系统惯性时间常数对互联电网暂态稳定水平的影响

由于区域电网的互联,整个系统的惯性时间常数将会发生明显变化,继而会影响整网的暂态稳定水平。基于暂态能量函数法,通过对等值2机系统进行数学推导并作暂态稳定分析,研究了系统在各种运行方式下,2端机组惯量变化对电力系统暂态稳定水平产生的影响,比较了两端机组惯量变化分别对系统暂态稳定性的影响,并发现了系统机组惯性时间常数对系统暂态稳定水平造成的影响与系统的负荷水平及初始工况有关。在理论分析的基础上,结合相关算例在各种运行方式下进行了仿真研究,仿真结果验证了分析结果的正确性。

Influence of System Inertia Time Constants on Transient Stability Level of Interconnected AC Power Grid

Due to the interconnection of regional power grids,the inertia time constant of the whole interconnected grid evidently changes,then transient stability level of the interconnected power grid will be influenced.Based on transient energy function,by means of mathematical deduce for equivalent two-machine system and analysis on its transient stability,the influences of unit inertial changes at both terminals on transient stability level of the whole system under various operation modes are researched,and respective influences of terminal unit inertial changes on transient stability of the whole grid are compared,besides,it is found that the influences of unit inertial time constants on system transient stability level are relevant to load level and initial operating condition of the power grid.Based on theoretical analysis,simulation of concerned examples under various operation modes is performed and the correctness of theoretical analysis results is verified by simulation results.