考虑时滞影响的电力系统广域集中励磁控制

Wide-Area Centralized Excitation Control in Power System Considering Influence of Time-Delay

针对电力系统区间低频振荡问题,构建了广域集中励磁控制(wide-area centralize dexcitation control,WCEC)框架。在充分考虑时滞影响的前提下,根据时滞输出反馈鲁棒控制理论设计了WCEC。广域测量系统实时测量反映区间低频振荡的状态变量,并将其传送至WCEC进行计算分析,WCEC把全局控制信号传送给相关机组的励磁系统,以此阻尼电力系统区间低频振荡。4机2区域电力系统的频域分析和时域仿真表明,WCEC在较宽的时滞区间内提高了系统的阻尼值,能够快速有效地抑制区间低频振荡,并且具有对运行状况的鲁棒性和对时滞类型的不敏感性。

For inter-area low-frequency oscillation in power systems, a framework for wide-area centralized excitation control （WCEC） is built. Fully considering the influence of time delay, a WCEC system is designed according to the theory of time-delay output-feedback robust control. Wide-area measurement system （WAMS） measures state variables reflecting inter-area low-frequency oscillation in real-time way and transmits the measured results to WCEC for calculation and analysis; WCEC transmits global control signals to excitation system of relevant generation units to dampen down inter-area low frequency oscillation in power systems. Results of frequency domain and time domain simulation of a 4-machine 2-area power system show that WCEC can increase the damping ratio of power system in a wider time delay range and can inhibit inter-area low frequency oscillation, meanwhile, WCEC possesses robustness to operation condition and insensitivity to the types of time delay.