Power system

Abstract

The invention provides a power system. A power system configured to supply power to a load system requiring a redundant power supply configuration includes: a main power supply configured to supply power to the load system via a first path; a backup power supply for backing up the power supply from the main power supply; and the switching unit is connected with the main power supply and the standby power supply. When the output voltage of the main power supply is higher than the output voltage of the backup power supply, the switching means supplies power from the main power supply to the load system via a second path different from the first path.

Description

Technical Field

[0001] The present disclosure relates to a power system that supplies power to a load system that requires a redundant power supply structure mounted on a vehicle or the like. Background Art

[0002] In Japanese Unexamined Patent Application Publication No. 2022-093883, a vehicle-mounted backup control device is disclosed. The backup control device controls so as not to consume the power of the backup power supply when the main power supply is normal, and controls so as to quickly supply the power of the backup power supply to the load when the main power supply is abnormal.

[0003] In the backup control device described in the above-mentioned Japanese Unexamined Patent Application Publication No. 2022-093883, during the period when the backup power supply is standby in a state where backup operation can be performed at any time, the backup power supply is controlled in a charged state. Therefore, when a failure occurs in the main power supply and the backup operation is actually performed, it takes time until the backup power supply is switched from the charge control state to the discharge control state, and it may be difficult to supply the required power from the backup power supply to the load within the required time. Summary of the Invention

[0004] The present disclosure provides a power system that can supply the required power from a backup power supply to a load within the required time when a failure occurs in the main power supply and backup operation is required.

[0005] One aspect of the technology of the present disclosure is a power system configured to supply power to a load system that requires a redundant power supply structure, wherein the power system includes: a main power supply configured to supply power to the load system via a first path; a backup power supply for backing up the power supply by the main power supply; and a switching unit connected to the main power supply and the backup power supply. The switching unit is configured to: when the output voltage of the main power supply is higher than the output voltage of the backup power supply, supply power from the main power supply to the load system via a second path different from the first path. The switching unit is configured to: when the output voltage of the main power supply is lower than the output voltage of the backup power supply, supply power from the backup power supply to the load system via the second path.

[0006] According to the power system of the above aspect of the present disclosure, when a failure occurs in the main power supply and the output voltage decreases (or disappears), the switching unit quickly supplies the power of the backup power supply with a higher output voltage to the load system. Thus, when the main power supply fails, the required power can be supplied from the backup power supply to the load within the required time. Brief Description of the Drawings

[0007] Hereinafter, the features, advantages, and technical and industrial significance of the embodiments of the present invention will be described with reference to the accompanying drawings. The same reference numerals denote the same elements, where

[0008] Figure 1 is a schematic structural diagram of a power system and a load system according to one embodiment of the present disclosure.

[0009] Figure 2 is a diagram showing the circuit state when the power system is in a standby state.

[0010] Figure 3 is a diagram showing the circuit state when the power system is in a standby operating state.

[0011] Figure 4 is a diagram showing the circuit state when the power system is in a standby capacity ensuring state. Detailed Embodiment

[0012] In the power system of the embodiment of the present disclosure, a path directly connected to the main power supply and a switch that is separated from the path for power supply from the standby power supply are provided. In addition, a switching unit is provided in the power system. When the main power supply is normal, the switching unit does not consume the power of the standby power supply in a discharged state, and when the main power supply fails, the standby power supply consumes the above power. Thus, standby power supply using the standby power supply when the main power supply fails can be appropriately performed. Hereinafter, one embodiment of the present disclosure will be described in detail with reference to the accompanying drawings.

[0013] <Embodiment>

[0014] [Structure]

[0015] Figure 1 is a block diagram showing a schematic structure of a power system 100 according to one embodiment of the present disclosure and a load system 200 that receives power supply from the power system 100. The power system 100 and the load system 200 are mounted on a vehicle or the like.

