Power supply device

Abstract

A power supply device installed on a vehicle is provided. The power supply device includes: a battery; a power converter connected between the battery and an auxiliary device; a first capacitor; a first relay connected between the first capacitor and a line connecting the power converter and the auxiliary device; a second capacitor; a second relay connected between the second capacitor and a line connecting the power converter and the auxiliary device; and a controller configured to control the first and second relays, wherein when the vehicle's power switch is turned on, the controller turns on the first relay and turns off the second relay, and when the vehicle's power switch is turned off, the controller turns off the first relay and turns on the second relay.

Description

Technical Field

[0001] This invention relates to a power supply device. Background Technology

[0002] In power supply units installed in hybrid or electric vehicles, a DC / DC converter is positioned between a high-voltage system and a low-voltage system. The high-voltage system contains a high-voltage battery that supplies power for propulsion, while the low-voltage system contains auxiliary devices that operate at low voltage. In such a power supply unit, the DC / DC converter steps down the power output from the high-voltage battery, enabling power to be supplied from the high-voltage battery to the auxiliary devices.

[0003] In addition to high-voltage batteries, such power supply devices also include those with low-voltage batteries integrated into the low-voltage system (e.g., JP2019-161839A). Although low-voltage systems typically consume small currents, there may be loads that momentarily consume large currents (e.g., power steering). Low-voltage batteries can handle power fluctuations caused by the presence of such loads, such as fluctuations in the amount of power supplied to each load. Low-voltage batteries can also provide dark current when stationary. However, installing such low-voltage batteries in automobiles is costly and increases vehicle weight.

[0004] Therefore, as Figure 8 As shown, a power supply device is provided that incorporates a capacitor instead of a low-voltage battery. This power supply device continuously stores charge in the capacitor and uses the stored charge to handle power fluctuations and dark currents.

[0005] Patent Document 1: JP2019-161839A Summary of the Invention

[0006] However, as charge is continuously stored in the capacitor, the internal resistance of the capacitor decreases, which reduces the lifespan of the capacitor.

[0007] Therefore, the purpose of this invention is to extend the life of a capacitor that handles power fluctuations and dark current.

[0008] To address the aforementioned problems, the power supply device of the present invention is a power supply device installed in a vehicle, comprising: a battery; a power converter connected between the battery and an auxiliary device; a first capacitor; a first relay connected between the line connecting the power converter and the auxiliary device and the first capacitor; a second capacitor; a second relay connected between the line connecting the power converter and the auxiliary device and the second capacitor; and a controller configured to control the first and second relays, wherein when the vehicle's power switch is turned on, the controller turns on the first relay and turns off the second relay, and when the vehicle's power switch is turned off, the controller turns off the first relay and turns on the second relay.

[0009] The controller can use the charge stored in the first capacitor to charge the second capacitor.

[0010] The controller can activate the second relay when the vehicle's power switch is turned off, and the controller can deactivate the first relay after a first duration has elapsed following the vehicle's power switch being turned off.

[0011] The controller can charge the first capacitor with the charge stored in the second capacitor.

[0012] The controller can activate the first relay when the vehicle's power switch is turned on, and the controller can deactivate the second relay after a second duration has elapsed after the vehicle's power switch is turned on.

[0013] According to the present invention, the lifespan of capacitors that handle power fluctuations and dark currents can be extended. Attached Figure Description

[0014] Figure 1 A power supply device 100 according to an embodiment of the present invention is shown;

[0015] Figure 2 The flow of electricity in the power supply device 100 is illustrated.

[0016] Figure 3 The flow of electricity in the power supply device 100 is illustrated.

[0017] Figure 4 The flow of electricity in the power supply device 100 is illustrated.

[0018] Figure 5 This is a flowchart of an exemplary processing operation in a power supply device 100 according to an embodiment of the present invention;

[0019] Figure 6 The flow of electricity in the power supply device 100 is illustrated.

[0020] Figure 7This is a flowchart of an exemplary processing operation in a power supply device 100 according to an embodiment of the present invention; and

[0021] Figure 8 An exemplary known power supply device is shown.

[0022] Reference Symbol List

[0023] 100 Power supply unit

[0024] 110 battery

[0025] 120 Power Converter

[0026] 130 First Capacitor

[0027] 140 First Relay

[0028] 150 Second capacitor

[0029] 160 Second Relay

[0030] 170 Controller

[0031] ACC auxiliary device Detailed Implementation

[0032] <Power Supply Unit 100>

[0033] Figure 1 A power supply device 100 according to an embodiment of the present invention is shown. The power supply device 100 includes a battery 110, a power converter 120, a first capacitor 130, a first relay 140, a second capacitor 150, a second relay 160, and a controller 170. The power supply device 100 is installed in a vehicle such as an automobile.

[0034] Battery 110 provides power. Battery 110 is, for example, a high-voltage battery that provides power for vehicle operation.

[0035] A power converter 120 is connected between the battery 110 and the auxiliary device ACC. The power converter 120 is, for example, a DC / DC converter, and the voltage of the power output from the battery 110 is converted by the power converter 120 and supplied to the auxiliary device ACC. Although in Figure 1 The diagram shows a single auxiliary device ACC, however, multiple auxiliary devices ACC can be configured.

