周期性负荷扰动下电网及弹簧网强迫功率振荡分析

Forced power oscillation analysis of power grid and spring network under periodic load disturbance

针对周期性负荷扰动下的电网振荡特征,文中提出了一种通过映射弹簧网获取系统振荡模态信息的方法。通过分析单机和多机系统及单自由度和多自由度弹性系统的数学模型,确定了电网与弹簧网模型之间的映射关系,然后在此基础上推导了周期性负荷引发系统强迫功率振荡的机理。当负荷出现周期性扰动,且扰动频率接近或等于系统固有振荡频率时,会诱发系统产生强迫功率振荡。算例分析进一步验证了电网与弹簧网之间的振荡模态具有一致性。该方法为研究低频振荡提供了一种新的思路,具有一定的参考价值。

Aiming at the characteristics of grid oscillation under periodic load disturbance, a method for obtaining oscillation modal information of the system by mapping spring network is proposed in this paper. Firstly, the mapping relationship between power grid and spring network model is determined by analyzing the mathematical models of single machine and multi-machine systems and single degree of freedom and multi-degree of freedom elastic systems. And then, the mechanism of forced power oscillation caused by periodic load is deduced. When the load is periodically disturbed and the disturbance frequency is close to or equal to the natural oscillation frequency of the system, it can induce the system to generate forced power oscillation. Finally, the example analysis further verifies the consistency of the oscillation modes between the power grid and the spring network. This method provides a new idea for studying low frequency oscillation and has certain reference value.