集群风场系统链式SVG高频谐振分析与抑制

针对含链式静止无功发生器(static var generator, SVG)的风场区域系统高频谐振问题，首先采用谐波线性化的方法建立包含锁相环、功率外环以及电流内环在内的SVG谐波阻抗模型。利用阻抗分析法对风场区域空载线路投入对SVG稳定性的影响进行分析，揭示风场区域系统高频谐振的发生机理。然后，为抑制系统高频谐振，提出一种基于电压前馈附加带阻滤波器的SVG高频谐振抑制策略。对SVG侧中高频段等效阻抗进行重塑，以保证在该频段系统呈正阻尼状态。并讨论带阻滤波器中心频率和阻尼系数对系统相位裕度的影响。最后利用搭建的含链式SVG风场区域系统仿真模型，验证了理论分析的正确性和所提抑制策略的有效性。

Analysis and suppression of chained SVG high-frequency resonance in a cluster wind farm system

To solve the high frequency resonance problem of a wind field regional system with a chained static var generator (SVG), an SVG harmonic impedance model including phase-locked, power outer and current inner loops is first established by the harmonic linearization method. An impedance analysis method is applied to the unloaded line in the wind field area to analyze the effect on the stability of the SVG. This reveals a high frequency resonance mechanism of the wind field regional system. Then, to suppress the high frequency resonance of the system, an SVG-BASED high frequency resonance suppression strategy based on additional band stop filter is proposed in the voltage feedforward compensator. The equivalent impedance of the SVG side in the middle and high frequency band is reconstructed to ensure that the positive damping state of the system is in the band. The influence of the center frequency and damping coefficient of the band stop filter on the phase margin of the system is discussed. Finally, a simulation model of the wind field area system containing chained SVG is used to verify the correctness of the theoretical analysis and the effectiveness of the proposed suppression strategy.This work is supported by the National Natural Science Foundation of China (No. 52077030).