Power transmission apparatus

• US 8,733,480 B2
• Filed: 08/25/2008
• Issued: 05/27/2014
• Est. Priority Date: 08/27/2007
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toyota Chuo Kenkyusho (Toyota Motor Corporation), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Kabushiki Kaisha Toyota Chuo Kenkyusho (Toyota Motor Corporation), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Watanabe, Takao, Nishizawa, Hiroyuki, Kitahata, Takeshi, Tsuchiya, Eiji
• Primary Examiner(s): MULLINS, BURTON S
• Application Number:
  US12/675,416
• Publication Number:
  US 20100219706A1
• Time in Patent Office: 2,101 Days
• Field of Search: 310/114, 180/65.1, 180/65.21, 180/65.31, 180/65.22, 180/65.275, 180/383, 477/3, 901902-903, 901/906, 901917-918, 901/945
• US Class Current: 180/65.22
• CPC Class Codes: B60K 1/02 comprising more than one electric motor
• CPC Class Codes: B60K 2006/262 the motor or generator are used as clutch, e.g. between engine and driveshaft
• CPC Class Codes: B60K 2006/4833 Step up or reduction gearing driving generator, e.g. to operate generator in most efficient speed range
• CPC Class Codes: B60K 6/22 characterised by apparatus, components or means specially adapted for HEVs
• CPC Class Codes: B60K 6/26 characterised by the motors or the generators
• CPC Class Codes: B60K 6/36 characterised by the transmission gearings
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/448 Electrical distribution type
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60K 6/543 the transmission being a continuously variable transmission
• CPC Class Codes: B60L 15/2054 by controlling transmissions or clutches
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 2210/30 AC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2220/42 with use of more than one motor
• CPC Class Codes: B60L 2220/52 Clutch motors
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• 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 20/15 : Control strategies specially adapted for achieving a particular effect
• CPC Class Codes: B60W 20/30 : Control strategies involving selection of transmission gear ratio control of change speed gearings, together with other vehicle sub-units B60W10/10; HEV transmission gearing B60K6/36; gearings and control thereof F16H
• CPC Class Codes: B60W 2510/081 : Speed
• CPC Class Codes: B60W 2710/083 : Torque
• CPC Class Codes: H02K 16/00 : Machines with more than one rotor or stator machines for transmitting mechanical power from a driving shaft to a driven shaft and comprising structurally interrelated motor and generator parts H02K51/00; permanent magnet machines with multiple rotors or stators relatively rotated for vectorially combining the excitation fields or the armature voltages H02K21/029
• CPC Class Codes: H02K 16/025 : with rotors and moving stators connected in a cascade cascade arrangement of an asynchronous motor with another dynamo-electric motor or converter H02K17/34
• CPC Class Codes: H02K 17/36 : with another asynchronous induction motor
• CPC Class Codes: H02K 47/00 : Dynamo-electric converters
• CPC Class Codes: H02K 51/00 : Dynamo-electric gears, i.e. dynamo-electric means for transmitting mechanical power from a driving shaft to a driven shaft and comprising structurally interrelated motor and generator parts
• CPC Class Codes: H02K 7/006 : Structural association of a motor or generator with the drive train of a motor vehicle
• CPC Class Codes: H02K 7/116 : with gears
• 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

Abstract

A rotational difference is generated between a first and a second rotor and a third rotor, which causes an induced current to flow in a first rotor winding. This causes a torque to act between the first rotor and the third rotor. The rotary magnetic field generated by the induced current flowing through a second rotor winding interacts with a second stator, which in turn generates an induced electromotive force in a second stator winding. The induced electromotive force is applied via a phase adjustment circuit to a first stator winding, which generates a rotary magnetic field and causes a torque to act between the first stator and the third rotor. The rotary magnetic field generated by the second rotor winding and the induced current flowing in the second stator winding causes a torque to act between the second stator and the second rotor.

Claims

1. A power transmission apparatus comprising:

a first rotary element having a rotary element conductor that can generate a rotary magnetic field;

a stationary element having a stationary element conductor that can generate a rotary magnetic field;

a second rotary element that can rotate relative to the first rotary element; and

an engaging apparatus that can mechanically engage one of the first rotary element and the second rotary element with the other of the first rotary element and the second rotary element,

wherein a torque acts between the first rotary element and the second rotary element according to the rotary magnetic field generated by the rotary element conductor, and a torque acts between the stationary element and the second rotary element according to the rotary magnetic field generated by the stationary element conductor,

wherein the rotary element conductor can generate the rotary magnetic field when induced current flows according to a rotational difference generated between the first rotary element and the second rotary element,

wherein power of a prime mover is transmitted to one of the first rotary element and the second rotary element and power of the other of the first rotary element and the second rotary element is transmitted to a load,

wherein the power transmission apparatus further comprises;

a transmission configured to transmit power from the other of the first rotary element and the second rotary element to the load while changing speed,

an electric power transmission unit configured to take out AC power from the rotary element conductor, and

an electric power conversion unit configured to convert the AC power taken out by the electric power transmission unit and supply converted electric power to the stationary element conductor, and

wherein when the power of the prime mover is used to drive the load, a gear ratio of the transmission is changed to a smaller side so that a rotational speed of one of the first rotary element and the second rotary element, to which the power is transmitted from the prime mover, is maintained to be higher than a rotational speed of the other rotary element that transmits the power to the load as a rotational speed of the load becomes higher.

