Method for protecting at least one consumer against overvoltage tages and device for carrying out the method

• US 7,057,869 B2
• Filed: 11/10/2001
• Issued: 06/06/2006
• Est. Priority Date: 12/01/2000
• 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: Kollar, Hans-Jürgen
• Primary Examiner(s): Jackson, Stephen W.
• Application Number:
  US10/433,345
• Publication Number:
  US 20040022002A1
• Time in Patent Office: 1,669 Days
• Field of Search: 361/91.1, 361/62
• US Class Current: 361/91.1
• CPC Class Codes: H02H 9/041 using a short-circuiting device
• CPC Class Codes: H02J 50/10 using inductive coupling
• 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

Abstract

A method and a device for protecting at least one consumer against overvoltages when working with 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 the 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 is fed from a medium-frequency current source with a medium-frequency current that is constant in its effective value during the power transmission; the respective consumer is supplied with energy by at least one matching controller having at least one feed-in; one or more fed currents are rectified in each instance in a rectifier, smoothed in each instance by a link-circuit reactor and brought together; with the aid of a switch, the link-circuit current, brought together in each instance, is either supplied to a link-circuit capacitor buffering output voltage U₌ of the matching controller, or is shunted upstream of the link-circuit capacitor, depending upon the power demand of the consumers; and the voltage U₌ at at least one link-circuit capacitor is compared to a predefinable value, and if this value is exceeded, an electronic power circuit-breaker is turned on for shunting the link-circuit current.

Claims

1. A method for protecting at least one consumer against overvoltages, comprising:

non-contactly transmitting electric power from at least one medium-frequency current source having frequencies that deviate around medium frequency to at least one moving consumer via at least one transmission line and transformer head allocated to the consumers and including a downstream matching controller configured to adjust power received from the transmission line;

supplying a transmission line from a medium-frequency current source with a medium-frequency current constant in an effective value during power transmission;

supplying a respective consumer with energy by at least one matching controller including at least one feed-in;

rectifying at least one fed current in a rectifier;

smoothing the at least one fed current by a link-circuit reactor;

bringing together the at least one fed current to form a link-circuit current;

one of supplying the link-circuit current to a link-circuit capacitor buffering an output voltage of the matching controller and shunting the link-circuit current upstream of the link-circuit capacitor in accordance with a power demand of the consumers and in accordance with a switch;

comparing the output voltage at at least one link-circuit capacitor to one of a fixed and a predefinable value; and

turning on an electronic power circuit-breaker to shunt the link-circuit current in accordance with the output voltage exceeding the on of th fixed and the predefinabl value.

2. The method according to claim 1, wherein the electronic pow r circuit-breaker includes a thyristor blocked, after firing, one of only after a drop below a holding current and upon disappearance of the current shunted therethrough.

3. The method according to claim 2, further comprising applying an alternating component of a voltage at the thyristor that does not reach a high critical value of voltage change per time so that firing of the thyristor is triggered by the alternating component.

4. The method according to claim 1, wherein the current smoothed by the link-circuit reactor does not have a high critical value of current change per time so that firing of a thyristor of the electronic power circuit-breaker is triggered by an alternating component of the current.

5. The method according to claim 1, wherein a voltage at the switch includes an alternating component higher than a critical value of voltage change per time that would trigger firing of a thyristor of the electronic power circuit-breaker if applied to the thyristor.

6. The method according to claim 1, further comprising decoupling an alternating component of a voltage applied at the switch so that at a voltage change per time at a thyristor of the electronic power circuit-breaker does not reach a critical values that firing of the thyristor is triggered.

7. The method according to claim 1, further comprising supplying signal electronics configured to generate a driving signal for the electronic power circuit-breaker from the voltage at the link-circuit capacitor.

8. The method according to claim 7, wherein the signal electronics include a positive feedback arrangement.

9. A d vice, comprising:

an arrangement configured to perform a method for protecting at least one consumer against overvoltages, the method including;

non-contactly transmitting electric power from at least one medium-frequency current source having frequencies that deviate around medium frequency to at least one moving consumer via at least one transmission line and transformer head allocated to the consumers and including a downstream matching controller configured to adjust power received from the transmission line;

supplying a transmission line from a medium-frequency current source with a medium-frequency current constant in an effective value during power transmission;

supplying a respective consumer with energy by at least one matching controller including at least one feed-in;

rectifying at least one fed current in a rectifier;

smoothing the at least one fed current by a link-circuit reactor;

bringing together the at least one fed current to form a link-circuit current;

one of supplying the link-circuit current to a link-circuit capacitor buffering on output voltage of the matching controller and shunting the link-circuit current upstream of the link-circuit capacitor in accordance with a power demand of the consumers and in accordance with a switch;

comparing the output voltage at at least one link-circuit capacitor to a fixed and a predefinable value; and

turning on an electronic power circuit-breaker to shunt the link-circuit current in accordance with the output voltage exceeding the one of the fixed and the predefinabl valu;

wherein the matching controller includes a circuit configured to protect against overvoltages at the link-circuit capacitor, the circuit including at least one electronic power circuit-breaker configured to shunt, in a conductive state, link-circuit current from the at least one link-circuit reactor upstream of at least one of the link-circuit capacitor and a decoupling diode.

10. The device according to claim 9, wherein the at least one link-circuit reactor is connected to the link-circuit capacitor via the diode.

11. The device according to claim 9, wherein the electronic power circuit-breaker includes a thyristor arranged to be blocked after firing only upon disappearance of current shunted therethrough.

12. The device according to claim 11, wherein an anode voltage of the thyristor corresponds to a maximum from voltage at the link-circuit capacitor and voltage at the switch.

13. The device according to claim 12, wherein an anode of the thyristor is connected to the at least one link-circuit reactor via a diode.

14. The device according to claim 12, wherein an anode of the thyristor is connected to the link-circuit capacitor via a resistor.