Nonlinear Modular State-Space Modeling of Power-Electronics-Based Power Systems

This dataset contains the Matlab code of the nonlinear state-space model of a power electronics-dominated grid. A power grid with 3 grid following converters is taken under consideration, following the publication:F. Cecati, R. Zhu, M. Liserre and X. Wang, "Nonlinear Modular State-Space Modeling of Power-Electronics-Based Power Systems," in IEEE Transactions on Power Electronics, vol. 37, no. 5, pp. 6102-6115, May 2022, doi: 10.1109/TPEL.2021.3127746.Abstract of the paper:Power system state-space models are often constructed by interconnection of their subsystems (converters, distribution lines, and grid). The interconnection between L-/LCL-filtered converters with the distribution lines subsystems is often realized through a virtual resistor, because they both have the voltage as input, introducing inaccuracy. Moreover, the parameters variations influence not only the eigenvalues, but also the equilibrium point. In this case, the small-signal model has to be reevaluated around the new equilibrium point. For the computation of the equilibrium point, an additional method, e.g., power flow, is conventionally used. However, the variables computed with power flow (e.g., P,Q,V, and θ) do not always coincide with the state-space model variables, required for the linearization. Furthermore, the traditional power flow does not consider the influence of the voltage-source-converter control system on the grid equilibrium point. This article proposes a nonlinear grid model that does not need the virtual resistor to be interconnected. The proposed model can be used both for equilibrium point computation through the Newton–Raphson method, and it can be linearized around the computed equilibrium point for small-signal analyses. Simulations and experiments are provided.

本数据集收录了基于电力电子主导电网的非线性状态空间模型的 Matlab 代码。本模型考虑了包含三个电网跟随转换器的电力网格，并遵循了以下出版物：F. Cecati, R. Zhu, M. Liserre 及 X. Wang，发表在《IEEE Transactions on Power Electronics》杂志第 37 卷第 5 期，页码 6102-6115，2022 年 5 月，DOI：10.1109/TPEL.2021.3127746 的论文：“基于电力电子的电力系统非线性模块化状态空间建模”。论文摘要如下：电力系统的状态空间模型通常通过子系统（转换器、配电线路和电网）的互联构建。L-/LCL 滤波器转换器与配电线路子系统之间的互联通常通过虚拟电阻实现，因为它们都以电压为输入，这引入了误差。此外，参数的变化不仅影响特征值，还会影响平衡点。在这种情况下，必须围绕新的平衡点重新评估小信号模型。为了计算平衡点，通常采用额外的计算方法，例如潮流计算。然而，潮流计算得到的变量（例如，P、Q、V 和 θ）并不总是与线性化所需的状态空间模型变量相一致。此外，传统的潮流计算未考虑电压源转换器控制系统对电网平衡点的影响。本文提出了一种无需虚拟电阻互联的非线性电网模型。所提出的模型可用于通过牛顿-拉夫森方法计算平衡点，并且可以在计算出的平衡点周围进行小信号分析。同时提供了仿真和实验结果。