With the rapid advancement of intelligent road infrastructure, wireless sensors have become essential components of smart transportation systems. However, their widespread deployment is limited by the challenge of stable and long-term energy supply. To address this, a piezoelectric self-powered device for asphalt pavement is proposed, enabling efficient conversion of vehicle-induced mechanical energy into electrical energy. Using PZT-5H ceramics, single-, double-, and triple-layer stacked transducers were designed. The transducer was analyzed theoretically and through finite element simulation, with rutting tests simulating vehicle loading to assess output voltage and power under impedance matching. Capacitors with different capacitance values were tested for storage efficiency. A low-power wireless transmission circuit was also designed to assess the feasibility of driving wireless modules with harvested energy. Results show that stacking layers enhances energy harvesting efficiency. Under a 0.7 MPa load, a three-layer transducer produced 8.3 V and 31.4 μW, while five units charged a 220 μF capacitor to 3.3 V after 550 vehicle passes. Wireless tests showed that the peak-power during transmission reached 106.2 mW, with an energy consumption of 21.3 mJ for each peak transmission phase. This study provides a technical reference for self-powered wireless sensing in smart roads.
