A Universal Method for Frequency Domain Response Curve Decomposition and Its Application

The performance of dielectric material affects its dielectric response under alternating electric field, which makes the dielectric response technology being a widely-used method in the performance evaluation in insulating materials. The current research on dielectric response is limited to summarizing experimental rules and building mathematical models, which is due to the lack of composition analysis and mechanism interpretation of dielectric response curve. In this paper, a general mathematical method is proposed for the spectrum curve decomposition and composition analysis of nonideal dielectric medium in the frequency domain. Considering the simple Debye model, a functional relationship between the imaginary part of complex permittivity and the derivative of the real part with respect to the angular frequency is established. And then, the imaginary part spectrum curve of nonideal dielectric medium can be decomposed. The test and analysis of the oil-paper complexed material show that, the imaginary part spectrum curve of complex permittivity of oil paper insulation material is decomposed into two parts: conductivity loss curve and polarization loss curve, that are in line with relaxation polarization theory. It provides a mathematical means for mechanism analysis and further application of the frequency spectrum curve of nonideal dielectrics.