JP2015042510A - Hybrid vehicle power supply - Google Patents

Abstract

When power is supplied from an engine starting battery to a cell motor, an auxiliary power supply fails, and when power is supplied from the engine starting battery to in-vehicle electrical equipment via a resistor, the engine starting battery is A power supply device for a hybrid vehicle that can prevent a voltage drop from becoming larger is provided.
An engine starting battery for supplying electric power to a cell motor, an auxiliary power source for supplying electric power to an in-vehicle electrical equipment, and an engine, which are installed in a hybrid vehicle including a traveling motor and an engine. In a hybrid vehicle power supply device having a relay provided between a starter battery and an auxiliary power supply, provided between the engine starter battery and the auxiliary power supply and connected in parallel to the relay The ECU is configured such that the lower the SOC, which is the charged state of the battery for starting the engine, is set to a lower vehicle speed when starting the engine and the power consumption of the in-vehicle electrical equipment is reduced.
[Selection] Figure 3

Description

  The present invention relates to a power supply device for a hybrid vehicle equipped in a hybrid vehicle including a traveling motor and an engine.

  FIG. 8 shows a configuration of a conventional hybrid vehicle power supply device. The conventional hybrid vehicle power supply device shown in FIG. 8 is installed in a hybrid vehicle having a driving motor and an engine as drive sources, and has two power sources: an engine starting battery 2 and an auxiliary power source 4. It is a system equipped with.

More specifically, the hybrid vehicle power supply apparatus includes an engine starter battery 2 that supplies power to the cell motor 1 that starts the engine, an auxiliary power supply 4 that supplies power to the in-vehicle electrical equipment 3, and an engine starter. A relay 5 is provided between the battery 2 and the auxiliary power source 4.
The auxiliary power supply 4 is connected to various on-vehicle electrical equipment 3. The in-vehicle electrical equipment 3 is an electrical equipment related to vehicle control such as ABS (Antilock Brake System), ASC (Active Stability Control), EPS (Electric Power Steering) assist. The engine starting battery 2 is connected to the cell motor 1 via a relay 6.

  In this hybrid vehicle power supply device, when the relay 6 is closed, electric power is supplied from the engine starting battery 2 to the cell motor 1 as indicated by an arrow a, so that the cell motor 1 rotates. As a result, the engine is started by the rotation of the cell motor 1. The engine is started when the stopped vehicle is started or when the traveling vehicle is accelerated by the traveling motor.

  However, when electric power is supplied from the engine starting battery 2 to the cell motor 1 for starting the engine, a large amount of energy (current) flows through the cell motor 1 as indicated by an arrow a. Therefore, as shown in FIG. The voltage V decreases. And if this voltage drop is large, the vehicle-mounted electrical equipment 3 related to vehicle control, such as ABS, ASC, and EPS assist, will be reset (initialization).

  Therefore, while power is supplied from the engine starting battery 2 to the cell motor 1 and the cell motor 1 rotates, the voltage drop of the engine starting battery 2 is transmitted to the in-vehicle electrical equipment 3 by opening the relay 5. To prevent. While the relay 5 is open, the power source of the in-vehicle electrical equipment 3 is maintained by the auxiliary power source 4.

  In addition, there exists the following patent document 1 as a prior art document relevant to this invention.

JP 2013-56613 A

  In the conventional hybrid vehicle power source device shown in FIG. 8, as described above, the power source of the in-vehicle electrical equipment 3 is maintained by the auxiliary power source 4 while the relay 5 is open. However, when a failure occurs in the auxiliary power supply 4 as shown in FIG. 10, the power supply path of the in-vehicle electrical equipment 3 is lost while the relay 5 is open.

  Although the relay 5 is open for a short time when the cell motor 1 is rotating, if the power supply path of the in-vehicle electrical equipment 3 is lost during that time, the on-vehicle related to vehicle control such as ABS, ASC, EPS assist, etc. The power supply path of the electrical equipment 3 is also lost. For this reason, when the power supply path | route of the vehicle-mounted electrical equipment 3 failed during vehicle travel, vehicle control became impossible and it was anxious about having a bad influence on vehicle travel.