[0016] The load system 200 is a system that operates using the power supplied from the power system 100 and is a system that needs to perform standby operation using standby power in an emergency. The load system 200 includes a primary system device 210 and a secondary system device 220 having the same functions and performance, and is redundantly structured by making the power supply paths for the respective devices different. As the load system 200 mounted on a vehicle, an electric shift (SBW) system, a braking system, a steering system, etc. can be exemplified. In addition, as the primary system device 210 and the secondary system device 220, an actuator (ACT), an electronic control unit (ECU), etc. required for system operation can be exemplified. Further, in Figure 1The number of load systems 200 shown is one, but the load systems 200 receiving power supply from the power system 100 are not limited to one.

[0017] The power system 100 is a system with a redundant power supply structure for supplying power to the load system 200. The power system 100 includes a main power supply 110, a backup power supply 120, a switching unit 130, a first switch 141, and a second switch 142.

[0018] The main power supply 110 is a power supply that supplies the power required for the operation of the load system 200. In the power system 100, as a path capable of supplying power to the load system 200, there are constituted a "first path 151" connected to the primary system device 210 of the load system 200 via the first switch 141, and a "second path 152" connected to the secondary system device 220 of the load system 200 via the switching unit 130 (third switch 131). In addition, the main power supply 110 is also a power supply capable of supplying power for charging the backup power supply 120 as needed. The main power supply 110 can be a power supply that always supplies +B voltage power in the vehicle regardless of the ignition state.

[0019] The first switch 141 is a structure for switching the on / off state of the power between the main power supply 110 and the primary system device 210, with one end connected to the main power supply 110 and the other end connected to the primary system device 210 of the load system 200. The first switch 141 has the following function: it conducts power during normal operation and cuts off power when the main power supply 110 fails due to grounding or the like, thereby disconnecting the main power supply 110 from the load system 200 so that the impact of the failure does not spread to the load system 200.

[0020] The second switch 142 is a structure for switching the on / off state of the power between the backup power supply 120 and the primary system device 210, with one end connected to the primary system device 210 of the load system 200 and the other end connected to the backup power supply 120 (DCDC converter 122). The second switch 142 has the following function: it cuts off power during normal operation and conducts power when directly connected to the main power supply 110 or when the main power supply 110 fails and cannot supply power to the primary system device 210 of the load system 200, thereby connecting the first path 151 to the backup power supply 120.

[0021] For the above-described first switch 141 and second switch 142, a relay unit formed by connecting two field effect transistors (FETs: Field Effect Transistors) in series such that the rectifying directions of the body diodes are opposite can be used, for example. In addition, the switching control of the first switch 141 and the second switch 142 is performed based on an instruction from a control device (not shown) such as a microcomputer.

[0022] The backup power supply 120 is a power supply for backup-supplying power to the load system 200 in place of the main power supply 110 when an abnormality occurs in the power supply from the main power supply 110 to the load system 200 due to a power failure or the like. The backup power supply 120 includes a power storage unit 121 and a DCDC converter 122.

[0023] The power storage unit 121 is composed of a power storage element such as a capacitor, for example, and functions as a redundant power supply for the main power supply 110. The power storage unit 121 is connected to the DCDC converter 122 so as to be capable of charging and discharging. In addition, the power storage unit 121 may be composed of a secondary battery (such as a lithium ion battery) configured to be capable of charging and discharging.

[0024] The DCDC converter 122 is a power converter for converting the input power into power of a specified voltage and outputting it. The DCDC converter 122 can charge the power storage unit 121 with the power supplied from the main power supply 110 via the first switch 141 and the second switch 142 (charging control state). In addition, the DCDC converter 122 can supply the power (backup power) stored in the power storage unit 121 to the primary system device 210 of the load system 200 via the second switch 142, or supply it to the secondary system device 220 of the load system 200 via the switching unit 130 (diode 132) (discharge control state). For this DCDC converter 122, a step-up / step-down type bidirectional DCDC converter can be used, for example. In addition, the control of the DCDC converter 122 is performed based on an instruction from a control device (not shown) such as a microcomputer.

