Radiator heightens power density of piezoelectric transformers

A new method to heighten the power density of piezoelectric transformers based on heat transfer is presented. The common grounded surface of a piezoelectric plate transformer was closely contacted to an extra smooth copper surface through which the heat can be well dissipated by an aluminium radiator. Although the contact interface may produce additional friction heat, the experimental results show that the mechanism gives excellent performance. The prototype transformer could maintain a power density of 135 W/cm³ with an efficiency of 90.8% for a long working time.