JP2020167878A - Battery control device and battery control method - Google Patents

Abstract

To provide a battery control device and a battery control method, which can efficiently perform charge-discharge control while suppressing deterioration of a battery.SOLUTION: The battery control device is provided with: a calculation part; a prediction part and a determination part. The calculation part calculates the power storage residual amount of a storage battery which has a first range which is a predetermined ordinary power storage range, and a second range which is a power storage range other than the first range. The prediction part predicts a prediction charge-discharge amount in the current vehicle operation based on the learning result of a charge-discharge amount in the past vehicle operation. When a prediction power storage amount calculated based on the power storage residual amount and the prediction charge-discharge amount is out of the ordinary power storage range, the determination part determines a charge-discharge amount in the current vehicle operation based on a power storage range including the second range.SELECTED DRAWING: Figure 2

Description

The present invention relates to a battery control device and a battery control method.

Conventionally, for example, a hybrid vehicle including an engine which is a power source for traveling and an electric motor (so-called motor generator) which assists the operation of the engine is known. In such a hybrid vehicle, a battery control device that assists the operation of the engine by operating the electric motor as a generator during deceleration to charge the storage battery and supplying the electric power of the storage battery to the electric motor during acceleration is known. There is.

In this type of battery control device, there is a technique of predicting the amount of power consumption during traveling from map information or the like and giving priority to driving the electric motor if the amount of power consumption is sufficient (see, for example, Patent Document 1).

JP-A-2015-113075

However, in many cases, a charge / discharge prohibition range is set for the storage range of the storage battery from the viewpoint of battery protection, and a margin range is set between the normal range and the prohibition range as a fail-safe. In some cases.

Therefore, conventionally, since charging / discharging is performed within a normal range, it cannot be said that the storage battery is fully utilized, and there is room for improvement in efficient charge / discharging control.

The present invention has been made in view of the above, and an object of the present invention is to provide a battery control device and a battery control method capable of efficiently performing charge / discharge control while suppressing deterioration of the battery.

In order to solve the above-mentioned problems and achieve the object, the battery control device according to the present invention includes a calculation unit, a prediction unit, and a determination unit. The calculation unit calculates the remaining charge of a storage battery having a first range which is a predetermined normal storage range and a second range which is a storage range other than the first range. The prediction unit predicts the predicted charge / discharge amount in the current vehicle operation based on the learning result of the charge / discharge amount in the past vehicle operation. When the predicted storage amount calculated based on the remaining charge amount and the predicted charge / discharge amount deviates from the normal storage range, the determination unit charges / discharges in the current vehicle operation based on the storage range including the second range. Determine the amount.

According to the present invention, charge / discharge control can be efficiently performed while suppressing deterioration of the battery.

FIG. 1A is a block diagram showing a configuration of a control system according to an embodiment. FIG. 1B is a diagram showing an outline of a battery control method according to an embodiment. FIG. 2 is a block diagram showing a configuration of a battery control device according to an embodiment. FIG. 3 is a flowchart showing a processing procedure of processing executed by the battery control device according to the embodiment.

Hereinafter, embodiments of the battery control device and the battery control method disclosed in the present application will be described in detail with reference to the accompanying drawings. The present invention is not limited to this embodiment.

First, the outline of the battery control method according to the embodiment will be described with reference to FIGS. 1A and 1B. FIG. 1A is a block diagram showing a configuration of a control system according to an embodiment. FIG. 1B is a diagram showing an outline of a battery control method according to an embodiment.

The control system S shown in FIG. 1A is, for example, a control system mounted on a hybrid vehicle. The control system S includes a battery control device 1, an engine 11, a motor generator (MG) 12, a lithium ion battery (LiB) 13, a DCDC converter 14, a lead battery 15, and a load 16.

The engine 11 is a power source for traveling, and is an engine driven by other than electricity such as gasoline and hydrogen, for example. The MG 12 is driven by the electric power supplied from the LiB 13 during acceleration to assist the operation of the engine 11. Further, the MG 12 functions as a generator during deceleration to convert the kinetic energy associated with the deceleration into electrical energy and supply electric power to the LiB 13, the lead battery 15, and the load 16.

