Tech
Test procedure developed for gridforming inverters
In addition to expanding renewable energy generation, a successful energy transition requires stable system operation at all times. To achieve this, renewable energies and storage power plants will have to take on extensive system services and essential grid-forming properties in the future.
In the “GFM Benchmark” project, Fraunhofer ISE developed a test procedure for grid-forming inverters on behalf of the four German transmission system operators and applied it to devices from various manufacturers. On the one hand, the project provided a comprehensive overview of the market readiness of grid-forming inverters.
On the other hand, the project results provide an important practical check for new national and European testing standards.
The fully integrated grid components with grid-forming properties planned by the transmission system operators will not be able to fully meet the demand for grid-forming power. Therefore, customer systems must also contribute to stabilizing the power grid: They should behave in a grid-forming manner, i.e., contribute to providing a grid voltage with stable amplitude and frequency.
But what exactly does that mean? In recent years, many scientific studies and publications have been produced on this topic, and some countries have grid operator documents that describe grid-forming behavior. However, there is no uniform standardization or definition, which leaves room for interpretation.
Therefore, in the first step of the project, the Fraunhofer ISE team worked with the grid operators 50Hertz Transmission GmbH, Transnet BW GmbH, Amprion GmbH, and Tennet TSO GmbH to develop a measurement and evaluation procedure for the stabilizing properties of inverters, incorporating findings from both grid operation and research.
Major differences in grid-forming behavior
“We wanted to see what manufacturers understand by grid formation and how they implement this in the programming of their devices,” explains department head Dr. Sönke Rogalla from Fraunhofer ISE. “So we invited them to put their devices to the test in our laboratory.”
Seven companies responded to the call and had their storage inverters, which cover a power range from a few kilowatts to five megawatts, measured according to the new test procedure. They came from different countries and were at different technology readiness levels, from pilot to prototype to series production.
The researchers used the tests to investigate the differences between the devices in terms of grid formation by exposing them to various operating conditions in the laboratory. In addition to normal operation, critical grid situations such as rapid frequency changes, short circuits, and phase jumps were simulated.
“The devices exhibited similar behavior under clearly defined requirements. In other cases, however, there were major differences, and we were able to provide the manufacturers with suggestions for optimization for almost every device,” explains project manager Roland Singer from Fraunhofer ISE. The willingness and commitment of manufacturers to advance the development of grid-forming inverters is high.
Proven verification methods are essential for market launch
At the same time, the project provided relevant practical experience in testing grid-forming inverters and optimized the test procedures. Important findings were incorporated into the ongoing standardization work at the European level even during the project phase. The Fraunhofer ISE team contributed its expertise to the creation of the VDE FNN note “Grid-forming properties.”
The recently published document describes the requirements and verification procedures for grid-forming units. It forms the normative basis for participation in the future market for instantaneous reserve, which will start at the beginning of 2026 and represents an additional interesting remuneration path, especially for battery storage systems.
With its experience in the “GFM Benchmark” project, the team at Fraunhofer ISE is ideally positioned to support manufacturers and users of grid-forming units with certification measurements in accordance with the FNN note. Standardization work at the European level is also progressing. ENTSO-E, the network of European transmission system operators, is working on an implementation guide with comprehensive grid-forming requirements, which should facilitate the transition to national regulations.
Provided by
Fraunhofer ISE
Citation:
Test procedure developed for gridforming inverters (2025, September 4)
retrieved 4 September 2025
from https://techxplore.com/news/2025-09-procedure-gridforming-inverters.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.
Tech
‘STAGED’: Conspiracy Theories Are Everywhere Following White House Correspondents’ Dinner Shooting
In the immediate aftermath of the attack on the White House Correspondents’ Dinner on Saturday night, influencers, pundits, and random posters lit up social media platforms like X, Bluesky, and Instagram with conspiracy theories about the attack and the alleged shooter.
Both left and right-wing accounts claimed, without evidence, that the attack was staged.
President Donald Trump, Vice President JD Vance, and dozens of other high-profile administration officials and journalists were attending the dinner at the Hilton hotel in Washington, DC, when a suspect, later identified by media reports as Cole Tomas Allen from California, allegedly ran past security towards the event. He was detained by law enforcement while the president and vice president were evacuated. Police said that they believe Cole acted alone, but did not expand on who his intended target was or what his motive may have been. “We believe the suspect was targeting administration officials,” acting attorney general Todd Blanche told NBC’s Meet the Press on Sunday morning.
On Bluesky, which has a predominantly left-leaning user base, many people simply wrote the word “STAGED” over and over again, echoing the response to the Trump assassination attempt in Butler, Pennsylvania in 2024.
On X, many claimed the shooting was staged as a way to bolster support for Trump’s plan to build a new ballroom in the White House. The president referenced the ballroom in a press conference after the incident and a Truth Social post on Sunday morning. Many prominent online Trump boosters echoed the need for the ballroom, including far-right podcaster Jack Posobiec, Libs of TikTok creator Chaya Raichik, and Tom Fitton, the right-wing activist who runs Judicial Watch.
Their quick response, conspiracy theorists claimed, was evidence of a coordinated campaign following the shooting. “Is this another staged event,” one X user asked in a post that has been viewed more than 5 million times.
Other social media users who claimed the incident was staged pointed to a Fox News clip that featured the station’s White House correspondent Aishah Hasnie speaking from the Hilton hotel. Hasnie told viewers that prior to the shooting, press secretary Karoline Leavitt’s husband allegedly told her “you need to be very safe,” before the call was cut off.
“Fox News just cut one of their reporters off as they seemed to indicate the shooting was a pre-planned false flag,” one X user wrote in a post that has been viewed more than 2 million times. Hasnie later clarified in an X post that her cell service had cut out in a location with notoriously bad service, adding: “He was telling me to be careful with my own safety because the world is crazy. He was expressing his concern for my safety.”
