Current-source parallel-resonant DC/AC inverter with transformer

Abstract

This paper gives the derivation and experimental results for a current-source parallel-resonant inverter with a transformer used to change voltage levels and provide isolation. The analysis is performed in the frequency domain using Fourier series techniques to predict maximum switch voltages, impedances, and transfer functions. The inverter consists of two switches, a large choke inductor, a transformer, and a parallel-resonant circuit (PRC). The magnetizing inductance of the transformer is used as the inductance of the PRC, thereby requiring one less component. Each switch consists of a MOSFET in series with a diode. The MOSFETs have their sources grounded so there is no need for a complicated gate-drive circuit. An inverter was designed and constructed. The input voltage was 156 V and the output voltage was a 224 V peak sine wave at an operating frequency of 50 kHz. The output power at full load was 100 W.<>