TCSC阻抗特性及其导通角对次同步谐振的抑制分析

摘要

为了解决目前普遍应用的TCSC基波阻抗公式无法解释次频正电阻的问题，推导了TCSC基波阻抗的复数表达式，提出了TCSC导通角的选择依据。利用基波阻抗的复数形式，分析得到TCSC受导通角影响，基波电抗呈现出感性或容性特征，基波电阻会表现出负电阻和正电阻特性；次频电抗也会表现出感性或容性特征，次频电阻始终呈现正值。通过改变导通角使次频电抗呈感性能有效抑制SSR，使工频电阻为负值能够给次频正电阻提供能量；导通角的选择应同时满足工频下电抗呈容性、次频下呈感性以及工频下电阻为负值。算例分析表明, TCSC基于上述依据选择导通角能有效抑制系统的SSR，证明了导通角选择的合理性和基波阻抗表达式的正确性。%In-order-to-explain-the-positive-resistance-phenomenon-of-sub-synchronous-frequency-based-on-the-commonly-used-fundamental-frequency-impedance-of-TCSC,-the-complex-expression-of-fundamental-frequency-impedance-is-derived-and-selection-principle-of-TCSC-conduction-angle-is-proposed.-The-fundamental-frequency-reactance-of-TCSC-is-capacitive-or-inductive-and-its-resistance-will-be-negative-or-positive.-The-sub-synchronous-reactance-of-TCSC-will-also-be-capacitive-or-inductive-and-the-sub-synchronous-resistance-is-always-positive-with-conduction-angle’s-influence.-Inductive-reactance-plays-a-major-role-for-SSR-mitigation-and-power-frequency-negative-resistance-provides-energy-to-the-positive-resistance-under-sub-synchronous-frequency.-TCSC-conduction-angle’s-selection-should-make-sure-that-the-reactance-should-be-capacitive-under-power-frequency,-and-inductive-under-sub-synchronous-frequency,-meanwhile-the-power-frequency-resistance-should-be-negative.-Simulation-results-show-that-TCSC-can-mitigate-SSR-effectively-based-on-the-above-basis.-It-proves-rationality-of-selecting-the-conduction-angle-and-correctness-of-the-fundamental-frequency-impedance-expression.