Research and design of downhole thermoelectric energy harvesting device

Abstract

In order to solve the problem of power supply of wireless monitoring node in coal mine working face， a thermoelectric energy harvesting device for the surface temperature difference of downhole equipment is designed based on the thermal electric generator(TEG) and boost management module in this paper. The device is used to charge the lithium ion battery. Experimental results show that the circuit can continue energy harvesting from input sources as low as 100 mV. The stable output power of TEG can be increased by several tens of times using air cooling or water cooling. The bq25505 device is specifically designed to efficiently extract the power generated from the TEG. It can significantly increase the discharge working time of the lithium battery, and the energy conversion efficiency of the module is up to 67%. Therefore, the device can effectively improve the working cycle of the downhole wireless node.

Keywords

• thermoelectric energy harvesting module
• thermal electric generator
• bq25505
• energy storage