Research

In this paper, actual field data recorded from DFRs over a period of 14 months is analyzed to present and discuss the behavior of reactor switching due to inrush and other observed effects for different operating conditions. This paper has diverse, practical scenarios to offer in the form of waveforms during reactor energization which help understand and avoid misoperations.

In this paper, we present a framework for the automatic generation of coordinated relay settings for directional time overcurrent relays, which represents one of the most challenging coordination problems engineers face. Our framework extends existing approaches and increases the level of automation by seamlessly interacting with fault simulation software to both provide input to and verify the coordination results of pickup and time dial settings chosen by the setting generator.

Unique expertise will be crucial in putting together a process which power plant owners can easily implement and apply to meet the requirements for PRC-027-1. This is where automation tools like Settings Automation Relay Assistant (SARA) can help by streamlining the entire relay setting development process.

Accepted by IEEE. © 2018 IEEE

C. Thomas, J. Perez, L. Hankins and H. Tribur, "An innovative and automated solution for NERC PRC-027-1 compliance," 2018 71st Annual Conference for Protective Relay Engineers (CPRE), College Station, TX, USA, 2018, pp. 1-11.

doi: 10.1109/CPRE.2018.8349772

Compliance with NERC PRC-027-1 has brought increasing stress to utilities as they work to establish a defined process for performing relay setting development and coordination at regular intervals. While current software programs attempt to aid utilities in complying with this new standard, they only offer an overwhelming and unmanageable report of coordination study results. None of the current programs provides a work flow from relay setting development to wide area coordination, which is what utilities desperately need. In this paper, we present an innovative process to comply with the R1, R2, and R3 requirements of PRC-027-1 through the use of an automated solution.

This paper demonstrates a sophisticated solution that introduces engineers to an improved and more efficient relay setting development process. Using the latest software development tools, this new solution provides a more advanced method to calculate settings compared to existing methods, and provides an intelligent way to uniformly standardize relay setting templates, eliminate data transfer errors, and overall perform settings, peer-peer review processes and coordination studies at a fraction of the previous time.

In partnership with Cross Texas Transmission, this paper discusses the operation of two differential relays protection algorithms during a reactor inrush. Detail algorithm and waveform analysis of the Restrain and Operate current reveal the fundamental differences between the two relays.