Towards Real Time Control of Oscillations in Electric Power Systems

这一建议解决了大范围、重载电力系统的有效安全控制问题，重点研究了大范围振荡的机制和前兆，以及在数据有限的情况下选择有效控制的问题。它的最终目标是使系统操作员能够检测潜在危险振荡的迫在眉睫，并采取预防措施，以避免对设备或系统造成危险。它仅限于考虑由系统条件的逐渐变化引起的自发振荡，以及由扰动引起的振荡。不考虑由不完全孤岛或脉动载荷引起的“强迫”振动。该提案在很大程度上借鉴了最近定义的“强烈共鸣”概念。提出了两个轻微衰减的振动模在共振附近相互作用的结论。如果线性化不可对角化，则称为强共振；如果可对角化，则称为弱共振。共振前频率发生变化的本征值在共振后会引起阻尼的变化，并随着阻尼经过零点而变得振荡不稳定。因此，模式共振被认为是电力系统振荡的可能前兆。

This proposal addresses the problem of effective security control of extensive, heavily loaded power systems, focusing on the study of mechanisms and precursors of widespread oscillations, and on the problems of selecting effective controls in the face of limited data. Its ultimate objective is to provide system operators with abilities to detect the imminence of potentially dangerous oscillations and to take preventive measures to avoid danger to equipment or the system. It is confined to consideration of spontaneous oscillations caused by gradual changes in system conditions, and to oscillations due to disturbances. "Forced" oscillations resulting from incomplete islanding or pulsating loads are not considered. The proposal draws heavily on the recently defined concept of "strong resonance." It is proposed that two lightly damped oscillatory modes interact near a resonance. "If linearization is not diagonizable, the resonance is called "strong;" if it is diagonizable, it is called "weak." An eigenvalue that changes in frequency before the resonance can change in damping after the resonance and become oscillatory unstable as the damping changes through zero." Thus, modal resonance is considered as a possible precursor of power system oscillations.