System-Wide Dynamic Protection Settings For Transmission Systems

Modern power transmission systems are undergoing significant changes, including the integration of large-scale Inverter Based Resources (IBRs), the retirement of conventional generation, and the re-building and re-routing of transmission lines to accommodate increasing demand and new load. These modifications often call for planned outages of existing primary system equipment to facilitate new construction. This situation leaves protection engineers with some critical questions to address: Does the system protection perform as expected under various system configurations or during periods of variability due to intermittent renewable generation? If not, what modifications are required for specific protection relays or setting philosophies to restore optimal performance? Addressing these complex questions can be a daunting task for already overburdened system protection departments.

This paper explores methods to efficiently assess the behavior of overcurrent and impedance-based protection elements across an area or an entire system to ensure their performance. After outlining the methodology, we will discuss several valuable use cases:

• Outage Configuration Testing: Evaluating outage configurations to determine impacts on clearing times and identify high-risk elements for further assessment. This enables dynamic adjustments to settings based on system topology to maintain performance. • Setting Philosophy Evaluation: Assessing various setting philosophies to determine the best approach for specific systems or areas, especially in regions with high IBR penetration. This includes a detailed example of how LUMA Energy applied this methodology to analyze system-wide protection performance data and enhance their Ground Time Overcurrent protection philosophy. • Relay Performance Verification: Quickly identifying at-risk protection elements for further investigation and/or prioritized updates to the latest protection philosophy.

In the ever-evolving landscape of modern transmission systems, protection engineers must adapt to rapid changes. This paper presents methodologies to help engineers stay ahead in maintaining effective performance of system protection.