The interaction between the three-phase voltage source converters (VSCs) and the power grid may cause high-frequency resonant instable problems. Studies have indicated that the non-passivity of VSCs is the main reason that leads to the resonances. The above-mentioned passive means that the equivalent output admittance of the VSC has a positive real part. In this paper, a novel damped Smith predictor is proposed to suppress the resonant instability problem that caused by time delay. The research proved that the proposed Smith predictor can significantly improve the passivity of the VSC by reducing the width of the negative real part at the high-frequencies. Simulation and experimental results demonstrate that the proposed Smith predictor can distinctly improve the robustness of the VSC.

中文翻译：

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一种新的基于无源性的并网 VSC 谐振不稳定性抑制方法

三相电压源换流器 (VSC) 与电网之间的相互作用可能会导致高频谐振不稳定问题。研究表明，VSC 的非被动性是导致共振的主要原因。上述无源意味着VSC的等效输出导纳具有正实部。在本文中，提出了一种新颖的阻尼史密斯预测器来抑制由时间延迟引起的谐振不稳定问题。研究证明，所提出的史密斯预测器可以通过减少高频负实部的宽度来显着提高 VSC 的无源性。仿真和实验结果表明，所提出的史密斯预测器可以明显提高 VSC 的鲁棒性。