supply is reset once and the negotiation is not performed again, such as when a device is plugged in or unplugged or the power of the device is turned on or off, the conventional power supply device X1 does not change the distribution of power.

[0077] In this situation, if a reason occurs in the second device X3 that requires a reduction in the power supply, the second device X3 sends a request to the power supply device X1 to reduce the power. In this example, the request is to reduce the power from 9V, 3A to 5V, 3A. In accordance with the request, the power supply device X1 reduces the power supplied to the second device X3 from 9V, 3A to 5V, 3A (see Figure 4 As a result, the following occurs.

[0078] Figure 5 (B) is a diagram showing the relationship between the upper limit of the power supply and the power distribution after the power is reduced based on the request. If the power supply to the second device X3 is reduced based on the request, the power-related value determined for the second device X3 becomes 5V, 3A, or 15W. As a result, Figure 5 As shown in (B), a state of 12W surplus is generated in the power supply capacity of the power supply device X1 in accordance with the reduction in the amount of power supplied to the second device X3. This surplus is originally the power that the power supply device X1 can supply, and the state of generating this surplus can be said to be a state in which efficient power supply is not achieved. In addition, unless the power supply is reset once and negotiated again, such as when the device is plugged in or unplugged or the power supply of the device is turned on / off, the state of generating surplus cannot be eliminated.

[0079] As described above, there has been a problem in the past that if the power supplied to the device is reduced based on a request, surplus power (power that could have been supplied but was not supplied) is generated, hindering efficient power supply. To solve the above conventional problems, the power supply system 4 involved in this embodiment performs the following processing.

[0080] Figure 6 It is a flowchart showing the operation of the power supply device 1, the first device 2, and the second device 3. Flowchart FD shows the control method performed by the power supply device 1, flowchart FE shows the control method performed by the first device 2, flowchart FF shows the control method performed by the second device control unit 32 of the second device 3, and flowchart FG shows the control method performed by the main body control unit 35 of the second device 3. Figure 6 The starting time of the flowchart is Figure 3 The moment when the processing of the flowchart ends. Therefore, at this starting moment, Figure 2 (B) shows a state where the first device 2 and the second device 3 are connected to the power supply device 1 , 15 V and 2.2 A of power are being supplied to the first device 2 , and 9 V and 3 A of power are being supplied to the second device 3 .

[0081] Figure 7 (A) is a diagram showing the relationship between the upper limit value of the supplied power and the distribution of the power in this state. Figure 7 The content of (A) and Figure 5 In this state, the upper limit value of the supplied power is consistent with the total value of the supplied power, achieving efficient power supply.

[0082] In addition, Figure 6At the start time of the flowchart of , it is assumed that the charging rate of the second device battery 31 of the second device 3 is less than 80%. Here, the main body control unit 35 has the following functions. That is, regarding the charging of the second device battery 31, when the charging rate is less than 80%, the main body control unit 35 controls the second device charging unit 34 to charge the second device battery 31 at 9V. In addition, there is also a situation where power above 9V cannot be supplied due to reasons on the power supply side (source side). In this case, the main body control unit 35 charges the second device battery 31 at a lower voltage. Then, when the charging rate changes from a state below 80% to more than 80%, the main body control unit 35 controls the second device charging unit 34 to charge the second device battery 31 at 5V on the basis of executing the required processing. The main body control unit 35 has the above functions. Such a function of reducing the charging voltage when the battery charging rate becomes more than a threshold value is not only installed in smart phones, but also widely installed in various electronic devices.

[0083] like Figure 6 As shown in the flowchart FG of FIG. 1 , the main body control unit 35 monitors whether the charging rate of the second device battery 31 is 80% or more (step SG1). When the charging rate is detected to be 80% or more (step SG1: yes), the main body control unit 35 communicates with the second device control unit 32 and requests to send a "request to reduce the supplied power" to the control unit 20 of the power supply device 1 (step SG2). In this example, the request is used to request that the power-related value of the supplied power be reduced from 9V, 3A to 5V, 3A.

[0084] As described above, the second device 3 (one device) has a function of receiving power supply to charge the second device battery 31 (battery), and a function of transmitting a request according to the state of the second device battery 31 .

[0085] As shown in flowchart FF, the second device control unit 32 transmits a request in response to the request of the main body control unit 35 (step SF1).

[0086] As shown in the flowchart FD, the control unit 20 of the power supply device 1 receives the request (step SD1). Next, the control unit 20 performs a reallocation process based on the received request (step SD2). The reallocation process is a process of redetermining the distribution of power supplied to the first device 2 and the second device 3. In the reallocation process, the control unit 20 redetermines the distribution of power according to the following conditions.

[0087] <Condition R1′> Within the range where the total power supply value does not exceed the power supply upper limit value, the reduced power for the second device 3 is distributed to the first device 2. Furthermore, the total power supply value after distribution is made as close to the power supply upper limit value as possible.