  Therefore, in order to solve such a problem, although details will be described later, it was considered to connect a resistor in parallel to the relay 5 (see FIG. 1). If a resistor is connected in parallel to the relay 5, even if the auxiliary power supply 4 breaks down while the relay 5 is open, power is supplied from the engine starting battery 2 to the in-vehicle electrical equipment 3 via the resistor. Therefore, it is possible to prevent a failure of the power supply path of the in-vehicle electrical equipment 3.

  However, the amount of energy flowing from the engine starting battery 2 to the in-vehicle electrical equipment 3 via the resistor in this state depends on the state of charge (SOC) of the engine starting battery 2. For this reason, when power is supplied from the engine starting battery 2 to the cell motor 1 to start the engine, if the SOC of the engine starting battery is low, if the power consumption of the in-vehicle electrical equipment 3 is large, the engine starting There was a concern that the voltage drop of the battery 2 would become larger. When the voltage drop of the engine starting battery 2 becomes larger, there is a concern about resetting the in-vehicle electrical equipment 3 related to vehicle control such as ABS, ASC, and EPS assist.

  Accordingly, in the present invention, in view of the above circumstances, when power is supplied from the engine starting battery to the cell motor, the auxiliary power supply fails, and power is also supplied from the engine starting battery to the in-vehicle electrical equipment via the resistor. It is an object of the present invention to provide a hybrid vehicle power supply device that can prevent the voltage drop of the engine starting battery from becoming larger.

A power source device for a hybrid vehicle according to a first aspect of the present invention that solves the above-described problem is provided in a hybrid vehicle including a traveling motor and an engine, and includes an engine starting battery that supplies electric power to a cell motor that starts the engine, and an in-vehicle electrical component In a hybrid vehicle power supply device comprising an auxiliary power source for supplying power to equipment, and a switch provided between the engine starting battery and the auxiliary power source,
A resistor provided between the engine starting battery and the auxiliary power source, and connected in parallel to the switch;
Control means for setting the vehicle speed when starting the engine to be lower and reducing the power consumption of the in-vehicle electrical equipment as the SOC of the battery for starting the engine is lower.

Further, the hybrid vehicle power supply device of the second invention is the hybrid vehicle power supply device of the first invention,
The control means is characterized in that when the SOC of the engine starting battery is determined to be lower than a first predetermined value, power consumption of EPS assist, which is the in-vehicle electrical equipment, is suppressed.

Further, the hybrid vehicle power supply device of the third invention is the hybrid vehicle power supply device of the second invention,
When the control means determines that the SOC of the engine starting battery is lower than a second predetermined value lower than the first predetermined value, the power consumption of the EPS assist, ABS, and ASC, which are the in-vehicle electrical equipment, is determined. It is characterized by suppressing.

  According to the hybrid vehicle power supply device of the present invention, the lower the SOC of the battery for starting the engine, the lower the vehicle speed when starting the engine and the lower the power consumption of the in-vehicle electrical equipment. When power is supplied from the engine starting battery to the cell motor, the auxiliary power supply fails, and when the power is supplied from the engine starting battery to the in-vehicle electrical equipment via the resistor, the engine starting battery It is possible to prevent the voltage drop from becoming larger. For this reason, the voltage drop of the engine starting battery becomes larger, and the concern that the in-vehicle electrical equipment related to vehicle control such as ABS, ASC, EPS assist is reset is reduced.

