JP2011030362A - Vehicle power supply unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle power supply unit for integrating a power supply line of a first system and a power supply line of a second system and managing power. <P>SOLUTION: DC voltage lower than voltage of a high-voltage battery 20 is applied to a 42 V power supply line L1, and a first load 23 is connected to the line. DC voltage lower than voltage of the high-voltage battery 20 is applied to a 14 V power supply line L2 and a second load 26 is connected to the line. A first converter 21 is connected between the high-voltage battery 20 and the 42 V power supply line L1. A first power storage device 22 is connected to the 42 V power supply line L1. A bidirectional second converter 24 is connected between the 42 V power supply line L1 and the 14 V power supply line L2, and a second power storage device 25 is connected to the 14 V power supply line L2. A controller 27 controls the second converter 24 and transfers power between L1 and L2, when the battery 20 becomes abnormal. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a vehicle power supply device.

  FIG. 10 shows an example of a vehicle power supply system. In FIG. 10, a high power load (for example, a power steering motor) 102 is connected to the high voltage battery 100 via a high voltage → 42 volt converter 101, and the high voltage (for example, 240 volt) is stepped down to 42 volts to obtain the high power load 102. Supply. Further, a 12 volt battery 104 and a 14 volt load (for example, a wiper motor) 105 are connected to the high voltage battery 100 via a high voltage → 14 volt converter 103, and the high voltage (for example, 240 volt) is stepped down to 14 volt. The 104 and 14 volt loads 105 are supplied. Further, the 14-volt power supply line and the 42-volt power supply line are connected via the 14-volt → 42-volt backup converter 106, and the high-voltage battery 100 is reduced in capacity. The voltage is increased from 14 volts to 42 volts so that a large power load (for example, a power steering motor) 102 can be driven.

  Patent Document 1 discloses a vehicle control device including a motor that drives a vehicle, a fuel cell connected in parallel to the motor, and a capacitor. Specifically, a DC / DC converter is provided between the fuel cell and the capacitor, the input side of the converter is connected to the fuel cell, the output side is connected to the capacitor, and the output voltage of the DC / DC converter is controlled by the control means. Is controlled to change according to the vehicle speed.

JP 2007-181328 A

  However, in FIG. 10, the 42-volt power supply line and the 14-volt power supply line are not integrated. For example, the backup converter 106 can be used to back up the 14-volt system to the 42-volt system. The 14-volt system cannot be backed up from the bolt system.

  The present invention has been made under such a background, and an object of the present invention is to provide a vehicular power supply device capable of managing power by integrating a first power supply line and a second power supply line. Is to provide.

  In the first aspect of the present invention, a battery, a first power supply line to which a first DC voltage lower than the voltage of the battery is applied and a first load is connected, and a voltage of the battery A second power supply line to which a second low DC voltage is applied and a second load is connected; a first converter connected between the battery and the first power supply line; A first power storage device connected to a power supply line of one system; a bidirectional second converter connected between the power supply line of the first system and the power supply line of the second system; A second power storage device connected to two power supply lines; and when the battery is abnormal or when regenerative energy is generated from the load, the second converter is controlled to control the first power supply line and the first power supply line Between two power lines And gist further comprising a control means for causing the power transfer, the.

  According to the first aspect of the present invention, the first converter is connected between the battery and the first system power line, and the first power storage device is connected to the first system power line. . In addition, the bidirectional second converter is connected between the first power line and the second power line, and the second power storage device is connected to the second power line. . The control means controls the second converter to transfer power between the first system power line and the second system power line when the battery is abnormal or when regenerative energy is generated from the load.

Thereby, the power can be managed by integrating the power line of the first system and the power line of the second system.
According to a second aspect of the present invention, in the vehicle power supply device according to the first aspect, the control means is a state of charge of the first power storage device and the second power storage device when the battery is abnormal. The gist is to control the second converter so as to back up the power storage device in which the power is reduced by the power storage device that does not decrease.

  According to the second aspect of the present invention, mutual backup can be performed between the first power storage device in the first power supply line and the second power storage device in the second power supply line.

  According to a third aspect of the present invention, in the vehicle power supply device according to the first or second aspect, the control means monitors at least one of the voltage of the battery and the current of the battery, and the voltage of the battery and the battery The gist is to determine that the battery is abnormal when at least one of the currents falls below a specified value.

