Ambient vibration energy collecting device based on two-DOF (Degree of Freedom) piezoelectric vibrator

Abstract

The invention discloses a ambient vibration energy collecting device based on a two-DOF (Degree of Freedom) piezoelectric vibrator which comprises two parts, namely energy conversion and power regulation, wherein an vibration unit containing piezoelectric material in a vibration energy conversion device can respond ambient vibration transmitted by a base and convert mechanical energy into electric energy; a power regulation circuit accumulatively store electric energy after extraction and regulation. The vibration unit is provided with two piezoelectric vibrators with SDOF (Single Degree of Freedom) cantilever beam structure, which are fixed on the base in parallel horizontally, and a spring vertically connected with a vibrator mass block; the beam thickness of the two vibrators and the weight of the mass block are different, thus a broadband resonance two-DOF system of which adjacent first-order resonance frequency and second-order resonance frequency are adjacent is formed. The power regulation circuit is provided with a low-power-consumption synchronous charge transfer circuit module, a charge collection capacitor, a controllable voltage threshold DC / DC (direct current) conversion module and a power storage component. The device has a broader resonance response frequency band and low power consumption, can work without an external power supply so as to achieve high efficiency, and is suitable for self-powered devices or devices getting electrical energy supply from environment.

Description

technical field [0001] The invention relates to a micro-miniature device for collecting environmental vibration energy based on a two-degree-of-freedom piezoelectric vibrator, which is suitable for applications such as wireless sensors and portable electronic devices that require self-power supply or energy supplementation by collecting vibration energy of the surrounding environment occasion. Background technique [0002] With the rapid development of low-power, self-contained systems such as wireless sensor networks and portable electronic devices or devices, the need for long-life independent power supply technologies is becoming more and more intense. At present, the battery is still the preferred power source for this type of system, but the battery capacity is limited after all, and it needs to be replaced regularly, which brings great inconvenience to the application of the above-mentioned system. At the same time, the extensive use of disposable batteries can also c...

AI Technical Summary

Problems solved by technology

At present, foreign scholars have designed a vibration energy harvesting device with a wider frequency band by using the technologies of pre-applying axial stress and utilizing the change of capacitive load to realize frequency control, but the structure of the device is complicated, the cost is high, and the energy efficiency is low.

[0005] Summarizing the existing technology, it can be found that the resonant operating frequency band of the single-degree-of-freedom piezoelectric vibration energy harvesting device is narrow, and it is difficult to meet the application requirements of high-efficiency energy harvesting; Vibration energy harvesting device has complex structure, low energy conversion efficiency and poor practicability

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