Apparatus for storing energy generated during breaking of a vehicle and for providing energy to the internal combustion engine of the vehicle at other times

• US 5,552,681 A
• Filed: 05/18/1995
• Issued: 09/03/1996
• Est. Priority Date: 03/06/1992
• Status: Expired due to Term

• Current Assignee: HINO Jidosha Kogyo Kabushiki Kaisha
• Original Assignee: HINO Jidosha Kogyo Kabushiki Kaisha
• Inventors: Suzuki, Takayuki, Obata, Atsuomi
• Primary Examiner(s): SALATA, ANTHONY J
• Application Number:
  US08/443,756
• Time in Patent Office: 474 Days
• Field of Search: 318/798-815, 318/139, 318/375, 318/254,376, 318/140, 318/148, 318/152, 318/798-815, 307/52, 307/54, 307/58, 307/63-68, 290/8, 290/14, 290/16, 290/20, 290/31, 290/34, 290/45, 290/50, 290/51, 363/34, 363/129, 363/131, 363/132, 363/150, 180/65.2, 180/65.4
• US Class Current: 318/139
• 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: B60L 2220/12 Induction machines
• CPC Class Codes: B60L 50/15 with additional electric power supply with capacitors charged by engine-driven generators B60L50/40; with batteries charged by engine-driven generators B60L50/61
• CPC Class Codes: B60L 50/40 using propulsion power supplied by capacitors
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 7/10 Dynamic electric regenerative braking B60L7/22 takes precedence
• CPC Class Codes: F02N 11/04 the motors being associated with current generators
• CPC Class Codes: F02N 11/0866 comprising several power sources, e.g. battery and capacitor or two batteries
• CPC Class Codes: F02N 2011/0888 DC/DC converters
• CPC Class Codes: F02N 2011/0896 Inverters for electric machines, e.g. starter-generators
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• 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

Abstract

A braking and auxiliary driving unit for an internal combustion engine which produces braking and auxiliary motive power by converting electrical energy in both directions between a polyphase AC circuit of a squirrel-cage polyphase induction machine linked to the rotary shaft of the internal combustion engine and the DC circuit of an electricity storage means, the electricity storage means comprises an electrostatic capacitive circuit. A low-voltage storage battery is provided in addition to this electrostatic capacitive circuit, and this can be coupled to the electrostatic capacitive circuit by a bidirectional DC-to-DC converter.

Claims

1. Braking and auxiliary drive apparatus for an internal combustion engine in a motor vehicle, comprising:

a squirrel-cage polyphase induction machine having a polyphase AC circuit, for coupling]said squirrel-cage polyphase induction machine being operatively coupled to a rotary shaft of an internal combustion engine;

an inverter circuit operatively coupled to said polyphase AC circuit of said squirrel-cage polyphase induction machine;

an electricity storage means comprising an electrostatic capacitive circuit operatively coupled to said inverter so that said inverter couples said electrostatic capacitive circuit to said polyphase AC circuit by converting electrical energy in both directions therebetween;

a step-up/step-down converter operatively coupled to said electrostatic capacitive circuit;

a rotation sensor that detects a rotational speed of said rotary shaft;

a storage battery operatively coupled to said step-up/step-down converter so that said step-up/step-down converter electrically connects said storage battery to said electrostatic capacitive circuit, said storage battery having a lower terminal voltage than a DC terminal voltage of said inverter circuit; and

a control circuit for controlling said inverter circuit, said control circuit operating in the following control modes;

an initial charging mode wherein said electrostatic capacitive circuit is charged with energy from said storage battery through said step-up/step-down converter, if said internal combustion engine is at a standstill;

a starting mode wherein energy stored in said electrostatic capacitive circuit is provided to said squirrel-cage polyphase induction machine as an AC current via said inverter circuit so that said squirrel-cage polyphase induction machine operates as an electric motor, if said internal combustion engine is being started;

a deceleration mode wherein said squirrel-cage polyphase induction machine operates an electric generator by supplying an AC signal having a frequency that is lower than a frequency corresponding to an actual speed detected by said rotational sensor, said AC signal being provided to said electrostatic capacitive circuit via said inverter circuit for charging said electrostatic capacitive circuit, if said vehicle is being braked; and

an acceleration mode wherein said squirrel-cage polyphase induction machine operates an electric motor by supplying an AC signal having a higher frequency than a frequency corresponding to an actual speed detected by said rotational sensor, said electrostatic capacitive circuit providing energy to said squirrel-cage polyphase induction machine via said inverter circuit, if said vehicle is being accelerated.

4. A braking and auxiliary driving means for a motor vehicle as set forth in claim 1, 2 or 3, and wherein a terminal voltage of said storage battery corresponds to a rated voltage of standard electric equipment of said motor vehicle.

