Abstract
This work presents energy harvesting techniques from low-voltage current used to prevent galvanic corrosion between a metallic structure and a permanent copper/copper sulfate (Cu/CuSO4) reference electrode. Supercapacitors are adopted to compensate for or overcome the limitations of batteries. Then, a boost converter is used to convert the low voltage levels of galvanic corrosion to that needed by the complementary metal oxide semiconductor (CMOS) technologies used for the wireless sensor systems. Experimental results show that our proposed harvesting schemes significantly reduce the overhead of the charging circuitry, which enables nearly full charging of supercapacitors of up to 350 F under the low power conditions of 3mW (i.e., 3mA at 1 V). More importantly, our system enables maintenance-free operation of remote-monitoring cathodic protection (RMCP) systems in harsh environments, where sunlight or wind power may be unavailable or unpredictable.