The performances of piezoelectric transformer for fluorescent T5 lamp

The properties of circular type piezoelectric transformer for fluorescent T5 lamp are investigated as a function of area ratio of input part to output part. From the simulation result using FEM, as the area ratio increases, the voltage step-up ratio increases linearly. The voltage step-up ratio of output to input is about 1.6 when the area ratio is about 2. The new ballast using piezoelectric transformer is the type of series resonant half bridge inverter. As the results of performance test, when the input voltage is 220 V-rms, the step-up ratio is about 1.6 for fighting the lamp. Also, lamp current and output power are 150 mA and about 26 W in steady state, respectively. The efficiency is about 93 %. It is concluded that the PT fabricated in this study is available to the ballast for T5 lamp.