According to invention of Claim 3, abnormality of a battery can be determined correctly.
According to a fourth aspect of the present invention, in the vehicular power supply apparatus according to the first aspect, the control means uses the regenerative energy to generate the first power storage device and the second power when the regenerative energy is generated from the load. The gist is to control the second converter so as to charge the power storage device of the power storage device whose charge state is lowered.

  According to the fourth aspect of the present invention, the first power storage device in the first power line and the second power storage device in the second power line can be appropriately charged with regenerative energy.

  According to a fifth aspect of the present invention, in the vehicle power supply device according to the first or fourth aspect, the first converter is a bidirectional converter, and the control means generates regenerative energy from the load. The gist is to control the first converter to charge the battery whose state of charge has been reduced by the regenerative energy.

  According to the fifth aspect of the present invention, the battery can be charged with regenerative energy.

  According to the present invention, the power can be managed by integrating the power line of the first system and the power line of the second system.

The circuit block diagram of the vehicle power supply device in 1st Embodiment. The flowchart for demonstrating the effect | action of the vehicle power supply device in 1st Embodiment. The circuit block diagram of the power supply device for vehicles in a modification. The circuit block diagram of the vehicle power supply device in 2nd Embodiment. The flowchart for demonstrating the effect | action of the vehicle power supply device in 2nd Embodiment. The flowchart for demonstrating the effect | action of the vehicle power supply device in 2nd Embodiment. The circuit block diagram of the vehicle power supply device in 3rd Embodiment. The time chart for demonstrating the effect | action of the vehicle power supply device in 3rd Embodiment. The circuit block diagram of the power supply device for vehicles in a modification. The circuit block diagram for demonstrating background art.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a circuit configuration of a vehicle power supply device 10 according to this embodiment, and the power supply device 10 is mounted on a hybrid vehicle or the like.

  The power supply device 10 includes a high-voltage battery 20, a 42-volt power supply line L1 as a first power supply line, a 14-volt power supply line L2 as a second power supply line, a first converter 21, 1 power storage device 22, a bidirectional second converter 24, a second power storage device 25, and a controller 27 as control means.

  The output voltage of the high voltage battery 20 is, for example, 240 volts, and a 42 volt power supply line L1 is applied with 42 volts that is a first DC voltage lower than 240 volts that is the voltage of the high voltage battery 20, and a 14 volt power supply. The line L2 is applied with 14 volts, which is a second DC voltage lower than 240 volts, which is the voltage of the high voltage battery 20.

  The first converter 21 is connected between the positive terminal of the high-voltage battery 20 and the 42-volt power supply line L1 via the positive power supply line L3. The first converter 21 is a step-down DC-DC converter, which can step down and output the high voltage from the high-voltage battery 20 to 42 volts lower than that. Thus, the first converter 21 is a converter for converting from a high voltage (240 volts) to 42 volts, and is hereinafter referred to as a high voltage → 42 voltage converter 21. Note that the negative terminal of the high voltage battery 20 is grounded.

  The first power storage device 22 is connected to the 42-volt power supply line L1. A battery or a capacitor is used as the first power storage device 22. Further, a high power load 23 as a first load is connected to the 42 volt power supply line L1. The large power load 23 is, for example, a power steering motor.

  Further, a second converter 24 is connected between the 42 volt power supply line L1 and the 14 volt power supply line L2. The second converter 24 is a step-up / step-down DC-DC converter, which can step down and output 42 volts to a lower 14 volts, and boost 14 volts to a higher 42 volts. Can be output. Thus, the second converter 24 is a converter that can convert from 42 volts to 14 volts and bidirectionally from 14 volts to 42 volts, and hereinafter referred to as 42 volts ← → 14 volts bidirectional converter 24. That's it. Normally, 14 volts is made from 42 volts by the 42 volt ← → 14 volt bidirectional converter 24.

  A second power storage device 25 is connected to the 14-volt power supply line L2. A battery or a capacitor is used as the second power storage device 25. A 14-volt load 26 as a second load is connected to the 14-volt power supply line L2. The 14-volt load 26 is, for example, an engine ECU (engine electronic control unit).

  When applied to an electric vehicle (EV vehicle) instead of a hybrid vehicle, the 14-volt load 26 is, for example, a management ECU (management electronic control unit).

