# US 11,444,478 B2 · Control device

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- Number: US 11,444,478 B2
- Document ID: US11444478B2
- Status: Granted
- Kind: B2
- Application number: 16/985,319
- Filed: 2020-08-05
- Published: 2021-02-25
- Granted: 2022-09-13
- Earliest claimed: 2019-08-21
- Assignees: Toyota Jidosha Kabushiki Kaisha
- Applicants: Toyota Jidosha Kabushiki Kaisha
- Inventors: Takayuki Akaishi
- Web page: https://patentgrep.com/patent/US11444478B2

## CPC

- H02J 7/96: in response to battery voltage
- B60L 3/12: Recording operating variables {; Monitoring of operating variables}
- B60L 50/15: with additional electric power supply (with capacitors charged by engine-driven generators B60L50/40; with batteries charged by engine-driven generators B60L50/61)
- B60L 58/12: responding to state of charge [SoC]
- B60L 58/13: Maintaining the SoC within a determined range
- G01R 31/367: Software therefor, e.g. for battery testing using modelling or look-up tables
- G01R 31/3835: involving only voltage measurements
- H02J 7/82: Control of state of charge [SOC]
- B60L 2210/10: DC to DC converters
- B60L 2240/547: Voltage
- B60L 2240/549: Current
- Y02T 10/7072: Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
- Y02T 10/92: Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles
- Y02T 90/14: Plug-in electric vehicles
- H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- B60L: PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES (arrangements or mounting of electrical propulsion units or of plural diverse prime-movers for mutual or common propulsion in vehicles B60K1/00, B60K6/20; arrangements or mounting of electrical gearing in vehicles B60K17/12, B60K17/14; preventing wheel slip by reducing power in rail vehicles B61C15/08; dynamo-electric machines H02K; control or regulation of electric motors H02P); SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES (electric coupling devices combined with mechanical couplings of vehicles B60D1/64; electric heating for vehicles B60H1/00); ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL (control or regulation of electric motors H02P); MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12)
- Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION

## Abstract

A control device includes: a voltage control unit that sequentially switches a command voltage of a direct current-direct current converter between different predetermined measurement voltages to control the command voltage; an obtaining unit that obtains, for each of the measurement voltages, a first terminal voltage of a battery when constant current discharge is performed and a second terminal voltage of the battery when constant current charge is performed; and a correction unit that corrects an SOV-OCV characteristic curve indicating a relationship between the state of charge and an open circuit voltage of the battery, based on a comparison between the first terminal voltages newly obtained by the obtaining unit and the first terminal voltages immediately previously obtained by the obtaining unit and a comparison between the second terminal voltages newly obtained by the obtaining unit and the second terminal voltages immediately previously obtained by the obtaining unit.

## Claims

### Claim 1

A control device comprising a processor configured to:
sequentially switch a command voltage of a direct current-direct current converter between a plurality of different predetermined measurement voltages to control the command voltage, the direct current-direct current converter being configured to control a state of charge of a battery;
obtain, for each of the measurement voltages that are switched, a first terminal voltage of the battery when constant current discharge is performed and a second terminal voltage of the battery when constant current charge is performed; and
correct a state of charge versus open circuit voltage characteristic curve indicating a relationship between the state of charge and an open circuit voltage of the battery, based on a comparison between a plurality of the first terminal voltages that are newly obtained and a plurality of the first terminal voltages that have been immediately previously obtained and a comparison between a plurality of the second terminal voltages that are newly obtained and a plurality of the second terminal voltages that have been immediately previously obtained.

### Claim 2 (depends on 1)

The control device according to claim 1, wherein the state of charge versus open circuit voltage characteristic curve of the battery has a flat region in which a rate of change in the open circuit voltage with respect to the state of charge is equal to or less than a predetermined value, and the processor is configured to switch the command voltage to a first voltage for controlling the state of charge of the battery to a state of charge at a boundary between the flat region and a region other than the flat region, the first voltage being one of the measurement voltages of the direct current-direct current converter.

### Claim 3 (depends on 2)

The control device according to claim 2, wherein the processor is configured to switch the command voltage between the first voltage, a second voltage higher than the first voltage by a predetermined value, and a third voltage lower than the first voltage by a predetermined value, the first, second, and third voltages being the measurement voltages of the direct current-direct current converter.

### Claim 4 (depends on 1)

The control device according to claim 1, wherein the processor is configured such that when there is a predetermined difference between at least one of the first terminal voltages that are newly obtained and a corresponding one of the first terminal voltages that have been immediately previously obtained, the processor corrects the state of charge versus open circuit voltage characteristic curve based on an amount of the difference.

### Claim 5 (depends on 1)

The control device according to claim 1, wherein the processor is configured such that when there is a predetermined difference between at least one of the second terminal voltages that are newly obtained and a corresponding one of the second terminal voltages that have been immediately previously obtained, the processor corrects the state of charge versus open circuit voltage characteristic curve based on an amount of the difference.

### Claim 6 (depends on 4)

The control device according to claim 4, further comprising a notification device configured to provide a predetermined notification indicating an abnormality of the battery when there is the difference only one of between the at least one of the first terminal voltages that are newly obtained and the corresponding one of the first terminal voltages that have been immediately previously obtained and between the at least one of the second terminal voltages that are newly obtained and the corresponding one of the second terminal voltages that have been immediately previously obtained.

### Claim 7 (depends on 1)

The control device according to claim 1, wherein the processor is configured to:
derive an open circuit voltage corresponding to a target state of charge based on a result of correction of the state of charge versus open circuit voltage characteristic curve;
update the command voltage of the direct current-direct current converter based on the open circuit voltage; and
control charge and discharge of the battery using the command voltage.