Taku Noda
The International Conference on Power Systems Transients (IPST) was held in Thessaloniki, Greece, on 11–15 June 2023 (Figure 1). This biennial event offers a platform for the exchange of scientific and technical information related to electromagnetic transients (EMTs) occurring in electric power systems. It started in 1995, in Lisbon, Portugal, and the 2023 conference was the 15th edition. Counting its predecessor, the 1993 European Conference on Power Systems Transients, the conference has 30 years of history. With the rising importance of EMT technologies for the integration of power electronics-based systems into power systems, the conference is considered a premier event in this field of research. The decision that all papers presented at the conference would be included in Electric Power Systems Research (EPSR) added further value to the event. Before talking about the technical aspects of the conference, this writer would like to start with the social aspect, which may well characterize the conference’s atmosphere.
Figure 1. IPST 2023 participants gather at the Porto Palace Hotel.
The conference was really well organized, and various social events were arranged so that new participants could easily get into circles of EMT people. As usual, the welcome reception (Figure 2) was arranged for the day before the first day, and a Thessaloniki guided tour was arranged for the late afternoon of the first day. This is actually very important. When you have a seat on a bus during a tour, I am pretty sure you will talk to the person sitting next to you. This is a good chance for a new participant to get acquainted with people (Figure 3). On the second day, a banquet dinner was arranged in a large restaurant on a hill (Figure 4). The restaurant had a large room where the participants enjoyed dinner and dancing. It also had a large lawn where the participants were able to enjoy talking, with beautiful and refreshing air and scenery (Figure 5). On the third day, the participants were able to choose a visit to the Vergina archaeological site or Gerovassiliou winery. Together with the atmosphere of the conference venue, the Porto Palace Hotel, which has a historic large room for lunches and coffee breaks, the event was quite impressive as the first postpandemic IPST. I would like to mention that this precisely designed conference was organized by Prof. Grigoris Papagiannis and Prof. Theofilos Papadopoulos in the tradition of Prof. Maria Teresa Correia de Barros, who began IPST. I am sure this conference has become an unforgettable memory for each participant, and this conference reminds me that getting acquainted with people is the most important function of conferences.
Figure 2. A large hall at the venue hosts the welcome reception, coffee break discussions, and lunches that include sponsor booths.
Figure 3. Participants get acquainted at various events.
Figure 4. IPST 2023 includes a banquet dinner followed by dancing.
Figure 5. Participants mingle on the lawn of the banquet dinner restaurant.
Figure 6. Participants attend technical sessions.
Gathering about 200 EMT experts from around the world, solutions for up-to-date and long-standing issues were presented and discussed during the conference. In the past, EMT technologies were used for the simulation of overvoltages, inrush currents, and abnormal oscillations occurring in power systems, facilitating design and operation. They are part of conventional power engineering. But we are now also working for carbon neutrality. Most renewable energy generation systems, such as photovoltaic and wind, are integrated into the power system by using power electronics converters. Battery energy storage systems, including electric vehicles, also use power electronics converters for their interconnection. As you probably know, “power electronics” is the key term for developing and understanding power systems today. For the design and operation of power electronics-based systems, which control electrical power through high-speed switching by semiconductor devices, waveform-level, that is, EMT, simulations are inevitable. EMT simulation is able to give waveform-level results that cannot be obtained by traditional phasor-based simulations. This is the reason for the recent progress of EMT simulations. Beyond interconnection, power electronics technologies are used for distant and submarine power transmission, known as high-voltage dc transmission (HVDC). The wide penetration of renewable energy generation systems, which use power electronics converters for integration into power systems, rapidly reduces the inertia of power systems. To keep the systems stable, the concept of grid-forming (GFM) inverters together with grid-following inverters (GFL) is quite important. Again, this technology uses power electronics. In the past, power electronics converters were used for supplementary control of power systems, and this technology is known as flexible ac transmission systems (FACTS). But the recent penetration of renewable energy generation systems has changed the situation. Now the concept of GFM inverters, or “power electronics,” plays a key role in the system, and EMT simulations play a key role in power engineering. It was quite impressive to see that many papers discussed these issues. New simulation methods combining EMT and phasor simulations to deal with a large-scale power system were also proposed. For the same purpose, some authors tried to use very fast parallel computers to deal with a large-scale power system, only with an EMT simulation method. Furthermore, some authors proposed sophisticated eigenvalue and frequency response approaches to assess waveform-level stability in a mathematical way. It should be noted that real-time simulators play very important roles for the development and commissioning of power electronics-based systems. Of course, papers on traditional EMT issues, such as line, cable, transformer, and generator modeling; overvoltage and inrush current simulations; protection relay developments; and power quality problems, were presented and discussed (Figure 6). For this conference, Prof. Chul-Hwan Kim and this writer cochaired the technical committee. Here, we unfortunately must mention sad news: during the past two years, our dear friends on the IPST Steering Committee Prof. Akihiro Ametani and Laszlo Prikler passed away, and we had a session to review their achievements in a relay form during the opening ceremony.
In this changing world, it was quite meaningful that about 200 EMT experts gathered in one place to talk about our current developments, problems, and future since EMT simulations play an inevitable role to integrate, transmit, and stabilize renewable energy using power electronics. In the 1980s and 1990s, different EMT tools were created, and groups formed around them. Engineers belonging to different groups did not exchange knowledge. This was the motivation to create IPST. Now we have several EMT tools available, and we are able to exchange our information and thoughts thanks to IPST. The memory of Thessaloniki will be engraved in the hearts of EMT experts, and IPST will continue offering a platform for the exchange of scientific and technical information related to EMTs in electric power systems.
Check for the latest information about IPST at its website, https://www.ipstconf.org/. All papers presented at past IPST conferences can be viewed and downloaded from the website. For the papers presented at IPST 2023, a special issue is planned in EPSR. The next IPST will be in Guadalajara, Mexico, in 2025.
Digital Object Identifier 10.1109/MELE.2023.3320556
2325-5897/23©2023IEEE