频谱泄漏抑制与改进介损角测量算法研究  

Study on spectral leakage suppression and improved dielectric loss angle measurement method

作　　者：温和[1,2] 滕召胜[1] 王永[1] 胡晓光[2] 叶红霞[1] 

机构地区：[1]湖南大学电气与信息工程学院,长沙410082 [2]北京航空航天大学自动化科学与电气工程学院,北京100191

出　　处：《仪器仪表学报》2011年第9期2087-2094,共8页Chinese Journal of Scientific Instrument

基　　金：国家自然科学基金(No.61002035;No.60872128);高等学校博士学科点专项科研基金(新教师类)(No.20100161120004);中国博士后科学基金(No.20100471213)资助项目

摘　　要：研究分析了非同步采样时频谱泄漏和栅栏效应对介损角测量误差的影响,提出了一种基于Hanning自卷积窗的改进FFT介损角测量算法。首先采用Hanning自卷积窗对电压电流信号加权,然后利用离散频谱插值算法和多项式拟合方法进行离散频谱校正,获得基波相位角,最后根据电压、电流基波相位差实现介损角测量。在非同步采样时,本文算法只需用4阶Hanning自卷积窗进行加权即可充分抑制频谱泄漏的影响,基于改进FFT的介损角插值计算式具有运算量小,易于实现的特点。基波频率波动、采样频率变化、白噪声影响、谐波变化等情况下的介损角仿真测量实验结果和实验室条件下的实际测量结果验证了本文算法的准确性和有效性。The effect of spectral leakage and picket fence effect on dielectric loss angle measurement error in nonsynchronization sampling was analyzed. An improved FFT algorithm for dielectric loss angle measurement based on the Hanning self-convolution window （HSCW） is presented in this paper. Firstly, the voltage and current signals are weighted using the HSCW. Then, the fundamental phase angles are calculated with discrete spectral interpolation and polynomial fitting methods. Lastly, the dielectric loss angle is obtained from the phase difference of fundamental voltage and current. The proposed method can suppress spectral leakage only using 4-order HSCW; and the dielectric loss angle calculation formula features low calculation burden and can be implemented easily. The simulation experiments for fundamental frequency fluctuation, sampling frequency change, white noise and harmonic component change were carried out ; actual measurement experiments under laboratory condition was also carried out. All of the experiment results have verified the effectiveness and practicability of the proposed method.

关 键 词：介质损耗 频谱泄漏 卷积窗 改进FFT 频谱校正 

分 类 号：TN911[电子电信—通信与信息系统] TM714[电子电信—信息与通信工程]