基于Prony分析的多机系统电磁转矩系数计算

Computation of Electric Torque Coefficients in Multi-Machine Power Systems Based on Prony Analysis

同步转矩及阻尼转矩是两个在动态稳定研究中广泛应用的概念,它们对于电力系统低频振荡分析尤为重要。文章首先分析了现有的发电机电磁转矩系数算法,指出该算法在多种低阻尼的低频振荡模式并存的系统中会失效。然后提出了新的基于Prony分析的多机系统电磁转矩系数算法,新算法不仅继承了原有算法不依赖于具体模型和参数的优点,而且克服了原有算法的缺点。最后,借助新算法揭示了电磁转矩分析与分岔分析之间的联系,给出了对于阻尼转矩更深刻的认识。

Synchronizing torque and damping torque are two concepts widely used in dynamic stability studies and especially important to low-frequency oscillation analysis. Firstly, the authors analyze existing algorithm for electric torque coefficient （ETC） calculation, and point out that it may fail when applied to system where multiple weakly damped low frequency oscillation modes coexist. Then, a new Prony analysis based algorithm for ETC computation is proposed. The new algorithm inherits most merits of old algorithm such as being independent of models and parameters, at the same time it overcomes disadvantages of the old one. Finally, by means of the new algorithm, the relationship between electrical torque analysis and bifurcation analysis is demonstrated, so the essence of damping torque is revealed.