LiB13 is, for example, a 48V storage battery, and charges and discharges according to the control of the battery control device 1. Although the details will be described later in FIG. 1B, the battery control device 1 according to the embodiment performs charge / discharge control in consideration of the storage range for the margin set in LiB13.

The DCDC converter 14 steps down the power supplied from the MG 12 and the LiB 13 to supply the power to the lead battery 15 and the load 16. The lead battery 15 is, for example, a 12V storage battery, which supplies electric power to the load 16 and stores electric power supplied from MG 12 and LiB 13.

The load 16 is an electric device, and examples thereof include a navigation device, audio, and an air conditioner. Alternatively, the load 16 may be a vehicle control device that controls the vehicle, such as a PCS (Pre-crash Safety System) or an AEB (Advanced Emergency Braking System).

Here, the outline of the battery control method according to the embodiment will be described with reference to FIG. 1B. As shown in FIG. 1B, the storage range of LiB13 is the normal storage range (first range), the prohibited range (upper limit side and lower limit side), and the margin (second range) range (upper limit side and lower limit side). Side) and is often set.

Conventionally, by performing charge / discharge control within the normal storage range, even if there is an error in calculating the remaining charge, the charge / discharge is prevented from being charged / discharged to the range of prohibition of use within the range of the margin. For example, in FIG. 1B, when the MG is required to have "A" as the required torque, the MG is instructed to the actual torque "B + Y" corresponding to the remaining charge remaining in the normal storage range. Therefore, in the past, since charging / discharging is normally performed within the storage range, it cannot be said that LiB is fully utilized, and there is room for improvement in efficient charging / discharging control.

Therefore, in the battery control method according to the embodiment, it is decided to use the range of the margin for charge / discharge control by predicting the charge / discharge amount from the past running.

Specifically, as shown in FIG. 1B, first, in the battery control method according to the embodiment, the remaining charge amount of LiB13 having a predetermined normal storage range excluding the margin is calculated (S1). Specifically, the remaining storage amount is calculated with the upper limit of the normal storage range being 100% and the lower limit being 0%.

Subsequently, in the battery control method according to the embodiment, the predicted charge / discharge amount in the current vehicle operation is predicted based on the learning result of the charge / discharge amount in the past vehicle operation (S2). In the example shown in FIG. 1B, a case where the predicted discharge amount is predicted is shown.

Then, in the battery control method according to the embodiment, when the predicted storage amount calculated based on the remaining storage amount and the predicted charging / discharging amount deviates from the normal storage range, the charging in the current vehicle operation is based on the storage range including the margin. The amount of discharge is determined (S3).

Specifically, in the battery control method according to the embodiment, when "A" is requested as the required torque from MG12, the actual torque "B + Y" corresponding to the remaining storage amount in the normal storage range is combined with the margin on the lower limit side. Instruct MG12 with "B + Y + Z" to which the actual torque "Z" corresponding to the electric energy of is added.

As described above, in the battery control method according to the embodiment, by using the electric energy for the margin, charge / discharge control can be performed more efficiently than in the conventional case.

Further, in the battery control method according to the embodiment, by predicting the predicted charge / discharge amount based on the learning result of the past vehicle operation, it is possible to prevent the battery from being charged / discharged to the range of prohibition of use. That is, according to the battery control method according to the embodiment, charge / discharge control can be efficiently performed while suppressing deterioration of the battery.

Although the case where the battery control method according to the embodiment is applied to the discharge control of LiB13 is described in FIG. 1B, the battery control method according to the embodiment can also be applied to the charge control of LiB13.

Next, the configuration of the battery control device 1 according to the embodiment will be described in detail with reference to FIG. FIG. 2 is a block diagram showing the configuration of the battery control device 1 according to the embodiment. As shown in FIG. 2, the battery control device 1 according to the embodiment is connected to various sensors 100, LiB13 and MG12.

The various sensors 100 are sensors mounted on the vehicle, detect information about the vehicle, and output the detection result to the battery control device 1. The various sensors 100 include sensors that detect information related to vehicle operation, such as a camera, a position information detection device, a vehicle speed sensor, an acceleration sensor, a gyro sensor, and a radar.

