VEHICLE'S OWN CONTROL DEVICE

Abstract

A voltage conversion unit (30) performs a first conversion operation, in which a voltage applied to a third power path (83) is converted and an output voltage is applied to a fourth power path (84), and a second conversion operation, in which a voltage applied to the fourth power path (84) is converted and an output voltage is applied to the third power path (83). A control unit (16) controls the voltage conversion unit (30). A first circuit element section (21) is capable of allowing a current to flow from the first power path (81) to the third power path (83) and of interrupting a current flow from the third power path (83) to the first power path (81).A second circuit element section (22) is capable of allowing a current to flow from a conductive intermediate path (89) between a first power storage unit (92A) and a second power storage unit (92B) to a second power path (82), and of interrupting a current flow from the second power path (82) to the conductive intermediate path (89).

Description

TECHNICAL AREA

[0001] The present disclosure relates to a vehicle-integrated control unit. TECHNICAL BACKGROUND

[0002] Patent document No. 1 discloses a power supply system. The power supply system according to patent document No. 1 comprises a main battery and a secondary battery and is operated to switch the power supply source for a load from the main battery to the secondary battery when the power supply from the main battery is interrupted. In the power supply system according to patent document No. 1, a switch between the secondary battery and the load includes a body diode, and when the power from the main battery is interrupted, power is supplied to the load via the body diode even though the switch is off, so that the power supply is not interrupted. PREVIOUSLY KNOWN TECHNICAL DOCUMENTS PATENT DOCUMENTS

[0003] Patent Document No. 1: JP 2020 - 182 318 A OVERVIEW OF THE INVENTION TASKS TO BE SOLVED FROM THE INVENTION

[0004] The power supply system according to patent document No. 1 has the risk that, if the output voltage of the secondary battery drops, an adequate voltage cannot be supplied to the load. To solve this problem, it is desirable to use a discharge circuit that can supply an adequate voltage to the load based on power from the secondary battery. However, simply using such a discharge circuit would complicate the design of the device. On the other hand, in a system that can supply power to a load from a secondary battery, if the secondary battery is discharged for any reason, it is necessary to recharge the secondary battery in the event of a fault, and it is therefore desirable to use a charging circuit that can supply an adequate voltage to the secondary battery. However, simply using such a charging circuit would lead to further complications.

[0005] The present disclosure relates to a vehicle-integrated control unit capable of performing a backup operation for supplying power based on a power storage unit. An object of the present invention is to provide a technique that can adapt a charging voltage when charging the power storage unit and a discharging voltage when discharging the power storage unit with a simpler design, and that can discharge the power storage unit via a path that differs from the path on which the voltages are adapted. MEANS OF SOLVING THE TASK

[0006] A vehicle-integrated control device according to the present disclosure is a vehicle-integrated control device for use in a vehicle-integrated system, which is provided with: a power source unit for supplying power; a power storage unit, which is different from the power source unit; a first power path, to which power is supplied from the power source unit; and a second power path, which serves as a path for supplying power supplied from the first power path to a load, wherein the vehicle-integrated control device is configured to control a power supply from the power storage unit, and comprises: a voltage conversion unit provided between the second power path and the power storage unit and configured to perform a first conversion operation in which a voltage applied to a third power path provided on one side of the second power path is converted and an output voltage is applied to a fourth power path provided on one side of the power storage unit, and a second conversion operation in which a voltage applied to the fourth power path is converted and an output voltage is applied to the third power path; a control unit designed to control the voltage conversion unit; and a first circuit element section capable of allowing a current to flow from the first power path to the third power path, and of interrupting a current flow from the third power path to the first power path, wherein the power storage unit comprises a first power storage unit and a second power storage unit, which is located on a side with a lower potential than the first power storage unit and is connected in series with the first power storage unit and The vehicle's own control unit further comprises a second circuit element section capable of allowing a current to flow from a conductive intermediate path between the first power storage unit and the second power storage unit to the second power path, and of interrupting a current flow from the second power path to the conductive intermediate path. EFFECT OF INVENTION

[0007] The technology according to the present disclosure can adjust a charging voltage when charging a power storage unit and a discharging voltage when discharging the power storage unit with a simpler design and can discharge the power storage unit via a path that differs from the path on which the voltages are adjusted. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a circuit diagram that schematically shows an example of a vehicle-specific system that includes a vehicle-specific control unit according to a first embodiment. Fig. Figure 2 is an illustrative diagram that shows an example of an operation in which a power storage unit is charged when a first power path is in a normal state. Fig. Figure 3 is an illustrative diagram that shows an example of an operation in which power is supplied to a second power storage unit when a first power path is in normal operation. Fig. Figure 4 is an illustrative diagram that shows an example of an operation in which power from a power source unit undergoes voltage conversion by a voltage conversion unit and is fed to a second power path. Fig. Figure 5 is an illustrative diagram showing an example of a power supply operation carried out by the vehicle's control unit according to the first embodiment when the first power path has a value not greater than a first threshold and immediately after a fault determination condition has been met. Fig. Figure 6 is an illustrative diagram that shows an example of a power supply operation carried out by the vehicle's control unit according to the first embodiment after a certain time has elapsed since the fault determination condition was met. Fig. Figure 7 is an illustrative diagram showing variations of circuit element sections. FORMS OF EXECUTION OF THE INVENTION

[0008] The following are embodiments of the present disclosure listed and described.

[0009] [1] A vehicle-integrated control device for use in a vehicle-integrated system comprising a power source unit for supplying power; a power storage unit distinct from the power source unit; a first power path to which power is supplied from the power source unit; and a second power path serving as a path for supplying power supplied from the first power path to a load, is configured to control a power supply from the power storage unit and comprises: a voltage conversion unit provided between the second power path and the power storage unit and configured to perform a first conversion operation in which a voltage applied to a third power path provided on one side of the second power path is converted and an output voltage is applied to a fourth power path provided on one side of the power storage unit, and a second conversion operation in which a voltage applied to the fourth power path is converted and an output voltage is applied to the third power path; a control unit designed to control the voltage conversion unit; and a first circuit element section capable of allowing a current to flow from the first power path to the third power path, and of interrupting a current flow from the third power path to the first power path, wherein the power storage unit comprises a first power storage unit and a second power storage unit, which is located on a side with a lower potential than the first power storage unit and is connected in series with the first power storage unit and The vehicle's own control unit further comprises a second circuit element section capable of allowing a current to flow from a conductive intermediate path between the first power storage unit and the second power storage unit to the second power path, and of interrupting a current flow from the second power path to the conductive intermediate path.

[0010] By causing the voltage conversion unit to perform the first conversion operation, whereby the first circuit element section allows current to flow from the first power path to the third power path, the vehicle's control unit can charge the power storage unit and apply a desired voltage to the fourth power path. Likewise, by causing the voltage conversion unit to perform the second conversion operation, the vehicle's control unit can supply power to the second power path and apply a desired voltage to the third power path.In other words, the vehicle's control unit can adjust a charging voltage when charging the power storage unit and a discharge voltage when discharging the power storage unit with a simpler design. In some cases, the first circuit element section can interrupt current flow from the third power path to the first power path. Furthermore, it is possible to discharge the second power storage unit via a path other than the one on which the voltages are adjusted by the voltage conversion unit, since the second circuit element section is provided and allows current to flow from the conductive intermediate path between the first and second power storage units to the second power path.Furthermore, in some cases it is possible to interrupt the current flow from the second power path through the second circuit element section to the second power storage unit, since the second circuit element section can interrupt the current flow from the second power path to the conductive intermediate path. Moreover, according to the configuration in which the second power storage unit is discharged via the second circuit element section, the output voltage is lower than in the configuration in which the power storage unit is discharged directly. Therefore, it is easier to prevent the voltage applied to the load from exceeding the load's nominal voltage.

[0011] [2] The vehicle's own control unit according to [1] further features: a third circuit element section, which is provided between the fourth power path and a fifth power path and to which an output voltage of the power storage unit is applied; and a fourth circuit element section provided in parallel to an arrangement in which the third circuit element section and the first power storage unit are connected in series, wherein the third circuit element section is configured to interrupt a current flow from the fifth power path to the fourth power path via the third circuit element section when the third circuit element section is switched off, and to allow a current to flow from the fifth power path via the third circuit element section to the fourth power path when the third circuit element section is switched on, the fourth circuit element section is configured to interrupt current flow from the fourth power path through the fourth circuit element section to the conductive intermediate path when the fourth circuit element section is switched off, and to allow current flow from the fourth power path through the fourth circuit element section to the conductive intermediate path when the fourth circuit element section is switched on, when the control unit switches on the third circuit element section, switches off the fourth circuit element section and causes the voltage conversion unit to perform the first conversion operation, power is supplied from the voltage conversion unit to the power storage unit and, When the control unit switches off the third circuit element section, switches on the fourth circuit element section and causes the voltage conversion unit to perform the first conversion operation, power is supplied from the voltage conversion unit to the second power storage unit via the fourth circuit element section.

