Design and Analysis of Tunable Piezoelectric Transformer Based DC/DC Converter with AC Output Inductor

Tunable piezoelectric transformer (TPT) is a three-port piezoelectric transformer. Besides the input and output ports, it has a control port. From the electrical point of view, a TPT can be treated as the integration of a resonant tank and an ideal transformer, where the resonant characteristic can be tuned by the control port. Different from TPT based DC/DC converter with DC output inductor, this paper shows a TPT based DC/DC converter with AC output inductor. In this work, the physical meaning of the AC output inductor is explained from two points of view. The benefits of the input inductor, which is commonly utilized in piezoelectric transformer based converters, are also explained. With the help of the AC output inductor, the converter can achieve better efficiency and regulation compared to the one with DC output inductor.