Current Estimation and Optimal Control in Multiphase DC–DC Converters With Single Current Sensor

The interleaved parallel topology of the dc–dc converter can increase the load capacity and reduce the ripple. However, the multiphase control system requires many current sensors, which increases the software/hardware cost. To solve this problem, this article proposes a dual time-scale model predictive control (DMPC) algorithm based on a single current sensor. First, the current estimator replaces current sensors to measure the unbalanced branch currents and reduce hardware complexity. Then, a DMPC algorithm is proposed to reduce the parallel computational complexity of the controller. Furthermore, a parameter identification module dynamically updates the current estimator and controller to further increase the system’s accuracy. This method reduces the software/hardware complexity while ensuring control effectiveness. The validity of the proposed algorithm is verified on a three-phase buck converter.