基于数字死区平均电流控制与负载电流前馈的主动纹波抑制技术

The insulated gate bipolar transistor (IGBT) and gallium nitride (GaN) hybrid half-bridge (HHB) circuit operating in fractional power processing (FPP) mode combines the advantages of silicon devices and wide bandgap devices to achieve the optimal tradeoff among efficiency, power quality, and cost. However, due to the fact that the load transient response of HHB circuit depends on the IGBT branch with lower switching frequency, the system load transient response is poor. To overcome this issue, an active ripple suppression technique based on digital dead-beat average current (DBAC) control and load current feed-forward for both IGBT branch and GaN branch in the HHB circuit is proposed in this letter. The operating principle and control law of proposed control for the HHB circuit in FPP mode are analyzed in detail. The load transient performance of the HHB circuit is further investigated. Finally, experimental results of the active ripple suppression technique for the IGBT and GaN HHB circuit are provided to verify the correctness of the theoretical analysis.