[0012] The vehicle's own control unit can selectively supply power from the voltage conversion unit to the power storage unit or - bypassing the first power storage unit - to the second power storage unit.

[0013] [3] In the vehicle's control unit according to [2], the control unit causes the voltage conversion unit to perform the first conversion operation by switching off the third circuit element section and switching on the fourth circuit element section, thereby allowing a current to flow from the first power path via the first circuit element section to the third power path and a current to flow from the conductive intermediate path via the second circuit element section to the second power path.

[0014] Since power is supplied to the conductive intermediate path via the first and fourth circuit element sections even if current flows from the conductive intermediate path via the second circuit element section to the second power path, the vehicle's control unit can suppress a voltage drop in the second power storage unit. This can also suppress a voltage rise in the first power storage unit that would be caused by a voltage drop in the second power storage unit, which in turn can, for example, suppress deterioration in the first power storage unit.

[0015] [4] In the vehicle's control unit according to [3], the control unit increases the power supplied by the voltage conversion unit via the fourth circuit element section to the conductive intermediate path to a value that is greater than the power supplied by the conductive intermediate path via the second circuit element section to the second power path.

[0016] The vehicle's control unit can supply more power to the conductive intermediate path even if current flows from the conductive intermediate path through the second circuit element section to the second power path. Therefore, the vehicle's control unit can more reliably supply power to the second conductive path while simultaneously ensuring a charging current to the second power storage unit.

[0017] [5] In the vehicle's own control unit according to one of [2] to [4], when a voltage of the power storage unit is less than a predetermined lower limit voltage, the control unit causes the voltage conversion unit to start the first conversion operation so that a voltage to be applied to the fourth power path reaches a first target value, and thereby switches on the third circuit element section and off the fourth circuit element section and, If the voltage of the power storage unit is a final charging voltage that is higher than or equal to the lower limit voltage, the control unit causes the voltage conversion unit to perform the first conversion operation, so that the voltage to be applied to the fourth power path reaches a second target value that is lower than the first target value, thereby switching off the third circuit element section and switching on the fourth circuit element section.

[0018] The vehicle's own control unit can charge the power storage unit with power from the voltage conversion unit if the voltage of the power storage unit is lower than the lower limit voltage, and can supply power to the second power storage unit with a lower output voltage if the power storage unit reaches the final charging voltage.

[0019] [6] In the vehicle's control unit according to [5], if a predetermined fault detection condition is not met, if a voltage of the first power path is less than or equal to a first threshold value, the control unit causes the voltage conversion unit to perform the first conversion operation by switching off the third circuit element section and switching on the fourth circuit element section, thereby allowing a current to flow from the first power path via the first circuit element section to the third power path, and a current to flow from the conductive intermediate path via the second circuit element section to the second power path, and, If the fault detection condition is met, when the voltage of the first power path is less than or equal to the first threshold, the control unit switches on the third circuit element section, switches off the fourth circuit element section and causes the voltage conversion unit to perform the second conversion operation, thereby interrupting a current flow from the third power path via the first circuit element section to the first power path and interrupting a current flow from the second power path via the second circuit element section to the conductive intermediate path.

[0020] If the fault detection condition is not met, even though the voltage of the first power path has dropped to a value less than or equal to the first threshold, the vehicle's control unit can subject power from the power source unit to voltage conversion by the voltage conversion unit to supply the converted voltage towards the conductive intermediate path, thereby supplying power from the second power storage unit to the second power path via the second circuit element section. Conversely, if the fault detection condition is met, the vehicle's control unit can subject power from the power storage unit to voltage conversion by the voltage conversion unit to supply the converted voltage to the second power path, thereby interrupting any reverse flow towards the first power path.

[0021] [7] In the vehicle's control unit according to [6], the second circuit element section is configured to interrupt current flow between the conductive intermediate path and the second power path via the second circuit element section in both directions when the second circuit element section is switched off, and to allow current to flow from the conductive intermediate path via the second circuit element section to the second power path when the second circuit element section is switched on. the control unit controls the switching on / off of at least the second circuit element section and, If the system transitions from a state where the fault detection condition is not met to a state where the fault detection condition is met, if the voltage of the first power path is less than or equal to the first threshold, the control unit keeps the second circuit element section switched on before and after the transition, the control unit switches on the third circuit element section and switches off the fourth circuit element section after the transition, causing the voltage conversion unit to perform the second conversion operation, thereby interrupting the current flow from the third power path through the first circuit element section to the first power path, and if the voltage conversion unit meets a predetermined operating condition after the transition, the control unit switches off the second circuit element section.

[0022] If the voltage of the first power path is less than or equal to the first threshold and the state changes to one in which the fault detection condition is not met, the vehicle's control unit can activate the second circuit element section to quickly supply power from the second power storage unit to the second power path. If the state changes from one in which the fault detection condition is not met to one in which the fault detection condition is met, when the voltage of the first power path is less than or equal to the first threshold, the vehicle's control unit can, after the change, supply power whose voltage has been adjusted by the second conversion operation to the second power path via the third power path, thereby preventing a reverse flow towards the first power path.Since the vehicle's control unit can keep the second circuit element section switched on before and after the switchover, it is also possible to maintain the power supply from the second power storage unit via the second circuit element section to the second power path even if the output of the voltage conversion unit rises slowly after the switchover. Furthermore, if the voltage conversion unit meets a predetermined operating condition after the switchover, the vehicle's control unit can switch off the second circuit element section to restrict the discharge path from the path of the second circuit element section and the third power path to the third power path.

[0023] [8] In the vehicle's control unit according to [6] or [7], the fault determination condition includes the condition that a current flows from the third power path through the first circuit element section to the first power path, If no current flows from the third power path through the first circuit element section to the first power path when the voltage of the first power path is less than or equal to the first threshold, the control unit, by switching off the third circuit element section and switching on the fourth circuit element section, causes the voltage conversion unit to perform the first conversion operation, thereby allowing a current to flow from the first power path through the first circuit element section to the third power path, and the control unit allows a current to flow from the conductive intermediate path through the second circuit element section to the second power path, and, If a current flows from the third power path through the first circuit element section to the first power path, when the voltage of the first power path is less than or equal to the first threshold, the control unit switches on the third circuit element section and switches off the fourth circuit element section, causing the voltage conversion unit to perform the second conversion operation, thereby interrupting a current flow from the third power path through the first circuit element section to the first power path.

[0024] If the voltage of the first power path is less than or equal to the first threshold, the vehicle's control unit can confirm that no current is flowing through the first circuit element section to the first power path, i.e., that a ground fault in the first power path is not very likely, and then cause the voltage conversion unit to perform the first conversion operation to charge the second power storage unit. The vehicle's control unit can then discharge power through the second circuit element section in parallel with the power input to the second power storage unit resulting from the first conversion operation. Conversely, if a current is flowing through the first circuit element section to the first power path and the voltage of the first power path is less than or equal to the first threshold, i.e.,If it is highly probable that a ground fault has occurred in the first power path, the vehicle's control unit can interrupt the current flow through the first circuit element section to the first power path and prevent the ground fault from affecting the third power path. By causing the voltage conversion unit to perform the second conversion operation, it is possible to supply power to the second power path at a voltage adapted by the voltage conversion unit, thereby suppressing the effect of the ground fault.

[0025] [9] In the vehicle's control unit according to one of [6] to [8], the fault determination condition includes the condition that the voltage of the first power path is less than or equal to a second threshold which is less than the first threshold, If the voltage of the first power path is less than or equal to the first threshold and greater than the second threshold, the control unit, by switching off the third circuit element section and switching on the fourth circuit element section, causes the voltage conversion unit to perform the first conversion operation, thereby allowing a current to flow from the first power path through the first circuit element section to the third circuit element section, and the control unit allows a current to flow from the conductive intermediate path through the second circuit element section to the second power path, and, If the voltage of the first power path is less than or equal to the second threshold, the control unit switches on the third circuit element section and switches off the fourth circuit element section, causing the voltage conversion unit to perform the second conversion operation and thereby interrupting a current flow from the third power path via the first circuit element section to the first power path.

