Controller Design of Parallel Buck Voltage Balancers for Bipolar DC Microgrids

A control strategy is proposed for parallel and/or interleaved voltage balancers, typically used in bipolar dc power systems. These converters are ideal for dc microgrids where it is desired to increase the dc voltage while minimizing the line to ground potential. A dynamic model for a general number of voltage balancers in parallel is developed and a simplification is used to design the controller. State space output regulation techniques are then utilized to guarantee the stability and desired properties of the closed loop system. Simulation and Control Hardware in the Loop (CHIL) results are presented verifying the feasibility of implementation of the proposed controller.