9. In respect of a braking and auxiliary driving means for an internal combustion engine as set forth in claim 1:

a braking and auxiliary driving means for a motor vehicle characterised in that the control modes of the aforementioned control circuit include;

an initial charging mode wherein, with the aforementioned internal combustion engine at standstill, the aforementioned electrostatic capacitive circuit is charged with the energy of the aforementioned storage battery after the voltage has been stepped up by a step-up/step-down converter;

a starting mode wherein, when the aforementioned internal combustion engine is being started, energy stored in the aforementioned electrostatic capacitive circuit is given to the aforementioned squirrel-cage polyphase induction machine as an AC current via the aforementioned inverter circuit, and the aforementioned squirrel-cage polyphase induction machine is made to operate as an electric motor;

a deceleration mode wherein, when the aforementioned motor vehicle is being braked, the aforementioned squirrel-cage polyphase induction machine is made to operate as an electric generator, and the output AC current of the aforementioned squirrel-cage polyphase induction machine is supplied to the aforementioned electrostatic capacitive circuit as a charging current via the aforementioned inverter circuit; and

an acceleration mode, wherein, when the aforementioned motor vehicle is being accelerated, the aforementioned squirrel-cage polyphase induction machine is made to operate as an electric motor, and energy stored in the aforementioned electrostatic capacitive circuit is supplied via the aforementioned inverter circuit to the aforementioned squirrel-cage polyphase induction machine as an AC current.

11. A braking and auxiliary driving means for a motor vehicle as set forth in claim 1 or 10, and wherein:

said control modes of said control circuit also include;

a warm-up mode wherein, if internal combustion engine is warming up, said squirrel-cage polyphase induction machine operates as an electric generator and an output AC current of said squirrel-cage polyphase induction machine is supplied via said inverter circuit to said electrostatic capacitive circuit as a charging current; and

a supplementary charging mode wherein, if said internal combustion engine is operating and a terminal voltage of said electrostatic capacitive circuit no greater than a prescribed value, said squirrel-cage polyphase induction machine operates as an electric generator, and said output AC current of said squirrel-cage polyphase induction machine is supplied via said inverter circuit to said electrostatic capacitive circuit as a charging current.

2. Braking and auxiliary drive apparatus for an internal combustion engine in a motor vehicle, comprising:

a squirrel-cage polyphase induction machine having a polyphase AC circuit, for coupling]said squirrel-cage polyphase induction machine being operatively coupled to a rotary shaft of an internal combustion engine;

an inverter circuit operatively coupled to said polyphase AC circuit of said squirrel-cage polyphase induction machine;

an electricity storage means comprising an electrostatic capacitive circuit operatively coupled to said inverter so that said inverter couples said electrostatic capacitive circuit to said polyphase AC circuit by converting electrical energy in both directions therebetween;

a bidirectional DC-to-DC converter operatively connected to said electrostatic capacitive circuit said bidirectional DC-to-DC converter having switching elements and a control circuit for controlling a direction of energy transfer by controlling switching of said switching elements;

a rotation sensor that detects a rotational speed of said rotary shaft;

a storage battery operatively coupled to said DC-to-DC converter so that said DC-to-DC converter electrically connects said storage battery to said electrostatic capacitive circuit, said storage battery having a lower terminal voltage than a DC terminal voltage of said inverter circuit; and

a control circuit for controlling said inverter circuit, said control circuit operating in the following control modes;

an initial charging mode wherein said electrostatic capacitive circuit is charged with energy from said storage battery through said DC-to-DC converter, if said internal combustion engine is at a standstill;

a starting mode wherein energy stored in said electrostatic capacitive circuit is provided to said squirrel-cage polyphase induction machine as an AC current via said inverter circuit so that said squirrel-cage polyphase induction machine operates as an electric motor, if said internal combustion engine is being started;

a deceleration mode wherein said squirrel-cage polyphase induction machine operates an electric generator by supplying an AC signal having a frequency that is lower than a frequency corresponding to an actual speed detected by said rotational sensor, said AC signal being provided to said electrostatic capacitive circuit via said inverter circuit for charging said electrostatic capacitive circuit, if said vehicle is being braked; and

an acceleration mode wherein said squirrel-cage polyphase induction machine operates an electric motor by supplying an AC signal having a higher frequency than a frequency corresponding to an actual speed detected by said rotational sensor, said electrostatic capacitive circuit providing energy to said squirrel-cage polyphase induction machine via said inverter circuit, if said vehicle is being accelerated.

