Technical Lecture Session
Control of DC-DC Converters
Vertical Crossings, Muti-Sampling, Digital Control
Multi-sampling method, to update the modulating signal N times in each switching period, is an effective approach to reduce delay in digital controlled power converters. However, this method may deteriorate the performance of converters due to vertical crossings of modulating signal and carrier signal, when the closed-loop regulation will be lost. And this phenomenon is influenced by the operating point, parameters of power stage and control system. Therefore, it is significant to predict the vertical crossings with parameters of power converters. This paper proposes an accurate condition of vertical crossings for multi-sampled digital-controlled buck converters, where the output capacitance and sampling delay is taken account, and it will be useful for accurately predict the vertical crossing. Finally, the theoretical analysis is validated by the simulation and experiment results.