An electrostrictive model for polypropylene capacitors including intermediate layer polarization

In power electronics for electrical drivetrains, DC-link film capacitors are exposed to high ripple voltages. These voltages lead to electromechanical forces inside the dielectric of the capacitor which may result in acoustical noise emission. Therefore, an analytical model for calculating the electrostrictive deformation of polypropylene including intermediate layer polarization is presented. Numerical finite-element simulations are further accomplished and are validated with laser vibrometer and atomic force microscopy measurements.