用于次同步振荡模态提取的柔性原子滤波

针对现有次同步振荡模态提取方法在模式分辨率、动态特性和抗噪声干扰能力等方面的不足,提出一种柔性原子滤波方法。该滤波器的时频域带宽柔性可调,能根据测量需要获取较高模式分辨率和快速动态特性。该方法在次同步频带设置滤波器,每个滤波器具有相同尺度因子和带宽参数,能在次同步频带通过滤波计算获取主导模式幅值包络线和频率,再利用最小二乘法从幅值包络线中提取各模式初始振荡幅值和衰减因子,进而获取阻尼比参数。Matlab仿真算例和基于EMTDC/PSCAD的IEEE第一标准测试模型算例证明了所提方法的正确性和有效性。仿真结果证明该方法能准确辨识频谱密集的复合振荡模态,准确跟踪时变性振荡频率,且具有较好的噪声鲁棒性。

Flexible Atom Filtering for Subsynchronous Oscillations Mode Extraction

The conventional subsynchronous oscillations (SSO) mode extraction methods have some shortages, such as lower mode identification, worse dynamic characteristics and poor anti-noise ability. Thus, this paper proposes a novel flexible atom filtering method, where the time and frequency window can be adjusted flexibly. Thus high mode identification and fast dynamic characteristics can be achieved. The central frequency of the filter is set within the SSO frequency scale. By filtering, the method can obtain the frequency and amplitude envelope curves. The least square method is deployed to get initial oscillation amplitude and attenuation factor. Matlab simulation cases and IEEE first benchmark cases in EMTDC/PSCAD have verified the correctness and effectiveness of the method. The simulation results have shown that the method can accurately identify the spectrum-intensive complex oscillation modes and time varying oscillations. The method is also robust to Gauss white noise.