Research and simulation of parallel current-mode controlled buck converter

This paper introduces parallel current-mode control algorithm for DC-DC converters. The remarkable advantage of this new control is that it is derived directly in a discrete form and optimized for digital implementation. The duty cycle consists of two terms: voltage term and current term. They are calculated directly by the reference current, sensed inductor current, input voltage and output voltage, and only need three additions and two multiplications. Due to this, the algorithm is simple for digital implementation. At the same time, the proposed control method can also obtain good dynamic performance under load and input voltage variations. The assumptions are verified by simulations on synchronous buck converter for this new strategy using PSIM. Meanwhile, conventional peak current-mode control is presented and simulated as comparison. The proposed method can be applied to other topology such as boost, Buck-Boost, etc.