It is a figure which shows the structure of the power supply device for hybrid vehicles which concerns on the example of embodiment of this invention. It is a figure which shows the state which the failure of the power supply for auxiliary machines generate | occur | produced in the hybrid vehicle power supply device which concerns on the example of embodiment of this invention. It is a flowchart of the vehicle speed (cell motor ON speed) determination process at the time of engine starting in the hybrid vehicle power supply device according to the embodiment of the present invention. It is a figure which shows the specific example of the power supply for auxiliary machines in the hybrid vehicle power supply device which concerns on the embodiment of this invention. It is a figure which shows the specific example of the power supply for auxiliary machines in the hybrid vehicle power supply device which concerns on the embodiment of this invention. It is a figure which shows the specific example of the power supply for auxiliary machines in the hybrid vehicle power supply device which concerns on the embodiment of this invention. It is a figure which shows the specific example of the power supply for auxiliary machines in the hybrid vehicle power supply device which concerns on the embodiment of this invention. It is a figure which shows the structure of the conventional hybrid vehicle power supply device. It is a figure which shows the voltage fall of the battery for engine starting when a cell motor rotates. It is a figure which shows the state which the failure of the power supply for auxiliary machines generate | occur | produced in the conventional hybrid vehicle power supply device.

  Embodiments of the present invention will be described below in detail with reference to the drawings.

  The hybrid vehicle power supply device according to the embodiment of the present invention shown in FIG. 1 is mounted on a hybrid vehicle having a driving motor and an engine as drive sources, and a 12V engine starting battery 2 and The system is provided with two power sources, a 12V auxiliary power source 4.

More specifically, the hybrid vehicle power supply apparatus according to the present embodiment includes an engine starting battery 12 that supplies power to the cell motor 11 that starts the engine, and an auxiliary power supply 14 that supplies power to the in-vehicle electrical equipment 13. And a relay 15 (switch) provided between the engine starting battery 12 and the auxiliary power source 14, a resistor 17, and an ECU (Electronic Control Unit) 18 serving as control means.
The auxiliary power supply 14 is connected to various in-vehicle electrical equipment 3. A specific example of the auxiliary power supply 14 will be described later (FIGS. 4 to 7). The in-vehicle electrical equipment 13 is an electrical equipment related to vehicle control such as ABS, ASC, EPS assist and the like. The engine starting battery 12 is connected to the cell motor 11 via a relay 16.

  The resistor 17 is connected in parallel to the relay 15 between the engine starting battery 12 and the auxiliary power source 14. As a configuration in which the resistor 17 is combined with the relay 15 in parallel, an inrush current reduction relay (ICR relay) in which the resistor is combined with the relay in parallel can also be used.

  In this hybrid vehicle power supply device, when the relay 16 is closed by an open / close signal from the ECU 18, power is supplied from the engine starting battery 12 to the cell motor 11 as indicated by an arrow b, so that the cell motor 11 rotates. As a result, the engine is started by the rotation of the cell motor 11.

  However, when electric power is supplied from the engine starting battery 12 to the cell motor 11 for starting the engine, a large amount of energy (current) flows through the cell motor 1 as indicated by an arrow b, and thus a voltage drop of the engine starting battery 12 occurs. To do. And if this voltage drop is large, the vehicle-mounted electrical equipment 13 related to vehicle control, such as ABS, ASC, and EPS assist, will be reset (initialization).

  Therefore, while the power is supplied from the engine starting battery 12 to the cell motor 11 and the cell motor 11 rotates, the relay 15 is opened by an open / close signal from the ECU 18, so that the voltage drop of the engine starting battery 12 is reduced to the on-vehicle 13 is prevented from being transmitted. While the relay 15 is open, the power source of the in-vehicle electrical equipment 13 is maintained by the auxiliary power source 14.

In a state where the relay 15 is open, the engine starting battery 12 and the in-vehicle electrical equipment 13 are connected via the resistor 17.
In this state, the power of the engine starting battery 12 is more easily supplied to the cell motor 11 than the in-vehicle electrical equipment 13 by the resistance 17.
Even if the voltage of the engine starting battery 12 is lower than the voltage of the auxiliary power source 14 due to the rotational energy of the cell motor 11, the auxiliary power source 14 is connected to the cell motor 11 via the resistor 17. Therefore, it is possible to prevent the power of the auxiliary power supply 14 from being supplied to the cell motor 11 at once, and to secure a power supply path for the in-vehicle electrical equipment 13.

