Experimental investigation on a Fe-Ga close yoke vibrational harvester by matching magnetic and mechanical biases

The results here obtained point out that it is possible to simplify the design of magnetostrictive energy harvesters and to obtain high output power even with permanent magnets providing a relatively small coercive field. The results have been confirmed by using two yokes equipped with permanent magnets on the external columns. The maximum output average power obtained with permanent magnets has been 796 mW equal to 6.5 mW/cm3 with a sinusoidal vibration amplitude of 40 MPa at 100 Hz.