A nonlinear control scheme for independent stabilization of a parallel multi-phase boost converter by blocking pure zero-sequence current

We propose a 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 N modules. Each of the closed-loop power-converter modules operates asynchronously without any communication with the other module. The controller stabilizes the currents on the dq axes by blocking the flow of the pure-zero sequence current. The dynamic performance of the converter using the proposed nonlinear controller is much superior compared to that obtained using a linear controller. The steady-state performances of the two controllers are comparable.