JP2021187284A - Vehicle control device - Google Patents

Abstract

To provide a vehicle control device that can provide function of a system even when a failure occurs in a battery for auxiliary machinery.SOLUTION: A vehicle control device 1 includes: a DCDC converter 11; a switching device 14; a battery 12 for auxiliary machinery and a first controller 13 which are connected between the DCDC converter 11 and the switching device 14; and a battery 16 for auxiliary machinery and a second controller 17 which are connected to the DCDC converter 11 via the switching device 14. The first controller 13 has a function for starting up a vehicle.SELECTED DRAWING: Figure 1

Description

The present invention relates to a vehicle control device.

Conventionally, a system that realizes advanced driving support when an abnormality occurs in the main power supply has been known (Patent Document 1). The invention described in Patent Document 1 operates an electric load that realizes an advanced driver assistance system by supplying electric power from a sub power source when an abnormality occurs in the main power source.

Japanese Unexamined Patent Publication No. 2017-2180113

However, the invention described in Patent Document 1 does not consider the case where an abnormality occurs in the sub power supply (auxiliary battery).

The present invention has been made in view of the above problems, and an object of the present invention is to provide a vehicle control device capable of realizing the functions of the system even when an abnormality occurs in the auxiliary battery. ..

The vehicle control device according to one aspect of the present invention includes a DCDC converter, a switching device, a first auxiliary battery and a first controller connected between the DCDC converter and the switching device, and DCDC via the switching device. It includes a second auxiliary battery and a second controller connected to the converter. The first controller has a function of activating the vehicle.

According to the present invention, the function of the system can be realized even when an abnormality occurs in the auxiliary battery.

FIG. 1 is a block diagram of a vehicle control device 1 according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the drawings, the same parts are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 1, the vehicle control device 1 includes a drive battery 10, a DCDC converter 11, an auxiliary battery 12 (first auxiliary battery), a first controller 13, a switching device 14, and a relay. A 15 is provided, an auxiliary battery 16 (second auxiliary battery), and a second controller 17.

The vehicle control device 1 is mounted on a vehicle having an automatic driving function. The automatic driving in the present embodiment will be described as assuming that all the operations related to acceleration, steering, and deceleration are automatically performed regardless of the user's operation, but the present invention is not limited to this. In the automatic driving, at least two of the operations related to acceleration, steering, and deceleration may be automatically performed, and the remaining operations may be performed by the user. Alternatively, in automatic driving, at least one of the operations related to acceleration, steering, and deceleration may be automatically performed, and the remaining operations may be performed by the user.

The drive battery 10 is a drive battery mainly used as a power source for a motor (not shown). The drive battery 10 is a large-capacity secondary battery composed of a plurality of battery modules. The drive battery 10 may be referred to as a high-power battery.

A DCDC converter 11 is connected between the drive battery 10 and the switching device 14. The DCDC converter 11 steps down the power of the drive battery 10 to supply power to the auxiliary battery 12 and the auxiliary battery 16. The arrows in FIG. 1 indicate the direction in which power is supplied.

An auxiliary battery 12 and a first controller 13 are connected between the DCDC converter 11 and the switching device 14. The auxiliary battery 12 is used as a power source for electrical components mounted on the vehicle. The auxiliary battery 12 is a lead storage battery (LAB: Lead Acid Battery) that operates at a voltage of 12 V to 15 V. The electrical components to which the auxiliary battery 12 is supplied with electric power are, for example, a navigation device, an audio device, and the like. Further, the auxiliary battery 12 supplies electric power not only to the electrical components but also to the first controller 13.

The first controller 13 is a so-called ECU (Electronic Control Unit), and is an electronic control unit having a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. Various functions are realized by executing the software embedded in the first controller 13.

One of the functions is the function of starting the vehicle. Specifically, the first controller 13 has a function of activating the vehicle when it receives a signal transmitted from the intelligence key possessed by the user before the user gets on the vehicle. As an example, starting up here means making electrical components available. By activating the vehicle before the user gets on the vehicle, the user can use the navigation device, the audio device, and the like immediately after the ride. In addition, starting the vehicle using the signal transmitted from the intelligence key may be called AUTOACC.