“I don’t want to be fomenting conspiracies,” wrote Angelo Carusone, the chair and president of Media Matters, on Bluesky about the Fox News interview. “But I mean…this was super weird. Super weird.”
Leavitt herself was also the focus of conspiracy theories after she said “shots will be fired” in an interview ahead of the dinner, referring to the jokes Trump was scheduled to deliver. Following the attack, X users claimed the comment was “strange,” “sus,” or a “curious choice of words,” while sharing memes that suggested the shooting was staged. At least one mainstream outlet appeared to amplify the conspiracy theory as well, describing Leavitt’s comment as “eerie” and “bizarre.”
Tech
Your Kindle Is Better With Accessories. Here’s Where to Start
Kindle Holders
Hate holding up your Kindle? Or struggle with chronic pain that makes holding it feel terrible? These holders will literally take the weight out of your hands.
A Freestanding Charger
Looking to keep your Kindle charged without adding another cord to the floor of your desk or bedside table? Same. Here’s a more stylish solution if you have one of the Signature editions.
A Kindle Page Turner
The hottest new item to get as a Kindle lover is a page turner. They’re especially handy for holders like the ones above, where your hands aren’t already on the device, and can make for a great accessibility accessory for readers with different needs.
My biggest irritation with these devices so far is that you have to charge them both individually, and if one runs out of battery, the whole thing is useless. I also don’t love that the turner does tend to block at least one letter while I read, and you can’t place it on the lower or upper margins since it’ll activate the menus instead of turning the page. Still, it makes reading ultra comfortable, especially for my strained wrists.
Here’s my favorite one so far, that’s been solid at holding a charge, and next I’m testing this remote ($15) with a wearable ring clicker instead of a remote.
Tech
California Engineer Identified in Suspected Shooting at White House Correspondents’ Dinner
A 31-year-old engineer and computer scientist was identified by media reports and President Donald Trump as the suspected shooter at the White House Correspondents Dinner on Saturday night.
Cole Tomas Allen, of Torrance, California, was apprehended following the firing of shots at the Washington Hilton, where Trump was scheduled to deliver remarks to a ballroom full of journalists, cabinet officials, and Hilton staff. Allen’s name surfaced in media reports shortly before Trump posted two photos of a suspect following his apprehension. The person in the photos Trump posted matches photos of Allen.
In dramatic scenes, several shots were heard outside the ballroom, after which Trump and Vice President JD Vance were immediately rushed off the stage by the United States Secret Service. In the immediate aftermath of the shooting incident, it briefly appeared as if the event would proceed—Trump posted “LET THE SHOW GO ON” on Truth Social—but the event was eventually shut down.
According to the Metropolitan Police Department, the suspect “charged” a Secret Service checkpoint at the Hilton hotel, and was intercepted by agents. MPD interim chief Jeffery Carroll said the suspect was carrying a “shotgun, handgun, and multiple knives.”
At a White House press conference following the shooting, Trump said one United States Secret Service agent was shot but saved from serious injury by his bulletproof vest. Trump said the agent, who was not named, is “doing great” and in “great shape.” No other injuries were immediately reported.
The suspect was later transported to a local hospital “to be evaluated,” according to Carroll, who said he appears to be a “lone actor.”
Around the time Trump’s press conference began on Saturday night, he posted a picture on his Truth Social account appearing to show the suspected shooter on the ground, with his hands restrained behind his back, and a foil warming blanket covering the lower half of his body.
A WIRED review of public databases shows a seemingly minimal online presence associated with Allen’s name. According to his LinkedIn profile, he graduated from Caltech in 2017 with a bachelor’s in mechanical engineering and from California State University Dominguez Hills in 2025 with a master’s in computer science. An apparent photo of Allen that appears on Caltech’s website identifies him as a member of the school’s Mechanical Engineering 72 class, described by the school as a “two-term engineering design lab” for building robots and autonomous vehicles. His name is also listed in a 2025 Dominguez Hills graduation program. A search in a public facial recognition database returns only two images, both apparently of him as an undergraduate.
According to the alleged shooter’s LinkedIn profile, he has been employed part-time since March 2020 at C2 Education, a private company that helps students prepare for the SAT and ACT exams. In December 2024, C2 Education said in posts on LinkedIn and Facebook that he was the company’s “December Teacher of the Month.”
Since 2018, the suspected shooter has self-identified on his LinkedIn profile as a “self-employed” indie game developer. He appears to have released an “atomic fighting game” called Bohrdom on Steam in 2018. The game was advertised using accounts on YouTube and X that appeared to have little to no following. The caption for a trailer of the game describes it as a “non-violent, skill-based, asymmetrical fighting game loosely based on a chemistry model that is itself loosely based on reality.”
C2 Education and did not immediately respond to requests for comment. When reached for comment, the Metropolitan Police Department referred WIRED to a video of its public press conference.
-
Sports1 week agoWWE WrestleMania 42 Night 2: Live match results and analysis
-
Sports1 week agoNCAA men’s gymnastics championship: All-time winners list
-
Fashion1 week agoUK’s Sosandar returns to profitability amid robust FY26 performance
-
Entertainment1 week agoRuby Rose old essay resurfaces detailing night of alleged Katy Perry assault
-
Politics6 days agoUK’s Starmer seeks to deflect blame over Mandelson appointment
-
Entertainment6 days agoLee Anderson, Zarah Sultana kicked out of UK Parliament for calling PM ‘liar’
-
Entertainment1 week agoNathalie Baye, low-key legend of French cinema, dies aged 77
-
Business1 week agoNo fuel shortage: Govt assures 100% domestic LPG, PNG, CNG supply amid Hormuz energy crunch – The Times of India