[0026] If the voltage of the first power path is less than or equal to the first threshold, the vehicle's control unit can confirm that the voltage is greater than the second threshold, i.e., that the voltage of the first power path is not too low, and then cause the voltage conversion unit to perform the first conversion operation to charge the second power storage unit. The vehicle's control unit can then discharge power through the second circuit element section in parallel with the power supply to the second power storage unit resulting from the first conversion operation. Conversely, if the voltage of the first power path is less than or equal to the second threshold, i.e.,If the voltage of the first power path is too low, it is possible to interrupt the current flow through the first circuit element section to the first power path. Thus, even if a ground fault occurs in the first power path, it is possible to prevent the ground fault from affecting the third power path. By causing the voltage conversion unit to perform the second conversion operation, it is then possible to supply power to the second power path at a voltage adjusted by the voltage conversion unit, thereby suppressing the effect of the voltage drop in the first power path.

[0027]

[10] In the vehicle's own control unit according to one of [6] to [9], the fault determination condition includes the condition that a predetermined fault signal is output to the vehicle's own control unit from an external device that is not the vehicle's own control unit, If the voltage of the first power path is less than or equal to the first threshold and the fault signal is not output by the external device, the control unit, by switching off the third circuit element section and switching on the fourth circuit element section, causes the voltage conversion unit to perform the first conversion operation, thereby allowing a current to flow from the first power path through the first circuit element section to the third power path, and the control unit allows a current to flow from the conductive intermediate path through the second circuit element section to the second power path, and, If the voltage of the first power path is less than or equal to the first threshold and the fault signal is output by the external device, the control unit switches on the third circuit element section and switches off the fourth circuit element section, causing the voltage conversion unit to perform the second conversion operation, thereby interrupting a current flow from the third power path via the first circuit element section to the first power path.

[0028] If the voltage of the first power path is less than or equal to the first threshold, the vehicle's control unit can confirm that no fault signal has been issued by the external device and then cause the voltage conversion unit to perform the first conversion operation to charge the second power storage unit. The vehicle's control unit can then discharge power through the second circuit element section in parallel with the power supply to the second power storage unit resulting from the first conversion operation. However, if a fault signal is generated when the voltage of the first power path is less than or equal to the first threshold, it is possible to cause the voltage conversion unit to perform the second conversion operation, thereby interrupting the current flow through the first circuit element section to the first power path.Accordingly, even if a ground fault or the like occurs in the first power path, when a fault signal is generated, it is possible to supply power to the second power path, the voltage of which has been adapted by the voltage conversion unit, thereby suppressing the effect of the fault signal.

[0029]

[11] The vehicle's control unit according to one of [1] to

[10] has: a fifth circuit element section capable of allowing a current to flow from the third power path to the second power path and of interrupting a current flow from the second power path to the third power path.

[0030] By causing the voltage conversion unit to perform the second conversion operation, whereby the fifth circuit element section allows a current to flow from the third power path to the second power path, the vehicle's own control unit can supply power to the second power path and apply a desired voltage to the third power path. First embodiment 1. Brief description of the vehicle's own system

[0031] Fig. Figure 1 shows a vehicle-specific system. Figure 2 shows the system in the vehicle. Fig. The vehicle-integrated system 2 shown in Figure 1 comprises a vehicle-integrated power source system 3 and a load 101. The vehicle-integrated system 2 is a system that supplies power to the load 101 using the vehicle-integrated power source system 3 and operates the load 101.

[0032] Load 101 is an electrical component installed in a vehicle. Load 101 is operational when it receives power from the vehicle's own power source system 3. The type of load 101 is not restricted. Various known vehicle components can be used as load 101. Load 101 can consist of multiple electrical components or be a single electrical component.

[0033] The vehicle's power source system 3 is a system that supplies power to the load 101. The vehicle's power source system 3 uses a power source unit 91 or a power storage unit 92 as a power supply source to supply power to the load 101. The vehicle's power source system 3 can supply power to the load 101 from the power source unit 91, and if the power supply from the power source unit 91 is interrupted, for example, due to a fault in it, then the vehicle's power source system 3 can supply power to the load 101 from the power storage unit 92. Depending on the circumstances, the power storage unit 92 can also be used as a supply source to supply power to the load 101 even if the power supply from the power source unit 91 to the load 101 is not interrupted. 2. Overview of the vehicle's own power source system

[0034] The vehicle's own power source system 3 comprises the power source unit 91, the power storage unit 92, a vehicle-specific control unit 10, and the like. It should be noted that in the Fig. In the representative example shown in Figure 1, a first power path 81, a second power path 82, a third power path 83, a fourth power path 84, a fifth power path 85, and the like are included as components of the vehicle's own control unit 10. However, the first power path 81, the second power path 82, the third power path 83, the fourth power path 84, and the fifth power path 85 can also be wholly or partially elements outside the vehicle's own control unit 10.

[0035] The power source unit 91 is a vehicle-integrated power source that can supply power to the load 101. The power source unit 91 is configured as a known vehicle-integrated power storage unit, for example, as a lead-acid battery. The power source unit 91 can also be formed by a battery that is not a lead-acid battery (e.g., a lithium-ion battery or another type of battery) and can include power source means that are not a battery instead of or in addition to a battery. In the example in Fig. 1 is the positive electrode-side terminal of the power source unit 91 in an embodiment in which it is short-circuited to the first power path 81. The negative electrode-side terminal of the power source unit 91 is electrically connected to ground in an embodiment in which it is short-circuited to earth. The power source unit 91 applies a constant DC voltage to the first power path 81. The voltage applied by the power source unit 91 to the first power path 81 may deviate slightly from the aforementioned constant value.

[0036] The power storage unit 92 is a power source that is distinct from the power source unit 91. The power storage unit 92 is a power source that serves as a power input source at least when the power input from the power source unit 91 is interrupted. The power storage unit 92 is formed by a known power storage device, for example, an electrical double-layer capacitor (EDLC). The power storage unit 92 can also be formed by a capacitor that is not an electrical double-layer capacitor and can include other storage devices (for example, a battery) instead of or in addition to a capacitor. In the example in Fig. 1. The positive electrode-side connection of the power storage unit 92 is electrically connected to the fifth power path 85 in an embodiment in which it is short-circuited. The negative electrode-side connection of the power storage unit 92 is electrically connected to ground in an embodiment in which it is short-circuited. The output voltage of the power storage unit 92 (the voltage applied by the power storage unit 92 to the fifth power path 85) can be greater than, less than, or equal to the output voltage of the power source unit 91 (the voltage applied by the power source unit 91 to the first power path 81).

[0037] The power storage unit 92 comprises a first power storage unit 92A and a second power storage unit 92B. The second power storage unit 92B is located on a side with a lower potential than the first power storage unit 92A and is connected in series with the first power storage unit 92A. The positive electrode terminal of the first power storage unit 92A forms the positive electrode terminal of the power storage unit 92. In an embodiment in which it is short-circuited to the positive electrode terminal of the second power storage unit 92B, the negative electrode terminal of the first power storage unit 92A is electrically connected to the positive electrode terminal of the second power storage unit 92B. The negative electrode terminal of the second power storage unit 92B forms the negative electrode terminal of the power storage unit 92.

[0038] In this description, unless otherwise specified, "voltage" refers to a voltage relative to earth potential (e.g., 0 V) ​​and is the potential difference to earth potential. For example, the voltage applied to the first power path 81 is the potential difference between the potential of the first power path 81 and earth potential.

[0039] The output voltage of the power source unit 91 is applied to the first power path 81. The first power path 81 forms part or all of the power supply path between the power source unit 91 and a first circuit element section 21. In an embodiment where it is short-circuited to the positive electrode terminal of the power source unit 91, one end of the first power path 81 is electrically connected to the positive electrode terminal of the power source unit 91. In the example in Fig. 1 is another end of the first power path 81 in an embodiment in which it is connected to an end of the first circuit element section 21 (in the example in Fig. 1. The first power path 81 is electrically connected to the source terminal (which serves as one end of a semiconductor switch forming the first circuit element section 21) and is short-circuited at one end. The first power path 81 may be equipped with a relay or a fuse. The first power path 81 ensures, for example, that the potentials at the positive electrode terminal of the power source unit 91 and at one end of the first circuit element section 21 are equal or substantially equal.

[0040] The second power path 82 is a path for supplying power supplied by the first power path 81 to the load 101. The second power path 82 forms part or all of the power supply path between a fifth circuit element section 25 and the load 101. One end of the second power path 82 is electrically connected to another end of the fifth circuit element section 25 (in the example in Fig. 1 the drain terminal, which serves as another end of a semiconductor switch 25B). Another end of the second power path 82 is electrically connected to the load 101 in an embodiment in which it is short-circuited to one end of the load 101. A second other end of the second power path 82 is connected to another end of the second circuit element section 22 (in the example in Fig. The second power path 82 is electrically connected to the other end of the second circuit element section 22 (where the drain terminal, which serves as the other end of a semiconductor switch 22B, is short-circuited). The second power path 82 may be equipped with a relay or a fuse. The second power path 82 ensures, for example, that the potentials at the other end of the fifth circuit element section 25, the other end of the second circuit element section 22, and one end of the load 101 are equal or substantially equal.

