三相不平衡高频振荡的相量测量方法

实时测量高频振荡相量可为高频振荡自适应抑制环节提供信息支撑.然而,高频振荡频率处正负序都可能存在不稳定模式,从而导致振荡信号三相不平衡特征明显,影响高频振荡相量测量准确度.因此,提出一种基于sinc插值函数的高频振荡相量测量方法.首先,对系统三相信号进行Clark变换;然后,基于sinc插值函数对负序振荡分量进行建模,进一步求解得到高频振荡相量和频率;最后,通过采用数值仿真信号、PSCAD仿真数据和实测数据进行测试发现,所提方法比传统方法具有更好的负序分量干扰抑制能力,准确度更高.

Phasor Measurement Method for Unbalanced Three-phase High-frequency Oscillation

Real-time measurement of high-frequency oscillation (HFO) phasors can provide the information support for adaptive suppression of HFOs. However, there may be unstable modes in both positive and negative sequences at the HFO frequency, which results in the obvious unbalanced three-phase characteristics of the oscillation signal and affects the measurement accuracy of HFO phasors. Therefore, an HFO phasor measurement method based on the sinc interpolation function is proposed. First, the system three-phase signal is transferred by Clark transform. Then, the negative sequence oscillation component is modeled based on sinc interpolation function to further solve the phasor and frequency of HFOs. Finally, by using numerical simulation signals, PSCAD simulation data and measured data, it is found that the proposed method has better interference suppression ability against negative sequence component and higher accuracy than the traditional method.