Non-contact piezoelectric–electromagnetic hybrid generator for hydrological monitoring systems†

Water resources are some of the most abundant natural resources in the world, and their rational development, utilization and monitoring are becoming increasingly important. This paper presents a non-contact piezoelectric–electromagnetic generator (P-EHG) for hydrological monitoring. The device was divided into a piezoelectric self-powering module and electromagnetic sensing module. Adopt space gear set system in the structure to realize multi-frequency bidirectional excitation of the piezoelectric element and electromagnetic component. Experimental system configuration was utilized to investigate the impact of the height of the magnet, the force-bearing position in the PEG, and the polarity of the excitation rod magnet on the output performance of the P-EHG. The highest voltages that could be produced by a single PEG and EMG when the P-EHG was built with the ideal structural characteristics were 59.88 V and 831 mV, respectively. The maximum output power of the single PEG and EMG was 10.121 mW and 0.01036 mW, respectively, and the maximum output power of the hybrid was 12.288 mW. Thus, the power output of the hybrid was 21.4% higher than that of the PEG and 118 510% higher than that of the EMG. Subsequently, the application of the P-EHG was demonstrated and verified in an actual water environment to prove its self-powering and self-sensing capabilities as a hydrological monitoring system. This provides a basis for resource monitoring in deep seas, oceans, and rivers.