Rise of the Grid-Forming Inverters

Image courtesy of Michael Kappel under Attribution-NonCommercial 2.0 Generic Deed, resized to 700 x 391 pixels.

Researchers at the Pacific Northwest National Laboratory (PNNL) have recently modeled how grid-forming inverters can provide a boost to grid stability and reliability.  This technology is especially useful given the rise in demand coming from data centers and general electrification, as well as the increased integration of renewable energy sources, microgrids, energy storage technologies and distributed energy resources (DERs) into a more decentralized grid.

In a nutshell, a grid-forming inverter is designed to control voltage instead of current, whereas the traditional inverters currently in use focus on controlling the current.  Let’s take a closer look at how this works.

Benefits of Grid-Forming Inverters

Unlike traditional inverters, which typically operate by synchronizing with an existing grid (i.e., grid-following inverters), the grid-forming variety can create and maintain a stable voltage and frequency in an electrical network, effectively ?forming? the grid.

Some key features & benefits of this technology include:

• The ability to establish voltage and frequency, which helps maintain grid stability even when traditional generation sources (like fossil fuels) are offline or when operating in isolated or islanded modes.
• The ability to facilitate a ?black start,? which helps outage restoration because they can start up and establish a grid without needing an external power source.
• The ability to streamline the integration of renewable energy sources as well as microgrids into the grid by managing the variability and intermittency of these energy sources.

Many industry groups have analyzed this technology and believe it is necessary to maintain reliability going forward.  In addition to PNL, Western Electricity Coordinating Council (WECC), the Electric Reliability Council of Texas (ERCOT), Midcontinent Independent System Operator (MISO), The North American Electric Reliability Corporation (NERC), the DOE Solar Energy Technologies Office (SETO), and others have been involved with investigating and developing a framework for the technology, and all agree that it’s a must-have.

In the final analysis, grid-forming inverters represent an important and likely necessary technological advancement as it relates to the evolution of the power grid.