Transmission Planning and Integration of Inverter based resources

Models, tools and methods to ensure resilient, reliable and clean transmission networks.

Integrated Grid UNIFI Consortium PVMOD Transmission and substation

Research and Development Challenges

EPRI’s Transmission Planning research area supports the development and validation of planning study models, planning processes and frameworks, and reliability and resiliency assessment analytics. These are required to build a reliable, resilient, and economic transmission grid that integrates an evolving generation mix to supply an increasingly complex load, that can also act as a system resource.

Key areas of focus include

Modeling of emerging loads such as EV charging stations, data centers, hydrogen electrolyzer
Improvements to the composite load model and help utilities with development and adoption of the composite load model
Measurement-based load modeling approach and data collection
Aggregated DER model adoption, data aggregation approaches to develop the model, DER representation in transmission system in the context of FERC O2222 (jointly with P173A)
Modeling of HVDC controls for off-shore wind connection
Grid forming controls for HVDC
Refinements to generic models for FACTS and HVDC as needed
Improve the Resilient System Investment Framework (RSIF)
Improvements to the High Level Screening (HiLS) tool by incorporating DC powerflow feedback to cluster similar operational hours

Formalization and improvements to an automated powerflow case creation tool for representative hours selected from HiLS analysis.
Data analytics and outage statistics for transmission planning reliability studies
Support transmission planning as part of the comprehensive integrated planning analysis for assessing reliability of decarbonization pathways
Update coordinated expansion planning tools (JHSMINE and ACEP) for co-optimization
Offer topical webcasts and quick insights on existing issues
Maintain and enhance the GICHarm tool for harmonic compliance studies for TPL-007
Improve the B2E tool for converting magnetic fields to electric fields
Update GMD planning and operations guides

Enhance IBR harmonic models
Revise the IBR harmonic modeling and study guide
Develop a guide on flicker analysis in the presence of IBR
Work on TRV studies guide
Develop a tool to analyze lightning and switching transients
Create a guide on temporary overvoltage studies
Enhance the E-Energize tool for analyzing transients in transformer switching
Assess impedance-based and eigenvalue-based methods for small signal stability
Improve screening methods for SSO analysis
Develop guidelines for performing SSO analysis in EMT

Enhance the Advanced Reliability Toolset (ARTS)
Develop node-breaker models in planning cases using EMS data and topology mapping
Improve contingency screening algorithms for systems with high IBR penetration
Explore High Performance Computing (HPC) for reliability assessments
Provide guidelines on the impact of increasing HVDC links in transmission systems
Consider Multi Terminal DC (MTDC) grids in transmission planning
Assess HVDC for providing ancillary services
Update the HVDC planning guide
Enhance the Controlled Planning Framework (CPLANET) tool for integrating Grid Enhancing Technologies (GET)
Update the GET reference guide

Related Projects

System Planning Methods, Tools, and Analytics

This project set supports the reliable integration of inverter based and distributed energy resources in transmission planning and protection activities. The research effort develops models and tools for the assessment of onshore and offshore wind, PV, battery energy storage, hybrid plants, and DER in bulk system planning and protection studies. Updated versions of models and tools including short circuit modeling, weak grid analysis and tools, relay settings and grid forming convertors are delivered to members, resulting in reduced engineering time for studies as well as improved models and study tools to ensure bulk system reliability.

Model Development, Validation, and Management

This project set addresses the need to develop generic, publicly available models that accurately capture the aggregated dynamic response of loads, power electronic-based transmission technologies, as well as aggregated DER for dynamic studies. The research is performed in close collaboration with industry stakeholders – WECC, NERC, software vendors, and equipment vendors in addition to transmission planners

Special Assessments for Transmission Planning

This research addresses specific issues in the planning process beyond power flow and stability analyses to address challenges posed by ascendance of inverter-based resources, more power electronics-based transmission technologies, and increased vulnerabilities due to extreme events. This project set provides a repository of topics that includes geomagnetic disturbance analysis, harmonic modeling and analysis for transmission systems, electromagnetic transient modeling and studies, and modeling and analysis for sub-synchronous oscillations for transmission systems.

Analytics for Emerging Transmission Planning Needs

This project set focuses on developing new analytics using state-of-the-art approaches and data analytics to help planners save time and resources to make planning decisions. The topics include integration of Grid Enhancing Technologies (GET) in transmission, integration of HVDC technologies specially in the context of off-shore wind and remotely connected renewables, and tools for automated contingency generation and screening of a large number of contingencies for system reliability assessments.

System Planning Methods, Tools, and Analytics

Supports the integration of inverter-based and distributed energy resources in transmission planning and protection. It develops models and tools for assessing wind, PV, battery storage, hybrid plants, and DER in bulk system studies. Updated tools, including short circuit modeling, weak grid analysis, relay settings, and grid-forming converters, are provided to members, reducing engineering time and improving system reliability.