The invention discloses a
soft switching three-phase gird-connected
inverter additionally provided with a freewheeling path, which comprises an
inverter direct current power supply, a three-phase bridge arm formed by six full-control master switches with antiparallel diodes, and output filter inductors respectively connected between the midpoint of each phase of the bridge arm and an
alternating current grid, wherein the three-phase bridge arm is connected with a full-
control switch with an antiparallel
diode, the full-
control switch and the six master switches of the three-phase bridge arm are respectively connected with a
capacitor in parallel, an auxiliary switch with an antiparallel
diode and a serial
branch of a
clamp capacitor are accessed between the
inverter direct current power supply and a
direct current bus of the three-phase bridge arm, and a
resonance inductor Lr is bridged at two ends of the serial
branch, and the auxiliary switch is connected in parallel with the
capacitor. The invention is simple in structure, can suppress the
reverse recovery of the diodes, and reduces the
electromagnetic interference. All switches of the inverter realize zero-
voltage switching-on, thus the inverter has the advantages of little switching loss and high circuit efficiency. The inverter can realize control of power factors and
harmonic waves for output grid-connected current, and can be used in a grid-connected inverter in various power supplies.