[0036] The first capacitor 130 is connected via a first relay 140 to the line connecting the power converter 120 to the auxiliary device ACC. Therefore, in this embodiment, when the first relay 140 is turned on, as... Figure 2As shown, the first capacitor 130 can be charged using the power supplied from the battery 110 via the power converter 120, and the power charged into the first capacitor 130 can be supplied to the auxiliary device ACC.

[0037] The second capacitor 150 is connected via the second relay 160 to the line connecting the power converter 120 to the auxiliary device ACC. Therefore, in this embodiment, when the second relay 160 is turned on, as... Figure 3 As shown, the second capacitor 150 can be charged using the power supplied from the battery 110 via the power converter 120, and the power charged into the second capacitor 150 can be supplied to the auxiliary device ACC.

[0038] The controller 170 controls the first relay 140 and the second relay 160.

[0039] When a power switch of the vehicle, such as an auxiliary switch or ignition switch, is turned on, the controller 170 turns on the first relay 140 and turns off the second relay 160.

[0040] Therefore, in this embodiment, when the vehicle's power switch is turned on, for example, when the vehicle is in use, the first capacitor 130 can be charged using the power supplied from the battery 110 via the power converter 120, and the power charged into the first capacitor 130 can be supplied to the auxiliary device ACC. That is, in this embodiment, the first capacitor 130 can suppress power fluctuations that occur when the vehicle is in use.

[0041] On the other hand, in this embodiment, when the vehicle's power switch is turned on, the second capacitor 150 is disconnected from the power converter 120 and the auxiliary device ACC, so the second capacitor 150 does not need to store charge. Therefore, when the vehicle's power switch is turned on, the controller 170 can discharge the second capacitor 150, causing the second capacitor 150 to enter a state without stored charge. Preferably, for example, the positive electrode side (negative electrode side) of the second capacitor 150 can be connected to the same potential as the negative electrode side (positive electrode side) of the second capacitor 150 via a resistor and a switch. With this arrangement, the controller 170 turns on the switch while the second relay 160 remains open, causing the second capacitor 150 to discharge. Therefore, the second capacitor 150 is able to enter a state without stored charge.

[0042] When the vehicle's power switch is turned off, the controller 170 disconnects the first relay 140 and connects the second relay 160.

[0043] Therefore, in this embodiment, when the vehicle's power switch is off, for example, when the vehicle is parked, the second capacitor 150 can be charged using the power supplied from the battery 110 via the power converter 120, and the power charged in the second capacitor 150 can be supplied to the auxiliary device ACC. That is, in this embodiment, the second capacitor 150 can provide dark current when parked. Preferably, when the vehicle's power switch is off, the controller 170, for example, intermittently operates the power converter 120, causing the second capacitor 150 to be periodically charged by the battery 110.

[0044] On the other hand, in this embodiment, when the vehicle's power switch is off, the first capacitor 130 is disconnected from the power converter 120 and the auxiliary device ACC, so the first capacitor 130 does not need to store charge. Therefore, when the vehicle's power switch is off, the controller 170 can discharge the first capacitor 130, causing the first capacitor 130 to enter a state without stored charge. Preferably, for example, the positive electrode side (negative electrode side) of the first capacitor 130 can be connected to the same potential as the negative electrode side (positive electrode side) of the first capacitor 130 via a resistor and a switch. With this arrangement, the controller 170 turns on the switch while the first relay 140 remains off, causing the first capacitor 130 to discharge. Therefore, the first capacitor 130 can enter a state without stored charge.

[0045] As described above, the power supply device 100 according to this embodiment includes two capacitors: a first capacitor 130, which suppresses power fluctuations; and a second capacitor 150, which provides dark current. In this embodiment, when the vehicle's power switch is turned on, the first capacitor 130 does not need to store charge, and when the vehicle's power switch is turned off, the second capacitor 150 does not need to store charge. Therefore, in this embodiment, when the vehicle's power switch is turned off, the first capacitor 130 can enter a state without stored charge, and when the vehicle's power switch is turned on, the second capacitor 150 can enter a state without stored charge. Therefore, compared to the case where the first capacitor 130 and the second capacitor 150 continuously store charge, the lifespan of the first capacitor 130 and the second capacitor 150 can be extended.

[0046] Furthermore, in this embodiment, the first capacitor 130 can be made to a size suitable for handling power fluctuations, and the second capacitor 150 can be made to a size suitable for handling dark current. Therefore, an appropriate amount of charge can be stored in the first capacitor 130 and the second capacitor 150.

[0047] <Charging using the charge stored in the capacitor>

[0048] To reduce the amount of charge stored in the first capacitor 130 to zero, the controller 170 can use the charge stored in the first capacitor 130 to charge the battery 110 or the second capacitor 150. This arrangement allows for efficient use of the charge stored in the first capacitor 130 so that the amount of charge stored in the first capacitor 130 is zero.

[0049] Preferably, for example, the controller 170 operates the power converter 120 until the first relay 140 is disconnected after the vehicle's power switch is switched from on to off, causing power to flow from the first capacitor 130 to the battery 110. This arrangement allows the charge stored in the first capacitor 130 to be used to charge the battery 110.

