A Time-Multiplexing Multi-Input Hybrid Harvester with Low-Power MPPT Technique

Abstract

This paper presents a multi-input hybrid energy harvesting system that collects maximum energy from multiple sources using a low power maximum power point frocking (MPPT) controller. The proposed MPPT controller performs a real-time MPPT with an incremental conductance (INC) method while reducing its power consumption and the limit cycle behavior near the lock point by prudently scheduling the active and idle times. The proposed harvesting system is prototyped with discrete components, including a programmable microcontroller and non-volatile memory (NVM) programmable device. The experimental results show that the MPPT controller can achieve a low average power consumption of 153nW at steady-state with a peak frocking efficiency of 99.6%, improving the peak harvesting efficiency of the overall system from 79% to 87%.