Development and application performance of road spring-type piezoelectric transducer for energy harvesting

Abstract

Piezoelectric pavement energy transducers have attracted attention because they can directly convert mechanical energy into electric energy, thus enabling environmental protection, energy regeneration, and high energy output. However, existing piezoelectric transducers used in pavements made of piezoelectric ceramics are brittle and have short lives under long-term vehicle loading fatigue. In the present study, to raise the efficiency of energy harvesting, a new road piezoelectric transducer with a specified flexibility was designed and fabricated with two types of structures, plane and spring types, and their output performances were evaluated and compared. The test results showed that at the excitation frequency of 10 Hz and test displacement of 2 mm, the maximum output power of the spring piezoelectric energy harvester reached 14.183 mWmax for a matching resistance of 1 kΩ, and the output power was 2.24 times that of the plane piezoelectric energy harvester. Then, a fatigue test under an excitation frequency of 10 Hz and testing displacement of 2 mm was performed for the durability of the road spring-type piezoelectric transducer unit, and results showed that the piezoelectric transducer has a good durability and meets the general conditions for road engineering. Finally, the road spring-type piezoelectric energy harvester was tested on an actual road. When a pickup truck drove at a speed of 40 km h−1, the output power of the spring piezoelectric energy harvester reached a maximum of 592.77 mWmax for a matching resistance of 3 kΩ. Thus, this spring-type piezoelectric harvester can be ideally applied in road traffic.