The battery control device 1 according to the embodiment includes a control unit 2 and a storage unit 3. The control unit 2 includes a calculation unit 20, a learning unit 21, a prediction unit 22, and a determination unit 23. The storage unit 3 stores the learning information 30.

Here, the battery control device 1 includes, for example, a computer having a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a data flash, an input / output port, and various circuits.

The CPU of the computer functions as a calculation unit 20, a learning unit 21, a prediction unit 22, and a determination unit 23 of the control unit 2, for example, by reading and executing a program stored in the ROM.

Further, at least one or all of the calculation unit 20, the learning unit 21, the prediction unit 22, and the determination unit 23 of the control unit 2 are used by hardware such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array). It can also be configured.

Further, the storage unit 3 corresponds to, for example, a RAM or a data flash. The RAM or data flash can store learning information 30, information on various programs, and the like. The battery control device 1 may acquire the above-mentioned program and various information via another computer or a portable recording medium connected by a wired or wireless network.

The learning information 30 is information generated as a learning result of the learning unit 21 described later. The learning information 30 includes, for example, information indicating the relationship between the past vehicle operation and the charge / discharge amount.

The control unit 2 calculates the remaining charge and discharge amount of LiB13, predicts the predicted charge and discharge amount, and determines the charge and discharge amount in the current vehicle operation based on the remaining charge and discharge amount and the predicted charge / discharge amount.

The calculation unit 20 calculates the remaining charge of LiB13 having a predetermined normal charge range excluding the margin. Specifically, the calculation unit 20 calculates the SOC (State Of Charge) indicating the remaining charge by detecting the current value and the voltage value of the LiB13.

More specifically, the calculation unit 20 calculates the SOC based on the map information indicating the relationship between the current value (or voltage value) and the SOC. The calculation unit 20 outputs the calculated remaining charge information to the determination unit 23.

The calculation process of the remaining charge amount by the calculation unit 20 may be performed at regular intervals, for example, or may be performed at the timing of charging / discharging the LiB13 (for example, the timing of acceleration or deceleration).

The learning unit 21 learns the amount of charge / discharge in the past vehicle operation, and stores it in the storage unit 3 as learning information 30 indicating the learning result. Specifically, the learning unit 21 associates, for example, the amount of discharge, which is the amount of electric power supplied from the LiB13 to the MG12 during acceleration, with acceleration information (acceleration, vehicle speed, road gradient, etc.) regarding the situation during acceleration. It is stored as learning information 30.

More specifically, the learning unit 21 learns the amount of electric power in the supply continuation period from the start to the end of the electric power supply at the time of acceleration as the discharge amount. For example, when the accelerator is momentarily released during acceleration and the power supply is temporarily stopped, the learning unit 21 learns the sum of the power amounts before and after the power supply is stopped as the discharge amount. .. In other words, when the power supply stop period exceeds a predetermined period, the learning unit 21 ends the supply continuation period and learns the discharge amount.

Further, for example, the learning unit 21 associates the charge amount, which is the amount of electric power supplied from the MG 12 to the LiB 13 during deceleration, with the deceleration information (acceleration, vehicle speed, road gradient, etc.) regarding the situation during deceleration, and the learning information 30. Remember as.

Further, the learning unit 21 may store the characteristic information indicating the battery characteristics of the LiB 13 as the learning information 30 in association with the charge / discharge amount. Specifically, the characteristic information may include information such as the battery temperature of LiB13, the outside air temperature, the number of charge / discharge cycles (total number), the battery replacement date, and the charge / discharge frequency. The charge / discharge frequency refers to the number of charges / discharges in a certain period.

The learning unit 21 may generate, for example, a model that outputs a score indicating the predicted charge / discharge amount as a learning result. Specifically, the learning unit 21 uses machine learning in which the charge / discharge amount in the past vehicle operation is used as teacher data and the operation information (acceleration information, deceleration information, etc.) and characteristic information indicating the past vehicle operation are used as the elemental data. , A model that outputs a score indicating the predicted charge / discharge amount may be generated and stored as learning information 30.

