Apparatus for recovering thermal energy from engine

• US 4,774,811 A
• Filed: 02/10/1987
• Issued: 10/04/1988
• Est. Priority Date: 02/10/1986
• Status: Expired due to Term

• Current Assignee: Hideo Kawamura
• Original Assignee: Isuzu Motors Limited
• Inventors: Kawamura, Hideo
• Primary Examiner(s): KOCZO JR, MICHAEL
• Application Number:
  US07/013,044
• Time in Patent Office: 602 Days
• Field of Search: 60/597, 60/607, 60/608, 180/65.2, 180/65.3, 180/65.4, 180/65.5, 180/65.6, 180/165, 290/52
• US Class Current: 60/608
• CPC Class Codes: B60K 6/24 characterised by the combustion engines
• CPC Class Codes: B60K 6/26 characterised by the motors or the generators
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60K 7/0007 the motor being electric
• CPC Class Codes: B60T 1/10 by utilising wheel movement for accumulating energy, e.g. driving air compressors
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60Y 2400/435 Supercharger or turbochargers
• CPC Class Codes: F02B 37/005 Exhaust driven pumps being combined with an exhaust driven auxiliary apparatus, e.g. a ventilator
• CPC Class Codes: F02B 37/04 Engines with exhaust drive and other drive of pumps, e.g. with exhaust-driven pump and mechanically-driven second pump
• CPC Class Codes: F02B 37/14 Control of the alternation between or the operation of exhaust drive and other drive of a pump, e.g. dependent on speed
• CPC Class Codes: F02B 39/10 electric
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y10S 903/905 Combustion engine
• CPC Class Codes: Y10S 903/906 Motor or generator

Abstract

An apparatus for recovering thermal energy from an engine of a motor vehicle has a first rotary electric machine coupled to a turbocharger mounted on the engine, a second rotary electric machine coupled to an exhaust turbine disposed in an exhaust system of the engine, and a third rotary electric machine mounted on an axle of the motor vehicle. The apparatus also includes respective means for detecting an engine rotational speed, an engine load, and an engine boost pressure. The first, second, and third rotary electric machines are controlled on the basis of signals from these means for effective utilization of the energy of an exhaust gas discharged from the engine.

Claims

1. An apparatus for recovering thermal energy from an engine mounted on a motor vehicle and having an exhaust system, comprising:

a turbocharger mounted on the engine and having a rotatable shaft;

an exhaust turbine having a rotatable shaft and disposed in the exhaust system;

a first rotary electric machine coupled to the rotatable shaft of said turbocharger;

a second rotary electric machine coupled to the rotatable shaft of said exhaust turbine;

at least one third rotary electric machine mounted on an axle of the motor vehicle;

a battery for storing electric power generated by said first, second, and third rotary electric machines;

means for detecting the rotational speed of the engine;

means for detecting the load on the engine;

means for detecting the boost pressure of the engine; and

a controller for controlling said first, second, and third rotary electric machines to operate as generators or motors according to the rotational speed, load, and boost pressure of the engine.

2. An apparatus according to claim 1, wherein said controller comprises means for controlling said first rotary electric machine to operate as a generator, means for controlling said second rotary electric machine to operate as a generator, and means for charging said battery with electric power generated by said first and second rotary electric machines, while the engine is idling.

3. An apparatus according to claim 2, wherein said means for controlling said first rotary machine to operate as a generator has means for controlling the generator load such that the turbine of said turbocharger will be operated with an optimum efficiency according to a relationship between the turbine speed and the adiabatic expansion rate.

4. An apparatus according to claim 1, wherein said controller comprises means for controlling said first and third rotary electric machines to operate as generators, means for controlling said second rotary electric machine to operate as a generator, and means for charging said battery with electric power generated by said first, second, and third rotary electric machines, while the motor vehicle is subjected to engine braking.

5. An apparatus according to claim 1, wherein said controller has means for controlling said first rotary electric machine to operate as a motor energized by electric power from said battery while the engine is subjected to a medium load.

6. An apparatus according to claim 5, wherein said means for controlling said first rotary electric machine to operate as a motor has means for controlling electric power supplied to said first rotary electric machine according to the boost pressure.

7. An apparatus according to claim 1, wherein said controller comprises means for controlling said first rotary electric machine to operate as a motor energized by electric power from said battery, means for controlling sid second rotary electric machine to operate as a generator, and means for controlling said third rotary electric machine to operate as a motor energized by electric power generated by said second rotary electric machine, while the engine is rotating at a low speed under a high load.

8. An apparatus according to claim 7, wherein said means for controlling said first rotary electric machine has means for supplying electric power to said first rotary electric machine according to the boost pressure.

9. An apparatus according to claim 1, wherein said controller has means for controlling said third rotary electric machine to operate as a motor energized by electric power generated by said second rotary electric machine when the boost pressure is higher than a prescribed value while the engine is rotating at a low speed under a high load.

10. An apparatus according to claim 1, wherein said controller has means for controlling the generator load of said second rotary electric machine when operating as a generator such that said exhaust turbine will be operated with an optimum efficiency.

11. An apparatus according to claim 1, wherein said controller comprises means for controlling said first rotary electric machine to operate as a generator, means for controlling said second rotary electric machine to operate as a generator, and means for controlling said third rotary electric machine to operate as a motor energized by electric power generated by said first and second rotary electric machines while the engine is being subjected to a low load.

12. An apparatus according to claim 11, wherein said means for controlling said first rotary electric machine to operate as a generator has means for controlling the generator load of said first rotary electric machine operating as a generator such that a turbine of said turbocharger will be operated with an optimum efficiency.

13. An apparatus according to claim 11, wherein said means for controlling said second rotary electric machine has means for controlling the generator load of said second rotary electric machine operating as a generator such that said exhaust turbine will be operated with an optimum efficiency.