Detailed analysis and optimized design of piezoelectric energy harvesting circuit

The synchronized switch harvesting on inductor (SSHI) interface circuit can greatly enhance the output power of the piezoelectric harvesting system and therefore has been investigated extensively. Yet, the influences of the inductor L and the closing duration time τ_on of the switch S on the output power of the SSHI interface circuit have not been pointed out. The design constraints on L and τ_on imposed by the non-idealities in the SSHI circuit, the piezoelectric element and the load have been overlooked in the past researches. This paper tends to solve these issues and to carry out a detailed analysis. Some useful laws for SSHI interface circuit design considering the non-idealities in the non-linear processing circuit, the piezoelectric element and the load have been found.