[0050] Preferably, for example, when the vehicle's power switch is switched from on to off, the controller 170 activates the second relay 160, and then deactivates the first relay 140 after a first duration has elapsed following the vehicle's power switch being off. Given that both the first relay 140 and the second relay 160 remain on, as... Figure 4 As shown, this arrangement allows the charge stored in the first capacitor 130 to be used to charge the second capacitor 150 during the first duration. Furthermore, preferably, the controller 170 operates the power converter 120 during the first duration, causing power to flow from the first capacitor 130 to the battery 110. This arrangement allows the charge stored in the first capacitor 130 to be used to charge both the battery 110 and the second capacitor 150.

[0051] Figure 5 This is a flowchart of the processing operation performed in the power supply device 100 according to this embodiment when the vehicle's power switch is switched from on to off. The second relay 160 is turned on (step S501), and after a first duration has elapsed after the vehicle's power switch is turned off (Yes in step S502), the first relay 140 is turned off (step S503).

[0052] Furthermore, in order to reduce the amount of charge stored in the second capacitor 150 to zero, the controller 170 can use the charge stored in the second capacitor 150 to charge the battery 110 or the first capacitor 130. This arrangement enables efficient use of the charge stored in the second capacitor 150 so that the amount of charge stored in the second capacitor 150 is zero.

[0053] Preferably, for example, the controller 170 operates the power converter 120 until the second relay 160 is disconnected after the vehicle's power switch is switched from off to on, causing power to flow from the second capacitor 150 to the battery 110. This arrangement allows the charge stored in the second capacitor 150 to be used to charge the battery 110.

[0054] Preferably, for example, when the vehicle's power switch switches from off to on, the controller 170 activates the first relay 140, and then deactivates the second relay 160 after a second duration has elapsed since the vehicle's power switch was on. This arrangement allows the charge stored in the second capacitor 150 to be used to charge the first capacitor 130 during the second duration, because both the first relay 140 and the second relay 160 remain on. Figure 6 As shown. Furthermore, the charge stored in the second capacitor 150 can be used to start the vehicle. Additionally, preferably, the controller 170 operates the power converter 120 during a second duration, causing power to flow from the second capacitor 150 to the battery 110. This arrangement allows the charge stored in the second capacitor 150 to be used to charge both the battery 110 and the first capacitor 130.

[0055] Figure 7 This is a flowchart of the processing operation performed in the power supply device 100 according to this embodiment when the vehicle's power switch is switched from off to on. The first relay 140 is turned on (step S701), and after a second duration has elapsed after the vehicle's power switch is turned on (Yes in step S702), the second relay 160 is turned off (step S703).

[0056] <Capacitor Arrangement>

[0057] Preferably, for example, the first capacitor 130 is disposed at the front of the vehicle. Short-term loads are typically disposed at the front of the vehicle. Therefore, the arrangement of the first capacitor 130 at the front of the vehicle shortens the wiring distance between the first capacitor 130 and the short-term load, making the power supply from the first capacitor 130 to the short-term load stable.

[0058] Preferably, the second capacitor 150 is disposed in the center of the vehicle interior. Auxiliary devices that consume dark current are typically located inside the vehicle. Therefore, the central placement of the second capacitor 150 within the vehicle interior shortens the wiring distance between the second capacitor 150 and the auxiliary devices that consume dark current, ensuring a stable power supply from the second capacitor 150 to such auxiliary devices.

[0059] The invention has been described above with reference to preferred embodiments. Specific examples have been given herein to illustrate the invention. However, various modifications and changes may be made to the specific examples without departing from the spirit and scope of the invention as described in the claims.

Claims

1. A power supply device installed on a vehicle, the power supply device comprising: Battery; A power converter that is connected between the battery and the auxiliary device; First capacitor; A first relay is connected between the line connecting the power converter and the auxiliary device and the first capacitor; Second capacitor; A second relay is connected between the line connecting the power converter and the auxiliary device and the second capacitor; as well as A controller configured to control the first relay and the second relay. The controller is configured as follows: When the vehicle's power switch is turned on, the controller activates the first relay and deactivates the second relay, thereby disconnecting the second capacitor from the power converter and the auxiliary device; and When the power switch of the vehicle is turned off, the controller disconnects the first relay and turns on the second relay, thereby separating the first capacitor from the power converter and the auxiliary device.

2. The power supply device according to claim 1, wherein, The controller uses the charge stored in the first capacitor to charge the second capacitor.

3. The power supply device according to claim 2, wherein, When the power switch of the vehicle is turned off, the controller turns on the second relay, and when a first duration has elapsed after the power switch of the vehicle is turned off, the controller turns off the first relay.

4. The power supply device according to any one of claims 1 to 3, wherein, The controller charges the first capacitor using the charge stored in the second capacitor.

5. The power supply device according to claim 4, wherein, When the power switch of the vehicle is turned on, the controller turns on the first relay, and when a second duration has elapsed after the power switch of the vehicle is turned on, the controller turns off the second relay.

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