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To provide a model that allows testing and understanding special damping techniques.

The finite element modeling takes into account the piezoelectric coupling. It is used with a non linear electrical circuit. The approach leads to an accurate tool to observe the behavior of the non linear damping techniques such as synchronized switch damping.

The model has been validated by comparison with Ansys® but the CPU time required for the model is around one hundred times shorter.

The proposed model is 1D and the assumptions to use it are not verified for all structures.

The authors obtain a useful tool for the design of damping structures (for example to find the best localisation of the piezoelectric patches and to test electrical circuits).

The model is used for the design and conception of damping as well as for harvesting structures.

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.

This paper deals with the study of the influence of the phase shift between currents and back-electromotive forces (back-EMF) on torque ripple and radial magnetic forces for a low power synchronous machine supplied with 120 degrees square-wave currents. This paper aims to establish a good compromise between efficiency, harmonics of torque and harmonics of radial forces at the origin of the electromagnetic noise.

Based on a finite element approach, torque and magnetic pressure harmonics versus space and frequency are evaluated for different angle values. The evolutions of the different harmonics against the load angle are analyzed and compared to those of experimental measurements.

Depending on the load torque, field-weakening or field-boosting can be used to reduce current harmonics contributing the most to the radial magnetic forces responsible for the noise. Besides, a compromise can be found to avoid deteriorating too much the performances of the machine, thus being suitable with an industrial application.

This study concerns low power permanent magnet synchronous machines with concentrated windings and driven with a trapezoidal control, while having sinusoidal back-EMF.

The use of a simple mean and suitable with a large-scale manufacturing industry to reduce the identified electromagnetic-borne noise of a specific electric drive makes the originality.