HYBRID VEHICLE

• US 20110093151A1
• Filed: 06/08/2009
• Published: 04/21/2011
• Est. Priority Date: 06/30/2008
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Kojima, Yasushi, Takagi, Kensuke, Kimata, Masatoshi
• Granted Patent: US 8,423,217 B2
• Time in Patent Office: Days
• US Class Current: 701/22
• CPC Class Codes: B60K 1/02 comprising more than one electric motor
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 53/20 characterised by converters located in the vehicle
• CPC Class Codes: B60L 58/13 Maintaining the SoC within a determined range
• 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 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 2510/0685 Engine crank angle
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2540/215 Selection or confirmation of options
• CPC Class Codes: B60W 2710/081 Speed
• CPC Class Codes: B60W 2710/083 Torque
• CPC Class Codes: B60W 30/182 Selecting between different operative modes, e.g. comfort and performance modes
• CPC Class Codes: B60W 50/082 Selecting or switching between different modes of propelling
• CPC Class Codes: B60W 50/085 Changing the parameters of the control units, e.g. changing limit values, working points by control input
• CPC Class Codes: Y02T 10/40 : Engine management systems
• 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 10/84 : Data processing systems or methods, management, administration
• CPC Class Codes: Y02T 90/12 : Electric charging stations
• CPC Class Codes: Y02T 90/14 : Plug-in electric vehicles

Abstract

A hybrid vehicle wherein such a situation that the residual capacity of a battery drops significantly below the lower limit of a reasonable range is avoided while fuel efficiency is enhanced. The hybrid vehicle, including an engine, a generator, a battery, and an electric motor for driving, is further provided with a converter for supplying the voltage of the battery that has been boosted to the electric motor, an eco-switch for selecting a first mode or a second mode in association with the boosting operation of the converter, and a hybrid ECU for changing the upper limit of the voltage boosted by the converter from a first upper limit in the first mode to a second upper limit lower than the first upper limit when the second mode is selected by the eco-switch, and changing the upper limit of the voltage boosted by the converter from the second upper limit to the first upper limit when the residual capacity of the battery drops below a threshold.

Claims

1. A hybrid vehicle comprising an engine, a generator capable of generating electric power from mechanical power received from the engine, a battery for storing the electric power generated by the generator, and an electric motor capable of outputting mechanical traction power from the electric power supplied from the battery and the generator, the hybrid vehicle further comprising:

a voltage converter for boosting a voltage of the battery and supplying the boosted voltage to the electric motor;

a selector for selecting a first mode or a second mode for the boosting operation of the voltage converter; and

a controller for switching an upper limit of voltage boosted by the voltage converter from a first upper limit in the first mode to a second upper limit which is lower than the first upper limit when the second mode is selected by the selector, and switching the upper limit of voltage boosted by the voltage converter from the second upper limit to the first upper limit when a state of charge (SOC) of the battery drops below a threshold.

2. The hybrid vehicle according to claim 1, wherein the controller switches the upper limit of voltage boosted by the voltage converter from the second upper limit to the first upper limit when a state in which a power requested to a vehicle by a user exceeds a maximum vehicle output power available in the second mode has continued for a predetermined time period.

3. The hybrid vehicle according to claim 1, wherein

when the second mode is selected by the selector, the controller performs, in addition to a control of switching the upper limit of voltage boosted by the voltage converter, at least one of controls of

changing an engine operating point;

lowering a frequency of a carrier wave which is used to generate an input voltage to the electric motor; and

operating an accessory including an air conditioner in a saveenergy mode,

when the state of charge (SOC) drops below a threshold, the controller performs a control to restore, among controls performed in the second mode, only the upper limit of voltage boosted by the voltage converter from the second upper limit to the first upper limit.

4. The hybrid vehicle according to claim 1, wherein

when the second mode is selected by the selector, the controller performs, in addition to a control of switching the upper limit of voltage boosted by the voltage converter, at least one of controls of

changing an engine operating point;

lowering a frequency of a carrier wave which is used to generate an input voltage to the electric motor; and

operating an accessory including an air conditioner in a saveenergy mode,

when the state of charge (SOC) drops below a threshold,

the controller performs a control to restore, among controls performed in the second mode, the upper limit of voltage boosted by the voltage converter from the second upper limit to the first upper limit; and

the controller finishes the control to change the engine operating point if the control to change the engine operating point has been performed.

5. The hybrid vehicle according to claim 1, wherein the hybrid vehicle further comprises a generator inverter and an electric motor inverter, both having a DC/AC converting function, and the inverters are connected to a common voltage converter.

6. The hybrid vehicle according to claim 2, wherein the hybrid vehicle further comprises a generator inverter and an electric motor inverter, both having a DC/AC converting function, and the inverters are connected to a common voltage converter.

7. The hybrid vehicle according to claim 3, wherein the hybrid vehicle further comprises a generator inverter and an electric motor inverter, both having a DC/AC converting function, and the inverters are connected to a common voltage converter.

8. The hybrid vehicle according to claim 4, wherein the hybrid vehicle further comprises a generator inverter and an electric motor inverter, both having a DC/AC converting function, and the inverters are connected to a common voltage converter.