[0041] The third power path 83 is a power path that differs from the first power path 81 and the second power path 82. The third power path 83 is provided on the side of the voltage conversion unit 30 with the first power path 81 and on the side of the voltage conversion unit 30 with the second power path 82. One end of the third power path 83 is, in an embodiment, connected to another end of the first circuit element section 21 (in the example in Fig. 1. The drain terminal, which serves as the other end of a semiconductor switch forming the first circuit element section 21), is electrically connected to the other end of the first circuit element section 21. Another end of the third power path 83 is, in an embodiment in which it is short-circuited to one end of the voltage conversion unit 30, electrically connected to one end of the voltage conversion unit 30. A second other end of the third power path 83 is, in an embodiment in which it is short-circuited to one end of the fifth circuit element section 25 (in the example in Fig. The third power path 83, for example, ensures that the potentials at the other end of the first circuit element section 21, at one end of the fifth circuit element section 25, and at one end of the voltage conversion unit 30 are equal or substantially equal.

[0042] The fourth power path 84 is a power path that differs from the first power path 81, the second power path 82, and the third power path 83. The fourth power path 84 is provided on the side of the voltage conversion unit 30 with the power storage unit 92. In an embodiment where it is short-circuited to another end of the voltage conversion unit 30, one end of the fourth power path 84 is connected to the other end of the voltage conversion unit 30. In an embodiment where it is connected to an end of the third circuit element section 23 (in the example in Fig. 1. The source terminal, which serves as one end of a semiconductor switch forming the third circuit element section 23, is electrically connected to one end of the third circuit element section 23. A second other end of the fourth power path 84 is, in an embodiment, connected to one end of the fourth circuit element section 24 (in the example in Fig. 1. The drain terminal, which serves as one end of a semiconductor switch forming the fourth circuit element section 24, is short-circuited and electrically connected to one end of the fourth circuit element section 24. The fourth power path 84, for example, ensures that the potentials at the other end of the voltage conversion unit 30, at one end of the third circuit element section 23, and at one end of the fourth circuit element section 24 are equal or substantially equal.

[0043] The fifth power path 85 is a power path that differs from the first power path 81, the second power path 82, the third power path 83, and the fourth power path 84. One end of the fifth power path 85 is, in an embodiment, connected to another end of the third circuit element section 23 (in which in Fig. In the example shown in Figure 1, the drain terminal (which serves as the other end of the semiconductor switch forming the third circuit element section 23) is short-circuited and electrically connected to the other end of the third circuit element section 23. In an embodiment in which it is short-circuited to the positive electrode-side terminal of the power storage unit 92, another end of the fifth power path 85 is electrically connected to the positive electrode-side terminal of the power storage unit 92. The fifth power path 85 ensures, for example, that the potentials at the other end of the third circuit element section 23 and the positive electrode-side terminal of the power storage unit 92 are equal or substantially equal.

[0044] A conductive intermediate path 89 is provided between the first power storage unit 92A and the second power storage unit 92B. In an embodiment in which it is short-circuited to the negative electrode terminal of the first power storage unit 92A, one end of the conductive intermediate path 89 is electrically connected to the negative electrode terminal of the first power storage unit 92A. In an embodiment in which it is short-circuited to the positive electrode terminal of the second power storage unit 92B, another end of the conductive intermediate path 89 is electrically connected to the positive electrode terminal of the second power storage unit 92B. In an embodiment in which it is short-circuited to another end of the fourth circuit element section 24 (in which in Fig. In the example shown in Figure 1, the source terminal (which serves as the other end of the semiconductor switch forming the fourth circuit element section 24) is electrically connected to the other end of the fourth circuit element section 24. A third other end of the conductive intermediate path 89 is, in an embodiment in which it is short-circuited to an end of the second circuit element section 22 (in the example in Figure 1), electrically connected to the other end of the fourth circuit element section 24. Fig. 1. The drain terminal (which serves as one end of the semiconductor switch 22A) is short-circuited and is electrically connected to one end of the second circuit element section 22. The conductive intermediate path 89 ensures, for example, that the potentials at the negative electrode-side terminal of the first power storage unit 92A, the positive electrode-side terminal of the second power storage unit 92B, the other end of the fourth circuit element section 24, and one end of the second circuit element section 22 are equal or substantially equal. 3. Details of the vehicle's own control unit

[0045] The vehicle control unit 10 is a device used in the vehicle's system 2 and controls a power supply from the power storage unit 92. The vehicle control unit 10 is a backup control unit that can control a backup operation for outputting power from the power storage unit 92. The vehicle control unit 10 comprises the first power path 81, the second power path 82, the third power path 83, the fourth power path 84, the fifth power path 85, a control unit 16, the voltage conversion unit 30, the first circuit element section 21, the second circuit element section 22, the third circuit element section 23, the fourth circuit element section 24, the fifth circuit element section 25, voltage sensing units 41, 43 and 44, and the like.

[0046] In the representative example in Fig. In the first circuit element section 21, the first circuit element section 21 is formed by a semiconductor switch. The second circuit element section 22 is formed by two semiconductor switches 22A and 22B. The third circuit element section 23 is formed by a semiconductor switch. The fourth circuit element section 24 is formed by a semiconductor switch. The fifth circuit element section 25 is formed by two semiconductor switches 25A and 25B. In the example in Fig. 1 are the semiconductor switches that form the first circuit element section 21, the second circuit element section 22, the third circuit element section 23, the fourth circuit element section 24 and the fifth circuit element section 25, n-channel field-effect transistors (FETs).

[0047] The first circuit element section 21 is configured to allow current to flow from the first power path 81 to the third power path 83 (i.e., the side of the voltage conversion unit 30) and to interrupt current flow from the third power path 83 (i.e., the side of the voltage conversion unit 30) to the first power path 81. In the example in Fig. 1. The drain of the first circuit element section 21 is electrically connected to the third power path 83 in such a way that it is short-circuited to it, and the source of the second circuit element section 21 is electrically connected to the first power path 81 in such a way that it is short-circuited to it. When the first circuit element section 21 is switched on, current is allowed to flow through the first circuit element section 21 in both directions. When the first circuit element section 21 is switched off, current flow from the third power path 83 through the first circuit element section 21 to the first power path 81 is interrupted.

[0048] The second circuit element section 22 can allow a current to flow from the conductive intermediate path 89 to the second power path 82. The second circuit element section 22 can interrupt a current flow from the second power path 82 to the conductive intermediate path 89. The semiconductor switches 22A and 22B, which form the second circuit element section 22, are connected to each other in opposite orientations. In the example in Fig. In state 1, the drain of semiconductor switch 22A is short-circuited to the conductive intermediate path 89, the drain of semiconductor switch 22B is short-circuited to the second power path 82, and the source of semiconductor switch 22A and the source of semiconductor switch 22B are short-circuited to each other. A state in which the second circuit element section 22 is off means that both semiconductor switches 22A and 22B are off. When the second circuit element section 22 is off, current flow through the second circuit element section 22 is interrupted in both directions; that is, current flow from the second power path 82 through the second circuit element section 22 to the conductive intermediate path 89, as well as current flow from the conductive intermediate path 89 through the second circuit element section 22 to the second power path 82, is interrupted.A state in which the second circuit element section 22 is switched on means that both semiconductor switches 22A and 22B are switched on. When the second circuit element section 22 is switched on, current is allowed to flow through the second circuit element section 22 in both directions; that is, current flow is permitted both from the second power path 82 to the conductive intermediate path 89 and from the conductive intermediate path 89 to the second power path 82.

[0049] The third circuit element section 23 is provided between the fourth power path 84 and the fifth power path 85. In other words, the third circuit element section 23 is provided between the voltage conversion unit 30 and the power storage unit 92. The third circuit element section 23 interrupts current flow from the fifth power path 85 through itself to the fourth power path 84 when it is off. The third circuit element section 23 allows current to flow from the fifth power path 85 through itself to the fourth power path 84 when it is on. When the third circuit element section 23 is on, current flow through the third circuit element section 23 is permitted in both directions. When the third circuit element section 23 is on, the voltage of the fourth power path 84 is equal to the voltage of the power storage unit 92.In other words, when the third circuit element section 23 is switched on, the output voltage of the power storage unit 92 is applied to the fourth power path 84.

[0050] The fourth circuit element section 24 is provided in parallel to the arrangement in which the third circuit element section 23 and the first power storage unit 92A are connected in series. When switched off, the fourth circuit element section 24 interrupts the current flow from the fourth power path 84 through itself to the conductive intermediate path 89. When switched on, the fourth circuit element section 24 allows a current to flow from the fourth power path 84 through itself to the conductive intermediate path 89. When the fourth circuit element section 24 is switched on, current flow through the fourth circuit element section 24 is permitted in both directions. When the fourth circuit element section 24 is switched on, the voltage of the fourth power path 84 is equal to the voltage of the second power storage unit 92B.In other words, when the fourth circuit element section 24 is switched on, the output voltage of the second power storage unit 92B is applied to the fourth power path 84.

