ATP/MODELS Differentiator-Smoother Filter Model Validated Using Actual Time-Domain Relay

Traveling wave (TW)-based algorithms have gained notoriety among protection solutions for transmission lines. As a result, fast and reliable techniques for detection of incident and reflected fault-induced wave fronts have been increasingly reported in the literature. There are many filter technologies used on TW-based applications and, amongst them, the differentiator-smoother filter (DS filter) has shown to be promising compared to another one. Based on that, aiming to apply a reliable DS filter model in Alternative Transients Program (ATP) simulations during the study of TW-based solutions, this paper demonstrates the DS filter implementation using the ATP/MODELS language from tests using actual SEL-T400L relays, where the DS filter is embedded, the proposed ATP/MODELS DS filter function is validated. The obtained results show that the time response of the proposed ATP/MODELS filter block is the same of the actual one available in SEL-T400L relays, thereby it can accurately emulate the relay DS filter response during ATP studies.