2. The power transmission apparatus according to claim 1, wherein the electric power conversion unit includes

a rectifier configured to rectify the AC power taken out by the electric power transmission unit, and

a DC-DC converter configured to convert a voltage of the electric power rectified by the rectifier into a voltage to be output,

wherein the electric power which voltage is converted by the DC-DC converter is converted by an inverter into an AC electric power to be supplied to the stationary element conductor.

3. The power transmission apparatus according to claim 1, wherein the electric power transmission unit includes

an electric power transmitting rotary element coupled with the first rotary element, wherein the electric power transmitting rotary element is connected to the rotary element conductor of the first rotary element and having an electric power transmitting rotary element conductor that can generate a rotary magnetic field, and

an electric power transmitting stationary element having an electric power transmitting stationary element conductor through which induced current flows according to the rotary magnetic field generated by the electric power transmitting rotary element conductor,

wherein the electric power conversion unit is configured to convert AC power generated by the electric power transmitting stationary element conductor.

4. The power transmission apparatus according to claim 3, wherein phases of the first rotary element conductor are opposite to that of phases of the electric power transmitting rotary element conductor.

5. The power transmission apparatus according to claim 1, wherein the electric power transmission unit includes

a brush connected to the electric power conversion unit, and

a slip ring connected to the rotary element conductor of the first rotary element and rotating together with the first rotary element while causing slip relative to the brush.

6. A power transmission apparatus comprising:

a first rotary element having a rotary element conductor that can generate a rotary magnetic field;

a stationary element having a stationary element conductor that can generate a rotary magnetic field;

a second rotary element that can rotate relative to the first rotary element, wherein a torque acts between the first rotary element and the second rotary element according to the rotary magnetic field generated by the rotary element conductor, and a torque acts between the stationary element and the second rotary element according to the rotary magnetic field generated by the stationary element conductor; and

an engaging apparatus that can mechanically engage one of the first rotary element and the second rotary element with the other of the first rotary element and the second rotary element,

wherein the rotary element conductor can generate the rotary magnetic field when induced current flows according to a rotational difference generated between the first rotary element and the second rotary element,

wherein power of a prime mover is transmitted to one of the first rotary element and the second rotary element and power of the other of the first rotary element and the second rotary element is transmitted to a load,

wherein the power transmission apparatus further comprises;

a transmission configured to transmit the power from the other of the first rotary element and the second rotary element to the load while changing speed,

an electric power transmission unit configured to take out AC power from the rotary element conductor, and

an electric power conversion unit configured to convert the AC power taken out by the electric power transmission unit and supply converted electric power to the stationary element conductor,

wherein the electric power conversion unit includes a rectifier configured to rectify the AC power taken out by the electric power transmission unit, and a DC-DC converter configured to convert a voltage of the electric power rectified by the rectifier into a voltage to be output,

wherein the electric power which voltage is converted by the DC-DC converter is converted by an inverter into an AC electric power to be supplied to the stationary element conductor, and

wherein a voltage conversion ratio of the DC-DC converter is decreased if a rotational speed of one of the first rotary element and the second rotary element is higher than a rotational speed of the other.

7. A power transmission apparatus comprising:

a first rotary element having a rotary element conductor that can generate a rotary magnetic field;

a stationary element having a stationary element conductor that can generate a rotary magnetic field;

a second rotary element that can rotate relative to the first rotary element, wherein a torque acts between the first rotary element and the second rotary element according to the rotary magnetic field generated by the rotary element conductor, and a torque acts between the stationary element and the second rotary element according to the rotary magnetic field generated by the stationary element conductor; and

an engaging apparatus that can mechanically engage one of the first rotary element and the second rotary element with the other of the first rotary element and the second rotary element,

wherein the rotary element conductor can generate the rotary magnetic field when induced current flows according to a rotational difference generated between the first rotary element and the second rotary element,

wherein power of a prime mover is transmitted to one of the first rotary element and the second rotary element and power of the other of the first rotary element and the second rotary element is transmitted to a load,

wherein the power transmission apparatus further comprises;

a transmission configured to transmit the power from the other of the first rotary element and the second rotary element to the load while changing speed,

an electric power transmission unit configured to take out AC power from the rotary element conductor, and

an electric power conversion unit configured to convert the AC power taken out by the electric power transmission unit and supply converted electric power to the stationary element conductor,

wherein the electric power conversion unit includes a rectifier configured to rectify the AC power taken out by the electric power transmission unit, and a DC-DC converter configured to convert a voltage of the electric power rectified by the rectifier into a voltage to be output,

wherein the electric power which voltage is converted by the DC-DC converter is converted by an inverter into an AC electric power to be supplied to the stationary element conductor, and

wherein when the power of the prime mover is used to drive the load, a voltage conversion ratio of the DC/DC converter is reduced to reduce the torque acting between the first rotary element and the second rotary element on the condition that an output voltage of the DC-DC converter is higher than a voltage of an electric storage apparatus.