[0051] The fifth circuit element section 25 can allow current to flow from the third power path 83 (i.e., the side of the voltage conversion unit 30) to the second power path 82. The fifth circuit element section 25 can also interrupt current flow from the second power path 82 to the third power path 83 (i.e., the side of the voltage conversion unit 30). The semiconductor switches 25A and 25B, which form the fifth circuit element section 25, are connected to each other in opposite orientations. In the example in Fig. In state 1, the drain of semiconductor switch 25A is short-circuited to the third power path 83, the drain of semiconductor switch 25B is short-circuited to the second power path 82, and the source of semiconductor switch 25A and the source of semiconductor switch 25B are short-circuited to each other. A state in which the fifth circuit element section 25 is off means that both semiconductor switches 25A and 25B are off. When the fifth circuit element section 25 is off, current flow through the fifth circuit element section 25 is interrupted in both directions; that is, current flow from the second power path 82 to the third power path 83 (i.e., the side of the voltage conversion unit 30) and current flow from the third power path 83 (i.e., the side of the voltage conversion unit 30) to the second power path 82 is interrupted.A state in which the fifth circuit element section 25 is switched on means that both semiconductor switches 25A and 25B are switched on. When the fifth circuit element section 25 is switched on, current is allowed to flow through the fifth circuit element section 25 in both directions; that is, current flow is allowed both from the second power path 82 to the third power path 83 (i.e., the side of the voltage conversion unit 30) and from the side of the third power path 83 (i.e., the side of the voltage conversion unit 30) to the second power path 82.

[0052] The voltage conversion unit 30 is formed by a known voltage conversion circuit, for example a DC-DC converter. In the example in Fig. 1. The voltage conversion unit 30 performs a voltage conversion between the third power path 83 and the fourth power path 84. The voltage conversion unit 30 is a device that performs a first conversion operation, in which a voltage applied to the third power path 83 is converted to either boost or undershoot the voltage, and the output voltage is applied to the fourth power path 84, and a second conversion operation, in which a voltage applied to the fourth power path 84 is converted to either boost or undershoot the voltage, and the output voltage is applied to the third power path 83. Thus, the voltage conversion unit 30 performs voltage conversions in both directions. The operation of the voltage conversion unit 30 is controlled by the control unit 16.

[0053] The control unit 16 controls the first circuit element section 21, the second circuit element section 22, the third circuit element section 23, the fourth circuit element section 24, the fifth circuit element section 25, and the voltage conversion unit 30. The control unit 16 has an information processing unit with an information processing function, a calculation function, a control function, and the like. One or more units can be used to control the first circuit element section 21, the second circuit element section 22, the third circuit element section 23, the fourth circuit element section 24, the fifth circuit element section 25, and the voltage conversion unit 30.

[0054] Voltage sensing unit 41 is a circuit that outputs a detected value (e.g., an analog voltage value) to the control unit 16, indicating the voltage applied to the first power path 81. Voltage sensing unit 43 is a circuit that outputs a detected value (e.g., an analog voltage value) to the control unit 16, indicating the voltage applied to the third power path 83. Voltage sensing unit 44 is a circuit that outputs a detected value (e.g., an analog voltage value) to the control unit 16, indicating the voltage applied to the fourth power path 84.

[0055] The control unit 16 can determine the output voltage of the power storage unit 92 based on the detected value of the voltage detection unit 44 with the third circuit element section 23 switched on and the fourth circuit element section 24 switched off. The control unit 16 can determine the output voltage of the second power storage unit 92B based on the detected value of the voltage detection unit 44 with the third circuit element section 23 switched off and the fourth circuit element section 24 switched on. 4. Operation of the vehicle's own control unit

[0056] The control unit 16 switches on the first circuit element section 21 and the fifth circuit element section 25 when the vehicle is started. This ensures, as described in Fig. As shown in Figure 2, the second power path 82 receives power from the power source unit 91 via the first circuit element section 21 and the fifth circuit element section 25. It is noted that the control unit 16 keeps the second circuit element section 22 in the off state even after the vehicle has started. The control unit 16 can detect that the vehicle has started by receiving a signal indicating the on / off state of a starter switch or by receiving a signal output by an external ECU when the vehicle is started. The starter switch is an ignition switch, circuit breaker, or the like.

[0057] Furthermore, if the voltage of the power storage unit 92 is lower than a predetermined lower limit voltage, the control unit 16 causes the voltage conversion unit 30 to perform the first conversion operation so that the voltage to be applied to the fourth power path 84 reaches a first target value, thereby switching on the third circuit element section 23 and off the fourth circuit element section 24. This results in, as in Fig. As shown in Figure 2, the power from the power source unit 91 undergoes voltage conversion by the voltage conversion unit 30 and is supplied to the power storage unit 92, thus charging the power storage unit 92. The lower limit voltage is at least 0 V. The first target value is a value greater than the lower limit voltage. The first target value can be greater than the nominal voltage of the load 101.

[0058] If the voltage of the power storage unit 92 is a charging end voltage that is higher than or equal to the lower limit voltage, the control unit 16 switches the third circuit element section 23 to the off state and the fourth circuit element section 24 to the on state, and changes the target voltage of the voltage conversion unit 30 from the first target value to a second target value. In other words, if the voltage of the power storage unit 92 is the charging end voltage, the control unit 16 causes the voltage conversion unit 30 to perform the first conversion operation, so that the voltage to be applied to the fourth power path 84 is the second target value, which is lower than the first target value, and thereby switches off the third circuit element section 23 and on the fourth circuit element section 24. This results in, as in Fig. As shown in Figure 3, the power from the power source unit 91 undergoes voltage conversion by the voltage conversion unit 30 and is supplied to the second power storage unit 92B via the fourth circuit element section 24. The control unit 16 waits while maintaining this situation. The final charging voltage can be greater than or equal to the lower limit voltage. The final charging voltage can also be less than or equal to the first target value.

[0059] The control unit 16 can charge the second power storage unit 92B without charging the entire power storage unit 92 if the voltage of the power storage unit 92 is at least the lower limit voltage when the vehicle is started. In other words, if the voltage of the power storage unit 92 is at least the lower limit voltage, the control unit 16 can cause the voltage conversion unit 30 to perform the first conversion operation, such that the voltage to be applied to the fourth power path 84 is the second target value, which is lower than the first target value, thereby switching off the third circuit element section 23 and switching on the fourth circuit element section 24.

[0060] If the voltage of the first power path 81 is above the first threshold and below an overvoltage threshold that is greater than the first threshold, then the control unit 16 performs the operations described above (in particular, an operation in which power is supplied to the second power path 82 via the fifth circuit element section 25, and an operation in which power is supplied to the power storage unit 92 or the second power storage unit 92B).

[0061] If the voltage of the first power path 81 is at least the predetermined overvoltage threshold, the control unit 16 causes the voltage conversion unit 30 to perform the first conversion operation, switching on the first circuit element section 21, the second circuit element section 22, the third circuit element section 23, the fourth circuit element section 24, and the fifth circuit element section 25. This ensures that if the voltage of the first power path 81 rises to a voltage higher than or equal to the overvoltage threshold, as described in Fig. As shown in Figure 4, the power from the power source unit 91 undergoes voltage conversion by the voltage conversion unit 30 and is supplied to the second power path 82 via the fourth circuit element section 24 and the second circuit element section 22. The control unit 16 increases the power supplied by the voltage conversion unit 30 via the fourth circuit element section 24 towards the conductive intermediate path 89 to a value greater than the power supplied to the second power path 82 via the second circuit element section 22.

[0062] If a predetermined fault detection condition is not met and the voltage of the first power path 81 is equal to or less than the first threshold, the control unit 16 causes the voltage conversion unit 30 to perform the first conversion operation, switching on the first circuit element section 21, the second circuit element section 22, the third circuit element section 23, the fourth circuit element section 24, and the fifth circuit element section 25. This results in, as described in Fig. As shown in Figure 4, power from the power source unit 91 undergoes voltage conversion by the voltage conversion unit 30 and is supplied to the second power path 82 via the fourth circuit element section 24 and the second circuit element section 22. The control unit 16 increases the power supplied by the voltage conversion unit 30 via the fourth circuit element section 24 towards the conductive intermediate path 89 to a value greater than the power to be supplied to the second power path 82 via the second circuit element section 22.

