应用动态相量模型分析高压直流输电引起的次同步振荡现象

ANALYSIS AND SIMULATING THE SSO CAUSED BY HVDC USING THE TIME-VARYING DYNAMIC PHASOR

时变动态相量已被成功地引入电力系统以分析其动态行为。与传统的相量相比,时变动态相量具有显著的优点。该文应用动态相量模型分析由HVDC引起的次同步振荡现象,并以直流网络为例,采用特征值分析和复转矩频率扫描方法,获得了全系统的特征值与控制系统参数变化的关系,以及在特定的模式下电气阻尼与机械阻尼的情况。由此得出结论:利用时变动态相量模型可简单、方便地分析高压直流输电引起的次同步振荡现象。

The concept of Time-Varying Dynamic Phasor has already been successfully brought into electric power system to analyze dynamics. It offers many advantages over conventional 搎uasi-stationary?phasor. In this paper, we apply dynamic phasor to analyze the SSO phenomena caused by HVDC. The methods include eigen-analysis and complex torque scanning. As a sample network studied in this paper, we get how eigenvalues vary with parameters of control system by analyzing eigenvalues of whole system. While using complex torque scanning method, we analyze the interaction between electrical damping and mechanical damping. So, we draw a conclusion that dynamic phasors are more convenient and simpler compared with traditional methods used to analyze SSO or SSR.