This article presents a systematic evaluation on the impedance passivity of voltage-controlled voltage-source converters. The commonly used single- and dual-loop control structures with different linear controllers are compared extensively, considering the effect of the time delay involved in the control loop. A virtual impedance control, co-designed with different voltage control schemes, is then proposed to eliminate the negative output resistance till half of the sampling frequency, which improves the system stability for grid-forming converters in grid-connected applications. Both frequency-domain analysis and experimental results validate the theoretical findings.

中文翻译：

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基于无源性的电压源转换器线性电压控制器的分析和设计

本文对压控电压源转换器的阻抗无源性进行了系统评估。考虑到控制回路所涉及的时间延迟的影响，广泛比较了具有不同线性控制器的常用单回路和双回路控制结构。然后提出了与不同电压控制方案共同设计的虚拟阻抗控制，以消除负输出电阻直至采样频率的一半，从而提高了并网应用中的网格形成转换器的系统稳定性。频域分析和实验结果均验证了理论发现。