A Piezoelectric Vibration Energy Harvesting System Capable of Tracking Maximum Power Point

Abstract

The invention discloses a piezoelectric vibration energy collection system capable of tracing maximum power point. In the piezoelectric vibration energy collection system, a self-power supply SSHI-type AC-DC rectifier is used for converting an alternating current output from a piezoelectric transducer into a direct current, the direct current is output to a first capacitor, a hysteresis comparisoncontrol and working power supply selection circuit is used for controlling whether a PWM wave generation and working mode selection circuit enters a working condition or not, the PWM wave generationand working mode selection circuit is used for controlling a working mode of the dual-switch Buck-Boost type DC-DC converter, the first capacitor is controlled to be discharged when the dual-switch Buck-Boost type DC-DC converter enters the working condition, a second capacitor is charged, a voltage loaded onto the first capacitor is maintained around an optimal value, and tracing of maximum powerpoint is achieved. The piezoelectric vibration energy collection system has the advantage of relatively high vibration energy collection efficiency.

Description

technical field [0001] The invention relates to a piezoelectric vibration energy collection system, in particular to a piezoelectric vibration energy collection system capable of tracking the maximum power point. Background technique [0002] Mechanical vibration widely exists in the natural environment and human activities, and is a typical form of energy. The piezoelectric vibration energy harvesting system can capture the vibration energy generated by mechanical vibration, and finally convert the vibration energy into direct current that can be used by microelectronic devices for storage. The existing piezoelectric vibration energy harvesting system usually includes two parts: a piezoelectric transducer and an electric energy extraction circuit. The alternating current output by the energy converter is converted into direct current for storage. The piezoelectric transducer is a conventional device at present. After the piezoelectric transducer is determined, the perform...

AI Technical Summary

Problems solved by technology

These two piezoelectric vibration energy extraction circuits based on maximum power point tracking did solve the problems of load dependence and load mismatch. However, they both first used a full-bridge rectifier circuit to rectify the output AC of the piezoelectric transducer, and then Then carry out the maximum power point tracking control, resulting in the output power of the energy extraction circuit is always limited by the maximum output power of the full-bridge rectifier circuit under ideal conditions, and the efficiency of piezoelectric vibration energy collection is still not high

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