DEVICE FOR THE INDUCTIVE TRANSFER OF ELECTRICAL ENERGY

• US 20140292263A1
• Filed: 11/09/2011
• Published: 10/02/2014
• Est. Priority Date: 12/14/2010
• Status: Active Grant

• Current Assignee: ENRX IPT GmbH
• Original Assignee: Conductix-Wampfler GmbH (Delachaux Group SA)
• Inventors: Asselin, Pascal
• Granted Patent: US 9,315,110 B2
• Time in Patent Office: Days
• US Class Current: 320/108
• CPC Class Codes: B60L 2210/30 AC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 3/04 Cutting off the power supply under fault conditions protective devices and circuit arrangements in general H01H; H02H
• 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 53/305 Communication interfaces
• CPC Class Codes: B60L 53/53 Batteries
• CPC Class Codes: B60L 53/65 involving identification of vehicles or their battery types
• CPC Class Codes: B60L 58/00 Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• CPC Class Codes: H02J 7/342 The other DC source being a battery actively interacting with the first one, i.e. battery to battery charging with circuits for polarity protection H02J7/0034
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer
• 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
• CPC Class Codes: Y02T 90/16 : Information or communication technologies improving the operation of electric vehicles
• CPC Class Codes: Y02T 90/167 : Systems integrating technologies related to power network operation and communication or information technologies for supporting the interoperability of electric or hybrid vehicles, i.e. smartgrids as interface for battery charging of electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: Y04S 30/14 : Details associated with the interoperability, e.g. vehicle recognition, authentication, identification or billing

Abstract

A device for the inductive transfer of electric energy from a stationary unit having a current supply device and a primary inductance to a vehicle that is adjacent the unit and has a secondary inductance. The vehicle has a secondary control element for adjusting the secondary power taken from the secondary inductance and comprises a control device enabling the withdrawn secondary power to be modified in steps. The stationary unit comprises a primary control element for adjusting the primary power and a first measuring device enabling an operational parameter, influenced by the secondary power, of the current supply device to be measured. The primary control element adjusts the primary power which can be injected in accordance with modifications of the operational parameter. The secondary power can be switched by the switching device and has in one of the steps, a value which is at least approximately zero.

Claims

1. Device for inductive transfer of electrical energy from a stationary unit having a current supply device and a primary inductance connected thereto to a vehicle having a secondary inductance and situated adjacent to the stationary unit, wherein the vehicle has a secondary control element for adjusting the secondary power withdrawn from the secondary inductance, said secondary control element containing a switching device by means of which the withdrawn secondary power can be varied stepwise, in that the stationary unit has a primary control element for adjusting the primary power injectable into the primary inductance and containing a first measuring device, by means of which an electrical parameter of the current supply device that is influenced by the secondary power can be measured, and in that the primary control element adjusts the injectable primary power on the basis of changes of said operating parameter measured by the measuring device.

2. Device according to claim 1, wherein the secondary power can be switched by the switching device between two steps, and in that the secondary power has at least approximately the value zero in one of the steps.

3. Device according to claim 1, wherein a battery, which is charged during operation of the device with a charging current (I_B) generated from the current (I_S) of the secondary inductance, is arranged in the vehicle, in that the secondary control element has a second measuring device by means of which the charging current (I_B) can be measured, and in that the secondary control element contains a computing device which, if the value of the charging current (I_B) measured by the second measuring device deviates from a target value, determines a temporal sequence of switching processes depending on the ratio between the target value and the measured value of the charging current (I_B), which are executed by the switching device.

4. Device according to claim 3, wherein the temporal sequence of the switching processes contains a code that indicates whether the deviation of the measured value for the charging current (I_B) from a target value is positive or negative.

5. Device according to claim 3, wherein the primary control element changes the value of the injectable primary current on the basis of the temporal sequence of changes of the operating parameter when there are abrupt changes of the operating parameter measured by the first measuring device.

6. Device according to claim 3, wherein the secondary power can be switched by the switching device between two steps, in that a periodic switching between the steps in a predetermined time cycle takes place if the target value of the charging current (I_B) is exceeded by the measured value, wherein the duty ratio of the switching between the steps corresponds to the ratio between the target value and the measured value of the charging current (I_B), and in that the primary control element changes the value of the injectable primary power depending on the duty ratio of the changes of the operating parameter when there are abrupt changes of the operating parameter measured by the first measuring device.

7. Device according to claim 3, wherein the secondary power can be switched by the switching device between two steps, and in that if the target value of the charging current (I_B) is exceeded by the value measured by the second measuring device, the secondary power is switched from the higher to the lower step until an operating parameter of the secondary inductance, or of a circuit connecting it to the battery, dependent in the lower step on the injectable primary power and measurable by the second measuring device, reaches a value at which a switch to the higher step leads to a congruence of the charging current with its target value (I_B), and in that in the event of an abrupt change of the operating parameter measured by the first measuring device, the primary control element reduces the value of the injectable primary power at a predetermined rate over time until there is a further abrupt change of the operating parameter measured by the measuring device.

8. Device according to claim 7, wherein the operating parameter that can be measured by the second measuring device is the current (I_S) conducted by the secondary inductance, or the output current (I₁) of a balancing network connected downstream of the secondary inductance, or the output current (I₂) of a converter upstream of the battery.

9. Device according to claim 4, wherein the injectable primary current is increased by the primary control element by a predetermined step or at a predetermined rate over time in the presence of the code indicating that the measured value has fallen below the target value of the charging current (I_B).

10. Device according to claim 1, wherein the operating parameter of the current supply device measured by the first measuring device is the voltage (U_P) present at the primary coil, or the output current (I₃) or the input current (I₄) of an inverter present in the current supply device, or the current (I_N) received by the current supply device from the current supply network.

11. Device according to claim 1, wherein the switching device is a two-pole switch that is connected in parallel to the secondary inductance or to the output of a balancing network connected downstream of the secondary inductance, or to the output (I₂) of a converter connected upstream of the battery.

12. Device according to claim 1, wherein the switching device is a two-pole switch that is connected in parallel or in series to at least one element of a balancing network connected downstream of the secondary inductance, so that the function of the balancing network depends on the switch position.