Nonlinear fractional order derivative models of components and materials in hearing aids and transducers


Design of electroacoustic systems relies on accurate models of the components used. The response at low levels can be represented in the linear domain using lumped parameter models, where it is straightforward to include viscoelastic effects of materials, and lossy inductances. However, linear system analysis is rarely sufficient in finding the optimal solution. Therefore, understanding the nonlinear behavior of components and systems is required.


Currently, there is a gap between the advanced linear lumped parameter models, and the nonlinear models, which rely on simpler descriptions of materials and components. The project aims to develop robust and efficient nonlinear models that are able to predict the frequency dependent behavior of materials and components. This will be done using fractional order derivative models, which have shown promising results in the linear domain.


The models developed are expected to give a significant increase in modelling capability and accuracy, while improving system performance in terms of size, efficiency and cost.


Completed in 2019



Alexander Weider King
DTU Chemical Engineering
7 APRIL 2020