The definition of activation is not limited to the above. Starting a vehicle may be defined as making the vehicle runnable. When the user presses the power switch while depressing the brake pedal, a predetermined signal is transmitted to the first controller 13. Upon receiving this signal, the first controller 13 puts the vehicle in a runnable state. The first controller 13 has a function of maintaining the activated state.

Another function is to control electrical components. Specifically, the first controller 13 has a function of controlling a navigation device, an audio device, and the like in response to user input.

Another function is an automatic driving function. Specifically, the first controller 13 has a function of controlling various actuators such as an accelerator actuator, a steering actuator, and a brake actuator by using information acquired by a camera or the like so as to automatically travel along a preset route. Has. As a result, automatic operation is realized. The first controller 13 may have at least one of a function of automatically accelerating and decelerating the vehicle and a function of automatically steering the vehicle.

Another function is an emergency stop function. Specifically, when the first controller 13 detects some abnormality, it has a function of setting a route different from the preset route and automatically stopping the vehicle on the shoulder or the like.

As shown in FIG. 1, the auxiliary battery 16 and the second controller 17 are connected to the DCDC converter 11 via the switching device 14. The auxiliary battery 16 is used as a power source for electrical components in the same manner as the auxiliary battery 12. The auxiliary battery 16 is the same as the auxiliary battery 12 in that it operates at a voltage of 12 V to 15 V, but the auxiliary battery 16 is not a lead storage battery but a lithium ion battery (LiB: Lithium-ion Battery). The auxiliary battery 16 supplies electric power not only to the electrical components but also to the second controller 17. The auxiliary battery 12 and the auxiliary battery 16 may be referred to as a light electric battery.

The second controller 17 is an electronic control unit like the first controller 13. In the present embodiment, the second controller 17 has few functions to be realized as compared with the first controller 13. In other words, the number of software embedded in the second controller 17 is smaller than the software incorporated in the first controller 13. As a function common to the second controller 17 and the first controller 13, both controllers have an emergency stop function. However, unlike the first controller 13, the second controller 17 does not have a function of activating the vehicle.

The auxiliary battery 12 and the first controller 13 are arranged on the upstream side of the auxiliary battery 16 and the second controller 17.

A relay 15 is connected between the switching device 14 and the auxiliary battery 16. The on / off of the relay 15 is controlled by an arbitrary controller. That is, the ECU that controls the on / off of the relay 15 may be the first controller 13, the second controller 17, or another ECU.

The switching device 14 incorporates an ECU different from that of the first controller 13 and the second controller 17, and this ECU monitors the voltage of the circuit on the downstream side when viewed from the DCDC converter 11 (hereinafter, simply referred to as circuit voltage). .. The circuit on the downstream side means a circuit arranged in a direction in which power is supplied from the DCDC converter 11. When an abnormality is detected in the circuit voltage on the downstream side, the switching device 14 switches its open / closed state from on to off to cut off the circuit. By this interruption, the auxiliary battery 16 and the second controller 17 are separated from the circuit on the downstream side. The case where an abnormality is detected in the circuit voltage on the downstream side means, for example, the case where the circuit voltage on the downstream side exceeds the threshold value. This threshold value may be set from the viewpoint of fail-safe.

Next, the conditions for turning the switching device 14 from off to on will be described. The switching device 14 is turned on when the voltages of the auxiliary battery 12 and the auxiliary battery 16 are equal. As a scene, for example, when the vehicle starts, the voltages of the auxiliary battery 12 and the auxiliary battery 16 gradually increase. Then, when the voltages of the auxiliary battery 12 and the auxiliary battery 16 become equal (for example, when both voltages reach the rated voltage), the switching device 14 is turned on. Here, "the voltages of the auxiliary battery 12 and the auxiliary battery 16 are equal" is not limited to exactly the same. "The voltage of the auxiliary battery 12 and the auxiliary battery 16 are equal" means that they are substantially the same (can be regarded as almost the same).

