System for driving hybrid vehicle, method thereof and electric power supply system therefor

• US 6,752,226 B2
• Filed: 04/02/2003
• Issued: 06/22/2004
• Est. Priority Date: 09/29/1998
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Katada, Hiroshi, Naito, Shotaro
• Primary Examiner(s): Johnson, Brian L.
• Assistant Examiner(s): Restifo, Jeffrey J
• Application Number:
  US10/404,107
• Publication Number:
  US 20030183430A1
• Time in Patent Office: 447 Days
• Field of Search: 180/65.2, 180/65.3, 180/65.1, 180/65.4, 180/65.8, 701/22, 318/139, 318/140, 323/266, 323/273, 323/275, 307/44, 307/10.1, 307/10.7, 320/103, 320/104, 320/145, 320/162
• US Class Current: 180/65.26
• CPC Class Codes: B60K 2006/268 Electric drive motor starts the engine, i.e. used as starter motor
• CPC Class Codes: B60K 6/485 Motor-assist type
• CPC Class Codes: B60K 6/54 Transmission for changing ratio
• CPC Class Codes: B60L 15/20 for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/12 Speed
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/445 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 3/0069 relating to the isolation, e.g. ground fault or leak current
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60W 10/04 including control of propulsion units
• 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 10/18 including control of braking systems
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• 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 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: B60W 2510/244 : Charge state
• CPC Class Codes: B60W 2520/10 : Longitudinal speed
• CPC Class Codes: B60W 2540/06 : Ignition switch
• CPC Class Codes: B60W 2540/10 : Accelerator pedal position
• CPC Class Codes: B60W 2552/15 : Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: F02D 41/20 : Output circuits, e.g. for controlling currents in command coils
• CPC Class Codes: F02N 11/04 : the motors being associated with current generators
• CPC Class Codes: F02N 11/0822 : related to action of the driver
• CPC Class Codes: F02N 11/0833 : Vehicle conditions F02N11/0822, F02N11/0825 take precedence
• CPC Class Codes: F02N 2200/023 : Engine temperature
• CPC Class Codes: F02N 2200/0801 : Vehicle speed
• CPC Class Codes: F02N 2200/101 : Accelerator pedal position
• CPC Class Codes: F02N 2200/124 : Information about road conditions, e.g. road inclination or surface
• 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 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y10S 903/917 : with transmission for changing gear ratio
• CPC Class Codes: Y10S 903/947 : Characterized by control of braking, e.g. blending of regeneration, friction braking

Abstract

A system for driving a hybrid vehicle having an engine, a motor/generator, a battery and a controller for the engine and the motor/generator. The controller has a plurality of operating modes. In an engine running electric generating mode, the engine is operated as a driving source of the vehicle and the motor/generator and electric power generated by the motor/generator is recovered to the battery when the charge ratio is low. In an acceleration mode, the engine and the motor/generator are operated as the driving source of the vehicle when the charge ratio of the battery is high, and the accelerator opening degree or a rate of change of the accelerator opening degree is large. In an engine running mode only the engine is operate as the driving source of the vehicle when the charge ratio of the battery is high and the accelerator opening degree is small.

Claims

1. A power source device for a hybrid vehicle comprising an engine;

a motor/generator coupled to said engine;

a battery connected to said motor/generator through an electric power converter; and

a control unit;

wherein;

said battery is constituted by a main battery and an auxiliary battery;

said control unit includes an engine controller for controlling said engine in response to an operating state of said hybrid vehicle and an M/G controller for controlling the motor/generator;

said main battery is controlled by a voltage that is equal to or less than 60 V and higher than a voltage of said auxiliary battery;

said main battery is a power source for driving said motor/generator, an injector of said engine and an intake/exhaust valve;

said main battery is a ground side connected in common with a ground side of said auxiliary battery;

said auxiliary battery is connected to said main battery through a switching element, and is controlled to a voltage of 12V or 24V; and

said control unit includes

a duty cycle calculation unit for calculating a duty cycle for charging said auxiliary battery based on an instruction voltage from said control unit that is predetermined in response to a charge ratio of said main battery and a voltage of said auxiliary battery,

a pulse width modulation control unit for generating a pulse width modulated signal corresponding to said duty cycle,

an auxiliary battery controller for controlling said switching element and charging said auxiliary battery from said main battery, and

an operation mode discriminating and processing unit having an engine running electric generating mode in which the battery is charged with the motor/generator being applied as an electrical power generator when the charge ratio of said main battery is less than a predetermined value, and having an engine running mode in which only said engine is operated when the charge ratio of said main battery exceeds a predetermined value and is less than a target torque.