Simulation and Analysis of a Novel Spiral-shaped Piezoelectric Energy Harvester under Multi-direction Excitation

Designing energy harvesters capable of operating at low frequencies and across a broad bandwidth is a key challenge in vibration energy harvesting. This paper presents the structural design, finite element modeling, and performance analysis of a novel spiral-shaped piezoelectric energy harvester (PEH). An electromechanical coupling model is built through the finite element analysis method to evaluate the electromechanical response of the proposed PEH under harmonic excitation. Modal analysis reveals that the first three resonant frequencies of the proposed structure are closely spaced, enhancing its capability for broadband energy harvesting in the low-frequency range (15–30 Hz). Frequency response analysis demonstrates that different excitation angles significantly affect the voltage and power output. At an excitation angle of 112.5°, the energy harvester achieves a maximum output power of 244 μW under an excitation level of 0.1g. These findings highlight the potential of the proposed PEH design in low-frequency vibration energy harvesting applications.