用于电力电子变换器集成电力系统的电磁暂态仿真分裂状态空间方法

As the utilization of power electronic-based components in power systems continues to grow, a comprehensive understanding of their dynamics becomes increasingly important for system design, control and protection analysis. To meet practical needs, the high-fidelity but time-consuming electromagnetic transient (EMT) simulations are often required. To improve the performance of these simulations, a highly efficient splitting state-space method with numerical error control is proposed that reduces the computation workload. The method employs a generic decoupling principle to split the state-space equations of the converter-integrated power system and introduces the exponential splitting formulas of multiple orders accuracy to solve and then compose the splitting state-space equations. The decoupling principle is designed based on separation of time-varying portions of the state matrix, which is realized by locating the smallest subcircuit topology that is switch state-dependent, through automatic switch grouping and switch adjacent state variables (SASV) identification. A family of exponential splitting schemes is employed to accelerate the demanding matrix exponential calculation. The splitting state-space method undergoes comprehensive testing across various cases, including a distribution network with DC load, an LLC resonant converter, a large-scale wind farm, and an MMC circuit. The accuracy of the proposed method is thoroughly evaluated, and its efficiency is validated.