基于不完全S变换的低频振荡可视化实时监测方法

电网低频振荡的实时监测是有效控制低频振荡现象的前提。提出采用不完全S变换处理PMU实时数据,将隐含低频振荡信息的PMU数据波形图转换为直接显示各振荡模式下起振时刻、频率及振幅的二维时频图供调度人员参考,以实现低频振荡的可视化实时监测。为提高计算效率,采用GPU实现图形显示和不完全S变换中FFT及其逆变换的并行算法运算。实例分析结果表明,该方法能够有效识别并显示低频振荡实时特征信息,有助于调度人员进行低频振荡的实时监测,适合实际应用。

Visual real-time monitoring of low frequency oscillation based on incomplete S-transform

Visual real-time monitoring is the premise of low frequency oscillation control in power grids. This paper shows a visual method for the control center of power grids to monitor low frequency oscillation. It processes the PMU real-time data with incomplete S-transform, and converts the waveforms to two-dimensional time-frequency figures which shows the initial time, frequency and amplitude of each low frequency oscillation mode directly. GPUs are used to show figures and calculate FFT with the purpose of improving calculation efficiency. The results of practical cases show that the real-time characters of low frequency oscillation can be identified availably by this visualization real-time monitoring method which is helpful and suitable for practical application.