DEVICE FOR INDUCTIVELY TRANSMITTING ENERGY AND METHOD FOR OPERATING A DEVICE FOR INDUCTIVELY TRANSMITTING ENERGY

• US 20160221451A1
• Filed: 07/03/2014
• Published: 08/04/2016
• Est. Priority Date: 09/06/2013
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: PLUM, Thomas, DIEKHANS, Tobias
• Granted Patent: US 10,065,513 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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 53/126 Methods for pairing a vehicle and a charging station, e.g. establishing a one-to-one relation between a wireless power transmitter and a wireless power receiver
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 7/00712 the cycle being controlled or terminated in response to electric parameters
• 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 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

The invention relates to inductive energy transmission from a primary coil (12) to a secondary coil (22) having an additional operating state. By means of this two-sided regulation, a primary-side and secondary-side control of the power electronics is performed in accordance with a predetermined operational strategy. Thus, even in the case of unfavorable coupling factors, for example, the efficiency of the inductive energy transmission can be increased, the magnetic field in the air gap between the primary coil (12) and the secondary coil (22) can be minimized, and the inductive energy transmission can be optimized. This optimized operational strategy is enabled by means of a newly introduced idle state, which permits periodic short-circuiting of the secondary side by means of switches on the secondary side (S5, S6) of the inductive energy transmission system. The invention is preferably used in the charging of the battery of an electric vehicle (4), but other applications are also possible.

Claims

1. A device for inductive energy transmission, the device comprising:

a secondary coil arrangement that is designed to provide an alternating electric voltage between two terminal points when an alternating magnetic field is coupled in;

a rectifier that is designed to rectify the alternating voltage provided by the secondary coil arrangement; and

a switching arrangement that is designed to connect the two terminal points of the secondary coil arrangement together electrically.

2. The device as claimed in claim 1, wherein resonance capacitors are connected in series with the primary coil arrangement, the secondary coil arrangement, or both.

3. The device as claimed in claim 1, wherein the switching arrangement comprises at least one semiconductor switch.

4. The device as claimed in claim 1, wherein the switching arrangement is designed to connect the two terminal points of the secondary coil arrangement together electrically during each half-wave of the provided alternating voltage for a predetermined interval of time.

5. The device as claimed in claim 4, wherein the time interval during which the two terminal points of the secondary coil arrangement are connected together electrically is determined on the basis of a measured electrical parameter in a primary coil arrangement, the secondary coil arrangement, or both.

6. The device as claimed in claim 4, wherein the time interval during which the two terminal points of the secondary coil arrangement are connected together electrically is adjusted adaptively during the energy transmission.

7. The device as claimed in claim 1, wherein the switching arrangement only connects the two terminal points of the secondary coil arrangement together electrically when a primary current in a primary coil arrangement exceeds a predetermined value.

8. An energy transmission device, with

a primary coil arrangement that is designed to provide an alternating magnetic field;

and

a device as claimed in claim 1, wherein the provided alternating magnetic field is at least partially coupled into the secondary coil arrangement.

9. A charging device for an electric vehicle with a device for inductive energy transmission as claimed in claim 1.

10. A method for operating a device for inductive energy transmission, the method comprising:

providing an alternating voltage between two terminal points of a secondary coil arrangement;

electrically connecting the two terminal points of the secondary coil arrangement, wherein two terminal points of the secondary coil arrangement are connected together for a predetermined time interval during each half-wave of the provided alternating voltage.