  The controller 27 inputs the inter-terminal voltage V3 in the high voltage battery 20. In addition, the controller 27 receives the terminal voltage V <b> 1 in the first power storage device 22. Further, the controller 27 inputs the inter-terminal voltage V <b> 2 in the second power storage device 25. The controller 27 monitors the inter-terminal voltages V1, V2, and V3. The controller 27 can control the 42 volt ← → 14 volt bidirectional converter 24.

Next, the operation of the power supply apparatus 10 configured as described above will be described.
FIG. 2 is a flowchart for explaining the processing contents executed by the controller 27.

  In FIG. 2, the controller 27 determines in step 100 whether or not the inter-terminal voltage V3 in the high voltage battery 20 is equal to or lower than a specified value. .

  On the other hand, if the inter-terminal voltage V3 in the high voltage battery 20 is equal to or lower than the specified value in step 100, the controller 27 determines that the high voltage battery 20 is abnormal and proceeds to step 101. In step 101, the controller 27 determines whether one of the inter-terminal voltage V1 in the first power storage device 22 and the inter-terminal voltage V2 in the second power storage device 25 is equal to or less than a specified value. The first and second power storage devices 22 and 25 are fully charged, and the process in FIG.

  On the other hand, in step 101, the controller 27 determines whether the first power storage device 22 or the terminal voltage V1 in the first power storage device 22 and the terminal voltage V2 in the second power storage device 25 are equal to or less than a specified value. The process proceeds to step 102 on the assumption that the second power storage device 25 is not sufficiently charged.

  If the inter-terminal voltage V1 in the first power storage device 22 is equal to or less than the specified value in step 102, the controller 27 performs an operation of converting the 42 volt ← → 14 volt bidirectional converter 24 from 14 volt to 42 volt in step 103. Make it. Thereby, electric power is supplied to the 1st electrical storage apparatus 22 and the large electric power load 23, and the large electric power load 23 can be driven (it can back up). Thereby, fail safe can be performed.

  On the other hand, if the controller 27 makes a negative determination in step 102, that is, if the inter-terminal voltage V <b> 2 in the second power storage device 25 is equal to or less than the specified value, in step 104, the 42 volt → 14 volt bidirectional converter 24 is changed to 42. The operation of converting from 14 volts to 14 volts is performed. Thereby, electric power is supplied to the second power storage device 25 and the 14-volt load 26, and the 14-volt load 26 can be driven (can be backed up).

  As described above, when the high voltage battery 20 becomes unusable during traveling, that is, when the high voltage battery 20 is abnormal, the 42-volt power supply line L1 and 14-volt are controlled by controlling the 42 volt ← → 14 volt bidirectional converter 24. Power is transferred to and from the system power supply line L2. As a result, the vehicle can be safely retracted using the energy in the first power storage device 22 connected to the 42 volt power supply line L1 and the energy in the second power storage device 25. At this time, the power storage device in which the state of charge of the first power storage device 22 and the second power storage device 25 is reduced can be backed up by the power storage device that does not decrease. Therefore, the necessary energy can be supplied to the necessary load regardless of the state of charge of first and second power storage devices 22 and 25 and battery 20.

  Specifically, when the power storage device (12 volt battery) is lifted while the vehicle is stopped, the engine cannot be started with the conventional system. However, in the present embodiment, energy can be supplied from the 42-volt first power storage device 22 to the 14-volt power supply line L2, so that the engine can be started.

As described above, according to the present embodiment, the following effects can be obtained.
(1) The first converter 21 is connected between the high-voltage battery 20 and the 42-volt power supply line L1, and the first power storage device 22 is connected to the 42-volt power supply line L1. Further, the bidirectional second converter 24 is connected between the 42 volt power supply line L1 and the 14 volt power supply line L2, and the second power storage device 25 is connected to the 14 volt power supply line L2. ing. When the high voltage battery 20 is abnormal, the controller 27 controls the second converter 24 to transfer power between the 42 volt power supply line L1 and the 14 volt power supply line L2. As a result, the power can be managed by integrating the 42-volt power supply line L1 and the 14-volt power supply line L2.

