摘要
采用FFT谐波分析方法进行介质损耗角测量时,由于非同步采样会导致频谱泄露和栅栏效应,给介质损失角测量带来较大误差。为提高介损测量精度,文中提出基于Nuttall窗的三谱线插值介损测量方法。通过加Nuttall窗进行FFT得到离散序列,由三谱线插值进行频谱校正得到电压电流基波相位,根据两者相位差来计算介质损耗角。在基波频率波动、三次谐波含量变化、白噪音存在和采样点数变化的情况下测量介损角。仿真分析结果表明,Nuttall窗具有良好的旁瓣性能,能更好抑制频谱泄露,减小测量误差,所提方法测量介质损耗角时具有较高计算精度。
As the dielectric loss angle calculated by the FFT harmonic analysis method,it has larger error due to the asynchronous sampling which will cause spectral leakage and hurdle effect.In order to improve the accuracy of dielectric loss angle measurement,this paper proposed a method for dielectric loss measurement based on Nuttall window of three spectral lines interpolation.The discrete sequences are obtained by adding Nuttall window,and the fundamental phase of voltage and current is measured by three spectral lines interpolation,and then,the dielectric loss angle is calculated according to the phase difference.The dielectric loss angle is calculated by the proposed method under different conditions,such as fundamental frequency fluctuation,harmonic ratio variation,variation of sampling points and white noise.Simulation results showed that Nuttall window has a good side-lobe performance and inhibit the spectral leakage to reduce the measurement errors.The proposed method of dielectric loss angle measurement has high calculation accuracy.
作者
李媛
王海云
Li Yuan;Wang Haiyun(School of Electrical Engineering,Xinjiang University,Urumqi 830047,China)
出处
《电测与仪表》
北大核心
2018年第17期15-20,共6页
Electrical Measurement & Instrumentation
基金
国家科学自然基金资助项目(51667020)
自治区重点实验室开放课题(2016D03021)
