A power conversion system configured to convert a DC input voltage (Vdc) into an AC output voltage (Vac); the power conversion system comprising: an input capacitor bank having a first capacitor and a second capacitor, and the first capacitor and the second capacitor connected to a neutral point (Po) and configured to receive the DC input voltage (Vdc); a first conversion circuit connected in parallel to the input capacitor bank; a second conversion circuit connected in parallel to the input capacitor bank; a first filtering circuit connected between the first conversion circuit and the second conversion circuit, and an output side of the first filtering circuit connected to the neutral point (Po); a second filtering circuit connected between the first conversion circuit and the second conversion circuit, and an output side of the second filtering circuit connected to the neutral point (Po); and a control circuit configured to produce a plurality of control signals (Sc1, Sc2) to correspondingly control the first conversion circuit and the second conversion circuit, thus reducing leakage current (Icp1, Icp2) of the DC input voltage (Vdc) caused by parasitic capacitance voltage; characterized in that the first conversion circuit comprises a first branch, a second branch, and a first auxiliary branch; the first branch is composed of a first power switch and a first diode connected to the first power switch; the second branch is composed of a second power switch and a second diode connected to the second power switch; the first auxiliary branch is composed of a first auxiliary power switch and a first auxiliary diode connected to the first auxiliary power switch; the first auxiliary branch is connected between the first branch and the second branch; the control circuit is configured to produce a first control signal to control the first power switch and the second power switch, and produce a first auxiliary control signal to control the first auxiliary power switch; and that the second conversion circuit comprises a third branch, a fourth branch, and a second auxiliary branch; the third branch is composed of a third power switch and a third diode connected to the third power switch; the fourth branch is composed of a fourth power switch and a fourth diode connected to the fourth power switch; the second auxiliary branch is composed of a second auxiliary power switch and a second auxiliary diode connected to the second auxiliary power switch; the second auxiliary branch is connected between the third branch and the fourth branch; the control circuit is configured to produce a second control signal to control the third power switch and the fourth power switch, and produce a second auxiliary control signal to control the second auxiliary power switch. an input capacitor bank having a first capacitor and a second capacitor, and the first capacitor and the second capacitor connected to a neutral point (Po) and configured to receive the DC input voltage (Vdc); a first conversion circuit connected in parallel to the input capacitor bank; a second conversion circuit connected in parallel to the input capacitor bank; a first filtering circuit connected between the first conversion circuit and the second conversion circuit, and an output side of the first filtering circuit connected to the neutral point (Po); a second filtering circuit connected between the first conversion circuit and the second conversion circuit, and an output side of the second filtering circuit connected to the neutral point (Po); and a control circuit configured to produce a plurality of control signals (Sc1, Sc2) to correspondingly control the first conversion circuit and the second conversion circuit, thus reducing leakage current (Icp1, Icp2) of the DC input voltage (Vdc) caused by parasitic capacitance voltage; characterized in that the first conversion circuit comprises a first branch, a second branch, and a first auxiliary branch; the first branch is composed of a first power switch and a first diode connected to the first power switch; the second branch is composed of a second power switch and a second diode connected to the second power switch; the first auxiliary branch is composed of a first auxiliary power switch and a first auxiliary diode connected to the first auxiliary power switch; the first auxiliary branch is connected between the first branch and the second branch; the control circuit is configured to produce a first control signal to control the first power switch and the second power switch, and produce a first auxiliary control signal to control the first auxiliary power switch; and that the second conversion circuit comprises a third branch, a fourth branch, and a second auxiliary branch; the third branch is composed of a third power switch and a third diode connected to the third power switch; the fourth branch is composed of a fourth power switch and a fourth diode connected to the fourth power switch; the second auxiliary branch is composed of a second auxiliary power switch and a second auxiliary diode connected to the second auxiliary power switch; the second auxiliary branch is connected between the third branch and the fourth branch; the control circuit is configured to produce a second control signal to control the third power switch and the fourth power switch, and produce a second auxiliary control signal to control the second auxiliary power switch.