Current limiting circuit for limiting the magnitude of an alternating current
AssigneeSiemens Energy Global GmbH & Co. KG
InventorsMichael Beck, German Kuhn, Priyanka Gugale, Juan Pablo Ricon Castejon, Kunal Sharma
Life of this patent
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Abstract
A current-limiting circuit for limiting the magnitude of an alternating current. The circuit includes a coil unit and a capacitor unit, which are connected electrically in series, and a bypass device for electrically bridging the capacitor unit on occasion of an overcurrent. The bypass device has a first bypass branch and a second bypass branch connected electrically in parallel with the first bypass branch. A third bypass branch is connected electrically in parallel with a second bypass element of the second bypass branch.
Claims20
A current-limiting circuit for limiting a magnitude of an alternating current, the current-limiting circuit comprising:
- a coil unit and a capacitor unit that are connected electrically in series;
- and
- a bypass device connected for electrically bypassing said capacitor unit when an overcurrent occurs;
- said bypass device having a first bypass branch for bypassing said capacitor unit, a second bypass branch for bypassing said capacitor unit connected electrically in parallel with said first bypass branch, and a third bypass branch;
- said first bypass branch including a first bypass element, said second bypass branch including a second bypass element, and said third bypass branch including a third bypass element;
- and
- said third bypass branch being connected electrically in parallel with said second bypass element for bypassing said second bypass element.
A current-limiting circuit for limiting a magnitude of an alternating current, the current-limiting circuit comprising:
- a coil unit and a capacitor unit that are connected electrically in series;
- and
- a bypass device connected for electrically bypassing said capacitor unit when an overcurrent occurs;
- said bypass device having a first bypass branch for bypassing said capacitor unit, said first bypass branch including a first bypass element;
- said bypass device having a second bypass branch for bypassing said capacitor unit, said second bypass branch being connected electrically in parallel with said first bypass branch, and said second bypass branch including a second bypass element;
- a control unit configured to generate a first bypass signal when the electrical current flowing through said coil unit exceeds a first threshold value, wherein the first bypass signal causes said first bypass element to close;
- wherein said control unit is configured to generate the first bypass signal even when the electrical current flowing through a surge limiter of said capacitor unit exceeds a second threshold value.
A current-limiting circuit for limiting a magnitude of an alternating current, the current-limiting circuit comprising:
- a coil unit and a capacitor unit that are connected electrically in series;
- and
- a bypass device connected for electrically bypassing said capacitor unit when an overcurrent occurs;
- said bypass device having a first bypass branch for bypassing said capacitor unit, said first bypass branch including a first bypass element;
- said bypass device having a second bypass branch for bypassing said capacitor unit, said second bypass branch being connected electrically in parallel with said first bypass branch, and said second bypass branch including a second bypass element;
- a control unit configured to generate a first bypass signal when the electrical current flowing through said coil unit exceeds a first threshold value, wherein the first bypass signal causes said first bypass element to close;
- wherein said control unit is configured to generate a second bypass signal causing said second bypass element to close when said first bypass element does not close in response to the first bypass signal.
A method of limiting a magnitude of an alternating current, the method comprising:
- conducting the alternating current through an electrical series circuit of a coil unit and a capacitor unit;
- limiting the magnitude of the alternating current by electrically bypassing the capacitor unit to thereby increase an inductive reactance of the series circuit;
- bypassing the capacitor unit by way of a second bypass branch when a fault occurs during the bypassing of the capacitor unit by way of a first bypass branch, wherein the second bypass branch has a second bypass element;
- in addition to bypassing the capacitor unit by way of the first bypass branch or by way of the second bypass branch, electrically bypassing the second bypass element by way of a third bypass branch, which is connected electrically in parallel with the second bypass element and which has a third bypass element.
A method of limiting a magnitude of an alternating current, the method comprising:
- conducting the alternating current through an electrical series circuit of a coil unit and a capacitor unit;
- limiting the magnitude of the alternating current by electrically bypassing the capacitor unit to thereby increase an inductive reactance of the series circuit;
- monitoring respective currents flowing through two parallel-connected electrical coils of the coil unit;
- and
- generating an alarm signal as soon as a ratio of the currents flowing through the two electrical coils of the coil unit changes by more than a threshold value.
Dependencies are inferred from the claim text.