基于能量函数的TCSC阻尼控制器仿真研究

Simulation Research on TCSC Damping Control Based on Energy Function

基于可控串补(TCSC)在系统故障情况下,会由于积聚多余能量而产生误动作,影响其阻尼效果的考虑,设计了在PID控制上附加基于联络线修正能量控制策略的新型分段控制TCSC阻尼控制器。通过设计联络线修正能量函数,推导出了联络线上TCSC输出阻抗的最佳控制时间,与联络线修正能量取特殊值时刻的重合关系。即在联络线修正动能最大时刻,控制TCSC输出最大容性电抗,增加系统阻尼。在修正势能最大时刻,且系统运行在稳定域边界或稳定域内时,控制TCSC适当工作于小电感的旁路模式,能消除TCSC积聚的多余能量。对比常规PID阻尼控制器,时域仿真结果和频域仿真结果都表明,所设计的阻尼控制器对系统低频振荡的抑制效果更明显。

Excess energy of controlled series compensation （TCSC） accumulated in failure conditions causes its malfunction affects its damping effect. Therefore, a new TCSC segment damping controller installed in tie-line was designed based on the tie-line correction energy function. The coincidence relation was built between the moment of optimal control of TCSC output impedance and the moment of the special value of tie-line correction energy. That is, TCSC is controlled for maximum output capacitive reactance at the moment of maximum of tie-line correction kinetic energy to increase the system damping, and for small inductive reactance at the moment of maximum potential energy and the system operating point being on the stability boundaries or in the stability region to eliminate excess energy. Comparing conventional PID damping controller, the simulation results of both time-domain and frequency-domain show that the proposed damping controller is more effective to inhibit system low frequency oscillation.