[0063] If the fault detection condition is met and the voltage of the first power path 81 is equal to or less than the first threshold, the control unit 16 causes the voltage conversion unit 30 to perform the second conversion operation, switching off the first circuit element section 21, the second circuit element section 22, the third circuit element section 23, the fourth circuit element section 24, and the fifth circuit element section 25. This results in, as described in Fig. As shown in Figure 6, power from the power storage unit 92 is subjected to voltage conversion by the voltage conversion unit 30 and supplied to the second power path 82 via the fifth circuit element section 25.

[0064] Specifically, if the state changes from the state in which the fault detection condition is not met to the state in which it is met, when the voltage of the first power path 81 is equal to or less than the first threshold, the control unit 16 keeps the second circuit element section 22 in the switched-on state before and after the change. This ensures, as described in Fig. As shown in Figure 5, power is supplied to the second power path 82 from the second power storage unit 92B via the second circuit element section 22. After the switchover, the control unit 16 switches off the first circuit element section 21, switches on the second circuit element section 22, switches on the third circuit element section 23, switches off the fourth circuit element section 24, and switches off the fifth circuit element section 25, causing the voltage conversion unit 30 to perform the second conversion operation. If the voltage conversion unit 30 meets a predetermined operating condition after the switchover, the control unit 16 switches on the fifth circuit element section 25. This results in, as shown in Figure 5, the second circuit element section 25 being switched on. Fig. As shown in Figure 6, power from the power storage unit 92 undergoes voltage conversion by the voltage conversion unit 30 and is supplied to the second power path 82 via the fifth circuit element section 25. Additionally, the control unit 16 switches off the second circuit element section 22.

[0065] The predetermined operating condition can be, for example, that the output voltage of the voltage conversion unit 30 has reached a predetermined operating start voltage, or that a predetermined time has elapsed since the aforementioned change, or it can be any other condition.

[0066] The fault detection condition described above may include the condition that a current flows from the voltage conversion unit 30 through the first circuit element section 21 in the direction of the first power path 81. The fault detection condition may also include the condition that the voltage of the first power path 81 is less than or equal to a second threshold value that is lower than the first threshold value. The fault detection condition may also include the condition that a predetermined fault signal is output to the vehicle's own control unit 10 from an external device other than the vehicle's own control unit 10. 5. Examples of beneficial effects

[0067] By causing the voltage conversion unit 30 to perform the first conversion operation, whereby the first circuit element section 21 allows a current to flow from the first power path 81 to the third power path 83, the vehicle's own control unit 10 can charge the power storage unit 92 and apply a desired voltage to the fourth power path 84. Likewise, by causing the voltage conversion unit 30 to perform the second conversion operation, whereby the fifth circuit element section 25 allows a current to flow from the third power path 83 to the second power path 82, the vehicle's own control unit 10 can supply power to the second power path 82 and apply a desired voltage to the third power path 83.In other words, the vehicle's control unit 10 can adjust a charging voltage when charging the power storage unit 92 and a discharge voltage when discharging the power storage unit 92 with a simpler design, and in some cases, the first circuit element section 21 can interrupt a current flow from the third power path 83 to the first power path 81. Furthermore, it is possible to discharge the second power storage unit 92B via a path that is not the path on which the voltages are adjusted by the voltage conversion unit 30, since the second circuit element section 22 is provided and can allow a current to flow from the conductive intermediate path 89 between the first power storage unit 92A and the second power storage unit 92B to the second power path 82.Furthermore, in some cases it is possible to interrupt the current flow from the second power path 82 via the second circuit element section 22 to the second power storage unit 92B, since the second circuit element section 22 can interrupt the current flow from the second power path 82 to the conductive intermediate path 89. Moreover, according to the configuration in which the second power storage unit 92B is discharged via the second circuit element section 22, the output voltage is lower than in the configuration in which the power storage unit 92 is discharged directly. Therefore, it is easier to prevent the voltage applied to the load 101 from exceeding the nominal voltage of the load 101.

[0068] The vehicle's own control unit 10 can selectively supply power from the voltage conversion unit 30 to the power storage unit 92 or - bypassing the first power storage unit 92A - to the second power storage unit 92B.

[0069] Since the power is supplied to the conductive intermediate path 89 via the first circuit element section 21 and the fourth circuit element section 24 even if a current flows from the conductive intermediate path 89 via the second circuit element section 22 to the second power path 82, the vehicle's own control unit 10 can suppress a voltage drop in the second power storage unit 92B. This can also suppress a voltage rise in the first power storage unit 92A that would be caused by the voltage drop in the second power storage unit 92B, which in turn can, for example, suppress deterioration in the first power storage unit 92A.

[0070] The vehicle's own control unit 10 can supply a greater power to the conductive intermediate path 89 even if a current flows from the conductive intermediate path 89 via the second circuit element section 22 to the second power path 82. Therefore, the vehicle's own control unit 10 can supply power to the second power path 82 more reliably and simultaneously ensure a charging current to the second power storage unit 92B.

[0071] The vehicle's own control unit 10 can charge the power storage unit 92 with power from the voltage conversion unit 30 when the voltage of the power storage unit 92 is lower than the lower limit voltage, and can supply power to the second power storage unit 92B with a lower output voltage when the power storage unit 92 reaches the final charging voltage.

[0072] If the fault detection condition is not met, even though the voltage of the first power path 81 has dropped to a value less than or equal to the first threshold, the vehicle's control unit 10 can subject power from the power source unit 91 to voltage conversion by the voltage conversion unit 30 in order to supply the converted voltage towards the conductive intermediate path 89, thereby supplying power from the second power storage unit 92B to the second power path 82 via the second circuit element section 22. Conversely, if the fault detection condition is met, the vehicle's control unit 10 can subject the power from the power storage unit 92 to voltage conversion by the voltage conversion unit 30 in order to supply the converted voltage to the second power path 82, thereby interrupting a reverse flow towards the first power path 81.

[0073] If the voltage of the first power path 81 is less than or equal to the first threshold value and the state changes to the state in which the fault detection condition is not met, the vehicle's control unit 10 can switch on the second circuit element section 22 to quickly supply power from the second power storage unit 92B to the second power path 82. If the state changes from the state in which the fault detection condition is not met to the state in which the fault detection condition is met when the voltage of the first power path 81 is less than or equal to the first threshold value, the vehicle's control unit 10 can, after the change, supply power whose voltage has been adjusted by the second conversion operation to the second power path 82 via the third power path 83, thereby preventing a reverse flow towards the first power path 81.Since the vehicle's control unit 10 can keep the second circuit element section 22 switched on before and after the switchover, it is also possible to maintain the power supply from the second power storage unit 92B via the second circuit element section 22 to the second power path 82 even if the output of the voltage conversion unit 30 rises slowly after the switchover. Furthermore, if the voltage conversion unit 30 meets a predetermined operating condition after the switchover, the vehicle's control unit 10 can switch off the second circuit element section 22 to restrict the discharge path from the path of the second circuit element section 22 and the third power path 83 to the third power path 83.

[0074] In the embodiment in which the fault detection condition includes the condition that a current flows from the voltage conversion unit 30 via the first circuit element section 21 in the direction of the first power path 81, the following effects can be achieved: If the voltage of the first power path 81 is less than or equal to the first threshold value, the vehicle's own control unit 10 confirms that no current flows via the first circuit element section 21 to the first power path 81, i.e., that it is not very likely that a ground fault has occurred in the first power path 81, and then causes the voltage conversion unit 30 to perform the first conversion operation in order to charge the second power storage unit 92B.Then, in parallel with the supply of power towards the second power storage unit 92B, the vehicle's own control unit 10 can discharge power via the second circuit element section 22 due to the first conversion operation. On the other hand, if a current flows via the first circuit element section 21 to the first power path 81 when the voltage of the first power path 81 is less than or equal to the first threshold value, i.e., if it is very likely that a ground fault has occurred in the first power path 81, the vehicle's own control unit 10 can interrupt the current flow via the first circuit element section 21 to the first power path 81 and prevent the ground fault from affecting the third power path 83.By causing the voltage conversion unit 30 to perform the second conversion operation, it is possible to supply power to the second power path 82, the voltage of which has been adapted by the voltage conversion unit 30, thereby suppressing the effect of the earth fault.

[0075] In the embodiment where the fault detection condition includes the condition that the voltage of the first power path 81 is less than or equal to a second threshold that is lower than the first threshold, the following effects can be achieved: If the voltage of the first power path 81 is less than or equal to the first threshold, the vehicle's control unit 10 can confirm that the voltage is greater than the second threshold, i.e., that the voltage of the first power path 81 is not too low, and then cause the voltage conversion unit 30 to perform the first conversion operation to charge the second power storage unit 92B. The vehicle's control unit 10 can then discharge power via the second circuit element section 22 in parallel with the power supply to the second power storage unit 92B due to the aforementioned first conversion operation.If, on the other hand, the voltage of the first power path 81 is less than or equal to the second threshold value, i.e., if the voltage of the first power path 81 is too low, it is possible to interrupt the current flow through the first circuit element section 21 to the first power path 81. Thus, even if a ground fault occurs in the first power path 81, it is possible to prevent the ground fault from affecting the third power path 83. By causing the voltage conversion unit 30 to perform the second conversion operation, it is then possible to supply power to the second power path 82, the voltage of which has been adjusted by the voltage conversion unit 30, thereby suppressing the effect of the voltage drop in the first power path 81.

