Placeholder

TRANSMISSION OPERATIONS & PLANNING

Special Assessments for Power system analysis

Focusing on geomagnetic disturbance analysis, harmonic modeling, electromagnetic transient studies, and sub-synchronous oscillation analysis for transmission systems. 
 

Research and Development Challenges

Given the unprecedented changes in power systems driven by ascendance of large loads, inverter-based resources, power electronics-based transmission technologies, as well as increased vulnerabilities due to extreme events, transmission planners need to perform studies that are beyond traditional power flow and stability analyses. These studies, broadly referred to as "special studies", require tools, models and methods that are not commonly used by planners, and there is in general a lack of expertise in the industry. However, there is a growing need for performing these studies to ensure system reliability as well as ability to withstand extreme events.

In the years to come, we plan to:

  • Provide models, planner guidance (including AI use), and mitigation examples at grid and inverter plant levels; improve equipment models for harmonic studies.
  •  Issue AI guidelines for EMT modeling, screening tools with defaults, and capabilities for lightning/ switching and transformer inrush analysis; continue advancing EMT study tools.
  • Investigate small signal/impedance and eigenvalue-based methods; develop/maintain Impedance scanning tool [ZSCAN] (positive sequence and EMT), Signal Damping Analysis Tool (SDAT) for damping/modal analysis, and an impedance repository for Power electronics-based loads.

Related Projects

High-Impact, Low-Frequency (HILF) Analysis

EPRI continues to develop analytical tools and methods related to GMD vulnerability assessments to help transmission planners and operators to provide background knowledge and insights.

Transmission Harmonic Analysis

The goal is to provide recommend planning solutions at the grid and inverter-based generation levels, including examples using various harmonic mitigation techniques for transmission systems.

Electromagnetic Transient (EMT) Analysis

Develop practical guidelines, models, and methods to help planners with modeling of components, tuning of models to match measurements, analyses to perform, default parameters to use, and develop mitigation options in commercially available tools used by utilities.

Sub-Synchronous Oscillations (SSO) Analysis

Investigate use of small-signal stability analysis techniques, e.g., impedance-based and eigenvalue-based stability methods, and need for tools to study and evaluate controller interaction driven and resonance interaction driven stability aspects for grids with increasing levels of IBRs and other power-electronic based devices. Develop insights into identifying when oscillation would be an issue, whether it can be mitigated, and studied with the help of simulations. Establish an integrated risk assessment process to assess and mitigate risks for control interactions. This will provide transmission planners guidance on applying screening methods and screening metrics to make informed decisions on when detailed EMT domain simulations are required.

Related Deliverables

Modeling Transmission Equipment for Harmonic studies

3002032868

Presents a methodology for developing harmonic models for common transmission equipment.

AI for EMT Modeling

3002034148

Presents ideas and prototyping for an AI-powered assistant designed to streamline the development of EMTP® scripts.

Protection for SSO

3002032995

Describes protection options to reduce the risk or asset damage or system collapse due to SSO.

Pulsating AI Training Impact on Grid

3002034099

Examines the emerging risks associated with subsynchronous torsional interactions (SSTI) between turbine-generator shafts and the variable, high-power loads produced by AI data centers.

Area Leads