Adaptive Multi-scale Transient Modeling and Efficient Simulation of Wide-area AC/DC Power Systems

• Applicant: Professor Dr.-Ing. Kai Strunz
• Subject Area: Electrical Energy Systems, Power Management, Power Electronics, Electrical Machines and Drives
• Term: from 2019 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 410829522

The theory of frequency-adaptive simulation of transients（FAST）offers a methodological framework of multi-scale simulation of AC power systems. It relies on the addition of an orthogonal imaginary part to the real AC waveforms and so allowing the Fourier spectra of the resulting analytic signals to be shifted in the frequency domain. Without shifting, the real part of the analytic signal represents the original waveform. By shifting the spectrum of the analytic signal by the carrier of 50 Hertz towards lower frequencies, the carrier is effectively eliminated, and the envelope can be efficiently tracked at a large time step size. However, future power systems do not only rely on AC, but increasingly also on DC signals. AC/DC power systems with integrated AC and HVDC technologies including power electronic converters are of increasing interest, in particular also in China and Europe. The operation, control, and protection of AC/DC power systems are significantly more complex compared with the AC-only system.This project aims at pushing forward the state of art in multi-scale transient modeling and simulation of AC/DC power systems. The accurate and efficient simulation of diverse AC/DC transients across large time scales will support the in-depth analysis and opens the opportunity of real-time applications to ensure operational security and stability of AC/DC power systems. By developing multi-scale models of components with strong nonlinearities, such as power electronic converters or transformers in saturation, the modeling method based on the FAST frequency-shifting theory becomes fully capable of emulating large-scale AC/DC power grids.Taking full advantage of fine-grained parallel computing and the FAST method, a high-performance simulation technique and platform is researched and developed for speeding up multi-scale simulation to enable very fast and accurate AC/DC power system analysis. The platform is further enriched through cloud computing capabilities. The resulting functionality offers a novel paradigm of cooperative work on simulation. The concept will first be put into evidence by international collaboration between the project partners in Europe and China. It is then extended to contribute to broader collaboration of power-area academia and industry in both countries by offering highly scalable and efficient analytic capabilities.

• DFG Programme: Research Grants
• International Connection: China
• Partner Organisation: National Natural Science Foundation of China
• Cooperation Partners: Professor Dr. Ying Chen, Ph.D.; Professor Liangzhong Yao, Ph.D.