Fault current limiting system and method
AssigneeABB Technology AG
InventorsCarlo Gemme, Richard Tinggren, Karl-Heinz Hartung, Lars Liljestrand
Life of this patent
Estimating the term…
Abstract
A fault current limiting system includes switching means for providing a fast switching operation; a parallel current path comprising a limiting fuse; and a switching system to automatically replace a blown set of fuses with an unblown set of fuses after a fault current limiting operation has occurred. A method of limiting fault current includes providing a fast switching operation; providing a parallel current path comprising a limiting fuse; and automatically replacing a blown set of fuses with an unblown set of fuses after a fault current limiting operation has occurred.
Claims11
A fault current limiting system, the system comprising:
- switching means, which are connected to a circuit breaker for managing a current breaking operation on a power distribution line in absence of fault, said switching means providing a fast switching operation;
- a current path comprising at least a limiting fuse, said path being arranged in parallel to said switching means;
- a switching system to replace a blown set of fuses with an unblown set of fuses after a fault limiting operation has occurred;
- a control unit, which receives signals indicative of starting fault conditions, said control unit estimating the amplitude of the fault current based on said signals, said control unit sending a switch command to the switching means and to the circuit breaker when the fault current is estimated to rise above a predefined threshold,
- said control unit sending a switch command only to the circuit breaker when the fault current is estimated to remain under said predefined threshold.
A method for limiting fault current, the method comprising the following steps:
- providing a current breaking operation on a power distribution line in absence of fault;
- providing a fast switching operation responsive to a fault;
- providing a current path comprising at least a limiting fuse arranged parallel to a fast switching operation path;
- automatically replacing a blown set of fuses with an unblown set of fuses responsive to a fault limiting operation;
- receiving signals indicative of starting fault conditions in a control unit;
- estimating an amplitude of a fault current based on said received signals,
- when the fault current is estimated to rise above a predefined threshold, sending a first switching command from the control unit to effect both the fast switching operation and the current breaking operation, and
- when the fault current is estimated to remain under said predefined threshold, sending another switching command from the control unit to effect only the current breaking operation.
A fault current limiting system, the system comprising:
- a fast switch device capable of providing a fast switching operation;
- a circuit breaker connected to the fast switch device, said circuit breaker controlling a current breaking operation on a power distribution line in absence of fault;
- a current path comprising at least a limiting fuse, said current path being arranged in parallel to said fast switch device;
- a fuse revolver switch that automatically replaces a blown set of fuses with an unblown set of fuses responsive to detection of a fault condition;
- a control unit operably connected to receive signals indicative of a fault condition, said control unit estimating an amplitude of the fault current,
- wherein, responsive to said fault condition, said control unit sends a switch command to both the fast switch device and to the circuit breaker when the fault current is estimated to rise above a predefined threshold,
- wherein said control unit sends a switch command only to the circuit breaker when the fault current is estimated to remain under said predefined threshold.
Dependencies are inferred from the claim text.