Accession Number : ADA303833

Title :   High Power Electronics Institute, RF of SUNY 150-4758A (ONR2c).

Descriptive Note : Annual rept. no. 3, 15 Feb 95-15 Feb 96,

Corporate Author : STATE UNIV OF NEW YORK AT BUFFALO DEPT OF ELECTRICAL AND COMPUTER ENGINEERING

Personal Author(s) : Sarjeant, Jim ; Lee, George ; Laghari, Javaid

PDF Url : ADA303833

Report Date : FEB 1996

Pagination or Media Count : 17

Abstract : An investigation is conducted to study and model the aging of polypropylene, a widely used polymer dielectric in energy storage and transport devices, under the sequential application of thermal and DC electrical stresses. Continuous thermal aging in air was carried out at temperatures of 90 deg C and 110 deg C for aging times of 100, 300, and 500 hours. The DC lifetimes of the control (thermally unaged) and thermally aged films were then obtained at four voltage stress levels of 16, 15, 14 and 13 kV. Testing of a sufficiently large number of randomly chosen specimens in a well designed test plan allows for the analysis of all the effects of stress factors independently and interactively. A complete statistical analysis of the data included nonparametric and parametric assessment of adequate life distributions and life-stress models (linear and nonlinear) utilizing Least Squares and Maximum Likelihood regression methods. Several diagnostic tests, including Electron Scattering for Chemical Analysis (ESCA), Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), Fourier Transformed Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopy, Wide Angle X-ray Diffraction (WAXS), plus other mechanical and electrical characterizations including DC breakdown voltage, dielectric constant, dissipation factor, tensile stress and strain, and Young's Modulus, for the control and aged samples were carried out. Results were then compared to detect any correlating changes and interpreted in the light of available aging theories. jg p16

Descriptors :   *HIGH POWER, *ELECTRONIC EQUIPMENT, *POLYPROPYLENE, TEST AND EVALUATION, THERMAL PROPERTIES, SCANNING ELECTRON MICROSCOPES, NUCLEAR MAGNETIC RESONANCE, AGING(MATERIALS), LIFE EXPECTANCY(SERVICE LIFE), MODELS, SPECTROSCOPY, MAXIMUM LIKELIHOOD ESTIMATION, STRESS TESTING, TENSILE STRESS, ELECTRON SCATTERING, MODULUS OF ELASTICITY, X RAY DIFFRACTION, VOLTAGE, ELECTRICAL PROPERTIES, REGRESSION ANALYSIS, ELECTRON MICROSCOPY, DIELECTRIC PROPERTIES, PLANNING, LEAST SQUARES METHOD, TRANSPORT, POWER EQUIPMENT, STATISTICAL ANALYSIS, DIRECT CURRENT, ENERGY STORAGE, CHEMICAL ANALYSIS, WIDE ANGLES, BREAKDOWN(ELECTRONIC THRESHOLD), DISSIPATION FACTOR.

Subject Categories : Electrical and Electronic Equipment
      Physical Chemistry
      Polymer Chemistry
      Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE