PIEZOELECTRIC ENERGY HARVESTERS FOR RAILWAY TRACK VIBRATIONS: A REVIEW OF STRUCTURAL DESIGNS AND PERFORMANCE ENHANCEMENT STRATEGIES

Abstract

Wireless sensors deployed along railway infrastructure are commonly powered by batteries, whose replacement can be costly, particularly on remote sections. Track vibrations induced by passing trains represent a local source of mechanical energy that can be converted into electrical energy using piezoelectric harvesters. This paper reviews structural configurations for railway track applications, including cantilever beams, piezoelectric stacks, and arched and ring-shaped structures. Methods for improving performance, including resonance tuning, broadband operation, frequency up-conversion, mechanical amplification, and overload protection, are examined. Representative designs are compared in terms of mounting location, excitation conditions, and output power.