论文标题
几乎全球稳定的自适应相锁环，用于同步网格连接的电压源转换器
An Almost Globally Stable Adaptive Phase-Locked Loop for Synchronization of a Grid-Connected Voltage Source Converter
论文作者
论文摘要
在本文中，我们对电压源转换器的自适应同步的问题感兴趣，该电压源转换器的网格可能较弱，角度和频率未知，但了解其参数。为了确保与三相网格电压的角度进行合适的同步，我们为仅在共同耦合点上进行测量的信号设计了一个自适应观察者。然后，我们提出了两个替代性确定性等值的，自适应的相锁环，以确保在几乎所有初始条件下的角度估计误差为零。尽管众所周知，但为了完整性，我们还提出了一个具有前馈作用的PI控制器，以确保转换器电流收敛到任意所需的值。理论结果的相关性及其与网格参数变化的鲁棒性的相关性在与短相位低相关的网格的挑战性情况下进行了详尽的讨论和验证。
In this paper we are interested in the problem of adaptive synchronization of a voltage source converter with a possibly weak grid with unknown angle and frequency, but knowledge of its parameters. To guarantee a suitable synchronization with the angle of the three-phase grid voltage we design an adaptive observer for such a signal requiring measurements only at the point of common coupling. Then we propose two alternative certainty-equivalent, adaptive phase-locked loops that ensure the angle estimation error goes to zero for almost all initial conditions. Although well-known, for the sake of completeness, we also present a PI controller with feedforward action that ensures the converter currents converge to an arbitrary desired value. Relevance of the theoretical results and their robustness to variation of the grid parameters are thoroughly discussed and validated in the challenging scenario of a converter connected to a grid with low short-circuit-ratio.