[0088] <Condition R2'> The allocation to the first device 2 is set as close as possible to the desired power-related value of the first device 2 (in this example, 15V, 3A, i.e., 45W). The voltage of the allocated power is set not to exceed the voltage involved in the desired power-related value. Furthermore, the allocation to the second device 3 is set as close as possible to the "power-related value after reflecting the power reduction based on the request" (in this example, 5V, 3A, i.e., 15W). The voltage of the allocated power is set not to exceed the voltage involved in the "power-related value after reflecting the power reduction based on the request".

[0089] Hereinafter, “the value related to power after the power reduction due to the request is reflected” is referred to as “the value related to requested power”.

[0090] In the case of this example, for example, the control unit 20 Figure 2 As shown in (C), the power-related value of the power supplied to the second device 3 is determined to be 5V, 3A, i.e., 15W, according to the request, and the power-related value of the power supplied to the first device 2 is determined to be 15V, 3A, i.e., 45W. By determining in this way, conditions R1' and R2' are satisfied. That is, with respect to condition R1', on the basis of allocating the reduced power for the second device 3 to the first device 2, the total power supply value (45W+15W=60W) is less than the upper limit value of the power supply (60W) and is as close to the upper limit value of the power supply (60W) as possible. In addition, with respect to condition R2', the allocation (15V, 3A) of the first device 2 and the allocation (5V, 3A) of the second device 3 are each as close as possible to the desired power-related value (15V, 3A) of the first device 2 and the requested power-related value (5V, 3A) of the second device 3.

[0091] Figure 7 (B) is a diagram showing the relationship between the upper limit of the supplied power and the distribution of the power in this example. Figure 7 As shown in (B), in this situation, the total power supply value is equal to the upper limit of the power supply, and efficient power supply is achieved. Figure 5 In addition, by redetermining the distribution of electric power in response to the request for reducing electric power and distributing the reduced electric power to the first device 2, efficient electric power supply is achieved.

[0092] In this example, in the allocation determination process, the control unit 20 Figure 2 As shown in (C), the power-related value of the power supplied to the first device 2 (i.e., the determined power-related value regarding the first device 2) is determined to be 15V, 3A, and the power-related value of the power supplied to the second device 3 (i.e., the determined power-related value regarding the second device 3) is determined to be 5V, 3A.

[0093] As shown in the flowchart FD, after the reallocation process of step SD2, the control unit 20 notifies the first device control unit 27 of the determined power-related value determined for the first device 2, and notifies the second device control unit 32 of the determined power-related value determined for the second device 3 (step SD3). Next, the control unit 20 starts supplying power to the first device 2 and the second device 3 in accordance with the allocation determined in the reallocation process (step SD4). Specifically, the control unit 20 controls the power supply unit 21 to supply the first device 2 with power corresponding to the determined power-related value related to the first device 2, and to supply the second device 3 with power corresponding to the determined power-related value related to the second device 3.

[0094] As shown in flowchart FE, in response to the notification in step SD3 , first device control unit 27 controls first device charging unit 29 to start charging first device battery 26 based on the power supplied from power supply device 1 .

[0095] As shown in flowchart FF, in response to the notification in step SD3 , the second device control unit 32 controls the second device charging unit 34 to start charging the second device battery 31 based on the power supplied from the power supply device 1 .

[0096] As described above, the control unit 20 of the power supply device 1 involved in the present embodiment, after starting to supply power to each of the multiple connected devices DV according to the distribution based on negotiation, when receiving a request to reduce the supplied power from a device DV, reflects the reduction in power requested in the request and redetermines the distribution of power supplied to the multiple connected devices DV.

[0097] According to this configuration, after power supply starts according to the allocation based on negotiation, when a request for reducing the power supply is issued from one of the multiple connected devices DV, the allocation of power supplied to the multiple connected devices DV is re-determined by reflecting the reduction of power requested in the request. Therefore, it is possible to determine a new power allocation without waiting for the next negotiation, and power can be supplied efficiently. That is, according to the present invention, with respect to a power supply device that can supply power to multiple devices DV and can communicate with each device DV, efficient power supply to multiple connected devices DV is achieved.

[0098] The above describes one embodiment of the present invention, which is only an example of a specific implementation of the present invention, and should not be interpreted as limiting the scope of the technology of the present invention. That is, the present invention can be implemented in various forms without departing from its purpose or its main features.

[0099] In the above-mentioned embodiment, the power supply device 1 is mounted on the vehicle. However, the power supply device 1 is not necessarily mounted on the vehicle. In addition, when AC power such as commercial power is supplied to the power supply device 1, the power supply unit 21 is configured to include an AC / DC converter to appropriately perform AC / DC conversion.

