面向逆变器型分布式电源的快速建模与仿真方法

在利用数值仿真方法研究逆变器型分布式电源大规模接入配电网的特性和影响时,采用详细模型因涉及非线性的电力电子器件,仿真步长需选取很小,致使仿真速度缓慢,而采用过于简化的模型又不能完整反映系统的动态特性,因此有必要研究准确、高效的分布式电源建模方法。在正负序分离控制的基础上,详细分析了逆变器型分布式电源的动态相量建模方法,并且在PSCAD/EMTDC中建立了分布式电源的电磁暂态模型,同时在MATLAB/Simulink中建立了等效动态相量模型。通过仿真比较,结果表明采用的动态相量模型在配电网电压对称、不对称工况及故障情况下均能准确地反映系统运行的动态过程,并显著加快仿真速度,适合应用于逆变器型分布式电源高渗透率下配电网运行特性的快速仿真。

Rapid Modeling and Simulation Method for Inverter-interfaced Distributed Generators

When studying the characteristics and influences of distribution network with high penetration of inverter-interfaced distributed generators(DGs)using numerical simulation methods, the emulating step size is chosen very small as the adoption of detailed models involves nonlinear power electronic devices. As oversimplified models cannot fully reflect system dynamic properties, accurate and efficient modeling methods are badly needed. The modeling approach is analyzed using a detailed dynamic phasor model based on positive and negative sequence separation control strategy. PSCAD/EMTDC is used in developing a DGs'' electromagnetic transient model while the corresponding dynamic phasor model is simulated using MATLAB/Simulink simultaneously. Comparisons of simulation results indicate the dynamic phasor model adopted can imitate the dynamic process of power system accurately under symmetrical, asymmetrical voltage conditions and fault conditions, and accelerate simulation remarkably, which is suitable for rapid simulation of distribution network with high penetration of inverter-interfaced DGs.