Control device for hybrid vehicle

• US 10,160,442 B2
• Filed: 12/11/2015
• Issued: 12/25/2018
• Est. Priority Date: 12/19/2014
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Higashitani, Mitsuharu, Okamoto, Tsuyoshi, Ikemoto, Noriaki
• Primary Examiner(s): Patel, Shardul D
• Application Number:
  US15/518,889
• Publication Number:
  US 20170240162A1
• Time in Patent Office: 1,110 Days
• Field of Search: 701 22, 180 65245, 903930, 903 93
• CPC Class Codes: B60K 6/20 the prime-movers consisting of electric motors and internal combustion engines, e.g. HEVs
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• CPC Class Codes: B60L 1/02 to electric heating circuits
• CPC Class Codes: B60L 15/007 Physical arrangements or structures of drive train converters specially adapted for the propulsion motors of electric vehicles
• CPC Class Codes: B60L 15/2045 for optimising the use of energy
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: B60L 58/20 having different nominal voltages
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60W 10/30 including control of auxiliary equipment, e.g. air-conditioning compressors or oil pumps
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/13 in order to stay within battery power input or output limits; in order to prevent overcharging or battery depletion
• CPC Class Codes: B60W 2030/1809 Without torque flow between driveshaft and engine, e.g. with clutch disengaged or transmission in neutral
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2552/15 Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: B60W 2710/244 : Charge state
• CPC Class Codes: B60W 2710/305 : target power to auxiliaries
• CPC Class Codes: B60W 30/18072 : Coasting
• CPC Class Codes: B60W 50/0097 : Predicting future conditions
• CPC Class Codes: B60Y 2200/92 : Hybrid vehicles
• CPC Class Codes: Y02T 10/60 : Other road transportation technologies with climate change mitigation effect
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y02T 90/14 : Plug-in electric vehicles
• CPC Class Codes: Y10S 903/93 : Conjoint control of different elements

Abstract

For a hybrid vehicle including: an engine and a motor, each of which is mounted as a driving source; a generator driven by the engine; a high-voltage battery and a low-voltage battery, each of which can be charged and discharged; a converter connected between the high-voltage battery and the low-voltage battery; and an auxiliary load that consumes electric power supplied from the high-voltage battery via the converter or electric power supplied from the low-voltage battery, a control device includes a control unit that executes converter limit control that stops the converter or reduces output of the converter when a state of charge of the high-voltage battery is lower than or equal to a predetermined threshold.

Claims

1. A control device for a hybrid vehicle including:

an engine and a motor, each of which is mounted as a driving source;

a generator driven by the engine;

a high-voltage battery and a low-voltage battery, each of which is able to be charged and discharged;

a converter connected between the high-voltage battery and the low-voltage battery; and

an auxiliary load that consumes electric power supplied from the high-voltage battery via the converter or electric power supplied from the low-voltage battery, wherein the control device comprising;

a control unit that executes converter limit control that stops the converter or reduces output of the converter when a state of charge of the high-voltage battery is lower than or equal to a predetermined threshold, wherein

the control unit executes the converter limit control at a time of coasting drive on which the hybrid vehicle runs in a neutral state and the engine is stopped.

2. The control device according to claim 1, wherein the control unit executes the converter limit control when the state of charge of the high-voltage battery is lower than or equal to the threshold during execution of a power transmission interruption function by which power transmission between the driving source and a drive wheel is interrupted by the coasting drive.

3. The control device according to claim 1, wherein the control unit varies the converter limit control in accordance with a state of the low-voltage battery.

4. The control device according to claim 1, wherein the control unit varies the converter limit control in accordance with the state of charge of the high-voltage battery and a speed of the vehicle.

5. A control device for a hybrid vehicle including:

an engine and a motor, each of which is mounted as a driving source;

a generator driven by the engine;

a high-voltage battery and a low-voltage battery, each of which is able to be charged and discharged;

a converter connected between the high-voltage battery and the low-voltage battery; and

a plurality of auxiliary loads, each of which consumes electric power supplied from the high-voltage battery via the converter or electric power supplied from the low-voltage battery, wherein the control device comprising;

a control unit that executes auxiliary load limit control that stops at least one of the plurality of auxiliary loads or reduces electric power consumption of at least one of the plurality of auxiliary loads when a state of charge of the high-voltage battery is lower than or equal to a predetermined threshold, wherein

the control unit executes the auxiliary load limit control at a time of coasting drive on which the hybrid vehicle runs in a neutral state and the engine is stopped, and

the control unit executes the auxiliary load limit control during execution of a power transmission interruption function by which power transmission between the driving source and a drive wheel is interrupted by the coasting drive.

6. The control device according to claim 5, wherein the control unit varies the auxiliary load limit control in accordance with the state of charge of the high-voltage battery and a speed of the vehicle.

7. A control device for a hybrid vehicle including:

an engine and a motor, each of which is mounted as a driving source;

a generator driven by the engine;

a high-voltage battery and a low-voltage battery, each of which is able be charged and discharged;

a converter connected between the high-voltage battery and the low-voltage battery; and

an auxiliary load that consumes electric power supplied from the high-voltage battery via the converter or electric power supplied from the low-voltage battery, wherein the control device comprising;

a calculation unit that calculates predicted duration as well as a predicted lower limit reaching time during execution of a power transmission interruption function by which power transmission between the driving source and a drive wheel is interrupted by a coasting drive of the hybrid vehicle that runs in a neutral state, the predicted duration being a predicted value of time it takes for the execution of the power transmission interruption function to end, and the predicted lower limit reaching time being a predicted value of time it takes for a state of charge of the high-voltage battery to reach an allowable lower limit; and

a control unit that executes converter limit control that stops the converter or reduces output of the converter when the predicted duration is longer than the predicted lower limit reaching time, wherein

the control unit executes the converter limit control at a time of the coasting drive on which the hybrid vehicle runs in the neutral state and the engine is stopped.

9. The control device according to claim 7, wherein the calculation unit calculates the predicted duration, based on at least one of a speed of the vehicle, a road gradient, a constraint of a forward vehicle ahead the vehicle, and a constraint of a road environment.

10. The control device according to claim 7, wherein the calculation unit calculates the predicted lower limit reaching time, based on a past behavior of the state of charge of the high-voltage battery.

8. A control device for a hybrid vehicle including:

an engine and a motor, each of which is mounted as a driving source;

a generator driven by the engine;

a high-voltage battery and a low-voltage battery, each of which is able to be charged and discharged;

a converter connected between the high-voltage battery and the low-voltage battery; and

a plurality of auxiliary loads, each of which consumes electric power supplied from the high-voltage battery via the converter or electric power supplied from the low-voltage battery, wherein the control device comprising;

a calculation unit that calculates predicted duration as well as a predicted lower limit reaching time during execution of a power transmission interruption function by which power transmission between the driving source and a drive wheel is interrupted by a coasting drive of the hybrid vehicle that runs in a neutral state, the predicted duration being a predicted value of time it takes for the execution of the power transmission interruption function to end, and the predicted lower limit reaching time being a predicted value of time it takes for a state of charge of the high-voltage battery to reach an allowable lower limit; and

a control unit that executes auxiliary load limit control that stops at least one of the plurality of auxiliary loads or reduces electric power consumption of at least one of the plurality of auxiliary loads when the predicted duration is longer than the predicted lower limit reaching time, wherein

the control unit executes the auxiliary load limit control at a time of the coasting drive on which the hybrid vehicle runs in the neutral state and the engine is stopped.