【摘要】 基于复转矩系数法与特征根法,对交直流(AC/DC)并联系统的次同步振荡(SSO)阻尼特性进行了分析.结果表明,逆变侧交流系统的强度以及逆变站控制方式对SSO阻尼有显著的影响.运用H∞鲁棒控制理论设计了直流附加次同步阻尼控制器(SSDC),把逆变侧交流短路阻抗变化、逆变站控制方式的改变以及系统运行条件变化所引起的系统模型幅频特性的差异,看作系统模型的不确定性,把控制器的设计归结为H∞鲁棒控制理论中混合灵敏度问题的求解.特征根分析与仿真表明,SSDC具有良好的鲁棒性.更多还原

【Abstract】 Based on complex torque coefficient method and eigenvalue analysis, the subsynchronous oscillation(SSO) damping characteristics of an AC/DC parallel system were studied.The result shows that both AC bus strength and the control mode of inverter side have a remarkable effect on SSO damping. H_∞ robust control theory was used to design a supplementary subsynchronous damping controller (SSDC), the variation of system magnitude-frequency characteristics caused by the variation of inverter AC short-circuit impedance and the change of inverter control modes are considered as the uncertainty of system model, and the design of SSDC can be converted to a problem of mixed sensitivity in H_∞ robust control theory. The eigenvalue analysis and time-domain simulation show that the proposed SSDC has good robust performance.更多还原