The prediction unit 22 predicts the predicted charge / discharge amount in the current vehicle operation based on the learning result of the charge / discharge amount in the past vehicle operation. Specifically, the prediction unit 22 predicts the predicted charge / discharge amount based on the learning information 30 stored in the storage unit 3 at the timing when the vehicle motion (acceleration or deceleration) this time is detected.

For example, the prediction unit 22 predicts the predicted discharge amount in the current vehicle operation based on the learning result of the discharge amount in the past vehicle operation. Specifically, when the vehicle acceleration motion (accelerator depression or vehicle speed change is equal to or higher than a predetermined value) is detected, the prediction unit 22 determines the predicted discharge amount based on the acceleration motion information and the learning information 30. Predict.

Further, for example, the prediction unit 22 predicts the predicted charge amount in the current vehicle operation based on the learning result of the charge amount in the past vehicle operation. Specifically, when a vehicle deceleration operation (accelerator release or vehicle speed change is equal to or greater than a predetermined value) is detected, the prediction unit 22 determines the predicted charge amount based on the deceleration operation information and the learning information 30. Predict.

For example, the prediction unit 22 predicts a representative value calculated based on the charge / discharge amount in the past vehicle operation included in the learning information 30 as the predicted charge / discharge amount.

The representative value may be, for example, the average value of the charge / discharge amount in the past predetermined period, the maximum value, or the like. In this way, by using the representative value calculated from the past charge / discharge amount, the prediction accuracy of the predicted discharge amount can be improved.

Further, the prediction unit 22 may predict the predicted charge / discharge amount based on the learning result of the battery characteristics of LiB13 in the past vehicle operation included in the learning information 30. As a result, the prediction accuracy of the predicted discharge amount can be further improved.

The prediction unit 22 may add road information related to the traveling road when predicting the predicted charge / discharge amount. Road information includes, for example, fixed information (static information) such as road position, distance, and slope, and dynamic information such as traffic volume at the time of driving, weather, and road surface condition. Good.

The determination unit 23 determines the charge / discharge amount in the current vehicle operation based on the remaining charge amount calculated by the calculation unit 20 and the predicted charge / discharge amount predicted by the prediction unit 22.

Specifically, when the predicted storage amount calculated based on the remaining storage amount and the predicted charging / discharging amount deviates from the normal storage range, the determination unit 23 charges / discharges in the current vehicle operation based on the storage range including the margin. Determine the amount.

For example, when the predicted storage amount obtained by subtracting the predicted discharge amount from the remaining storage amount is less than the normal storage range, the determination unit 23 determines the discharge amount in the current vehicle operation based on the storage range including the margin on the lower limit side. To do. As a result, the amount of electric power including the margin can be supplied to the MG 12, so that the torque output by the MG 12 can be improved. That is, since the amount of electric power at the time of discharge can be increased, discharge control can be performed efficiently.

Further, for example, when the predicted storage amount obtained by adding the predicted discharge amount to the remaining storage amount exceeds the normal storage range, the determination unit 23 determines the charge amount in the current vehicle operation based on the storage range including the margin on the upper limit side. To determine. As a result, the amount of electric power including the margin can be charged to the LiB13, so that the electric power generated by the MG 12 can be stored without waste. That is, since the amount of electric power at the time of charging can be increased, charging control can be performed efficiently.

When the predicted storage amount is within the normal storage range, the determination unit 23 determines the charge / discharge amount based on the current storage amount, that is, based on the normal storage range.

Then, the determination unit 23 calculates the actual torque to be output by the MG 12 based on the determined charge / discharge amount, and outputs information indicating the actual torque to the MG 12.

Next, the processing procedure of the processing executed by the battery control device 1 according to the embodiment will be described with reference to FIG. FIG. 3 is a flowchart showing a processing procedure of processing executed by the battery control device 1 according to the embodiment.

As shown in FIG. 3, first, the calculation unit 20 calculates the remaining charge of LiB13 having a predetermined normal charge range excluding the margin (S101).

Subsequently, the prediction unit 22 predicts the predicted charge / discharge amount in the current vehicle operation based on the learning result of the charge / discharge amount in the past vehicle operation (S102).

Subsequently, the determination unit 23 calculates the predicted remaining charge amount based on the remaining amount of electricity stored and the predicted amount of charged / discharged charge (S103).

