一种介质损耗因数在线监测新方法

A Novel Method for Online Monitoring of Dielectric Loss Factor

应用传统方法对介质损耗因数进行在线测量存在许多内在的性能局限,包括同步采样、间谐波和电力系统频率必须保持不变等问题。在频率波动和间谐波都存在的非稳态信号环境下,采用传统方法不能保证测量的准确性。文章提出一种对电力设备介质损耗因数进行在线测量的高准确度改进方法。新提出的包括数据截断和数据叠加的数据处理方法,能够补偿数据频谱泄漏所引起的相位偏移,它能够准确地提取基波信号并计算介质损耗因数。数据仿真和实际工程测量结果表明,新方法不受以上所提局限的影响,具有良好的应用可行性。

There are many inherent performance limitations using traditional algorithms for online measurement of die-lectric loss factor,including synchronous sampling,no inter-harmonics and invariable power system frequency. In a non-stationary signal environment where power frequency fluctuation and inter-harmonic components exist,meas-urement accuracy with traditional methods cannot be guaranteed. The paper proposes a high-accuracy modified meth-od for online monitoring of dielectric loss factor of power equipment. The theoretical basis of the algorithm is based on a new data processing procedure including data truncation and data addition,which can compensate for the phase dis-tortion caused by spectrum offset of addition data. The algorithm can accurately extract the fundamental signal and cal-culate the dielectric loss factor. Measured results of simulations and practical engineering projects show that the new al-gorithm is feasible for application without limitations rendered above.