论文标题
通过时间尺度分离的下垂控制的基于逆变器的电网的稳定性分析
Stability Analysis of Droop-Controlled Inverter-Based Power Grids via Timescale Separation
论文作者
论文摘要
我们考虑了具有下垂控制的逆变器和动态分配功率线的分配网格的稳定性分析问题。将逆变器建模为具有可控频率和振幅的电压源。对于大型网络而言，由于数值模拟和详细的特征值分析是有影响力的，因此这个问题非常具有挑战性。在上述局限性的推动下，我们在本文中提出了一个系统和计算有效的框架，用于基于逆变器的分布网格的稳定性分析。为了设计我们的框架，我们使用奇异扰动和Lyapunov理论的工具。有趣的是，我们表明，功率电网快速动力学的稳定性仅取决于逆变器的电压下垂增长，而缓慢动力学的稳定性取决于电压和频率下垂的增长。最后，通过利用这些时间尺度的分离属性，我们在逆变器的频率和电压下垂增长方面得出了充分的条件，这些逆变器需要保证完整系统的稳定性。我们通过在IEEE 13-BUS分布网格上的数值示例来说明我们的理论结果。
We consider the problem of stability analysis for distribution grids with droop-controlled inverters and dynamic distribution power lines. The inverters are modeled as voltage sources with controllable frequency and amplitude. This problem is very challenging for large networks as numerical simulations and detailed eigenvalue analysis are impactical. Motivated by the above limitations, we present in this paper a systematic and computationally efficient framework for stability analysis of inverter-based distribution grids. To design our framework, we use tools from singular perturbation and Lyapunov theories. Interestingly, we show that stability of the fast dynamics of the power grid depends only on the voltage droop gains of the inverters while, stability of the slow dynamics, depends on both voltage and frequency droop gains. Finally, by leveraging these timescale separation properties, we derive sufficient conditions on the frequency and voltage droop gains of the inverters that warrant stability of the full system. We illustrate our theoretical results through a numerical example on the IEEE 13-bus distribution grid.