  (2) The controller 27 uses the second power storage device to back up the power storage device in which the charging state is reduced among the first power storage device 22 and the second power storage device 25 when the high voltage battery 20 is abnormal. The converter 24 is controlled. Thereby, mutual backup between the first power storage device 22 in the 42 volt power supply line L1 and the second power storage device 25 in the 14 volt power supply line L2 can be performed.

That is, bidirectional backup is possible between 14 volts and 42 volts. Further, the engine can be started when the second power storage device 25 is raised.
(3) The controller 27 monitors the voltage V3 of the high voltage battery 20, and determines that the high voltage battery 20 is abnormal when the voltage V3 falls below a specified value. Thereby, abnormality of the high voltage battery 20 can be determined accurately. Here, instead of the battery voltage, the battery current may be monitored, or both the battery voltage and current may be monitored. In short, it is preferable to monitor at least one of the battery voltage and the battery current and determine that the battery is abnormal when at least one of the battery voltage and the battery current falls below a specified value (others). The same applies to the above embodiment).

The configuration shown in FIG. 3 may be used instead of FIG. In FIG. 3, the power supply 10 includes a high voltage battery 20, a 14 volt power supply line L11 as a first power supply line, a 42 volt power supply line L12 as a second power supply line, and a first converter. 30, first power storage device 32, bidirectional second converter 31, second power storage device 35, 14 volt load 33 as the first load, and high power as the second load A load 36 and a controller 27 are provided. In FIG. 1, a high voltage → 42 volt converter 21 and a 42 volt ← → 14 volt bidirectional converter 24 are used. Instead, in FIG. 3, a high voltage → 14 volt converter 30 is used as the first converter 30 and a 14 volt →→ 42 volt bidirectional converter 31 is used as the second converter 31. The system configuration is such that the voltage is stepped down and boosted from 14 volts to 42 volts by the converter 31. The controller 27 inputs the inter-terminal voltage V3 in the high-voltage battery 20, the inter-terminal voltage V1 in the first power storage device 32, and the inter-terminal voltage V2 in the second power storage device 35. Then, the controller 27 controls the bidirectional converter 31 according to the V1 value, the V2 value, and the V3 value.
(Second Embodiment)
Next, the second embodiment will be described focusing on the differences from the first embodiment.

FIG. 4 shows the electrical configuration of the power supply device according to this embodiment.
In the first embodiment, the controller 27 controls the second converter 24 to transfer power between the 42 volt power supply line L1 and the 14 volt power supply line L2 when the high voltage battery 20 is abnormal. . On the other hand, in the present embodiment of FIG. 4, the controller 27 controls at least the second converter 24 when the regenerative energy is generated from the first and second loads 41 and 42, and the 42 volt power supply line L <b> 1. Power is transferred to and from the 14-volt power supply line L2.

  A bidirectional converter (first converter) 40 is used in this embodiment shown in FIG. 4 instead of the first converter 21 shown in FIG. The bidirectional converter 40 is a step-up / step-down DC-DC converter, which can step down a high voltage (240 volts) to a lower voltage of 42 volts and output it, and increase the voltage to 42 volts higher than that. The voltage can be boosted to a high voltage (240 volts) and output. Thus, the bidirectional converter 40 is a converter that can convert from high voltage to 42 volts and bidirectionally convert from 42 volts to high voltage, and is hereinafter referred to as high voltage ← → 42 volts bidirectional converter 40.

  Further, instead of the large power load 23 in FIG. 1, the large power load 41 is used in the present embodiment in FIG. 4 as the first load. The large power load 41 uses a traveling motor and generates regenerative energy (electromotive force). Similarly, instead of the 14-volt load 26 in FIG. 1, a 14-volt load 42 is used in the present embodiment in FIG. 4 as the second load. The 14-volt load 42 uses a motor and generates regenerative energy (electromotive force).

  The controller 27 can control the high voltage ← → 42 volt bidirectional converter (first converter) 40 and the 42 volt ← → 14 volt bidirectional converter (second converter) 24.

Next, the operation of the power supply device configured as described above will be described.
5 and 6 are flowcharts for explaining the processing contents executed by the controller 27.

  In FIG. 5, the controller 27 determines in step 200 whether or not the inter-terminal voltage V2 in the second power storage device 25 is equal to or higher than a specified value. If the voltage is lower than the specified value, no regenerative energy is generated in the 14-volt load 42. Then, the process of FIG.

