Recent Events Autumn 2022
Another gathering has occurred in mid-November 2022. The day started with a reference group meeting, followed by the Technical Progress Meeting (TMP). The main topics for the TMP meeting was the following:
- A status report on the SysOpt progress and with updated work plans
- An overview over publications through SysOpt in 2022 (see own post about this)
- Status on current and future employment for the initialization of WP3 and WP4.
- Progress update from the three Ph.D. students Emil (USN), Dany (USN), and Hugo (NTNU)
Summary of the Ph.D. presentations
Dany works with the thermomagnetic modeling of the synchronous generator. Goals this year is to have a ready model of the generator made in Ansys. Then next year will be to develop a capacity twin. Dany creates thermal maps of the machine. He shows the thermal maps for determining where the thermal limit lies when doing reactive boosting. Thermal limits change from the rotor to the stator when considering different time windows. He proposes boosting and emergency modes based on the temperature class limits. He encourages power plant designers to design machines more suitable for boosting reactive power.
Emil goes through the challenges and issues related to the efficiency of multi-machine systems. He shows efficiency curves for a one- and two-machine system and explains that the highest efficiency reactive power sharing is not always equal between the generating units. He proceeds to show the synchronous machine’s ability for reactive power support to the grid when the grid voltage is low and how this is compatible with boosting concept. Then a study case is shown with five machines connected to a small distribution system. He shows a method for coordinated reactive power control and how to improve the control design by utilizing reinforcement learning for higher overall efficiencies.
Hugo presents his implemented secondary voltage regulator (SVR), which, in a small system, achieves coordinated actions and online control of the reactive power dispatch. Further work will focus on the control infrastructure for real-time coordinated control based on secondary voltage regulation schemes suitable for the Nordic power grid. Optimal power flow studies will be included in the next iterations of the SVR. He shows the modeling of the SVR structure and how the SVR fits into the timescales (in minutes) instead of the primary voltage regulation (AVR), with seconds as time windows, to avoid conflict between the controller loops. Hugo mentions centralized and de-centralized modeling strategies. His results from the simulation study show that the system voltages stay more stable for any choice of the pilot bus compared to no SVR. In addition, the utilization of the reactive sources is improved.