提高介质损耗因数监测准确度的算法

为解决在电气设备介质损耗因数的计算中必须严格满足同步采样条件和计算分辨率低的问题,基于Hilbert变换和复三角函数运算,提出了一种提高介质损耗因数监测准确度的数字化算法,并给出了算法的理论基础。仿真结果表明:该算法在电网频率存在波动以及采样数据长度为非整数周期等情况时具有良好的应用特性,较好地解决了实际信号量测中存在的非同步采样问题。该算法对电网电压中谐波含量的存在并不敏感,当谐波含量在10%以下时,可获得小于1%的计算准确度。

Robust algorithm for accurately monitoring the dielectric loss factor

Most present digital algorithms for on-line monitoring of the dielectric loss factor in power equipment are limited by the assumption of the synchronous sampling criterion which reduces the calculational resolution. This paper describes the use of Hilbert transforms and complex trigonometric operations in a digital algorithm that improves the monitoring accuracy of dielectric loss factors. Simulation results show that the algorithm performs well even with power frequency fluctuations or when the sampled data length is not exactly an integral multiple of the power cycle to effectively solve the issues incurred with asynchronous sampling. In addition, the algorithm is insensitive to harmonics in the power voltage signals, with an accuracy of better than 1% when the harmonics are less than 10% of the power voltage.