Performance investigation of piezoelectric-mechanical electromagnetic compound vibration energy harvester for electric tractor

The electric tractor belongs to off-road vehicle and often travels on the rugged ground generally featured as the Class-D Road which leads to large vibration. Currently, this kind of vibration energy has not been effectively recovered and utilized which results in energy waste. To address this problem, a novel piezoelectric-mechanical electromagnetic compound vibration energy harvester (P-MECVEH) was proposed. Then, the 10 DOF nonlinear dynamic model of the P-MECVEH was established, and its energy nonlinear dynamic characteristics were revealed numerically through the global bifurcation, phase orbit, Poincare & PRIME; map and FFT spectrum. The results showed that the energy output response of the P-MECVEH presented a high-energy period-2 state within the ranges of the excitation frequency f & ISIN; [2.475, 2.850 Hz] and amplitude Am & ISIN; [0.00644, 0.01000 m]. Finally, the reliability of the established dynamic model was verified through comparative analysis between the prototype experimental and theoretical results, and it was shown that the prototype generated a maximum output voltage of 38 V and a peak power of 14.44 W at a load resistance of 100 & omega; under the excitation frequency of 2.42 Hz and amplitude of 0.002 m, which indicates that the P-MECVEH has the potential in vibration energy recovery and utilization for electric tractors.