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US6066928A Expired / Lapsed US ⏱️ 0.0 years remaining

Electric system for electric vehicle

Assignee: Fuji Electric Co Ltd
•
Filing: 1998-12-15
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Granted: 2000-05-23
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Expires: 2018-12-15
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Abstract

Abstract An electric system for an electric vehicle includes a voltage type inverter that receives dc input voltage from a dc input circuit, and generates variable ac voltage of a variable frequency, and an ac motor including a plurality of windings each of which has one end connected to an ac output terminal of the voltage type inverter, the other ends of the windings being connected together to provide a neutral point of motor windings. A variable-voltage energy storage element is connected between the neutral point and a connecting point provided in the dc input circuit, and an on-vehicle dc power supply is connected to the opposite ends of the energy storage element or input terminals of the dc input circuit. The inverter performs switching operations in a zero-voltage vector mode, to operate as a chopper, so that power is transferred between the variable-voltage energy storage element, and the dc input side of the inverter.

Inventors

  • 👤 Shigenori Kinoshita
  • 👤 Koetsu Fujita
  • 👤 Junichi Ito

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 13:44
CPC Classifications
B; B60; B60L; B60L7/00; B60L7/10; B60L50/00; B60L50/40; B60L58/00; B60L58/10; H; H02; H02P; H02P2209/00; H02P2209/01; Y; Y02; Y02T; Y02T10/00; Y02T10/60; Y02T10/64; Y02T10/70

