Abstract In this article, the interactions between AC grid and existing VSC control modes are analyzed. First, three VSC control modes, namely grid-feeding, grid-supporting and grid-forming, are compared with each other in order to assess VSC/grid coupling level. Then, in order to underscore the growing role of VSCs in transmission systems, an elementary benchmark network is considered. It includes an equivalent SM (Synchronous Machine), a VSC, a load and a transmission line with a varying electrical distance. Thereafter, a modal analysis is conducted on this model to study the interactions between the different VSC controls and the SM dynamics using a Matlab/Simulink environment. The converter penetration rate is represented by a variable power ratio between the converter and the machine, while the electrical distance by an RL dynamic impedance. This approach makes it possible to assess the stability limits on the VSC share imposed by the system strength. Negative interactions are identified and recommendations for novel converter control strategies proposed. Besides, the influence of the AVR with the VSC in grid-forming as well as PLL-related stability issues with the VSC in grid-feeding or grid-supporting are shown to be the key limiting factors for increasing the penetration of PE-based sources.

中文翻译：

---

使用模态分析了解 VSC 控制策略在交流电网中电力电子集成限制中的作用

摘要 本文分析了交流电网与现有VSC 控制模式之间的相互作用。首先，将并网、并网和并网三种VSC控制模式相互比较，以评估VSC/电网耦合水平。然后，为了强调 VSC 在传输系统中日益增长的作用，我们考虑了一个基本的基准网络。它包括等效的 SM（同步电机）、VSC、负载和具有不同电气距离的传输线。此后，对该模型进行模态分析，以使用 Matlab/Simulink 环境研究不同 VSC 控制与 SM 动力学之间的相互作用。转换器渗透率由转换器和机器之间的可变功率比表示，而电气距离由 RL 动态阻抗表示。这种方法可以评估系统强度对 VSC 份额的稳定性限制。确定了负面相互作用，并提出了对新型转换器控制策略的建议。此外，AVR 与 VSC 在电网形成中的影响以及 VSC 在电网馈电或电网支持中的 PLL 相关稳定性问题被证明是增加基于 PE 的源渗透的关键限制因素.