  On the other hand, if the inter-terminal voltage V2 in the second power storage device 25 is greater than or equal to the specified value in step 200, the controller 27 proceeds to step 201 assuming that regenerative energy has been generated in the 14-volt load 42. In step 201, the controller 27 determines whether one of the inter-terminal voltage V1 in the first power storage device 22 and the inter-terminal voltage V3 in the high-voltage battery 20 is equal to or less than a specified value. The processing of FIG. 5 is terminated assuming that the device 22 and the high voltage battery 20 are sufficiently charged.

  On the other hand, in step 201, the controller 27 determines whether the first power storage device 22 or the high voltage battery 20 has a voltage V1 between the terminals of the first power storage device 22 or a voltage V3 between the terminals of the high voltage battery 20 that is less than or equal to a specified value. Since it is not fully charged, the routine proceeds to step 202.

  If the inter-terminal voltage V1 in the first power storage device 22 is equal to or less than the specified value in step 202, the controller 27 performs an operation of converting the 42 volt ← → 14 volt bidirectional converter 24 from 14 volt to 42 volt in step 203. Make it. As a result, the first power storage device 22 is charged with the regenerative energy generated by the 14-volt load 42.

  On the other hand, if the controller 27 makes a negative determination in step 202, that is, if the inter-terminal voltage V3 in the high-voltage battery 20 is equal to or less than a specified value, the controller 42 changes the 42-volt to 14-volt bidirectional converter 24 from 14 to 42 in step 204. The operation of converting to bolts is performed and the operation of converting the high voltage ← → 42-volt bidirectional converter 40 from 42 volts to high pressure is performed. Thereby, the high voltage battery 20 is charged with the regenerative energy generated by the 14-volt load 42.

  In FIG. 6, the controller 27 determines in step 300 whether or not the inter-terminal voltage V <b> 1 in the first power storage device 22 is equal to or higher than a specified value. Then, the process of FIG.

  On the other hand, if the inter-terminal voltage V1 in the first power storage device 22 is greater than or equal to the specified value in step 300, the controller 27 proceeds to step 301 because regenerative energy is generated in the large power load 41. In step 301, the controller 27 determines whether one of the inter-terminal voltage V2 in the second power storage device 25 and the inter-terminal voltage V3 in the high-voltage battery 20 is equal to or less than a specified value. The processing of FIG. 6 is terminated assuming that the device 25 and the high voltage battery 20 are sufficiently charged.

  On the other hand, in step 301, the controller 27 determines whether the second power storage device 25 or the high voltage battery 20 is in a state where either the terminal voltage V2 in the second power storage device 25 or the terminal voltage V3 in the high voltage battery 20 is equal to or less than a specified value. Since it is not fully charged, the routine proceeds to step 302.

  If the inter-terminal voltage V2 in the second power storage device 25 is equal to or less than the specified value in step 302, the controller 27 performs an operation of converting the 42 volt ← → 14 volt bidirectional converter 24 from 42 volt to 14 volt in step 303. Make it. As a result, the second power storage device 25 is charged with the regenerative energy generated by the large power load 41.

  On the other hand, if the controller 27 makes a negative determination in step 302, that is, if the inter-terminal voltage V3 in the high-voltage battery 20 is equal to or less than the specified value, in step 304 the high voltage ← → 42 volt bidirectional converter 40 is changed from 42 volts to a high voltage. Make the conversion work. Thereby, the high voltage battery 20 is charged with the regenerative energy generated by the high power load 41.

  Here, in the configuration shown in FIG. 10, the regenerative energy from the load 102 of the 24 volt system other than the 14 volt system cannot be stored in the 12 volt battery 104, but the regenerative energy from the load 102 is used in the 42 volt system. Is turned into heat with resistance and thrown away.

  In the present embodiment shown in FIGS. 4, 5, and 6, regenerative energy from any load (41, 42) is stored, and the regenerative energy can be prevented from being discarded as much as possible. That is, in FIG. 4, the power storage devices (22, 25) are provided in both the 42 volt power supply line L1 and the 14 volt power supply line L2, and the 42 volt power supply line L1 and the 14 volt power supply line L2 Bolt ← → 14-volt bidirectional converter 24 is provided. Further, a high voltage ← → 42 volt bidirectional converter 40 is also provided between the high voltage battery 20 and the 42 volt system power supply line L1. The regenerative energy from the 14-volt load 42 can be stored not only in the second power storage device 25 but also in the first power storage device 22 and further stored in the high-voltage battery 20. Similarly, the regenerative energy from the large power load 41 can be stored not only in the first power storage device 22 but also in the second power storage device 25 and the high voltage battery 20.

