基于小干扰稳定约束可用传输容量的计算

Available Transfer Capability Calculation With Small Signal Stability Constraints

小的干扰能够引发电力系统发生低频机电振荡,因此小干扰稳定是限制电力传输容量的主要因素之一。文中提出了一种基于小干扰稳定约束改进二阶连续潮流可用传输容量的计算方法,通过特征值的灵敏度指标重新调度发电出力,以改善电力系统的小干扰稳定性;针对发电机或传输线达到极限是一个非线性的现象,提出改进的二阶连续潮流可传输容量的算法,利用一阶指标中的附加信息来克服其线性不好的弱点,并通过控制变量的灵敏度计算减少了二阶连续潮流的搜索范围。新英格兰10机39节点系统的计算结果表明了用该方法计算ATC的有效性和可行性。

Small signal stability becomes one of the important factors influencing transmission capacity because low frequency oscillation in power systems is always caused by small interference. This article proposes a method for calculating available transfer capability （ATC） based on improved second order continuation taking small signal stability constraints into consideration. In this proposed method, the electric power output of the generators of the power systems are re-dispatched in order to improve small signal stability of the power system according to eigenvalue sensitivity index. An improved method of second order continuation power flow is proposed, in which the additional information of the first order index is made to overcome its linear weakness, and the searching range of second order continuation power flow is reduced by the variable sensitivity computation of the control variables. A simulation example is given to illustrate the proposed method in New England power systems with 10 units and 39 buses. The simulation results show that ATC calculation is effective and feasible using the proposed method.