Wave Function and Multiscale Modeling of MMC-HVdc System for Wide-Frequency Transient Simulation

The detailed modeling of power electronic (PE) devices poses challenging problems to an efficient transient simulation large-scale PE-dominated systems. As PE paradigm, a multiscale methodology the modular multilevel converter (MMC) for simulating diverse transients from low-frequency oscillations up high-frequency switching events in MMC high-voltage direct current (HVdc) system is developed, implemented, and validated. novelty lies creation wave propagation function (WPF) that describes submodule (SM) behavior, then, SM Fourier series-based shifted-frequency phasor (SFP) developed accelerate computation speed system-level dynamics. These efforts serve as basis where multiple-frequency shifting achieved. By implementing seamless model interface with control systems, applicable MMC-HVdc transmission system. validated through case studies cover dc fault, internal oscillations, wind fluctuations. computational accuracy efficiency are verified comparison results those full electromagnetic (EMT) model.