According to the above embodiment, the following effects can be obtained.
(1) The controller 27 controls the 42 volt ← → 14 volt bidirectional converter 24 to generate the 42 volt power supply line L1 and the 14 volt system when regenerative energy is generated from the load (high power load 41, 14 volt load 42). Since power is transferred to and from the power supply line L2, the power can be managed by integrating the 42 volt power supply line L1 and the 14 volt power supply line L2.

  (2) When the regenerative energy is generated from the load (41, 42), the controller 27 charges the power storage device in which the charge state of the first power storage device 22 and the second power storage device 25 is reduced by the regenerative energy. Therefore, the 42 volt ← → 14 volt bidirectional converter 24 is controlled. Thereby, the 1st electrical storage apparatus 22 in 42 volt system power supply line L1 and the 2nd electrical storage apparatus 25 in 14 volt system power supply line L2 can be charged appropriately by regenerative energy.

  (3) The high-voltage ← → 42-volt bidirectional converter 40 is a bidirectional converter, and the controller 27 is a high-voltage battery whose charging state is reduced by the regenerative energy when regenerative energy is generated from the load (41, 42). The high voltage ← → 42 volt bidirectional converter 40 is controlled to charge 20. Thereby, the high voltage battery 20 can also be charged by regenerative energy.

  That is, regenerative energy from either the large power load 41 or the 14-volt load 42 can be stored in the power storage device (22, 25) or the high-voltage battery 20. For example, even when the first power storage device 22 is fully charged and energy is regenerated from the large power load 41, the energy can be transmitted and charged to the high voltage battery 20 or the second power storage device 25 through the bidirectional converters 40 and 24. As a result, less regenerative energy is thrown away.

Note that a charger (alternator) 45 may be connected to the high voltage battery 20 as indicated by a virtual line in FIG. Further, instead of FIG. 4, as in the example described with reference to FIG. 3, a high voltage ← → 14 volt bidirectional converter 40 is used instead of the high voltage ← → 42 volt bidirectional converter 40, and a 42 volt ← → 14 volt bidirectional converter is used. The present invention may be applied when a 14 volt ← → 42 volt bidirectional converter is used instead of 24.
(Third embodiment)
Next, the third embodiment will be described focusing on the differences from the first embodiment.

FIG. 7 shows an electrical configuration of the power supply device according to this embodiment.
In FIG. 7, the first power storage device 22, the large power load 23, and the load 50 that needs to operate in an emergency are connected to the 42 volt power supply line L <b> 1. The load 50 that needs to operate even in an emergency is, for example, an electric brake motor.

  The first power storage device 22 can drive the load (electric brake motor) 50 in an emergency such as a disconnection, and a plurality of braking operations are possible in an emergency (abnormal). In addition, examples of the load 50 that needs to operate even in an emergency can include a power steering motor, and can perform a power steering operation for steering a vehicle even in an emergency (abnormal).

The function of the first power storage device 22 will be described in detail.
The first power storage device 22 functions as a power buffer for the load 50, and temporarily supplies power from the first power storage device 22 to the load 50 that consumes a large amount of power only for a short time. The output current specification of the bolt converter 21 can be lowered.

  Further, in FIG. 7, the first power storage device in the event of an emergency such as disconnection of a point indicated by point A (middle of the positive power supply line L3) and point B (14 volt load 26 side of the 14 volt system power supply line L2). When the energy stored in 22 is insufficient, as shown in FIG. 8 for the load 50 that needs to operate even in an emergency, for example, when starting the motor at the start of steering, the first power storage device 22 generates a large amount of power. (1500 W in FIG. 8) is supplied. Then, during steady operation after the motor is started, electric power (100 W in FIG. 8) is supplied from the second power storage device 25 to the load 50 through the 42 volt ← → 14 volt bidirectional converter 24. That is, energy is supplied from the second power storage device 25 through the backup converter (42 volt ← → 14 volt bidirectional converter 24) to the load 50 that needs to operate even in an emergency.

