A new current-sharing controller for parallel-connected interleaving CCM PFC converter based on a duty-cycle dynamic

A new current-sharing controller is proposed for parallel-connected PFC converters based on average-current control strategy, it can distribute the control duty-cycle automatically for each parallel-connected PFC converter to implement current balance by the difference from its reference current, and it should be emphasized that the proposed controller also can reduce and even eliminate the disturbance resulted by current-sharing process to total input current and output the voltage with higher input power factor. Moreover, the currents of parallel-connected converters are interleaved to diminish the size of system filter and increase conversion efficiency based on only a single DSP. Taking three parallel-connected PFC converters as an example, the controller addressed above is validated with experimental results in this paper, and it can achieve fine current-sharing performance and reduce the high-frequency ripple in total input current, so it can be a desirable digital solution for parallel-connected PFC converters in large power application.