Vibration energy extraction method of power transformer based on PMN-PT piezoelectric ceramics with series and parallel configuration

In order to realize the passive vibration monitoring of power transformer, a vibration energy extraction method of power transformer based on PMN-PT piezoelectric ceramic series and parallel structure, is proposed in this paper. The piezoelectric chip collects the vibration energy of the power transformer and converts it into electrical energy to supply power to the low-power vibration sensor. At the same time, the vibration sensor collects the surface vibration signal and uses the vibration analysis method to judge the operation status of the iron core and winding. The experimental and simulation results showed that the center frequency of the vibration signal of the power transformer was concentrated at 200 Hz, and the vibration amplitude of the lower part of the transformer was the largest; The actual output power of the piezoelectric energy collection device was greater than 500 µW. The energy recovery control circuit could greatly improve the energy recovery power, and the maximum output power was independent of the load. It could stably provide 3.6 V voltage for the back end, which was enough to meet the power supply demand of the vibration sensor.