A novel power generator in the tire which is applied in a wireless Tire Pressure Monitor System(TPMS) was designed. The piezoelectric convertor constructed by bender arrays was merged to the inner surface of a tire to transform the mechanical deformation into the electric power and supply to the sensors of TPMS. A Finite Element Model(FEM) for the convertor was established based on the second piezoelectric function and the piezoelectric convertor with different sizes was analyzed by ANSYS 11.0 in a transient method. Then

a target of 6 cm

2

was selected to observe its characteristics

and the effective current is 5 μA. As the wireless sending component needs 10 mA every 30 s

an array with 40 piezoelectric convertors was used in the generator and a power conditioning circuit with a multiple path charge coupling module was also designed. Experiments show that when the frequency of tire rotation is 15 Hz

the average power through the conditioning circuit is 150-350 μW and the instantaneous power can reach 50 mW

which proves that the power generator can work efficiently.