Extensible piezoelectric energy harvesting circuit based on synchronous electric charge extraction with single inductor

Piezoelectric energy harvesting (PEH) is one of the effective methods to solve the limited power supply life of the wireless sensor network nodes. Most of the current research on piezoelectric energy harvesting is based on a single piezoelectric transducer (PZT). However, based on a single vibration source, multiple PZTs can be used to obtain more power. In response to this, an extensible piezoelectric synchronous electric charge extraction (E-SECE) circuit is proposed in this paper. The proposed circuit consists of several PEH cells, an inductor, a freewheeling diode and a storage capacitor, which can harvest energy from multiple PZTs with a higher inductor utilization. The detailed implementation of a self-powered double PZTs ESECE circuit is presented, and the theoretical analysis and simulation verify the superiority of the circuit. According to the simulation results, under the same excitation conditions, the output power of the E-SECE circuit with double PZTs can be up to 1.99 times that with single PZT, and the output power of single PZT E-SECE circuit can up to 3.08 times the maximum output power of standard energy harvesting (SEH) circuit.