[0076] In the embodiment where the fault detection condition includes the condition that a predetermined fault signal is output to the vehicle's own control unit 10 from an external device other than the vehicle's own control unit 10, the following effects can be achieved: If the voltage of the first power path 81 is less than or equal to the first threshold value, the vehicle's own control unit 10 can confirm that no fault signal has been output by the external device and then cause the voltage conversion unit 30 to perform the first conversion operation to charge the second power storage unit 92B. The vehicle's own control unit 10 can then discharge power via the second circuit element section 22 as a result of the first conversion operation, in parallel with the supply of power to the second power storage unit 92B.If, on the other hand, a fault signal is generated when the voltage of the first power path 81 is less than or equal to the first threshold, then it is possible to cause the voltage conversion unit 30 to perform the second conversion operation, thereby interrupting the current flow through the first circuit element section 21 to the first power path 81. Accordingly, even if a ground fault or the like occurs in the first power path 81 when a fault signal is generated, it is possible to supply power to the second power path 82, the voltage of which has been adjusted by the voltage conversion unit 30, thereby suppressing the effect of the fault signal.

[0077] By causing the voltage conversion unit 30 to perform the second conversion operation, wherein the fifth circuit element section 25 allows a current to flow from the voltage conversion unit 30 to the second power path 82, the vehicle's own control unit 10 can supply power to the second power path 82 and thereby apply a desired voltage to the third power path 83. Other embodiments

[0078] The present disclosure is not limited to the embodiments described in the preceding description with reference to the drawings. For example, the features of the embodiments described above or below may be combined in any way, provided they do not contradict each other. Furthermore, any feature of the embodiments described above or below may be omitted unless it is expressly stated as an essential feature. In addition, the embodiments described above may be modified as follows.

[0079] In the aforementioned embodiments, the power storage unit 92 is provided outside the vehicle's own control unit 10, but it is also possible to have the power storage unit 92 contained in the vehicle's own control unit 10.

[0080] The fifth circuit element section 25 can also be omitted. In other words, no element needs to be arranged between the third power path 83 and the second power path 82. For example, the third power path 83 and the second power path 82 can be configured to be short-circuited.

[0081] Although the first circuit element section 21 in the embodiment described above comprises a single FET, the present disclosure is not limited to this example. For example, the embodiment according to Fig. 7(A) can be used and the second circuit element section 21 can be formed only by a diode 191. In this case, a conductive path 181A can be electrically connected to the first power path 81 and a conductive path 181B can be the third power path 83. Alternatively, the configuration according to Fig. 7(B) and the first circuit element section 21 is a switching section in which a switching element 192A (e.g., a FET) and a diode 192B are connected in series. In this case, a conductive path 182A can be electrically connected to the first power path 81, and a conductive path 182B can be the third power path 83. Alternatively, the configuration according to Fig. 7(D) can be used and the first circuit element section 21 can be a switching section 194 formed by a known semiconductor switch that is not a FET or a mechanical relay. In this case, a conductive path 184A can be electrically connected to the first power path 81 and a conductive path 184B can be the third power path 83. Alternatively, the configuration according to Fig. 7(E) is used and the first circuit element section 21 is formed by two semiconductor switches 195A and 195B. In this case, a conductive path 185A can be electrically connected to the first power path 81 and a conductive path 185B can be the third power path 83. The two semiconductor switches 195A and 195B can, for example, be FETs and can be arranged such that their source terminals are short-circuited.

[0082] In the embodiments described above, the second circuit element section 22 has two FETs, but the configuration according to Fig. 7(A) can be used and the second circuit element section 22 can also be formed solely by the diode 191. In this case, the conductive path 181A can be electrically connected to the fourth power path 84 and the conductive path 181B can be electrically connected to the second power path 82. Alternatively, the configuration according to Fig. 7(B) and the second circuit element section 22 is a switching section in which the switching element 192A (e.g., the FET) and the diode 192B are connected in series. In this case, the conductive path 182A can be electrically connected to the fourth power path 84 and the conductive path 182B can be electrically connected to the second power path 82. Alternatively, the configuration according to Fig. 7(C) can be used and the second circuit element section 22 can only have the switching element 193 (e.g., the FET). In this case, the conductive path 183A can be electrically connected to the fourth power path 84 and the conductive path 183B can be electrically connected to the second power path 82. Alternatively, the configuration according to Fig. 7(D) and the second circuit element section 22 is the switching section 194, which is formed by a known semiconductor switch that is not a FET or a mechanical relay. In this case, the conductive path 184A can be electrically connected to the fourth power path 84 and the conductive path 184B can be electrically connected to the second power path 82.

[0083] Although the third circuit element section 23 in the embodiment described above has a single FET, the present disclosure is not limited to this example. Alternatively, the embodiment according to Fig. 7(D) can be used and the third circuit element section 23 can be the switching section 194, which is formed by a known semiconductor switch that is not a FET or a mechanical relay. In this case, the conductive path 184A can be the fourth power path 84 and the conductive path 184B can be the fifth power path 85. Alternatively, the configuration according to Fig. 7(E) and the third circuit element section 23 can also be formed by two semiconductor switches 195A and 195B. In this case, the conductive path 185A can be the fourth power path 84 and the conductive path 185B can be the fifth power path 85. The two semiconductor switches 195A and 195B can, for example, be FETs and can be arranged such that their source terminals are short-circuited.

[0084] Although the fourth circuit element section 24 in the embodiment described above has a single FET, the present disclosure is not limited to this example. Alternatively, the embodiment according to Fig. 7(D) can be used and the fourth circuit element section 24 can be the switching section 194, which is formed by a known semiconductor switch that is not a FET or a mechanical relay. In this case, the conductive path 184A can be electrically connected to the fourth power path 84 and the conductive path 184B can be electrically connected to the conductive intermediate path 89. Alternatively, the configuration according to Fig. 7(E) is used and the fourth circuit element section 24 is formed by two semiconductor switches 195A and 195B. In this case, the conductive path 185A can be electrically connected to the fourth power path 84 and the conductive path 185B can be electrically connected to the conductive intermediate path 89. The two semiconductor switches 195A and 195B can, for example, be FETs and can be arranged such that their source terminals are short-circuited.

[0085] In the aforementioned embodiments, the fifth circuit element section 25 is formed by two FETs; however, as in Fig. As shown in Figure 7(A), the fifth circuit element section 25 can also be formed solely by the diode 191. In this case, the conductive path 181A can be electrically connected to the third power path 83, and the conductive path 181B can be electrically connected to the second power path 82. Alternatively, the fifth circuit element section 25 can be formed as shown in Figure 7(A). Fig. Figure 7(B) shows a switching section in which the switching element 192A (e.g., the FET) and the diode 192B are connected in series. In this case, the conductive path 182A can be electrically connected to the third power path 83, and the conductive path 182B can be electrically connected to the second power path 82. Alternatively, as shown in Fig. As shown in Figure 7(C), the fifth circuit element section 25 may also only contain the switching element 193 (e.g., the FET). In this case, the conductive path 183A may be electrically connected to the third power path 83, and the conductive path 183B may be electrically connected to the second power path 82. Alternatively, the fifth circuit element section 25 may, as shown in Figure 7(C), only contain the switching element 193 (e.g., the FET). Fig. Figure 7(D) shows the switching section 194, which is formed by a known semiconductor switch that is not a FET or a mechanical relay. In this case, the conductive path 184A can be electrically connected to the third power path 83 and the conductive path 184B can be electrically connected to the second power path 82.