[0100] In addition, the function blocks shown in the above-mentioned embodiments can be implemented by any hardware or the cooperation of any hardware and any software. That is, these function blocks are not limited to specific hardware. For example, a certain function block can be set to the following structure when it is composed of hardware and software. That is, the function block is composed of a CPU, RAM and ROM of a computer. In addition, the function block is executed by the CPU reading and executing the program stored in the ROM or other recording medium to the RAM.

[0101] The power supply device 1 described above includes connectors (power supply device first connector 8 and power supply device second connector 9). However, the power supply device may be a type of device that is not provided with a connector and is integrated with a cable that complies with the standard.

[0102] In the above-mentioned embodiment, the control unit 20 redetermines the distribution of power based on the request sent by the second device 3 with the charging rate becoming 80% or more as a trigger. In this regard, the type of request that becomes the trigger for the control unit of the power supply device to redetermine the distribution of power is not limited to the type illustrated in this embodiment. As an example, in USB PD PPS (Programmable Power Supply), a request to change power (of course including reducing power) can be sent from the device to the power supply device, and this request can also be used as a trigger.

[0103] In addition, for example, the processing performed by the control unit 20 alone in the above description may also be configured so that the control unit 20 and an external device cooperate to perform various processing. As an example, the control unit 20 may cooperate with a processor of a device equipped with the power supply device 1 to perform processing, or may cooperate with an external device that can communicate via a network to perform processing.

[0104] In addition, the processing units of the flowcharts of the above-mentioned embodiments are units divided according to the main processing contents in order to make the processing easier to understand. The present invention is not limited by the method or name of the division of the processing units. The processing of each device can also be divided into more processing units according to the processing contents. In addition, it is also possible to divide in a way that one processing unit contains more processing. In addition, as long as the same processing can be performed, the processing order of the above-mentioned flowchart is not limited to the example shown in the figure.

[0105] In addition, for example, the provision of a program executed by a computer of the power supply device 1 can be included in the embodiment. In addition, the provision of a recording medium having the program recorded in a computer-readable manner can be included in the embodiment. As the above-mentioned recording medium, a magnetic recording medium, an optical recording medium or a semiconductor storage device can be used. Specifically, portable or fixed recording media such as a floppy disk, an HDD (Hard Disk Drive), a CD-ROM (Compact Disc Read Only Memory), a DVD (Digital Versatile Disc), a Blu-ray (registered trademark) disk, an optical magnetic disk, a flash memory, and a card-type recording medium can be cited.

Claims

1. A power supply device, characterized in that: have: a power supply unit capable of supplying power to a plurality of connected devices; and a control unit having: a function of controlling the power supplied by the power supply unit; and a function of communicating with the connected device; and a function of communicating and negotiating with the devices before starting to supply power to the devices when power is supplied to the plurality of devices, and determining the distribution of power to be supplied to each of the devices within a range where the total power supplied does not exceed an upper limit value, After power starts to be supplied to each of the multiple connected devices according to the distribution based on the negotiation, when a request is received from one device to reduce the power supplied to the one device, the control unit reflects the reduction in power requested in the request and redetermines the distribution of power supplied to the multiple connected devices.

2. The power supply device according to claim 1, characterized in that: The control unit distributes the power reduced for the one device to the devices other than the one device within a range in which the total of the supplied power does not exceed the upper limit value.

3. The power supply device according to claim 1, characterized in that: The one device is a device having a function of receiving power supply and charging a battery, and a function of transmitting the request according to the state of the battery.

4. The power supply device according to any one of claims 1 to 3, characterized in that: The power supply device is mounted on a vehicle.

5. A power supply system, comprising a power supply device and equipment, characterized in that: The power supply device comprises: a power supply unit capable of supplying power to the plurality of connected devices; and a control unit having: a function of controlling the power supplied by the power supply unit; and a function of communicating with the connected device; and a function of communicating and negotiating with the devices before starting to supply power to the devices when power is supplied to the plurality of devices, and determining the distribution of power to be supplied to each of the devices within a range where the total power supplied does not exceed an upper limit value, After power starts to be supplied to each of the multiple connected devices according to the distribution based on the negotiation, when a request is received from one device to reduce the power supplied to the one device, the control unit of the power supply device reflects the reduction in power requested in the request and redetermines the distribution of power supplied to the multiple connected devices.

6. A control method, performed by a power supply device having a power supply unit capable of supplying power to a plurality of connected devices, characterized in that: The steps include: When power is supplied to a plurality of the devices, the control unit of the power supply device communicates and negotiates with the devices before starting to supply power to the devices, and determines the distribution of power supplied to each of the devices within a range where the total power supplied does not exceed an upper limit value; as well as After power starts to be supplied to each of the multiple connected devices according to the distribution based on the negotiation, when a request is received from one device to reduce the power supplied to the one device, the control unit of the power supply device reflects the reduction in power requested in the request and redetermines the distribution of power supplied to the multiple connected devices.

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