As shown in FIG. 2, when the auxiliary power supply 14 fails while the relay 17 is open, power cannot be supplied from the auxiliary power supply 14 to the in-vehicle electrical equipment 13.
However, since the in-vehicle electrical equipment 13 is connected to the engine starting battery 12 via the resistor 17, the power path of the in-vehicle electrical equipment 13 can be secured.
That is, even if the auxiliary power supply 14 fails when the relay 17 is open, power can be supplied from the engine starting battery 12 to the in-vehicle electrical equipment 13 via the resistor 17 as indicated by an arrow c. In-vehicle electrical equipment 13 does not cause power failure.
Further, since the engine starting battery 12 is connected to the in-vehicle electrical equipment 13 via the resistor 17, the electric power of the engine starting battery 12 is easily supplied to the cell motor 11 and does not hinder the engine starting. Since the engine can be started quickly, the time for supplying electric power from the engine starting battery 12 to the in-vehicle electrical equipment 13 via the resistor 17 becomes short, and the influence on the vehicle control can be prevented.

  However, when electric power is supplied from the engine starting battery 12 to the cell motor 11 to rotate the cell motor 11 (start the engine), the auxiliary power supply 14 fails and is mounted on the vehicle via the resistor 17 from the engine starting battery 12. When power is also supplied to the electrical equipment 13, the power required for the rotation of the cell motor 11 and the power required for the in-vehicle electrical equipment 13 overlap, so the load on the engine start battery 12 increases and the engine start battery The voltage drop of 12 tends to be further increased.

Since the engine starting battery 12 deteriorates over time, the larger the electric power supplied from the engine starting battery 12, the more the load on the engine starting battery 12 increases and the instantaneous voltage drop of the engine starting battery 12 decreases. There is a concern that the in-vehicle electrical equipment 13 may be reset due to the increase in the value.
In order to reduce such a concern, it is necessary to suppress power consumption that is a burden on the engine starting battery 12. Although the electric power required for the rotation of the cell motor 11 is constant, if the power consumption of the in-vehicle electrical equipment 13 can be reduced, the voltage drop of the engine starting battery 12 can be suppressed.

A vehicle generally requires all the electric power of actuators related to vehicle control when the vehicle speed is high, but does not reach a state where all actuators related to vehicle control operate when the vehicle speed is low.
Accordingly, when it is determined that the engine starter battery 12 has deteriorated over time (the SOC is low) and the voltage drop of the engine starter battery 12 is large, the vehicle speed at the time of engine start is lowered, and the in-vehicle electrical equipment 13 If the amount of electric power consumed is suppressed, the influence of the voltage drop of the engine starting battery 12 at the time of starting the engine can be mitigated. Thereby, the fear of reset of the vehicle-mounted electrical equipment 13 related to vehicle control such as ABS, ASC, and EPS assist can be suppressed, and the stability of vehicle control can be maintained.
Conversely, when it is determined that the engine start battery 12 is in a good state (SOC is high) and the voltage drop of the engine start battery 12 is small, sufficient power can be supplied from the engine start battery 12. Therefore, the vehicle speed when starting the engine can be increased.

  Specifically, the ECU 18 performs processing as shown in the flowchart of FIG. In addition, the codes | symbols S1-S12 were attached | subjected to each step (process) in the flowchart of FIG.

  When the process is started in step S1, first, the SOC of the engine starting battery 12 is detected in step S2. For example, as shown in FIG. 1, the ECU 18 detects the SOC of the engine starting battery 12 based on the voltage of the engine starting battery 12. However, the present invention is not limited to this, and the SOC of the engine starting battery 12 may be detected by other SOC detection means.

