Control Device for Hybrid Vehicle

• US 20100151987A1
• Filed: 03/28/2003
• Published: 06/17/2010
• Est. Priority Date: 03/29/2002
• Status: Abandoned Application

• Current Assignee: Nissan Diesel Motor Co., Ltd. (Isuzu Motors Limited), Nippon Zoki
• Original Assignee: Nippon Zoki
• Inventors: Notsu, Ikurou
• Application Number:
  US10/508,325
• Publication Number:
  US 20100151987A1
• Time in Patent Office: Days
• US Class Current: 477/3
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60K 6/543 the transmission being a continuously variable transmission
• CPC Class Codes: B60K 6/547 the transmission being a stepped gearing
• CPC Class Codes: B60L 2240/421 Speed
• 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 10/10 including control of change-speed gearings
• 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 2710/081 Speed
• 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 10/72 Electric energy management in electromobility

Abstract

There are provided an engine 1; a transmission 2 that transmits rotation of the engine 1 to drive wheels; a rotating electric machine 4; a reduction-ratio variator 6 transferring power by means of stepless speed change between the rotating electric machine 4 and the speed change transmission 2; an electric-storage element 12 storing electric power for supply to the rotating electric machine 4; and a control device for controlling the engine 1, the rotating electric machine 4 and the reduction-ratio variator 6 in accordance with operation conditions. The control device controls an output of the rotating electric machine 4 to provide the output required of the rotating electric machine 4 and also the rotational speed of the rotating electric machine 4 based on the optimum efficiency line of the rotating electric machine 4 so that the efficiency of the rotating electric machine 4 becomes optimal. The control device concurrently controls a reduction ratio of the reduction-ratio variator 6 in accordance with the vehicle speed at the time.

Claims

1. A control system for a hybrid vehicle with an engine and a rotating electric machine, comprising:

a transmission that is interposed between the engine and drive wheels of the vehicle;

a reduction-ratio variator that is interposed between the rotating electric machine and an input shaft of the transmission;

an electric-storage element that stores electric power for supply to the rotating electric machine, and

a control device for controlling an output of the engine and the rotating electric machine in accordance with vehicle operation conditions, and controlling a reduction ratio of the reduction-ratio variator, wherein;

the control device controls a torque and a rotational speed of the rotating electric machine on the basis of an output required of the rotating electric machine to obtain optimum values based on the optimum characteristics of efficiency of the rotating electric machine, and concurrently controls the reduction ratio of the reduction-ratio variator in accordance with a vehicle speed at the time.

2. The control system for a hybrid vehicle according to claim 1, wherein:

the reduction-ratio variator includes a continuously variable transmission.

3. The control system for a hybrid vehicle according to claim 1 or 2, wherein:

the control device controls the reduction ratio of the reduction-ratio variator to maximum when the vehicle starts and is accelerated.

4. The control system for a hybrid vehicle according to claim 1 or 2, wherein:

when the vehicle is decelerated, the control device allows the rotating electric machine to operate as a generator and controls the reduction ratio of the reduction-ratio variator to obtain a rotational speed of the rotating electric machine with high efficiency of electric-power generation.