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This paper aims to investigate the efficiency of a laminated composite for shielding applications. The solution has to be efficient not only for the shield against static magnetic fields but also “for low-frequency ones, in order to be well-suited for applications with electromagnetic perturbations in the frequency range DC to 100 kHz.”

The composite constituted of a steel sheet taken in a sandwich between two aluminum (Al) sheets is produced by cold roll bonding. A good adherence between Al and steel sheets, ensuring a good mechanical resistance, is obtained with a specific process. A previous study has shown that the optimal trade-off between adherence and magnetic shielding effectiveness (SE_H) is obtained with a 230 µm composite produced with an initial thickness of Al and steel sheets, respectively, of 250 and 100 µm. In this paper, the 230 µm Al/steel/Al composite is used in three applications modelized by two-dimensional numerical simulations. To obtain reasonable computation time for the simulations, a homogenization method is applied to the composite. Studied applications are a cylindrical box containing a coil, a square box under an external magnetic field and a high voltage cable.

In each application, SE_H is calculated at low frequency and different materials (Al/steel/Al, Al, steel and copper) are compared. It is observed that, in each application, the composite presents higher SE_H at equal mass, especially for frequencies between 5 and 100 kHz.

The proposed approach, from the material point of view to the system consideration, shows that the thin bimetallic composite is an innovative and promising solution for magnetic shielding in the case of applications with both DC and low-frequency perturbations.

This paper seeks to study the feasibility of a stator vibration damping using piezoelectric (PZT) actuators applied to switched reluctance motors (SRM).

A single‐phase structure without moving rotor, but with the same shape as an SRM stator, is introduced to simplify the study and the experimental measurements. Both analytical and finite element methods are used to detail the chosen location and design of the PZT actuators for this structure.

Experimental results show that PZT actuators with a low voltage allow the decrease of the vibration level due to the electromagnetic forces.

To decrease the vibration level of the SRM stator in the real use of the machine, a closed loop system is necessary. Future works consist of the design of a closed loop numerical controller using an acceleration sensor as strain information.

The proposed damping method gives a new solution for the SRM noise problem that can be useful for people working on noise reduction on this machine.

So far vibration damping of SRM stator was obtained using a command or a geometry “acoustically” optimised, or active vibration with an auxiliary coil. The solution presented here applies PZT vibration damping to the stator with a thickness more important than the one of classical plates used for PZT damping applications.