A Novel Discrete Control Strategy for Independent Stabilization of Parallel Three-Phase Boost Converters by Combining Space-Vector Modulation With Variable-Structure Control

We propose a discrete nonlinear controller, developed in a synchronous frame, for a parallel three-phase boost converter consisting of two modules. The basic idea, however, can be extended to a system with modules. Each of the closed-loop power-converter modules operates asynchronously without any communication with the other modules. The controller stabilizes the currents on the -axes and limits the flow of the pure-zero sequence current. It combines the space-vector modulation scheme with a variable-structure control, thereby keeping the switching frequency constant and achieving satisfactory dynamic performance.