Realization Of Self-powered Parallel Synchronous Inductive Piezoelectric Vibration Energy Management Circuit

Due to most of the vibration in our environment have insufficient vibration intensity and low frequency,The output power is low.And the piezoelectric energy collector always output with alternating voltage,which can't directly supply to the wireless sensor node.We designed a self-powered parallel synchronous inductive piezoelectric vibration energy management circuit,which combined the P-SSHI circuit with the DC-DC management circuit to improve the energy conversion efficiency.First,The principle of standard energy collection circuit(AC-DC)?synchronous charge extraction circuit ? parallel synchronous switching inductance circuit(P-SSHI),series synchronous switching inductance circuit(S-SSHI)are analyzed.The relationship between the output power with the load are compared by Matlab simulation.The results show that using non-linear switching technology,the circuit's output power increased obviously,especially for P-SSHI.P-SSHI can obtain largest output power while in a wide range of output power and a small range of impedance.Therefore,this paper chooses the P-SSHI circuit as the charging circuit.And then,we designed an energy management circuit which based on parallel synchronous switching inductor circuit.The circuit improves the existing self-powered P-SSHI circuit.The number of devices is reduced without changing its function and the energy conversion efficiency is improved.Self-powered switch includes peak detector,comparator and synchronous switch.The output power of the improved circuit is twice as high as the pre-improved.At the same time,we designed the threshold setting circuit and step-down DC-DC conversion circuit.When sufficient energy is accumulated,energy will be translated to the load.By this way,the problem of impedance matching can be solved.The improved self-powered S-SSHI circuit is analyzed by Orcad / Pspice simulation.In the end,a complete piezoelectric energy management circuit is built,and simulated the vibration envelopment on the excitation table.At the same time,the energy management circuit based on LTC3588-1 and the standard energy management circuits are built and compared with the circuit designed in this paper.The experimental results show that the output power of the energy management circuit based on SSHI is the largest,which is 62%higher than that of the standard energy management circuit.And charge to the super capacitorneed less time and get more energy.This system supply power for thermistor sensor and wireless encryption receiver module.