Grid Forming Tutorial

Lunch

Lecture 1 (45 min.)
Grid Forming Inverters: Modeling, analysis, and road to performance standardization
Deepak Ramasubramanian (EPRI, USA)

With many power systems around the world rapidly going towards high percentage of inverter based resources, the concept of grid forming will be important. This tutorial will provide a detailed discussion on the notion of grid forming and what it entails. It goes beyond the aspect of voltage source behind impedance and showcases the importance of hierarchy of control within an IBR plant. Delivery of services and focus on performance is stressed. Further, the tutorial will walk through details of developing simulation models and identification of grid forming property from these models. Finally, through the use of application examples, a preliminary road to standardization will be discussed.

Discussion &  Short Break (15 min)

Lecture 2 (45 min.)
Grid-Forming Plant Controls: Bridging the Gap between Components and Grid Code Compliance
Benjamin Joseph Braun (FluenceEnergy, Germany)

Recent updates to the grid codes of key markets enabling grid-forming operation on the public network have opened a multitude of new applications. This in turn has exposed a gap between components level controls and complete code compliant solutions.

Historically, GFM applications have been largely limited to industrial black-start and isolated electrical systems. Such projects have provided countless lessons and improvements, but to date no component level standards defining GFM controls have been defined. Validation and bench-marking of manufacturer’s and integrator’s GFM capabilities is thus difficult.

This tutorial will highlight the current variations in component level GFM controls while recommending minimum technical requirements and testing regimes to allow for fair comparisons of suppliers in lieu of standards. Additionally, the required plant level integration considerations and controls needed to convert components into solutions compliant with the latest grid codes will be highlighted.“

Discussion &  Short Break (15 min)

Coffee Break

Lecture 3 (45 min.)
Grid Forming Control – A TSO’s perspective
Georg Deiml and Sebastian Höhn (TenneT, Germany)

„Grid Forming Control – A TSO’s perspective”, addresses two principal aspects of grid forming control:
– At first, a detailed explanation and quantification of the system needs for grid forming control in the Continental European Synchronous Area is presented and discussed: the overall demand of instantaneous reserve and controller stability of power electronic dominated AC network.
– Secondly, TenneT’s strategy for specification, implementation and proof of system conformity for grid forming control is presented, illustrated by some real project examples from power electronic integration, i.e. STATCOMs, HVDC interconnectors, and DC connected power park modules.

Discussion &  Short Break (15 min)

Lecture 4 (45 min.)
Grid Forming Wind Turbines: Challenges and Opportunities
Inga Skrypalle (Vestas, Denmark)

With upcoming grid forming requirements around the world, but limited experience with application in wind power plants, wind turbine manufacturers face additional challenges specific to their product. Wind turbines with grid forming control have their mechanical components exposed to faults in the electrical grid, leading to impacts which can be difficult to quantify and mitigate. The tutorial will elaborate on the potential implications, how they could be addressed from a software & hardware design aspect, as well as how grid codes could accommodate and market schemes could support socio-economically reasonable implementations, serving the needs of the electrical system, while regarding physical limitations of different technologies.

Discussion & Closing (15 min)

Coffee Break

Lecture 5 (45 min.)
Comparison of Grid Forming Interconnection Requirements
Julia Matevosyan (ESIG, USA)

With grid forming controls being considered as one of the solutions for reliable integration of inverter-based resources (wind, solar, storage), there is a need to define interconnection requirements (or grid codes) and performance expectations for this technology. Around the world there is a handful of entities that has already started working on grid codes for grid forming technology, among those National Grid Electricity System Operator (NGESO) in Great Britain, Australian Energy and Markets Operator (AEMO) and ENTSO-E. North American Reliability Corporation has also developed a white paper listing out grid forming capabilities and how a utility or a system operator wanting to deploy this technology today should test for grid forming capabilities through simulations. This part of the tutorial will cover capabilities sought from grid forming inverter-based resources by the system operators and compare various existing or proposed requirements.

Discussion & Closing (15 min)