Method and device for non-contact energy transmission

• US 20040051628A1
• Filed: 04/25/2003
• Published: 03/18/2004
• Est. Priority Date: 10/27/2000
• Status: Active Grant

• Current Assignee: Sew-Eurodrive GmbH & Company KG (BV Beteiligung GmbH & Company KG)
• Original Assignee: Sew-Eurodrive GmbH & Company KG (BV Beteiligung GmbH & Company KG)
• Inventors: Uhl, Thomas
• Granted Patent: US 7,276,812 B2
• Time in Patent Office: Days
• US Class Current: 340/310.01
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02M 1/44 Circuits or arrangements for compensating for electromagnetic interference in converters or inverters
• CPC Class Codes: H02M 3/1584 with a plurality of power processing stages connected in parallel

Abstract

A method and a device for non-contact energy transmission from one or more medium-frequency current sources, whose medium frequencies may have deviations around f_M, to one or more moving consumers via one or more transmission lines and from or via transformer heads, allocated to the moving consumers, having one or more downstream matching controllers for adjusting the power received from the transmission lines; the transmission lines are fed from the medium-frequency current sources with currents which are constant in their effective values; the currents fed into a matching controller are in each case rectified in a rectifier, smoothed in each instance by a link-circuit reactor and brought together; with the aid of a single switch, this link-circuit current is either supplied to the link-circuit capacitor buffering the output voltage of the matching controller or is shunted upstream of this link-circuit capacitor, depending upon the power demand of the consumers connected to the matching controller; the switching frequency of the switch is selected as a fixed value from a 10%-wide tolerance band around 1/f_M; the output voltages of a plurality of matching controllers are able to be parallel-connected via diodes for supplying a consumer.

Claims

1. A method for non-contact transmission of electric power from one or more medium-frequency current sources, whose frequencies may have deviations around medium frequency f_M, to at least one moving consumer via one or more transmission lines and transformer heads, allocated to the consumers, having a downstream matching controller for adjusting the power received from the transmission line;

a transmission line being fed from a medium-frequency current source with a medium-frequency current that is constant in its effective value during power transmission;

the respective consumer being supplied with energy from at least one matching controller having at least one feed-in, one or more supplied currents being rectified in one rectifier each, smoothed by one link-circuit reactor each, and brought together;

with the aid of a switch, the link-circuit current, brought together in each instance, either being supplied to a link-circuit capacitor buffering output voltage U₌ of the matching controller, or being shunted upstream of the link-circuit capacitor, depending upon the power demand of the consumers;

and the respective switch being switched in such a way that switching frequency 1/T is less than double the medium frequency, thus, 1/T<

2f_M.

2. The method as recited in claim 1,

wherein the switching frequency 1/T is selected as a value between 0.5 fm and 1.5 f_M.

3. The method as recited in at least one of the preceding claims,

wherein the switch is switched asynchronously with respect to one or more medium-frequency feed-ins, and/or the switch is switched periodically with a frequency 1/T in such a way in that there is no constant phase relationship to the currents of one or more feed-ins.

4. The method as recited in at least one of the preceding claims,

wherein the link-circuit reactor is designed such that the link-circuit current does not pulsate during operation.

5. The method as recited in at least one of the preceding claims,

wherein the frequencies of the medium-frequency feed-ins have deviations around f_M.

6. A device for carrying out the method as recited in at least one of the preceding claims, the means for driving the respective switch including no means for synchronization to the medium-frequency feed-ins.

7. The device as recited in claim 6,

wherein the means for driving the respective switch include a modulator having rising and falling edges running in a linear fashion over time, the amount of the gradient of the rising and falling edges being selectable to be different.

8. The device as recited in at least one of claims 6 through 7,

wherein the modulator is a sawtooth voltage generator.

9. The device as recited in at least one of claims 6 through 8,

wherein a matching controller has a plurality of feed-ins which supply one rectifier each, whose output currents are each brought together via a link-circuit reactor, and a switch is series-connected in such a way that the link-circuit current is either supplied to a link-circuit capacitor buffering the output voltage U₌ of the matching controller, or is shunted upstream of this link-circuit capacitor, depending on the power demand of the consumer connected to the matching controller.

10. The device as recited in at least one of claims 6 through 9,

wherein to supply a consumer, the output voltages of two or more matching controllers are parallel-connected via diodes.