Electromagnetic restoring forces in low energy electromechanical vibration generators

The paper describes the theoretical and experimental studies of the electromagnetic restoring forces in low energy electromechanical vibration generators (EMVG) with moving permanent magnet inductor. The mathematical model of electromagnetic field was obtained. The computational method based on magnetic circuit approach is developed and verified with the finite-element analysis. Experimental set and method are designed. Experimental results are given for electromagnetic force as a function of displacement of inductor. Based on experimental and theoretical studies, it has been shown that the electromagnetic restoring force can be assumed linear in a certain range of displacements (from 11 to 15 mm for tested prototype).