交流互联电网中大扰动对联络线的冲击特性分析方法

A Method for Analyzing Large Disturbance Impact Characteristics on Tie-line in AC Interconnected Power Grid

针对在规模庞大的同步交流电网中,区域内大扰动不仅会对本区域电网稳定性造成冲击,而且将通过区域间联络线对其他区域电网的稳定性产生冲击,甚至会导致区域联络线功率振荡解列的现象,研究了故障后大扰动冲击各个区域电网的特性。基于联络线暂态势能变化,定义了扰动起始冲击时间和扰动冲击时间,可以定量描述大扰动冲击区域交流联络线的过程,并根据首次扰动冲击时间联络线功率偏差与暂态势能间的关系,提出了联络线脆弱性指标作为系统是否在联络线处发生解列的判据,从而建立了基于能量函数的大扰动冲击特性定量描述方法。最后,在华中—华北交流互联电网中验证了所述方法的有效性。

For the large-scale synchronous AC grid, the large disturbance within the region will impact not only the grid stability in the region, but also that in other regions through the interregional tie-line, even leading to interregional tie-line power oscillation split. Following a look into the large disturbance impact characteristics on the tie-line between regional power grids, the disturbance impact start time and impact time are defined based on the characteristic of tie-line transient potential energy to quantitatively describe the disturbance impact process of the large fault. According to the relationship between tie-line potential energy and the active power at disturbance impact time, a tie-line stability criterion is also proposed, thereby forming a quantitative description method of the large disturbance impact characteristics based on the energy function. The method proposed is verified in the Central-North China power grid.