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arXiv 2108.04667eess.SYcs.SY
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随机扰动下电力系统的同步

Synchronization of Power Systems under Stochastic Disturbances

Zhen Wang, Kaihua Xi, Aijie Cheng, Hai Xiang Lin, André C. M. Ran, Jan H. van Schuppen, Chenghui Zhang

AI总结:

本文研究随机扰动下电力系统同步问题,用布朗运动建模扰动并提出频率与相角差方差计算方法,给出均匀情形显式公式、非均匀情形界及网络结构影响。

摘要:

发电机同步是电力系统正常运行的重要条件,即在受到随机扰动时,发电机之间的频率波动和相角差足够小。严重波动会引发失步,并可能导致大面积停电。本文在非线性电力系统的线性化系统中,用 Brownian motion(布朗运动)过程对随机扰动建模,并通过不变概率分布中频率与相角差的方差来刻画波动。我们提出一种计算频率和相角差方差的方法。对于具有均匀扰动-阻尼比的系统,推导了频率和相角差方差矩阵的显式公式。结果表明,节点处的频率波动仅取决于该节点的扰动-阻尼比和惯量,而线路上的相角差波动与惯量无关。特别地,同步稳定性与网络的环空间有关。我们揭示了建设新线路和提高线路容量对现有线路相角差波动的影响。相关结果以中国山东省输电系统为例进行了说明。对于具有非均匀扰动-阻尼比的系统,我们进一步得到了方差矩阵的界。

英文摘要:

The synchronization of power generators is an important condition for the proper functioning of a power system, in which the fluctuations in frequency and the phase angle differences between the generators are sufficiently small when subjected to stochastic disturbances. Serious fluctuations can prompt desynchronization, which may lead to widespread power outages. Here, we model the stochastic disturbance by a Brownian motion process in the linearized system of the non-linear power systems and characterize the fluctuations by the variances of the frequency and the phase angle differences in the invariant probability distribution. We propose a method to calculate the variances of the frequency and the phase angle differences. For the system with uniform disturbance-damping ratio, we derive explicit formulas for the variance matrices of the frequency and the phase angle differences. It is shown that the fluctuation of the frequency at a node depends on the disturbance-damping ratio and the inertia at this node only, and the fluctuations of the phase angle differences in the lines are independent of the inertia. In particular, the synchronization stability is related to the cycle space of the network. We reveal the influences of constructing new lines and increasing capacities of lines on the fluctuations in the phase angle differences in the existing lines. The results are illustrated for the transmission system of Shandong Province of China. For the system with non-uniform disturbance-damping ratio, we further obtain bounds of the variance matrices.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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