Interleaving Quasi-Sliding-Mode Control of Parallel-Connected Buck-Based Inverters

An interleaving fixed-switching-frequency quasi-sliding control algorithm based on the zero average dynamics approach is reported and applied to the design of a modular system of parallel-connected single-phase inverters. This approach is used in a laboratory prototype of three inverters with field-programmable gate array control-based implementation embedding this algorithm, as well as a power management strategy for handling the number of active inverters. Experimental results are provided to illustrate the design features in terms of AC output voltage regulation, balanced current sharing among mismatched modules, interleaved fixed-switching-frequency operation and robustness with respect to load variations, and inverter activation during system operation.