Claims Analysis

Total Claims: 42
Claim 1
Independent Claim 120 words
An electric system for an electric vehicle, comprising: a dc input circuit; a voltage type inverter that is connected to said dc input circuit to receive input voltage from said dc input circuit, and generate variable ac voltage of a variable frequency; an ac motor including a plurality of windings each of which has one end connected to an ac output terminal of said voltage type inverter, the other ends of said windings being connected together to provide a neutral point of motor windings; a variable-voltage energy storage element connected between said neutral point and a connecting point provided in said dc input circuit; and an on-vehicle dc power supply connected to opposite ends of said variable-voltage energy storage element.
Claim 2
Dependent Claim 120 words
An electric system for an electric vehicle, comprising: a dc input circuit; a voltage type inverter that is connected to said dc input circuit to receive input voltage from said dc input circuit, and generate variable ac voltage of a variable frequency; an ac motor including a plurality of windings each of which has one end connected to an ac output terminal of said voltage type inverter, the other ends of said windings being connected together to provide a neutral point of motor windings; a variable-voltage energy storage element connected between said neutral point and a connecting point provided in said dc input circuit; and an on-vehicle dc power supply connected to opposite ends of said variable-voltage energy storage element.
Claim 3
Dependent Claim 125 words
An electric system for an electric vehicle, comprising: a dc input circuit including input terminals; a voltage type inverter that is connected to said dc input circuit to receive dc input voltage from said dc input circuit, and generate variable ac voltage of a variable frequency; an ac motor including a plurality of windings each of which has one end connected to an ac output terminal of said voltage type inverter, the other ends of said windings being connected together to provide a neutral point of the motor windings; a variable-voltage energy storage element connected between said neutral point and a connecting point provided in said dc input circuit; and an on-vehicle dc power supply connected to said input terminals of said dc input circuit.
Claim 4
Dependent Claim 125 words
An electric system for an electric vehicle, comprising: a dc input circuit including input terminals; a voltage type inverter that is connected to said dc input circuit to receive dc input voltage from said dc input circuit, and generate variable ac voltage of a variable frequency; an ac motor including a plurality of windings each of which has one end connected to an ac output terminal of said voltage type inverter, the other ends of said windings being connected together to provide a neutral point of the motor windings; a variable-voltage energy storage element connected between said neutral point and a connecting point provided in said dc input circuit; and an on-vehicle dc power supply connected to said input terminals of said dc input circuit.
Claim 5
Dependent Claim 38 words
An electric system for an electric vehicle according to claims 1, wherein said variable-voltage storage element is connected to one of output terminals of said dc input circuit as said connecting point provided in said dc input circuit.
Claim 6
Dependent Claim 40 words
An electric system for an electric vehicle according to claim 1, wherein said variable-voltage storage element is connected to a middle point of output terminals of said dc input circuit as said connecting point provided in said dc input circuit.
Claim 7
Dependent Claim 72 words
An electric system for an electric vehicle according to claim 1, wherein said dc input circuit comprises a semiconductor switch arm comprising a series circuit of two semiconductor switching devices each of which is connected in parallel with a diode in a reverse direction, and wherein said variable-voltage energy storage element is connected to a middle point of said semiconductor switch arm as said connecting point provided in said dc input circuit.
Claim 8
Dependent Claim 38 words
An electric system for an electric vehicle according to claim 2, wherein said variable-voltage storage element is connected to one of output terminals of said dc input circuit as said connecting point provided in said dc input circuit.
Claim 9
Dependent Claim 40 words
An electric system for an electric vehicle according to claim 2, wherein said variable-voltage storage element is connected to a middle point of output terminals of said dc input circuit as said connecting point provided in said dc input circuit.
Claim 10
Dependent Claim 72 words
An electric system for an electric vehicle according to claim 2, wherein said dc input circuit comprises a semiconductor switch arm comprising a series circuit of two semiconductor switching devices each of which is connected in parallel with a diode in a reverse direction, and wherein said variable-voltage energy storage element is connected to a middle point of said semiconductor switch arm as said connecting point provided in said dc input circuit.
Claim 11
Dependent Claim 39 words
An electric system for an electric vehicle according to claim 1, wherein said inverter operates as a chopper in a zero-voltage vector mode, so that power is transferred between said variable-voltage energy storage element and said dc input circuit.
Claim 12
Dependent Claim 39 words
An electric system for an electric vehicle according to claim 2, wherein said inverter operates as a chopper in a zero-voltage vector mode, so that power is transferred between said variable-voltage energy storage element and said dc input circuit.
Claim 13
Dependent Claim 52 words
An electric system for an electric vehicle according to claim 5, wherein said semiconductor switching arm is turned on and off to perform a chopper operation while said inverter is operating in a zero-voltage vector mode, so that power is transferred between said variable-voltage energy storage element and said dc input circuit.
Claim 14
Dependent Claim 52 words
An electric system for an electric vehicle according to claim 8, wherein said semiconductor switching arm is turned on and off to perform a chopper operation while said inverter is operating in a zero-voltage vector mode, so that power is transferred between said variable-voltage energy storage element and said dc input circuit.
Claim 15
Dependent Claim 41 words
An electric system for an electric vehicle according to claim 4, wherein the middle point of the output terminals of said dc input circuit is provided by a connecting point of a plurality of input capacitors that are connected in series.
Claim 16
Dependent Claim 41 words
An electric system for an electric vehicle according to claim 7, wherein the middle point of the output terminals of said dc input circuit is provided by a connecting point of a plurality of input capacitors that are connected in series.
