A sub-/super-synchronous interaction (sub-/super-SCI) can occur between a voltage source converter-based high-voltage direct current (VSC-HVDC) and the permanent magnet synchronous generator (PMSG)-based wind farms with long AC transmission lines. However, the influencing factors have not been properly analyzed. In this paper, these are deconstructed and mathematically analyzed from detailed small-signal impedance equations in the dq-frame and the corresponding Bode stability criterion. Distinguishing conclusions from existing papers are obtained by studying the controllers’ bandwidths instead of their coefficients. The impacts of AC line impedance on system stability are also investigated. From the analysis of their compositions in impedance structure, the VSC-HVDC bandwidths and the wind farm phase-locked loop (PLL) bandwidth and power ratio, and the AC line impedance have various influences on the system stability. Meanwhile, the wind farm outer DC voltage and inner current control bandwidths have little impact on system stability. The results of these studies show that the magnitude in the axes q-axes impedance interaction is the essential factor for system instability. Our studies also show system stability is more sensitive to the HVDC bandwidths than the wind converter PLL bandwidth. The simulation results verify our theory conclusions.

中文翻译：

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基于阻抗波特准则的 VSC-HVDC 和 PMSG-风电场系统的 Sub-/Super-SCI 影响因素分析

基于电压源换流器的高压直流 (VSC-HVDC) 和基于永磁同步发电机 (PMSG) 的风电场之间可能发生亚/超同步相互作用 (sub-/super-SCI)。交流传输线。然而，影响因素还没有得到适当的分析。在本文中，这些是从dq 中详细的小信号阻抗方程解构和数学分析的-frame 和相应的 Bode 稳定性准则。通过研究控制器的带宽而不是它们的系数，可以获得与现有论文的区别结论。还研究了交流线路阻抗对系统稳定性的影响。从它们的阻抗结构组成分析，VSC-HVDC带宽和风电场锁相环（PLL）带宽和功率比，以及交流线路阻抗对系统稳定性有不同的影响。同时，风电场外部直流电压和内部电流控制带宽对系统稳定性影响不大。这些研究的结果表明，在幅度轴q -轴阻抗相互作用是系统不稳定的重要因素。我们的研究还表明，系统稳定性对 HVDC 带宽比对风能转换器 PLL 带宽更敏感。仿真结果验证了我们的理论结论。