Simplified digital average current mode control algorithm for half- or full-bridge isolated DC/DC converters

This paper proposes a new digital average current mode control method (AVCMC). Instead of sampling and summing the transformer primary current over the switching period, the average is calculated merely using two current values. Analysis of the primary current shape allows a simplified equation to be derived for the digital AVCMC. The method is adoptable in cases where current is growing linearly. In order to estimate maximal possible errors introduced by nonlinearity of the current slope, the paper analyzes and simulates different current shapes. Simulation results are verified on a real test prototype.