[0025] The switching unit 130 is configured to connect the main power supply 110 and the backup power supply 120 as input sources and connect the load system 200 as an output destination. The switching unit 130 supplies the power of either the main power supply 110 or the backup power supply 120 to the secondary system device 220 of the load system 200 with priority over the power of the other power supply. The supply of power is performed via a second path 152 different from the first path 151. The switching unit 130 includes a third switch 131 and a diode 132.

[0026] The third switch 131 is a structure that is connected at one end to the main power supply 110 and at the other end to the secondary system device 220 of the load system 200, and is used to switch the power conduction / power cut-off state between the main power supply 110 and the secondary system device 220. For this third switch 131, for example, a relay unit formed by connecting two field effect transistors (FETs) in series with the rectification directions of the body diodes opposite to each other can be used. The third switch 131 has the following function: it conducts electricity during normal operation, cuts off in the case of a failure of the main power supply 110 due to grounding or the like, and disconnects the main power supply 110 from the switching unit 130 to prevent the influence of the failure from spreading to the backup power supply 120 and the load system 200. In addition, the switching control of the third switch 131 is performed based on an instruction from a control device (not shown) such as a microcomputer.

[0027] The diode 132 is an element that connects the backup power supply 120 to the anode and the secondary system device 220 of the load system 200 to the cathode, and rectifies from the backup power supply 120 toward the secondary system device 220.

[0028] With the above circuit structure, when the output voltage (+B) of the main power supply 110 is higher than the output voltage (Vb) of the DCDC converter 122 in the backup power supply 120, the switching unit 130 operates in such a way that the power of the main power supply 110 is supplied to the secondary system device 220 of the load system 200. On the other hand, when the output voltage (+B) of the main power supply 110 is lower than the output voltage (Vb) of the DCDC converter 122 in the backup power supply 120, the switching unit 130 operates in such a way that the power of the power storage unit 121 in the backup power supply 120 is supplied to the secondary system device 220 of the load system 200. That is, in the switching unit 130, according to the level of the output voltage of the power supply, the control of switching the power supply for the secondary system device 220 is performed.

[0029] [Control]

[0030] Next, further refer to Figure 2 、 Figure 3 and Figure 4 to describe the control state in the power system 100 according to one embodiment of the present disclosure.

[0031] (1) Standby standby state

[0032] Figure 2 It represents the circuit state when, in a state where no abnormality such as a failure occurs in the main power supply 110 and the power system 100 is normal, functions that require standby control such as remote parking are operating, and thus the power system 100 is in a "standby standby state" where it stands by in a manner capable of standby.

[0033] AsFigure 2 As shown, when the power system 100 is in the standby state, the first switch 141 and the third switch 131 are respectively controlled to be in the on state, and the second switch 142 is controlled to be in the off state. In addition, when the power system 100 is in the standby state, the DCDC converter 122 of the standby power supply 120 makes its output voltage (Vb) a value lower than the output voltage (+B) of the main power supply 110, and is controlled to be in a state capable of discharging from the power storage unit 121 (discharge control state).

[0034] Through these controls, in this standby state, power is supplied from the main power supply 110 to the primary system device 210 of the load system 200 via the first path 151, and power is supplied from the main power supply 110 to the secondary system device 220 of the load system 200 via the second path 152 ( Figure 2 thick line path).

[0035] (2) Standby operation state

[0036] Figure 3 Indicates the circuit state in the "standby operation state" where standby control has worked when an abnormality such as a failure occurs in the main power supply 110 and the power system 100 is no longer normal during the operation of functions that require standby control such as remote parking ( Figure 2 state).

[0037] As Figure 3 shown, when the power system 100 is in the standby operation state, the first switch 141 and the third switch 131 are respectively controlled to be in the off state, and the second switch 142 is controlled to be in the on state. In addition, when the third switch 131 is turned off, the output voltage (Vb) of the standby power supply 120 (DCDC converter 122) is higher than the other end of the third switch 131.

