Düşük profilli doğrusal olmayan anahtarlama tekniğikullanan tam otonom piezoelektrik enerji üreteci arayüz devresi

Energy scavenging from ambient vibration sources via piezoelectric transducers offers a promising solution to power microelectronic devices. Energy extraction from harvesters is conducted with full-bridge rectifiers (FBRs) whose performances are affected harshly due to intrinsic capacitance of harvester requiring continuous charging. Conventional nonlinear switching techniques proposed in literature overcome problems associated with standard AC/DC converters. Nonetheless, they require large external components to achieve decent conversion efficiencies and output powers. This obstructs miniaturization trend in micro-fabricated wireless sensor networks and limits their application area. The aim of this work is to implement a low-profile autonomous interface circuit that can harvest energy from MEMS piezoelectric transducers and deliver power to electronic loads. In the first design, a unique low-cost fully autonomous interface circuit using novel SSHCI technique is proposed to reduce overall system volume. New two-step voltage flipping with optimal flipping time detection enables Synchronized Switch Harvesting on Capacitor-Inductor (SSHCI) circuit to use inductors in the range of tens of 􏰂micro-H􏰆s for voltage flipping. This shrinks system volume significantly. Fabricated IC is able to attain 6.14x output power improvement over ideal FBRs and 90.1% power conversion efficiency. Secondly, maximum power point tracking (MPPT) circuit integrated with SSHCI is implemented to eliminate load dependency. Inductor sharing between SSHCI and MPPT allows them to employ the same low-prolife inductor for operation which decreases system cost. Occasional refreshment of optimum battery voltage sensing makes system invulnerable to input excitation changes of PEH. SSHCI-MPPT achieves 5.44x power extraction improvement and 83% efficiency while providing load independency.