Electric system for electric vehicle
First Claim
1. 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.
1 Assignment
0 Petitions
Accused Products
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.
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Citations
40 Claims
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1. 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. - View Dependent Claims (3, 4, 5, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39)
- 35. 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
- space="preserve" listing-type="equation">Vi/2-Vm/√
3≧
Vc≧
Vm/√
3-Vi/2
space="preserve" listing-type="equation">Vi≧
2(Vc+Vm/√
3). - space="preserve" listing-type="equation">Vi/2-Vm/√
-
- 37. 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
- space="preserve" listing-type="equation">Vi≧
Vc+Vm/√
3
space="preserve" listing-type="equation">0≦
Vc≦
Vi-Vm/√
3. - space="preserve" listing-type="equation">Vi≧
- space="preserve" listing-type="equation">Vi≧
Vc+Vm/√
3
space="preserve" listing-type="equation">0≦
Vc≦
Vi/3.
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2. 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. - View Dependent Claims (6, 7, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40)
- 36. 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
- space="preserve" listing-type="equation">Vi/2-Vm/√
3≧
Vc≧
Vm/√
3-Vi/2
space="preserve" listing-type="equation">Vi≧
2(Vc+Vm/√
3). - space="preserve" listing-type="equation">Vi/2-Vm/√
-
- 38. 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
- space="preserve" listing-type="equation">Vi≧
Vc+Vm/√
3
space="preserve" listing-type="equation">0≧
Vc≧
Vi-Vm/√
3. - space="preserve" listing-type="equation">Vi≧
- space="preserve" listing-type="equation">Vi≧
Vc+Vm/√
3
space="preserve" listing-type="equation">0≦
Vc≦
Vi/3.
Specification