Subsequently, in step S3, it is determined whether or not the SOC of the engine starting battery 12 detected in step S2 is higher than 90% (first predetermined value).
As a result, when it is determined in step S3 that the SOC of the engine starting battery 12 is higher than 90%, the process proceeds to step S4. In step S4, the vehicle speed at the start of the engine is set to 30 km / h.
In this case, it is determined that the state of the engine starting battery 12 is good (SOC is high) and the voltage drop of the engine starting battery 12 is small. For this reason, suppression of the power consumption of the vehicle-mounted electrical equipment 13 is not performed.

  In step S5, the process is terminated, and the vehicle speed of the hybrid vehicle traveling by the traveling motor (that is, the vehicle speed detected by the vehicle speed sensor 19 shown in FIG. 1) has reached the vehicle speed of 30 km / h set in step S4. When the relay 16 is closed by an open / close signal from the ECU 18, power is supplied from the engine starting battery 12 to the cell motor 11 to rotate (ON) the cell motor 11. As a result, the engine is started by the rotation of the cell motor 11.

On the other hand, if it is determined in step S3 that the SOC of the engine starting battery 12 is 90% or less, the process proceeds to step S6.
In step S6, it is determined whether or not the SOC of the engine starting battery 12 detected in step S2 is higher than 60% (second predetermined value).
As a result, when it is determined in step S6 that the SOC of the engine starting battery 12 is higher than 60%, the process proceeds to step S7. In step S7, the vehicle speed at the start of the engine is set to 13 km / h. Thereafter, the process proceeds to step S8.
In this case, it is determined that the engine starting battery 12 has deteriorated over time (the SOC is low) and the voltage drop of the engine starting battery 12 is large.

  For this reason, in step S8, the power consumption of the in-vehicle electrical equipment 13 is suppressed by the power consumption suppression signal (FIG. 1) of the ECU 18. For example, by turning off the EPS assist of the in-vehicle electrical equipment 13 (in a standby state), the power consumption of the EPS assist is suppressed. That is, when the ECU 18 determines that the SOC of the engine starting battery 12 is lower than a first predetermined value (90% in the illustrated example), it suppresses the power consumption of the EPS assist that is the in-vehicle electrical equipment 13.

  In step S9, the process is terminated, and the vehicle speed of the hybrid vehicle traveling by the traveling motor (that is, the vehicle speed detected by the vehicle speed sensor 19 shown in FIG. 1) has reached the vehicle speed of 13 km / h set in step S7. When the relay 16 is closed by an open / close signal from the ECU 18, power is supplied from the engine starting battery 12 to the cell motor 11 to rotate (ON) the cell motor 11. As a result, the engine is started by the rotation of the cell motor 11.

If it is determined in step S6 that the SOC of the engine starting battery 12 is 60% or less, the process proceeds to step S10. In step S10, the vehicle speed at the start of the engine is set to 7 km / h. Then, it progresses to step S11.
In this case, it is determined that the engine starting battery 12 is further deteriorated with age (SOC is further lowered) and the voltage drop of the engine starting battery 12 is further increased.

  For this reason, in step S11, the power consumption of the in-vehicle electrical equipment 13 is further suppressed by the power consumption suppression signal (FIG. 1) of the ECU 18. For example, the EPS assist, ABS, ASC, and fan of the in-vehicle electrical equipment 13 are turned off (set to the standby state), thereby suppressing the power consumption of the EPS assist, ABS, ASC, and fan. That is, when the ECU 18 determines that the SOC of the engine starting battery 12 is lower than a second predetermined value (60% in the illustrated example) that is lower than the first predetermined value (90% in the illustrated example), the in-vehicle electrical equipment 13 The EPS assist, ABS, ASC, and fan power consumption are reduced.

  In step S12, the process is terminated, and the vehicle speed of the hybrid vehicle traveling by the travel motor (that is, the vehicle speed detected by the vehicle speed sensor 19 shown in FIG. 1) has reached the vehicle speed of 7 km / h set in step S10. When the relay 16 is closed by an open / close signal from the ECU 18, power is supplied from the engine starting battery 12 to the cell motor 11 to rotate (ON) the cell motor 11. As a result, the engine is started by the rotation of the cell motor 11.