5. A braking and auxiliary driving means for an internal combustion engine as set forth in claim 2 or 3, and wherein:

a low-voltage side common potential constituting one terminal of said control circuit includes an initial charging mode, wherein said electrostatic capacitive circuit is charged with energy from said storage battery after conversion by said DC-to-DC converter; and

a battery-charging mode wherein, if a terminal voltage of said electrostatic capacitive circuit exceeds a prescribed value, said storage battery is charged with stored electrical energy from said electrostatic capacitive circuit after conversion by said DC-to-DC converter.

6. A braking and auxiliary driving means for an internal combustion engine as set forth in claim 5, wherein said low-voltage side common potential is connected to a potential of said internal combustion engine.

7. A braking and auxiliary driving means for an internal combustion engine as set forth in claim 6, wherein said control modes of said control circuit include an initial charging mode wherein said electrostatic capacitive circuit is charged with energy from said storage battery after conversion by said DC-to-DC converter;

and a battery-charging mode wherein, if a terminal voltage of said electrostatic capacitive circuit exceeds a prescribed value, said storage battery is charged with stored electrical energy from said electrostatic capacitive circuit after conversion by said DC-to-DC converter.

8. A braking and auxiliary driving means for an internal combustion engine as set forth in claim 6, further comprising an electrically insulating material encasing said inverter circuit, control circuit and electrostatic capacitive circuit and a metal container connected to said vehicle body potential having said inverter circuit, control circuit and electrostatic capacitive circuit housed therein.

3. Braking and auxiliary drive apparatus for an internal combustion engine, comprising:

a squirrel-cage polyphase induction machine having a polyphase AC circuit, for coupling]said squirrel-cage polyphase induction machine having a rotary shaft that is directly coupled to a rotary shaft of the internal combustion engine;

an inverter circuit operatively coupled to said polyphase AC circuit of said squirrel-cage polyphase induction machine;

an electricity storage means comprising an electrostatic capacitive circuit operatively coupled to said inverter so that said inverter couples said electrostatic capacitive circuit to said polyphase AC circuit by converting electrical energy in both directions therebetween;

a control circuit that controls said inverter circuit such that in an acceleration mode, said squirrel-cage polyphase induction machine is used as an auxiliary driving means for said internal combustion engine by providing a rotating magnetic field with a velocity that exceeds a rotational speed of said internal combustion engine to said squirrel-cage polyphase induction machine, and in a deceleration mode, said squirrel-cage polyphase induction machine is used as a braking device for said internal combustion engine by providing a rotating magnetic field with a velocity that is less than said rotational speed of said internal combustion engine to said squirrel-cage polyphase induction machine; and

wherein said inverter circuit includes a circuit which, in said acceleration mode, outputs electrical energy stored in said electricity storage means to said squirrel-cage polyphase induction machine as a polyphase AC output, and in said deceleration mode, outputs polyphase AC energy from said squirrel-cage polyphase induction machine to said electricity storage means; and

a storage battery having a lower terminal voltage than a DC terminal voltage of said inverter circuit;

a bidirectional DC-to-DC converter connecting said storage battery to said electrostatic capacitive circuit, said bidirectional DC-to-DC converter having switching elements and a control circuit for controlling a direction of energy transfer by controlling switching of said switching elements.

10. Braking and auxiliary drive apparatus for an internal combustion engine, comprising:

a squirrel-cage polyphase induction machine having a polyphase AC circuit, for coupling]said squirrel-cage polyphase induction machine having a rotary shaft that is directly coupled to a rotary shaft of the internal combustion engine;

an inverter circuit operatively coupled to said polyphase AC circuit of said squirrel-cage polyphase induction machine;

an electricity storage means comprising an electrostatic capacitive circuit operatively coupled to said inverter so that said inverter couples said electrostatic capacitive circuit to said polyphase AC circuit by converting electrical energy in both directions therebetween;

including said internal combustion engine and wherein;

said rotary shaft of the aforementioned internal combustion engine and a rotary shaft of the aforementioned squirrel-cage polyphase induction machine are directly connected;

]

a control circuit that controls said inverter circuit such that in an acceleration mode, said squirrel-cage polyphase induction machine is used as an auxiliary driving means for said internal combustion engine by providing a rotating magnetic field with a velocity that exceeds a rotational speed of said internal combustion engine to said squirrel-cage polyphase induction machine, and in a deceleration mode, said squirrel-cage polyphase induction machine is used as a braking device for said internal combustion engine by providing a rotating magnetic field with a velocity that is less than said rotational speed of said internal combustion engine to said squirrel-cage polyphase induction machine; and

wherein said inverter circuit includes a circuit which, in said acceleration mode, outputs electrical energy stored in said electricity storage means to said squirrel-cage polyphase induction machine as a polyphase AC output, and in said deceleration mode, outputs polyphase AC energy from said squirrel-cage polyphase induction machine to said electricity storage means.