[0086] The embodiments disclosed herein are to be regarded in every respect as illustrative and not as limiting. The scope of the invention is not limited to the embodiments disclosed herein, but is defined by the claims, which are intended to include all modifications that are equivalent to the claims in meaning and scope. REFERENCE MARK LIST 2. Vehicle-specific system 3 vehicle-integrated power source system 10 vehicle-specific control units 16 Control unit 21 first circuit element section 22 second circuit element section 22A semiconductor switch 22B Semiconductor Switch 23 third circuit element section 24 fourth circuit element section 25 fifth circuit element section 25A semiconductor switch 25B Semiconductor Switch 30 voltage conversion units 41 Voltage detection unit 43 Voltage detection unit 44 Voltage detection unit 81 first performance path 82 second performance path 83 third performance path 84 fourth performance path 85 fifth performance path 89 conductive intermediate path 91 Power Source Unit 92 Power storage unit 92A first power storage unit 92B second power storage unit 101 Last 181A conductive path 181B conductive path 182A conductive path 182B conductive path 183A conductive path 183B conductive path 184A conductive path 184B conductive path 185A conductive path 185B conductive path 191 Diode 192A switching element 192B Diode 193 Switching element 194 Switching section 195A semiconductor switch 195B Semiconductor Switch QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2020 - 182 318 A

[0003]

Claims

[1] Vehicle control unit for use in a vehicle system comprising: a power source unit for supplying power; a power storage unit which is distinct from the power source unit; a first power path to which power is supplied from the power source unit; and a second power path which serves as a path for supplying power supplied from the first power path to a load, wherein the vehicle control unit is configured to control a power supply from the power storage unit, and comprising: a voltage conversion unit provided between the second power path and the power storage unit and configured to perform a first conversion operation in which a voltage applied to a third power path provided on one side of the second power path is converted and an output voltage is applied to a fourth power path provided on one side of the power storage unit, and a second conversion operation in which a voltage applied to the fourth power path is converted and an output voltage is applied to the third power path; a control unit designed to control the voltage conversion unit; and a first circuit element section capable of allowing a current to flow from the first power path to the third power path, and of interrupting a current flow from the third power path to the first power path, wherein the power storage unit comprises a first power storage unit and a second power storage unit, which is located on a side with a lower potential than the first power storage unit and is connected in series with the first power storage unit and The vehicle's own control unit further comprises a second circuit element section capable of allowing a current to flow from a conductive intermediate path between the first power storage unit and the second power storage unit to the second power path, and of interrupting a current flow from the second power path to the conductive intermediate path. [2] Vehicle-specific control unit according to claim 1, further comprising: a third circuit element section provided between the fourth power path and a fifth power path, to which an output voltage of the power storage unit is applied; and a fourth circuit element section provided in parallel to an arrangement in which the third circuit element section and the first power storage unit are connected in series, wherein the third circuit element section is configured to interrupt current flow from the fifth power path to the fourth power path via the third circuit element section when the third circuit element section is switched off, and to allow current flow from the fifth power path via the third circuit element section to the fourth power path when the third circuit element section is switched on, the fourth circuit element section is configured to interrupt current flow from the fourth power path through the fourth circuit element section to the conductive intermediate path when the fourth circuit element section is switched off, and to allow current flow from the fourth power path through the fourth circuit element section to the conductive intermediate path when the fourth circuit element section is switched on, when the control unit switches on the third circuit element section, switches off the fourth circuit element section and causes the voltage conversion unit to perform the first conversion operation, power is supplied from the voltage conversion unit to the power storage unit and, When the control unit switches off the third circuit element section, switches on the fourth circuit element section and causes the voltage conversion unit to perform the first conversion operation, power is supplied from the voltage conversion unit to the second power storage unit via the fourth circuit element section. [3] Vehicle-specific control unit according to claim 2, wherein the control unit, by switching off the third circuit element section and switching on the fourth circuit element section, causes the voltage conversion unit to perform the first conversion operation, thereby allowing a current to flow from the first power path via the first circuit element section to the third power path, and allowing a current to flow from the conductive intermediate path via the second circuit element section to the second power path. [4] Vehicle-specific control unit according to claim 3, wherein the control unit increases the power to be supplied by the voltage conversion unit via the fourth circuit element section to the conductive intermediate path to a value that is greater than the power to be supplied by the conductive intermediate path via the second circuit element section to the second power path. [5] Vehicle-specific control unit according to one of claims 2 to 4, wherein, if a voltage of the power storage unit is less than a predetermined lower limit voltage, the control unit causes the voltage conversion unit to start the first conversion operation, so that a voltage to be applied to the fourth power path reaches a first target value, thereby switching on the third circuit element section and switching off the fourth circuit element section and, If the voltage of the power storage unit is a final charging voltage that is higher than or equal to the lower limit voltage, the control unit causes the voltage conversion unit to perform the first conversion operation, so that the voltage to be applied to the fourth power path reaches a second target value that is lower than the first target value, thereby switching off the third circuit element section and switching on the fourth circuit element section. [6] Vehicle-specific control unit according to claim 5, wherein, if a predetermined fault detection condition is not met, when a voltage of the first power path is less than or equal to a first threshold value, the control unit causes the voltage conversion unit to perform the first conversion operation by switching off the third circuit element section and switching on the fourth circuit element section, thereby allowing a current to flow from the first power path through the first circuit element section to the third power path, and allowing a current to flow from the conductive intermediate path through the second circuit element section to the second power path, and, If the fault detection condition is met, when the voltage of the first power path is less than or equal to the first threshold, the control unit switches on the third circuit element section and switches off the fourth circuit element section, causing the voltage conversion unit to perform the second conversion operation, thereby interrupting a current flow from the third power path via the first circuit element section to the first power path and interrupting a current flow from the second power path via the second circuit element section to the conductive intermediate path. [7] Vehicle-specific control unit according to claim 6, wherein the second circuit element section is configured to interrupt current flow between the conductive intermediate path and the second power path via the second circuit element section in both directions when the second circuit element section is switched off, and to allow current to flow from the conductive intermediate path via the second circuit element section to the second power path when the second circuit element section is switched on, the control unit controls the switching on / off of at least the second circuit element section and, If the system transitions from a state where the fault detection condition is not met to a state where the fault detection condition is met, if the voltage of the first power path is less than or equal to the first threshold, the control unit keeps the second circuit element section switched on before and after the transition, the control unit switches on the third circuit element section and switches off the fourth circuit element section after the transition, causing the voltage conversion unit to perform the second conversion operation, thereby interrupting the current flow from the third power path through the first circuit element section to the first power path, and if the voltage conversion unit meets a predetermined operating condition after the transition, the control unit switches off the second circuit element section. [8] Vehicle-specific control unit according to claim 6, wherein the fault determination condition includes the condition that a current flows from the third power path through the first circuit element section to the first power path, If no current flows from the third power path through the first circuit element section to the first power path when the voltage of the first power path is less than or equal to the first threshold, the control unit, by switching off the third circuit element section and switching on the fourth circuit element section, causes the voltage conversion unit to perform the first conversion operation, thereby allowing a current to flow from the first power path through the first circuit element section to the third power path, and the control unit allows a current to flow from the conductive intermediate path through the second circuit element section to the second power path, and, If a current flows from the third power path through the first circuit element section to the first power path, when the voltage of the first power path is less than or equal to the first threshold, the control unit switches on the third circuit element section and switches off the fourth circuit element section, causing the voltage conversion unit to perform the second conversion operation, thereby interrupting a current flow from the third power path through the first circuit element section to the first power path. [9] Vehicle-specific control unit according to claim 6, wherein the fault determination condition includes the condition that the voltage of the first power path is less than or equal to a second threshold which is lower than the first threshold, If the voltage of the first power path is less than or equal to the first threshold and greater than the second threshold, the control unit, by switching off the third circuit element section and switching on the fourth circuit element section, causes the voltage conversion unit to perform the first conversion operation, thereby allowing a current to flow from the first power path through the first circuit element section to the third circuit element section, and the control unit allows a current to flow from the conductive intermediate path through the second circuit element section to the second power path, and, If the voltage of the first power path is less than or equal to the second threshold, the control unit switches on the third circuit element section and switches off the fourth circuit element section, causing the voltage conversion unit to perform the second conversion operation and thereby interrupting a current flow from the third power path via the first circuit element section to the first power path. [10] Vehicle-specific control unit according to claim 6, wherein the fault determination condition includes the condition that a predetermined fault signal is output to the vehicle's own control unit from an external device that is not the vehicle's own control unit, If the voltage of the first power path is less than or equal to the first threshold and the fault signal is not output by the external device, the control unit, by switching off the third circuit element section and switching on the fourth circuit element section, causes the voltage conversion unit to perform the first conversion operation, thereby allowing a current to flow from the first power path through the first circuit element section to the third power path, and the control unit allows a current to flow from the conductive intermediate path through the second circuit element section to the second power path, and, If the voltage of the first power path is less than or equal to the first threshold and the fault signal is output by the external device, the control unit switches on the third circuit element section and switches off the fourth circuit element section, causing the voltage conversion unit to perform the second conversion operation, thereby interrupting a current flow from the third power path via the first circuit element section to the first power path. [11] Vehicle-specific control unit according to one of claims 1 to 4, further comprising: a fifth circuit element section capable of allowing a current to flow from the third power path to the second power path and of interrupting a current flow from the second power path to the third power path.

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