Drive control system for hybrid vehicles

• US 6,201,312 B1
• Filed: 01/21/1999
• Issued: 03/13/2001
• Est. Priority Date: 02/17/1998
• Status: Expired due to Term

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Endo, Hiroatsu, Shioiri, Hiroyuki, Oba, Hidehiro, Hoshiya, Kazumi, Umeyama, Mitsuhiro
• Primary Examiner(s): Enad, Elvin
• Application Number:
  US09/234,376
• Time in Patent Office: 782 Days
• Field of Search: 290/40-A-
• US Class Current: 290/40.00C
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60K 6/54 Transmission for changing ratio
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• 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 20/15 Control strategies specially adapted for achieving a particular effect
• CPC Class Codes: B60W 2510/0623 Fuel flow rate
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2552/15 Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: Y02T 10/40 Engine management systems
• 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 10/84 Data processing systems or methods, management, administration
• CPC Class Codes: Y10S 903/903 having energy storing means, e.g. battery, capacitor
• CPC Class Codes: Y10S 903/91 Orbital, e.g. planetary gears
• CPC Class Codes: Y10S 903/917 with transmission for changing gear ratio
• CPC Class Codes: Y10S 903/946 Characterized by control of driveline clutch

Abstract

A control system for improving the fuel economy of a hybrid vehicle by evaluating a fuel to be consumed for a charging operation thereby to select a running mode. Specifically, a drive control system for a hybrid vehicle including an internal combustion engine, an electric motor and a battery device. The drive control system comprises: a first evaluator for evaluating the fuel consumption in the case assuming that the run with a demanded power is made by using the electric power reserved in the battery device, while including the fuel consumption at the time when the battery device is charged with the electric power; a second evaluator for evaluating the fuel consumption in the case assuming that the run with the demanded power is made by the motive power generated by burning the fuel in the internal combustion engine; and a motive power selector for selecting one of the run using the electric motor and the run using the internal combustion engine, on the basis of the evaluation results of the first evaluator and the second evaluator.

Claims

1. A drive control system for a hybrid vehicle, which can select a run using a motive power generated by burning a fuel in an internal combustion engine and a run using a motive power generated with an electric power by an electric motor and which can generate and reserve the electric power in a battery device, comprising:

first evaluation means for evaluating the fuel consumption in the case assuming that the run with a demanded power is made by using the electric power reserved in said battery device, while including the fuel consumption at the time when said battery device is charged with the electric power;

second evaluation means for evaluating the fuel consumption in the case assuming that said run with the demanded power is made by said motive power generated by burning the fuel in the internal combustion engine; and

motive power selecting means for selecting one of said run using the electric motor and said run using the internal combustion engine, on the basis of the evaluation results of said first evaluation means and said second evaluation means.

2. A drive control system for a hybrid vehicle according to claim 1,

wherein said first evaluation means includes means for determining a fuel amount per unit energy, from the fuel consumed for the charge and the energy amount charged in said battery device;

wherein said second evaluation means includes means for determining a fuel amount per unit energy outputted by said internal combustion engine; and

wherein said motive power selecting means includes means for comparing the fuel amount per unit energy, as determined by said first evaluation means, and the fuel amount per unit energy, as determined by said second evaluation means.

3. A drive control system for a hybrid vehicle according to claim 1,

wherein said first evaluation means includes means for determining a fuel amount per unit of the energy, with which said battery device is charged, on the basis of a plurality of data including the fuel consumption in a running state of the internal combustion engine when the run and the power generation are performed by said internal combustion engine.

4. A drive control system for a hybrid vehicle according to claim 1, further comprising:

means for determining said demanded power on the basis of at least one of a driver'"'"'s demanding power, as calculated on the basis of data including a vehicle speed and a throttle opening, a load on the vehicle, and a load for charging the battery.

5. A drive control system for a hybrid vehicle according to claim 1, further comprising:

means for calculating the fuel consumption at the time when said battery device is charged with said electric power, on the basis of a difference between the fuel consumption of a running point of said internal combustion engine when said charging operation is performed, and the fuel consumption at a running point of said internal combustion engine when it is assumed that said charging operation is not performed.

6. A drive control system for a hybrid vehicle according to claim 5, further comprising:

a transmission for changing the speeds of the motive power inputted from said internal combustion engine and the motive power inputted from said electric motor and for outputting the speeds; and

means for determining the fuel consumption at the individual running points on the basis of a plurality of data including the gear ratio set by said transmission.