Claim 17
Dependent Claim 29 words
An electric system for an electric vehicle according to claim 1, wherein said variable-voltage energy storage element comprises one of an electric double layer capacitor and an electrochemical capacitor.
Claim 18
Dependent Claim 29 words
An electric system for an electric vehicle according to claim 2, wherein said variable-voltage energy storage element comprises one of an electric double layer capacitor and an electrochemical capacitor.
Claim 19
Dependent Claim 31 words
An electric system for an electric vehicle according to claim 1, further comprising a capacitor for absorbing high-frequency current, said capacitor being connected in parallel with said variable-voltage energy storage element.
Claim 20
Dependent Claim 31 words
An electric system for an electric vehicle according to claim 2, further comprising a capacitor for absorbing high-frequency current, said capacitor being connected in parallel with said variable-voltage energy storage element.
Claim 21
Dependent Claim 45 words
An electric system for an electric vehicle according to claim 1, wherein a voltage of the variable-voltage energy storage element or the dc voltage applied to said voltage type inverter is controlled to be constant, or variable depending upon operating conditions of said ac motor.
Claim 22
Dependent Claim 45 words
An electric system for an electric vehicle according to claim 2, wherein a voltage of the variable-voltage energy storage element or the dc voltage applied to said voltage type inverter is controlled to be constant, or variable depending upon operating conditions of said ac motor.
Claim 23
Dependent Claim 23 words
An electric system for an electric vehicle according to claim 1, wherein said ac motor is an electric motor for driving the vehicle.
Claim 24
Dependent Claim 23 words
An electric system for an electric vehicle according to claim 2, wherein said ac motor is an electric motor for driving the vehicle.
Claim 25
Dependent Claim 25 words
An electric system for an electric vehicle according to claim 1, wherein said ac motor is an electric motor for driving accessories of the vehicle.
Claim 26
Dependent Claim 25 words
An electric system for an electric vehicle according to claim 2, wherein said ac motor is an electric motor for driving accessories of the vehicle.
Claim 27
Dependent Claim 38 words
An electric system for an electric vehicle according to claim 3, wherein said dc input circuit comprises a capacitor connected between the output terminals of said dc input circuit as an input capacitor of said voltage type inverter.
Claim 28
Dependent Claim 38 words
An electric system for an electric vehicle according to claim 6, wherein said dc input circuit comprises a capacitor connected between the output terminals of said dc input circuit as an input capacitor of said voltage type inverter.
Claim 29
Dependent Claim 21 words
An electric system of an electric vehicle according to claim 1, wherein said on-vehicle dc power supply comprises a chemical battery.
Claim 30
Dependent Claim 21 words
An electric system of an electric vehicle according to claim 2, wherein said on-vehicle dc power supply comprises a chemical battery.
Claim 31
Dependent Claim 21 words
An electric system for an electric vehicle according to claim 1, wherein said on-vehicle dc power supply comprises an engine generator.
Claim 32
Dependent Claim 21 words
An electric system for an electric vehicle according to claim 2, wherein said on-vehicle dc power supply comprises an engine generator.
Claim 33
Dependent Claim 21 words
An electric system for an electric vehicle according to claim 1, wherein said on-vehicle dc power supply comprises a fuel battery.
Claim 34
Dependent Claim 21 words
An electric system for an electric vehicle according to claim 2, wherein said on-vehicle dc power supply comprises a fuel battery.
Claim 35
Dependent Claim 49 words
An electric system of an electric vehicle according to claim 3, wherein the dc voltage Vi applied to said voltage type inverter, a voltage Vc of said variable-voltage energy storage element, and a terminal voltage (between lines) Vm of said ac motor have relationships as represented by Vi≧Vc+Vm/√3 Vi--Vm/√3≧Vc≧Vm/√3.
Claim 36
Dependent Claim 50 words
An electric system of an electric vehicle according to claim 6, wherein the dc voltage Vi applied to said voltage type inverter, a voltage Vc of said variable-voltage energy storage element, and a terminal voltage (between lines) Vm of said ac motor have relationships as represented by Vi≧Vc+Vm/√3 Vi-Vm/√3≧Vc≧Vm/√3. 35.
Claim 37
Dependent Claim 49 words
An electric system for an electric vehicle according to claim 4, wherein the dc voltage Vi applied to said voltage type inverter, a voltage Vc of said variable-voltage energy storage element, and a terminal voltage (between lines) Vm of said ac motor have relationships as represented by Vi/2-Vm/√3≧Vc≧Vm/√3-Vi/2 Vi≧2(Vc+Vm/√3).
Claim 38
Dependent Claim 49 words
An electric system for an electric vehicle according to claim 7, wherein the dc voltage Vi applied to said voltage type inverter, a voltage Vc of said variable-voltage energy storage element, and a terminal voltage (between lines) Vm of said ac motor have relationships as represented by Vi/2-Vm/√3≧Vc≧Vm/√3-Vi/2 Vi≧2(Vc+Vm/√3).
Claim 39
Dependent Claim 49 words
An electric system for an electric vehicle according to claim 5, wherein the dc voltage Vi applied to said voltage type inverter, a voltage Vc of said variable-voltage energy storage element, and a terminal voltage (between lines) Vm of said ac motor have relationships as represented by Vi≧Vc+Vm/√3 0≦Vc≦Vi-Vm/√3.
Claim 40
Dependent Claim 49 words
An electric system for an electric vehicle according to claim 8, wherein the dc voltage Vi applied to said voltage type inverter, a voltage Vc of said variable-voltage energy storage element, and a terminal voltage (between lines) Vm of said ac motor have relationships as represented by Vi≧Vc+Vm/√3 0≧Vc≧Vi-Vm/√3.
Claim 41
Dependent Claim 50 words
An electric system for an electric vehicle according to claim 5, wherein the dc voltage Vi applied to said voltage type inverter Vi, a voltage Vc of said variable-voltage energy storage element, and a terminal voltage (between lines) Vm of said ac motor have relationships as represented by Vi≧Vc+Vm/√3 0≦Vc≦Vi/3.
Claim 42
Dependent Claim 50 words
An electric system for an electric vehicle according to claim 8, wherein the dc voltage Vi applied to said voltage type inverter Vi, a voltage Vc of said variable-voltage energy storage element, and a terminal voltage (between lines) Vm of said ac motor have relationships as represented by Vi≧Vc+Vm/√3 0≦Vc≦Vi/3.

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2003-05-23 2003-11-22 2004-05-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2007-05-23 2007-11-22 2008-05-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2011-05-23 2011-11-22 2012-05-23 $7700.00 Window Closed / Lapsed

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