Here, a specific example of the auxiliary power supply 14 will be described with reference to FIGS.
The hybrid vehicle power supply device shown in FIG. 4 includes a DCDC converter 21 as the auxiliary power supply 14. The DCDC converter 21 converts the voltage (115V) of the driving battery 22 for supplying power to the traveling motor into a voltage (12V) suitable for the in-vehicle electrical equipment 13.
The hybrid vehicle power supply device shown in FIG. 5 includes a DCDC converter 21 and a 12V auxiliary battery 23 as the auxiliary power supply 14.
The hybrid vehicle power supply device shown in FIG. 6 includes a 12V auxiliary battery 23 as the auxiliary power supply 14.
The hybrid vehicle power supply device shown in FIG. 7 includes a capacitor 24 as the auxiliary power supply 14.

As described above, according to the hybrid vehicle power supply device of the present embodiment, the lower the SOC that is the charged state of the engine starting battery 12, the lower the vehicle speed at the time of starting the engine and the in-vehicle electrical equipment 13. In order to suppress power consumption, when power is supplied from the engine starting battery 12 to the cell motor 11 in order to start the engine, the auxiliary power supply 14 breaks down and passes through the resistor 17 from the engine starting battery 12. Thus, when power is supplied also to the in-vehicle electrical equipment 13, it is possible to prevent the voltage drop of the engine starting battery 12 from becoming larger. For this reason, the voltage drop of the engine starting battery 12 is further increased, and the concern that the in-vehicle electrical equipment 13 related to vehicle control such as ABS, ASC, and EPS assist is reset is reduced.
This is the end of the description of the embodiment of the invention, but the invention is not limited to this embodiment. For example, in this embodiment, the circuit is opened and closed by a relay, but the present invention is not limited to this, and may be opened and closed by, for example, a button switch.

  TECHNICAL FIELD The present invention relates to a hybrid vehicle power supply device installed in a hybrid vehicle including a travel motor and an engine, and is used for auxiliary equipment when power is supplied from an engine start battery to a cell motor to start the engine. By preventing the voltage drop of the engine starting battery from becoming larger when the power supply fails and power is supplied from the engine starting battery to the in-vehicle electrical equipment via the resistor, the ABS, ASC This is useful when applied to reduce the concern that the on-vehicle electrical equipment related to vehicle control such as EPS assist will be reset.

DESCRIPTION OF SYMBOLS 11 Cell motor 12 Engine starting battery 13 In-vehicle electrical equipment 14 Power supply for auxiliary equipment 15 Relay 16 Relay 17 Resistance 18 ECU
19 Vehicle speed sensor 21 DCDC converter 22 Drive battery 23 Auxiliary battery 24 Capacitor

Claims (3)

An engine starter battery for supplying electric power to a cell motor for starting the engine, an auxiliary power source for supplying electric power to an in-vehicle electrical equipment, and the engine starter, which are installed in a hybrid vehicle including a travel motor and an engine. In a hybrid vehicle power supply device comprising a switch provided between a battery and the auxiliary power supply,
A resistor provided between the engine starting battery and the auxiliary power source, and connected in parallel to the switch;
A power source for a hybrid vehicle, comprising: a control unit that sets a vehicle speed at the time of starting the engine to be lower and suppresses power consumption of the in-vehicle electrical equipment as the SOC of the battery for starting the engine is lower apparatus. In the hybrid vehicle power supply device according to claim 1,
The control means suppresses power consumption of the EPS assist that is the in-vehicle electrical equipment when it is determined that the SOC of the engine starting battery is lower than a first predetermined value. . In the hybrid vehicle power supply device according to claim 2,
When the control means determines that the SOC of the engine starting battery is lower than a second predetermined value lower than the first predetermined value, the power consumption of the EPS assist, ABS, and ASC, which are the in-vehicle electrical equipment, is determined. A power supply device for a hybrid vehicle characterized by being suppressed.

Images