[0038] Through these controls, in this standby operation state, power is supplied from the standby power supply 120 to the primary system device 210 of the load system 200 via the first path 151, and power is supplied from the standby power supply 120 to the secondary system device 220 of the load system 200 via the second path 152 ( Figure 3 thick line path). Since the standby power supply 120 starts the standby process of the main power supply 110 in the discharge control state, there is no need for the time to switch from the charge control state to the discharge control state, and power can be immediately supplied to the load system 200 via the first path 151 and the second path 152.

[0039] (3) Standby capacity ensuring state

[0040] Figure 4Indicates the circuit state in the "standby capacity ensuring state" where, when the charging capacity of the standby power supply 120 is less than the standby capacity, the power of the main power supply 110 is used to charge the power storage unit 121 of the standby power supply 120.

[0041] As Figure 4 shown, when the power system 100 is in the standby capacity ensuring state, the first switch 141, the second switch 142, and the third switch 131 are all controlled to be in the conducting state.

[0042] Through these controls, in this standby capacity ensuring state, power is supplied from the main power supply 110 to the primary system device 210 of the load system 200 via the first path 151, and power is supplied from the main power supply 110 to the secondary system device 220 of the load system 200 via the second path 152 ( Figure 4 thick line path). Also, in the standby capacity ensuring state, power is supplied from the main power supply 110 to the standby power supply 120 to charge the power storage unit 121 (main power supply direct connection).

[0043] <Function and Effect>

[0044] As described above, in the power system 100 according to one embodiment of the present disclosure, the first path 151 and the second path 152 are provided as paths for supplying power from the main power supply 110 to the load system 200. In the second path 152, the switching unit 130 that outputs the power of the power supply with the higher output voltage among the main power supply 110 and the standby power supply 120 is inserted. In addition, the following structure is adopted: between the first path 151 and the second path 152, the second switch 142 capable of switching the two paths to the conducting / cutting-off state is provided, enabling direct connection of the main power supply to the standby power supply 120. Moreover, in this structure, the power system 100 according to the present embodiment waits for the standby power to be supplied to the load system 200 in a state where the standby power supply 120 is controlled to be able to discharge from the power storage unit 121 (discharge control state).

[0045] Thereby, when the main power supply 110 is normal, power consumption from the standby power supply 120 can be suppressed (power consumption of standby power is reduced when the main power supply is normal). In addition, when a failure occurs in the main power supply 110 and the output voltage decreases or disappears, the switching unit 130 switches the power supply to the load system 200 from the main power supply 110 to the standby power supply 120, and power can be quickly supplied from the standby power supply 120 in the discharge control state to the load system 200 (responsiveness of standby power supply is ensured when the main power supply fails).

[0046] As described above, one embodiment of the present disclosure technology has been described. However, the present disclosure can be understood as a power system, a control method executed by a power system including a processor and a memory, a control program for executing the control method, a computer-readable non-transitory storage medium storing the control program, and a vehicle equipped with the power system, etc.

[0047] The power system of the present disclosure can be used for vehicles and the like that equip a load system with a power supply structure that requires redundancy.

Claims

1. A power system configured to supply power to a load system that requires a redundant power supply structure. The power system is characterized by comprising: A main power supply configured to supply power to the load system via a first path; A backup power supply for backing up the power supply performed by the main power supply; and A switching unit connected to the main power supply and the backup power supply, wherein The switching unit is configured to: when the output voltage of the main power supply is higher than the output voltage of the backup power supply, supply power from the main power supply to the load system via a second path different from the first path, and The switching unit is configured to: when the output voltage of the main power supply is lower than the output voltage of the backup power supply, supply power from the backup power supply to the load system via the second path.

2. The power system according to claim 1, characterized in that It further comprises a switch configured to control the on / off state of the power between the first path and the backup power supply, wherein The switch is configured to: when charging the backup power supply with the power of the main power supply and when the main power supply fails, control the first path and the backup power supply to be in a conductive state.

3. The power system according to claim 1 or 2, characterized in that The backup power supply comprises: A power storage unit configured to store power; and A DCDC converter configured to control the charge / discharge state of the power storage unit, The DCDC converter is configured to: when power capable of being backed up is stored in the power storage unit, control the power storage unit to be in a discharge state and output power to the switching unit.

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