CONTACTLESS POWER TRANSFER SYSTEM

• US 20130293192A1
• Filed: 01/18/2012
• Published: 11/07/2013
• Est. Priority Date: 01/19/2011
• Status: Active Grant

• Current Assignee: Technova, Inc. (Aisin Corp.), National University Corporation Saitama University
• Original Assignee: Technova, Inc. (Aisin Corp.), National University Corporation Saitama University
• Inventors: Abe, Shigeru, Yasuda, Tomio, Suzuki, Akira, Yamanouchi, Ryouichi
• Granted Patent: US 9,266,441 B2
• Time in Patent Office: Days
• US Class Current: 320/108
• CPC Class Codes: B60L 15/007 Physical arrangements or structures of drive train converters specially adapted for the propulsion motors of electric vehicles
• 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 2220/54 Windings for different functions
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 53/12 Inductive energy transfer
• CPC Class Codes: B60L 53/122 Circuits or methods for driving the primary coil, e.g. supplying electric power to the coil
• CPC Class Codes: B60L 53/24 Using the vehicle's propulsion converter for charging
• CPC Class Codes: B60L 53/36 by positioning the vehicle
• CPC Class Codes: B60M 7/003 for vehicles using stored power (e.g. charging stations)
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 2310/48 for electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02M 1/007 Plural converter units in cascade push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826
• CPC Class Codes: H02M 3/33571 Half-bridge at primary side of an isolation transformer
• CPC Class Codes: H02M 7/217 using semiconductor devices only
• 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
• CPC Class Codes: Y02T 90/12 : Electric charging stations
• CPC Class Codes: Y02T 90/14 : Plug-in electric vehicles

Abstract

A half-bridge inverter is used for a high frequency alternating current power supply to be connected to a primary side of a contactless power transformer, and a voltage-doubler rectifier is used to convert a secondary-side alternating current output of the contactless power transformer into a direct current.

Claims

1. A contactless power transfer system in which a high frequency alternating current power supply is connected to a primary side of a contactless power transformer and a rectifier which converts a secondary-side alternating current output into a direct current is connected to a secondary side of the contactless power transformer,

wherein the high frequency alternating current power supply is formed of a half-bridge inverter and the half-bridge inverter is connected to the primary side of the contactless power transformer through a series capacitor,

the rectifier is formed of a voltage-doubler rectifier and the voltage-doubler rectifier is connected to the secondary side of the contactless power transformer through a parallel capacitor,

the voltage-doubler rectifier includes:

a capacitor arm in which two capacitors C1 and C2 are connected in series,

a first diode D1 which is inserted between one end of the capacitor arm and one end of a secondary-side circuit of the contactless power transformer so as to make the capacitor arm the forward side, and

a second diode D2 which is inserted between another end of the capacitor arm and the one end of the secondary-side circuit so as to make the capacitor arm the reverse direction side, and

a central point of the capacitor arm is connected to another end of the secondary-side circuit.

2. The contactless power transfer system according to claim 1, further comprising:

a high power factor boost rectifier which is used as a direct current power supply of the half-bridge inverter.

3. The contactless power transfer system according to claim 2, wherein an output voltage of the voltage-doubler rectifier is adjusted by adjusting an output voltage of the high power factor boost rectifier.

4. The contactless power transfer system according to claim 3, further comprising:

a constant voltage control circuit which performs constant-voltage control on the high power factor boost rectifier having the output voltage of the half-bridge inverter or the voltage-doubler rectifier as a feedback input,

wherein a conduction ratio of the high power factor boost rectifier is controlled based on the output voltage of the constant voltage control circuit.

5. The contactless power transfer system according to claim 3, further comprising:

a constant current control circuit which performs constant current control on the high power factor boost rectifier having an output current of the half-bridge inverter or the voltage-doubler rectifier as a feedback input,

wherein a conduction ratio of the high power factor boost rectifier is controlled based on the output voltage of the constant current control circuit.

7. The contactless power transfer system according to claim 1, wherein the primary side of the contactless power transformer is provided on the ground and the secondary side is provided in a moving body such as a vehicle, a carrier, and a moving robot.

8. The contactless power transfer system according to claim 1, wherein an output of the voltage-doubler rectifier is connected to a secondary battery and a series of control required to charge the secondary battery is controlled by controlling the conduction ratio of the high power factor boost rectifier.

9. The contactless power transfer system according to claim 2, wherein the high power factor boost rectifier is a bridgeless high power factor boost rectifier which does not have a bridge.

10. The contactless power transfer system according to claim 7, wherein the moving body in which the secondary side of the contactless power transformer is provided includes a first power converter having a function of converting a direct current into an alternating current and a function of converting the alternating current into the direct current, a secondary battery which is charged by the direct current converted by the first power converter, two capacitors which are interposed between the secondary battery and the first power converter, and a rotating electrical machine which is driven by the alternating current converted by the first power converter,

the first power converter includes at least one of switching unit arms in which two switching units formed of a semiconductor switching element and a freewheeling diode are connected in series,

when the secondary battery is charged by the secondary-side alternating current output of the contactless power transformer, semiconductor switching elements of all switching units which constitute the first power converter are off, and a voltage-doubler rectifier is formed by a freewheeling diode of the two switching units which are connected in series and the two capacitors.

11. The contactless power transfer system according to claim 10, further comprising:

a second power converter, which is capable of boosting and dropping a direct current voltage, provided between the secondary battery and the two capacitors,

wherein when the first power converter converts the direct current output of the secondary battery into the alternating current to drive the rotating electrical machine, the second power converter boosts the direct current voltage of the secondary battery to output the boosted direct current voltage to the first power converter and when the secondary battery is charged, the second power converter drops the direct current voltage output from the voltage-doubler rectifier in accordance with a remaining battery level of the secondary battery to output the direct current voltage to the secondary battery.

6. (canceled)