Abstract:
This paper presents a modified Damage Equalization Method with statistical features
for life estimation of dielectrics. The paper postulates damage as a random variable,
which resulted in establishing a relationship between the Weibull scale, shape
parameters and the endurance coefficient ‘n’ of inverse power law. By the modified
DEM (m-DEM), for the first time, a range of values of n for each material is proposed,
which is useful for design engineers. Until now, the endurance coefficient of inverse
power law and strength constant were treated as constants. Here, it is shown that these
coefficients do have statistical features or variations. Experiments are conducted on oil
impregnated paper and LDPE samples using accelerated step-stresses for life
estimation. The results of the estimation of endurance coefficient are compared with
existing methods and reasonable conclusions are drawn in favor of the proposed
method.
