电力系统暂态稳定性闭环控制(五)——控制量的实时计算

Closed-loop control of power system transient stability(5):calculation of control quantity

基于轨迹的凹凸性几何特征分析可知,不稳定的相轨迹斜率随角度逐步变大,欲使不稳定的轨迹向稳定的轨迹变化,施加的控制需要满足轨迹的斜率在功率平衡点前持续变小。据此提出了一种基于切机时刻相轨迹斜率和功率平衡点角度的最小切机量近似计算方法,并且给出了根据实测信息计算等值功率平衡点的近似计算方法。以单机无穷大系统和某联网电网系统为例,验证了理论的有效性。

The geometric analysis of trajectory convexity shows the slope of unstable phase trajectory increases gradually along with the angle. In order to stabilize the unstable trajectory,its slope should be controlled to become continuously smaller before the power balance point. A method is proposed to approximately calculate the minimum control quantity based on the phase trajectory slope of control point and the angle of power balance point. The equivalent power balance point is calculated approximately based on the measurements. A single machine infinite bus system and an interconnected system are taken as the examples to verify the validity of the introduced theory.