The full-bridge LC series resonant converter use controlled switches to generate a square wave voltage input for the filter for tank current (iL), formed by the series combination of resonant inductor (Lr) and resonant capacitor (Cr). The resonant inductor current (iL) oscillates and is rectified and filtered to produce dc capacitor output voltage (Vc). The working of the converter is based on the relation between the resonant frequency of the filter and switching frequency and gives nearly sinusoidal current (iL) which is oscillating in nature and has a frequency almost equal to switching frequency when the switching frequency is maintained closer to the resonant frequency of the filter.
Fig. \ref{288400} illustrates the square wave input voltage (Va) to the filter, the current iL, the switch current is1 and the input to the centre tapped rectifier Vb. The square wave voltage (Va) is the inverted waveform of bus voltage (Vbus). The capacitor voltage (Vc) is the rectified form of Vb when iL is positive and -Vc when iL is negative. The output voltage of the converter is assumed to be constant because of the rectifier diode configuration.