Topics covered by the Reliability Working Group include dynamic system modeling, grid codes/interconnection requirements as well as interconnection process and studies, interoperability of equipment and controls, system disturbances, system interactions, weak grids, low or zero inertia power systems, grid forming converters, and electrical system standards.
Members of the Reliability Working Group are encouraged to interact with one another via Groups.IO, an online discussion platform and community network. The ESIG Resource Library is also a valuable tool for those seeking information on Reliability, as well as other topics.
Links to both can be found below:
(Please note: only members of ESIG may participate in the Working/Users Groups. If you are interested in membership, please email us at info@esig.energy)
High Share of Inverter-Based Generation Task Force
The objective of this task force is to develop an understanding of system need and the options for stable operation of future power systems with a very high share of inverter-based generation like wind, solar and storage, and a roadmap for making the transition from the power system of today to a future one dominated by inverter-based generation, working with research organizations, OEMs, and system operators to build a consensus.
Current work underway includes:
- Next Step: Exploring needs and capabilities for integration of planning processes and studies
Completed work includes:
Task Force Lead: Julia Matevosyan, ESIG
Stability Project Team
Objective:
The objective of this PT is to identify stability issues related to major grids reaching high levels of IBR penetration. The effort is centered on stability issues that are substantively altered or aggravated by the differences between IBR and synchronous resources. The project team will investigate oscillations that have been observed or are anticipated in grids with IBR, and identify gaps in our understanding that should be addressed in future R&D efforts.
Approach:
There are broad systemic stability issues, such as small signal stability, first swing transient stability and voltage stability. The PT will start with consideration of the latest IEEE stability definitions, but not be unduly constrained by them. The participants will refine the current understanding with respect to high IBR systems. The PT will focus on the stability issues that are most impacted by high levels of IBR and of highest importance to the industry and FSOs.
Efforts will include investigation of stability margins, metrics and indicators of approach to stability limits. The G-PST Pillar 1 Tool Inventory will be used as a starting point in the identification of tools for analysis, root cause assessment, and planning functions.
Deliverables:
Deliverable will include a report summarizing the current experience, state-of-the-art understanding and gaps, and synopsis of available tools and techniques as a basis for future R&D. A Policy Brief summarizing the results for policy makers will be prepared, and a webinar summarizing the results for a technical audience will be presented.
Project Team Lead: Nick Miller, HickoryLedge LLC
Services Project Team
Objective:
The objective of this PT is to identify new services needed in a power system with high IBR.
Approach:
This work will combine learnings from two previous reports; the first is the G-PST Pilar 1 System Needs and Services for Systems with High IBR Penetration report; the second is ESIG’s Grid Forming Technology in Energy Systems Integration. The former work identified how system needs are changing with increasing penetration of IBRs and declining amounts of synchronous generation; ESIG’s report developed a framework for solving a “chicken and egg” problem involving deployment of new inverters with advance controls termed grid forming.
The framework will identify a target system (in terms of target IBR penetration) with target reliability, and operating parameters; determining needs of such systems, and formulating these needs as services that are either procured through markets or required through interconnection codes. Definitions of services and methodologies to identify amounts of each service that are needed will be developed. A test system(s) will be used to conduct a number of case studies to understand when existing services become insufficient and new services are needed, and how to specify these new services.
Deliverables:
A report summarizing the findings of this work and providing recommendations for the specification of new services and methodologies around determining service amounts will be prepared. A Policy Brief summarizing the results for policy makers will be prepared, and a webinar summarizing the results for a technical audience will be presented.
Project Team Lead: Deepak Ramasubramanian, EPRI
GFM Testing Project Team
A number of requirements for GFM capabilities have been defined with some requirements at a very high level e.g., HECO and UNIFI, while others are providing more detailed technical specifications e.g., NGESO in Great Britain in their grid code change GC0137. This project team will examine the question of how to test for such requirements and demonstrate expected performance. This project will demonstrate how to verify the expected performance from inverters with advanced controls for various high-level requirements that are being defined by the industry (using both frequency scans and time-domain characterization). The purpose of this project team is to provide more clarity to the industry on meaning of these requirements and behavior sought as well as provide some guidance on possible testing and verification procedures. It may also inform development of the future interconnection requirements for advanced inverter controls.
Project Team Lead: Shahil Shah, NREL