Subsequently, the determination unit 23 determines whether or not the calculated predicted remaining amount of electricity is out of the normal electricity storage range (S104).

Subsequently, the determination unit 23 determines the charge / discharge amount based on the storage range including the margin when the predicted storage amount deviates from the normal storage range (S104: Yes), and ends the process.

On the other hand, when the predicted charge / discharge amount is within the range of the normal storage range (S104: No), the determination unit 23 determines the charge / discharge amount based on the predicted charge / discharge amount, that is, the normal storage range (S106). , End the process.

As described above, the battery control device 1 according to the embodiment includes a calculation unit 20, a prediction unit 22, and a determination unit 23. The calculation unit 20 calculates the remaining storage amount of LiB13 having a first range which is a predetermined normal storage range and a second range which is a storage range other than the first range. The prediction unit 22 predicts the predicted charge / discharge amount in the current vehicle operation based on the learning result of the charge / discharge amount in the past vehicle operation. When the predicted storage amount calculated based on the remaining storage amount and the predicted charging / discharging amount deviates from the normal storage range, the determination unit 23 determines the charging / discharging amount in the current vehicle operation based on the storage range including the second range. .. As a result, charge / discharge control can be efficiently performed while suppressing deterioration of the battery.

Further effects and variations can be easily derived by those skilled in the art. For this reason, the broader aspects of the invention are not limited to the particular details and representative embodiments expressed and described as described above. Therefore, various modifications can be made without departing from the spirit or scope of the general concept of the invention as defined by the appended claims and their equivalents.

1 Battery control device 2 Control unit 3 Storage unit 11 Engine 12 Motor generator 13 Lithium-ion battery 14 DCDC converter 15 Lead battery 16 Load 20 Calculation unit 21 Learning unit 22 Prediction unit 23 Decision unit 30 Learning information 100 Various sensors S control system

Claims (6)

A calculation unit for calculating the remaining storage amount in the first range of a storage battery having a first range which is a predetermined normal storage range and a second range which is a storage range other than the first range.
Based on the learning result of the charge / discharge amount in the past vehicle operation, the prediction unit that predicts the predicted charge / discharge amount in the current vehicle operation,
When the predicted storage amount calculated based on the remaining charge and the predicted charge / discharge amount deviates from the normal storage range, the determination to determine the charge / discharge amount in the current vehicle operation based on the storage range including the second range. A battery control device characterized by having a unit. The prediction unit
Based on the learning result of the discharge amount in the past vehicle operation, the predicted discharge amount in the current vehicle operation is predicted,
The decision unit
When the predicted storage amount obtained by subtracting the predicted discharge amount from the remaining storage amount is lower than the normal storage range, the discharge amount in the current vehicle operation is determined based on the storage range including the second range on the lower limit side. The battery control device according to claim 1. The prediction unit
Based on the learning result of the charge amount in the past vehicle operation, the predicted charge amount in the current vehicle operation is predicted,
The decision unit
When the predicted storage amount obtained by adding the predicted charge amount to the remaining charge exceeds the normal storage range, the charge amount in the current vehicle operation is determined based on the storage range including the second range on the upper limit side. The battery control device according to claim 1 or 2. The prediction unit
The battery control device according to any one of claims 1 to 3, wherein a representative value calculated based on the charge / discharge amount in the past vehicle operation is predicted as the predicted charge / discharge amount. The prediction unit
The battery control device according to any one of claims 1 to 4, wherein the predicted charge / discharge amount is predicted based on the learning result of the battery characteristics of the storage battery in the past vehicle operation. A calculation step for calculating the remaining storage amount in the first range of a storage battery having a first range which is a predetermined normal storage range and a second range which is a storage range other than the first range.
Based on the learning result of the charge / discharge amount in the past vehicle operation, the prediction process for predicting the predicted charge / discharge amount in the current vehicle operation, and
When the predicted storage amount calculated based on the remaining storage amount and the predicted charging / discharging amount deviates from the normal storage range, the determination to determine the charging / discharging amount in the current vehicle operation based on the storage range including the second range. A battery control method characterized by including steps.