基于在线辨识的可控串补自适应控制

以三峡-万县500kV线路可控串补(TCSC)工程为背景，以抑制互联系统低频振荡为目的，提出了基于在线辨识的自适应移相式控制器。该控制器采用Prony方法在线辨识主振荡频率，并据此修改相位补偿环节参数，以消除频率变化对控制策略的不利影响，保证输出有适当的相位；在控制器中采用自动增益调节器，可在电力系统大振荡时用大增益控制，以充分发挥TCSC抑制振荡的能力，在振荡减小后则根据在线信息自动降低增益系数。文中对该控制器与固定串补(FSC)进行了比较，比较结果证明其性能优于后者。这表明该控制器对大电网互联系统低频振荡有良好的抑制作用，对运行条件和故障形式有很好的适应性及鲁棒性。控制器达到了系统对稳定性的要求，三一万线系统的仿真研究也验证了这一点。

SELF-TUNING PHASE-COMPENSATION CONTROL BASED ON ONLINE IDENTIFICATION OF TCSC

On the basis of the Thyristor controlled series compensation (TCSC) for the 500kV transmission line from Three Gorges Hydropower Station to Wanxian, an adaptive phase-shifting controller based on the online identification is presented. The frequency of inter-area oscillation is identified by prony algorithm and according to which the parameters of phase-shifting controller are meliorated to avoid the disadvantage impact engendered by deviation of frequency. A gain regulator which can choose large gain is applied in the controller to bring the TCSC into full play of damping the oscillation when intensive oscillation occurs in power system, after the oscillation is abated the gain coefficient can be automatically decreased according to the online information. The performance of the presented controller is compared with that of the fixed series compensation (FSC) and the comparison results show that the performance of the former is better than that of the latter, at the same time, it is shown also that the presented controller can effectively suppress the low frequency oscillation which occurs in the interconnected power grids. The simulation results of the 500kV transmission line from Three Gorges Hydropower Station to Wanxian show that the presented controller possesses good adaptiveness and high robustness.