Frequency-Domain Stability Criteria for Converter-Based Power Systems
Frequency-Domain Stability Criteria for Converter-Based Power Systems
复制标题
基于转换器的电力系统的频域稳定性标准
DOI：
--
复制
发表时间：
2022
影响因子：
5.8
通讯作者：
Jian Sun
中科院分区：
文献类型：
--
作者：
Jian Sun
针对具有任意数量变流器的基于变流器的电力系统，开发了频域稳定性准则。变流器可以是网格跟随或网格形成，网格可以是交流或混合交直流网络。转换器和网络都在基于小信号序列阻抗的通用（平稳）参考系中建模。频率耦合和交直流耦合是最一般的形式。对于每种类型的系统，首先通过节点分析建立频域模型，然后重新制定以适应实际条件下保证开环稳定性的反馈回路形式。系统稳定性由奈奎斯特判据确定，无需检查开环右半平面极点。进一步简化系统模型是可能的：a)广义的$n$端口等效电路，包括两种类型的耦合，b)内部和外部节点的稳定性等效，以及c)扰动时的动力学与耦合频率之间的关系。针对几种特殊系统，提出了将系统模型简化为单独的单输入-单输出模型的方法及其实际应用。给出了定量和实验结果来验证所建立的理论。
Frequency-domain stability criteria are developed for converter-based power systems with any number of converters. The converters may be grid following or grid forming, and the grid can be an ac or hybrid ac-dc network. The converters and the network are all modeled in a common (stationary) reference frame based on small-signal sequence immittances. Coupling over frequency and ac-dc coupling are considered in the most general form. For each type of systems, a frequency-domain model is developed first by nodal analysis and then reformulated to fit the form of a feedback loop with open-loop stability guaranteed by practical conditions. System stability is then determined by a Nyquist-like criterion without the need to check open-loop right-half-plane poles. Further simplification of the system models is made possible by a) generalized $n$-port equivalent circuits that include both types of coupling, b) equivalence of stability at internal and external nodes, and c) relationship between dynamics at the perturbation and the coupling frequency. Reduction of a system model into separate single-input-single-output models is presented for several special systems along with their practical applications. Quantitative and experimental results are presented to verify the developed theories.