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Advanced Protective Relaying Technologies and Tools


a.      Advanced Protective Relaying Technologies and Tools

The reliability of an electric transmission or distribution system in response to a fault is heavily dependent upon the underlying protection scheme that is being utilized to identify and respond to that fault. The equipment that forms the basis of these schemes include:


·         Protective relays which respond to electrical quantities,

·         Communications systems necessary for correct operation of protective functions,

·         Voltage and current sensing devices providing inputs to protective relays,

·         Station dc supply associated with protective functions (including station batteries, battery chargers, and non-battery-based dc supply), and

·         Control circuitry associated with protective functions through the trip coil(s) of the circuit breakers or other interrupting devices.


Innovative advancements in protective relaying systems are almost limitless, which is why this topic area is focused more on reducing or eliminating those aspects that inhibit the performance and reliability of the elements in this field while improving the resiliency of such elements. Examples of such innovation include but are not limited to: Dynamic, adaptive or setting-less relays; Distinguishing between momentary and permanent faults; Misoperation reduction; and hidden failures. Collaboration with protection device manufacturers and utility protection engineers is strongly encouraged.


Questions – Contact: David Howard,

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