(Action effect)
It is difficult for the auxiliary battery 12 (lead-acid battery) to make a self-judgment as to whether or not an abnormality has occurred in itself. Therefore, in the present embodiment, the auxiliary battery 12 is arranged on the upstream side of the auxiliary battery 16, that is, between the DCDC converter 11 and the switching device 14. By arranging in this way, even if an abnormality occurs in the auxiliary battery 12, power is supplied to the first controller 13 from the DCDC converter 11. Therefore, even if an abnormality occurs in the auxiliary battery 12, the stoppage of the function of the first controller 13 is avoided. For example, it is prevented that the vehicle does not start. As described above, according to the present embodiment, even if an abnormality occurs in the auxiliary battery 12, the system stoppage is avoided.

Further, in the present embodiment, a redundant configuration is provided by configuring two auxiliary batteries. Furthermore, different types of batteries (lead-acid battery and lithium-ion battery) were used for the two auxiliary batteries. This increases the possibility of avoiding a situation in which an abnormality occurs in two auxiliary batteries at the same time.

Further, in the present embodiment, a redundant configuration is made by configuring two controllers having an emergency stop function. As a result, even if an abnormality occurs in either controller, the vehicle can be automatically stopped by the other controller, so that reliability in automatic driving is ensured.

Further, the first controller 13 has an emergency stop function (a function of automatically stopping the vehicle) in addition to the function of starting the vehicle. The second controller 17 also has this emergency stop function. The functions realized by the second controller 17 are designed to be less than the functions realized by the first controller 13. As a result, the power consumed by the second controller 17 is reduced, and the auxiliary battery 16 is more likely to last a long time. This is useful in the following cases. It is assumed that some abnormality occurs in the first controller 13 during the automatic operation and an abnormality is detected in the circuit voltage on the downstream side. In this case, the switching device 14 is switched from on to off, and the auxiliary battery 16 and the second controller 17 are disconnected from the circuit on the downstream side. Here, as described above, the second controller 17 has an emergency stop function, and the power consumed by the second controller 17 is small. Therefore, even if the auxiliary battery 16 and the second controller 17 are separated from the circuit on the downstream side during automatic operation, there is an increased possibility that the auxiliary battery 16 alone can cover the power consumed by the second controller 17. , The possibility that the vehicle can be stopped automatically increases.

Further, the switching device 14 switches its opening / closing state from off to on when the voltages of the auxiliary battery 12 and the auxiliary battery 16 are equal. This makes it possible to prevent the generation of inrush current when switching from off to on, and to suppress the magnitude of the inrush current.

As mentioned above, embodiments of the invention have been described, but the statements and drawings that form part of this disclosure should not be understood to limit the invention. This disclosure will reveal to those skilled in the art various alternative embodiments, examples and operational techniques.

1 Vehicle control device 10 Drive battery 11 DCDC converter 12, 16 Auxiliary battery 13 1st controller 14 Switching device 15 Relay 17 2nd controller

Claims (6)

A vehicle control device mounted on a vehicle.
DCDC converter and
Switching devices and
A first auxiliary battery and a first controller connected between the DCDC converter and the switching device.
A second auxiliary battery and a second controller connected to the DCDC converter via the switching device are provided.
The first controller is a vehicle control device having a function of activating the vehicle. The vehicle control device according to claim 1, wherein the first auxiliary battery is a lead storage battery. The vehicle control device according to claim 1 or 2, wherein the second auxiliary battery is a lithium ion battery. The first controller further has a function of automatically stopping the vehicle.
Any of claims 1 to 3, wherein the second controller has at least a function of automatically stopping the vehicle, while the function realized by the second controller is less than the function realized by the first controller. The vehicle controller according to claim 1. The vehicle control device according to claim 4, wherein the first controller has at least one of a function of automatically accelerating and decelerating the vehicle and a function of automatically steering the vehicle. One of claims 1 to 5, wherein the switching device switches its open / closed state from off to on when the voltages of the first auxiliary battery and the second auxiliary battery are equal to each other. The vehicle control device described in the section.

Images