This letter proposes an efficient method for com-puting the delay-margins of large-scale power systems with single constant delay. The method computes the margin by identifying the minimal delay under which some eigenvalues are about to cross the imaginary axis from the left to the right half complex plane. Based on the Rekasius substitution, a new characterization for the crossing points is developed, followed by a method for determining the delay margins. The method only involves eigen-value decomposition on a low-order matrix whose dimension is independent of the system scale. Further leveraging the sparsity of power systems makes it computationally very attractive for practical large-scale system applications.

中文翻译：

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一种计算大型电力系统精确延迟裕度的有效方法

这封信提出了一种计算具有单个恒定延迟的大型电力系统的延迟裕度的有效方法。该方法通过识别最小延迟来计算余量，在该最小延迟下，一些特征值即将从左半复平面穿过虚轴。基于 Rekasius 替代，开发了交叉点的新特征，然后是确定延迟裕度的方法。该方法只涉及对维数与系统尺度无关的低阶矩阵进行特征值分解。进一步利用电力系统的稀疏性使其在计算上对实际的大规模系统应用非常有吸引力。