通过模仿皮肤效应缓解基于虚拟电导的电网形成逆变器结构谐振不稳定性
Mitigation of Structural Harmonic Instability in Virtual Admittance-Based Grid-Forming Inverters via Mimicking Skin Effect
AI总结：
本文提出通过模仿皮肤效应改进虚拟电导-电流控制器，以缓解电网形成逆变器的结构谐振不稳定性问题。
摘要：
虚拟电导-电流控制器（VA-CC）方案被广泛用于模拟电网形成逆变器内部电压源前的等效电感。然而，最近的研究报告了与VA-CC相关的谐振不稳定性，促使需要对它们的起源进行更物理上可解释的理解。本文字母识别了VA-CC方案中一种与延迟无关的结构谐振不稳定性机制，其中滤波器与虚拟电感之间的相互作用引入了一个非被动的二阶传递函数项，表现出负电阻。为了解决这个问题，提出了一种简单而有效的修改方法，通过将并联虚拟电阻集成到VA结构中。这种重新配置通过模仿皮肤效应增强了VA-CC方案在谐振范围内的被动性，从而在高频范围内增加阻尼，而无需改变已建立的电流控制器或电压前馈控制。实验结果验证了所提出方法在相同电网条件下实现了鲁棒的谐振稳定性，而传统方法在此条件下失效。
英文摘要：
The virtual admittance-current controller (VA-CC) scheme is widely employed to emulate an equivalent inductance in front of the internal voltage source of grid-forming inverters. However, recent studies have reported harmonic instabilities associated with VA-CC, motivating the need for a more physically interpretable understanding of their origin. This letter identifies a delay-independent structural mechanism of harmonic instability in the VA-CC scheme, wherein the interaction between the filter and virtual inductances introduces a non-passive second-order transfer-function term exhibiting negative resistance. To address this issue, a simple yet effective modification is proposed by integrating a parallel virtual resistor into the VA structure. This reconfiguration enhances the passivity of VA-CC scheme across the harmonic range by mimicking the skin effect which augments damping in high-frequency range, without altering the wellestablished current controller or voltage feedforward control. Experimental results validate that the proposed method achieves robust harmonic stability, whereas the conventional approach fails under identical grid conditions.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