  As described above, conventionally, an emergency power storage device (battery, capacitor, etc.) has a single function. However, in this embodiment, the emergency power storage device can be used for multiple purposes. Moreover, it becomes possible to store the energy regenerated from the large power load 23 in the first power storage device 22, which has an energy saving effect.

  In addition, as shown in FIG. 9 instead of FIG. 7, if there is a converter (24) capable of converting from 42 volts to 14 volts, a load 60 that needs to operate in an emergency can be connected to the 14-volt system power line L2. Good. In this case, the second power storage in the event of an emergency such as disconnection of the point indicated by point C (in the middle of the positive power supply line L3) and point D (on the high power load 23 side in the 42-volt power supply line L1) in FIG. When the energy stored in the device 25 is insufficient, large power is supplied from the second power storage device 25 to the load 60 that needs to operate even in an emergency, for example, at the start of the motor at the start of steering. Then, during steady operation after starting the motor, electric power is supplied from the first power storage device 22 to the load 60 through the 42 volt ← → 14 volt bidirectional converter 24.

Next, the technical idea that can be grasped from the third embodiment will be described below together with the effects thereof.
Battery,
A first DC power line to which a first DC voltage lower than the voltage of the battery is applied and a first load is connected;
A second DC power line to which a second DC voltage lower than the voltage of the battery is applied and a second load is connected;
A first converter connected between the battery and a power line of the first system;
A first power storage device connected to the power line of the first system;
A bidirectional second converter connected between the first system power line and the second system power line;
A second power storage device connected to the power line of the second system;
With
For the motor, which is connected to the power line of the first system or the power line of the second system and needs to operate even in an emergency, the power for starting is connected to the same power line in an emergency. A power supply device for a vehicle, wherein the power supply device is supplied from the power storage device, and power for steady operation after startup is supplied from the second converter.

  Therefore, according to the present invention, it is possible to cope with an emergency by supplying power to a motor as a load that needs to operate even in an emergency.

  DESCRIPTION OF SYMBOLS 10 ... Vehicle power supply device, 20 ... High voltage battery, 21 ... 1st converter, 22 ... 1st electrical storage apparatus, 23 ... High power load (1st load), 24 ... 2nd converter, 25 ... 2nd Power storage device, 26 ... 14 volt load (second load), 27 ... controller, 30 ... first converter, 31 ... second converter, 32 ... first power storage device, 33 ... 14 volt load (first) ), 35 ... second power storage device, 36 ... first power load (second load), 40 ... first converter, 41 ... high power load (first load), 42 ... 14 volt load (first load) 2 load), L1... 42 volt power line, L2... 14 volt power line, L11... 42 volt power line, L12.

Claims (5)

Battery,
A first DC power line to which a first DC voltage lower than the voltage of the battery is applied and a first load is connected;
A second DC power line to which a second DC voltage lower than the voltage of the battery is applied and a second load is connected;
A first converter connected between the battery and a power line of the first system;
A first power storage device connected to the power line of the first system;
A bidirectional second converter connected between the first system power line and the second system power line;
A second power storage device connected to the power line of the second system;
Control means for controlling the second converter to transfer power between the first system power line and the second system power line when the battery is abnormal or when regenerative energy is generated from the load. When,
A vehicle power supply apparatus comprising:   The control means is configured to switch the second converter to back up a power storage device whose charge state is reduced among the first power storage device and the second power storage device when the battery is abnormal. The vehicle power supply device according to claim 1, wherein the vehicle power supply device is controlled.   The control means monitors at least one of the battery voltage and the battery current, and determines that the battery is abnormal when at least one of the battery voltage and the battery current falls below a specified value. The power supply device for vehicles according to claim 1 or 2 characterized by these.   The control means is configured to charge the power storage device in which a charge state of the first power storage device and the second power storage device is reduced by the regenerative energy when regenerative energy is generated from the load. The vehicle power supply device according to claim 1, wherein:   The first converter is a bidirectional converter, and the control means switches the first converter to charge the battery whose charging state has been lowered by the regenerative energy when regenerative energy is generated from the load. The vehicle power supply device according to claim 1 or 4, wherein the vehicle power supply device is controlled.

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