Electrical and geometrical optimization for a 2DoF non-linear energy harvester

  • Frizzell R.

In this paper a non-linear model for a two degree-of-freedom (2dof) vibrational energy harvester is presented, together with its experimental validation. The device consists of two masses relatively oscillating one inside the other. The inner (lighter) mass comprises five NdFeB magnets, arranged in a Halbach configuration. The outer (heavier) mass is made of seven coils. Magnetic springs are placed on the top and on the bottom of the outside mass and of the inside mass respectively, in order to allow impacts between the two: this enables energy to be transferred from the heavier to the lighter mass, in order to amplify the velocity of the latter. In this way, a better ability to convert energy from small vibrations is reached using electromagnetic conversion, which is strongly affected by the relative velocity of the two masses. A finite element model is presented in order to simulate the magnetic field produced by the Halbach stack and the force of the springs as a function of the cap height. This results are then integrated in a numerical model built in Matlab, in order to study the electrical optimization for the harvester: the number of turns of the coils is varied, showing the power output produced at different frequencies. Finally, the same model is used with exponentially correlated noise as the input, and the effect of lowering the cap is introduced using the model of the springs. Experimental data are compared to the simulation results, demonstrating the effectiveness of the model.

Recent Publications

August 09, 2017

A Cloud Native Approach to 5G Network Slicing

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5G networks will have to support a set of very diverse and often extreme requirements. Network slicing offers an effective way to unlock the full potential of 5G networks and meet those requirements on a shared network infrastructure. This paper presents a cloud native approach to network slicing. The cloud ...

August 01, 2017

Modeling and simulation of RSOA with a dual-electrode configuration

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Based on the physical model of a bulk reflective semiconductor optical amplifier (RSOA) used as a modulator in radio over fiber (RoF) links, the distributions of carrier density, signal photon density, and amplified spontaneous emission photon density are demonstrated. One of limits in the use of RSOA is the lower ...

July 12, 2017

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How to preserve users' privacy while supporting high-utility analytics for low-latency stream processing? To answer this question: we describe the design, implementation and evaluation of PRIVAPPROX, a data analytics system for privacy-preserving stream processing. PRIVAPPROX provides three properties: (i) Privacy: zero-knowledge privacy (ezk) guarantees for users, a privacy bound tighter ...