Design of a Power Transformer for a LLC Resonant Power Converter

Abstract

We designed and implemented a power converter to provide a dc power bus for the MCOR 12 correction supply. The characteristics of the dc power bus are variable frequency at both heavy and medium or light loads. These characteristics match the working requirement of the correction supply. The dc power bus has a relaxation oscillator that generates a symmetric triangular waveform, to which MOSFET switching is locked. The frequency of this waveform is related to a voltage to be modulated with feedback circuitry. As a result, the circuit and complex transformer are driven with a half-bridge. We designed the complex resonant transformer and describe in this paper a simulation model that is highly important, thus to exploit its frequency-dependent transfer characteristics. We obtained a power bus with small ripple to provide the correction power. The high-performance characteristics of the resonant dc power bus are illustrated in this paper.