微弱次同步振荡模态参数的在线实时辨识方法

发布时间：2018-05-15 20:17

本文选题：次同步振荡 + 微弱信号　；参考：《中国电机工程学报》2017年S1期

【摘要】：提出一种基于环境噪声激励响应的微弱次同步振荡模态参数在线辨识方法。将其用于电力系统正常运行中的转子旋转振动响应和电网侧电气响应,从中提取出反映次同步振荡各模态特征的单自度自由响应分量;进而利用Ibrahim时域模态辨识法计算出各模态的频率和阻尼系数等参数。研究了用于获取自由响应分量的随机减量技术的关键参数,给出门槛值和子样本长度的推荐值,从而提高了模态阻尼的辨识精度。通过对多模态微弱响应信号进行模态预分离,从而保证幅值相差很大时的小幅值模态无缺失,提高了模态辨识的可靠性。利用上述方法和步骤,从新疆哈密地区机网正常运行中的环境激励响应中辨识出微弱次同步振荡模态的阻尼因子等参数,并实现对模态阻尼趋势的在线连续实时辨识,尤其在当前大规模新能源并网背景下,能够及时发现影响系统稳定运行的关键环节,为切实做好广域动态稳定工作奠定基础。
[Abstract]:An on-line identification method of weak subsynchronous oscillation modal parameters based on ambient noise excitation response is proposed. It is applied to rotor rotation vibration response and grid side electrical response in normal operation of power system, and the single self free response component which reflects the characteristics of each mode of subsynchronous oscillation is extracted from it. Then the frequency and damping coefficient of each mode are calculated by Ibrahim time domain modal identification method. The key parameters of random decrement technique for obtaining free response components are studied, and the threshold values and the recommended values of sub-sample length are given to improve the identification accuracy of modal damping. The multi-modal weak response signal is preseparated to ensure that there is no missing of the small mode when the amplitude is very different and the reliability of modal identification is improved. Using the above methods and steps, the parameters such as damping factor of weak sub-synchronous oscillation mode are identified from the environmental excitation response of the machine network in Hami area, Xinjiang, and the on-line continuous real-time identification of modal damping trend is realized. Especially under the background of large-scale new energy grid connection, the key links that affect the stable operation of the system can be found in time, which lays the foundation for doing well the work of wide area dynamic stability.
【作者单位】：北京信息科技大学自动化学院;北京四方继保自动化股份有限公司;
【基金】：国家自然科学基金项目(51477010)~~
【分类号】：TM712

【相似文献】