Abstract：In order to further improve the output performance and efficiency of the converter，a grid-connected

converter based on heterogeneous device mixing was proposed，referred to as heterogeneous grid-connected

converter（HGCC）. The HGCC consists of two half-bridge modules based on SiC MOSFET devices，which are

cross-connected by the commutation bridge arm based on Si IGBT devices. Furthermore，the HGCC modulation

principle was given. The SiC MOSFET device works in the high-frequency switching state，while the Si IGBT

device works in the low-frequency switching state，giving full play to the advantages of low switching loss of SiC

devices and low on-state loss of Si devices. Then，the working mode of HGCC was analyzed in detail，and the

control block diagram of HGCC and the internal voltage balancing strategy of capacitor were given. Finally，the

effectiveness and feasibility of the proposed topology and control strategy was verified by simulation.

      Key words：grid-connected converter；Si IGBT device；SiC MOSFET device；modulation strategy；voltage

stabilization strategy