Interleaved hybrid control concept for multiphase DC-DC converters

DC-DC converters with high dynamic performance and low current ripple, able to drive highly fluctuating loads are nowadays required in a range of applications (e.g. accelerators, plasma research, fusion reactors). In order to fulfill the requirements of these applications, advanced current control concepts have to be employed to harness the full potential of the designed topology. In this paper, an interleaved hybrid current control concept is introduced for multiphase DC-DC converters. The controller combines the time optimal transient behavior of the hysteretic control with the constant switching frequency of the PI control along with a phase-shifting controller. This combination results in a highly dynamic performance during transients, excellent disturbance rejection capability during load disturbances, and minimum ripple during steady state without increasing excessively the complexity of the controller. The interactions between the hysteretic controller, the PI controller and the phase-shifting controller are described and the ability of the control scheme to fully utilize the converter's capabilities is validated through detailed simulations.