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In this paper, common mode (CM) conducted perturbations are predicted and compared with experiments in a variable-speed drive system, thanks to a mixed approach based on experimental measurements and on the modeling of the complete CM circuit. Its different parts are considered and represented by a chain of quadripolar matrices: the inverter, the cables, and the induction motor. At last, it is shown that the parasitic currents in the system can be calculated in the different stages of the matrix chain. Experiments have successfully confirmed this approach.

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In this paper we investigate the capability of harvesting the electric energy from mechanical vibrations in a dynamic environment through a unimorph piezoelectric membrane transducer. Due to the impedance matrices connecting the efforts and flows of the membrane, we have established the dynamic electric equivalent circuit of the transducer. In a first study and in order to validate theoretical results, we performed experiments with a vibrating machine moving a macroscopic 25 mm diameter piezoelectric membrane. A power of 1.8 mW was generated at the resonance frequency (2.58 kHz) across a 56 k optimal resistor and for a 2 g acceleration.

The rapid development of low power consumption electronics and the possibility of harvesting energy from environmental sources can make totally autonomous wireless devices. Using piezoelectric materials to convert the mechanical energy into electrical energy for batteries of wireless devices in order to extend the lifetime is the focus in many researches in the recent years. It is important and efficient to improve the energy harvesting by designing an optimal interface between piezoelectric device and the load. In this paper, a self-powered piezoelectric energy harvesting device is proposed based on the velocity control synchronized switching technique (V-SSHI). Comparing to the standard full bridge rectifier technique, the synchronized switching harvesting on inductor (SSHI) technique can highly improve harvesting efficiency. However, in real applications when the energy harvesting device is associated with wireless sensor network (WSN), the SSHI technique needs to be implemented and requires being self-powered. The conventional technique to implement self-powered SSHI is to use bipolar transistors as voltage peak detector. In this paper, a new self-powered device is proposed, using velocity control to switch the MOSFET more accurately than in the conventional technique. The concept of design and the theoretical analysis are presented in detail. Experimental results are examined.

A new non-isolated low-power inductorless piezoelectric resonant converter is presented. The piezoelectric material is used as an energy storage element like an inductance in a classical Buck-Boost power electronic converter. As opposed to most existing piezoelectric converters, the proposed topology enables to dynamically adjust the output power and ratio keeping a high efficiency for a large range of output powers and for a large range of conversion ratios taking advantage of piezoelectric high quality factor and achieving zero voltage switching. A theoretical analysis of the step-up converter using an energetic approach is introduced and enables a fast and reliable pre-design of the piezoelectric component. This analysis is in perfect agreement with the simulation model performed on Matlab/Simulink. For a given piezoelectric resonator both analytical and simulation models provide very high efficiencies for different output powers. The converter is tested experimentally with a 10 V input voltage using the piezoelectric radial resonance mode. An efficiency higher than 98% for a 160 mW power conversion was achieved, decreasing slowly to 78% at 1.4 W. For a large range of voltage gains, the efficiency remains higher than 90% up to an output power of 750 mW. The experimental results are in perfect agreement with the theoretical analysis until 500 mW.

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