Application of correlation function method integrated with frequency information to measurement of dielectric loss

Dielectric loss calculated by correlation function method has large error when signal frequency is different from power frequency. For improving the accuracy, modified correlation function method integrated with frequency information is presented. Hanning windowing interpolation algorithm is used to acquire signal frequency, integral period signal is gotten based on the signal frequency and the parabolic interpolation formulas. The modified correlation function method based on Simpson formulas is used to calculated dielectric loss. Dielectric loss of simulation signal is calculated by the original algorithm and the improved algorithm, the result indicates that the accuracy of the improved algorithm is much higher than that of the original one, the maximal error decrease from 10(-2) to 10(-4) after using of the proposed algorithm when the signal frequency is in the range of 49 to 51 Hz, so the algorithm can alleviate error caused by frequency fluctuation effectively.