Piezoelectric Transformer Based Current-Source Charge-Pump Power-Factor-Correction Electronic Ballast

This paper presents the piezoelectric transformer (PT)-based continuous-conduction-mode (CCM) current source (CS) charge-pump (CP) power-factor-correction (PFC) electronic ballast. The main drawbacks of the PT-based dc-side discontinuous-conduction-mode (DCM) CS CP-PFC electronic ballast include high di/dt, high current stress and high switching losses. In order to solve these problems that are caused by DCM operation, and to reduce the components count, the PT-based bridgeless CCM CS CP-PFC electronic ballast is proposed in this paper. The experimental results show that the electronic ballast proposed in this paper not only can achieve high power factor and low total harmonic distortion, but also the switches can operate under a zero-voltage-switching condition without requiring a series inductor in front of the employed PT.