Closed loop controlled solar fed post regulated push-pull converter

A solar fed push-pull converter employing post regulation method with soft commutated switches is discussed in the paper. Incorporating an inductor in series with the source the converter operates as a current fed one. The post regulation is carried out with an auxiliary current transformer. The post regulation technique utilizes the Transformer Turns Ratio Regulator concept which adds or subtracts voltage to the output of the push-pull converter. A boost converter is incorporated at the secondary side of the transformer and a current is fed to the input of the converter. The amount of current fed is controlled by the regulator circuit which handles only a percentage of the total output power. The power handling capacity of the load is enhanced with an improvement in efficiency and regulation. The size and weight of the converter is reduced by suitably selecting higher switching frequencies. In order to reduce the switching losses, zero voltage and zero current switching (ZVZCS) have been employed. The remarkable feature of the paper presented is that the soft switching is not affected by load variations. This is discussed in detail with resonant waveforms, output waveforms and efficiency curves.