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

频率自适应暂态仿真（FAST）理论为交流电力系统多尺度仿真提供了一个方法框架。它依赖于将正交虚部添加到真实的AC波形，并且因此允许所得到的分析信号的傅立叶频谱在频域中移位。在没有移位的情况下，分析信号的真实的部分表示原始波形。通过将分析信号的频谱向较低频率移动50赫兹的载波，有效地消除了载波，并且可以以大的时间步长有效地跟踪包络。然而，未来的电力系统不仅依赖于AC，而且越来越依赖于DC信号。具有集成AC和HVDC技术的AC/DC电力系统（包括电力电子转换器）越来越受到关注，特别是在中国和欧洲。交直流电力系统的运行、控制和保护比纯交流系统复杂得多，本项目旨在推动交直流电力系统多尺度暂态建模与仿真的发展。跨大时间尺度的各种AC/DC瞬态的准确和高效的仿真将支持深入的分析，并打开实时应用的机会，以确保AC/DC电力系统的运行安全和稳定。基于FAST移频理论的建模方法通过建立电力电子变换器或饱和变压器等强非线性元件的多尺度模型，使其完全具备了对大规模交直流电网进行仿真的能力，充分利用了FAST方法的细粒度并行计算能力，研究和开发了一种高性能仿真技术和平台，用于加速多尺度仿真，以实现非常快速和准确的AC/DC电力系统分析。该平台通过云计算能力得到进一步丰富。由此产生的功能提供了一个新的模式，合作工作的模拟。这一概念将首先通过欧洲和中国的项目合作伙伴之间的国际合作来证明。然后，它通过提供高度可扩展和高效的分析能力，为两国电力领域学术界和工业界的更广泛合作做出贡献。

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.