Power conversion system and control method therefor

A power conversion system, comprising:

• a first voltage-dividing circuit comprising a first circuit, a third circuit and a first insulation impedance connected in parallel between a positive electrode of the power conversion system and a ground;
• a second voltage-dividing circuit comprising a second circuit, a fourth circuit, and a second insulation impedance connected in parallel between the ground and a negative electrode of the power conversion system, an output terminal of the first circuit being connected to an input terminal of the second circuit, an output terminal of the third circuit being connected to an input terminal of the fourth circuit, and an output terminal of the first insulation impedance being connected to an input terminal of the second insulation impedance;
• a switch module arranged in at least one of the first voltage-dividing circuit and the second voltage-dividing circuit, and a conduction or a disconnection of the at least one of the first circuit and the second circuit being controlled by controlling a conduction or a disconnection of the switch module, and a conduction or a disconnection of at least one of the third circuit and the fourth circuit being controlled by controlling the conduction or the disconnection of the switch module;
• a control module connected to the switch module and configured to control the conduction or the disconnection of the switch module to switch a working mode of the power conversion system to be a detection mode or a normal mode;
• and
• a detection module connected to the first voltage-dividing circuit or the second voltage-dividing circuit, and configured to, in the detection mode, detect a resistance value of the first insulation impedance and a resistance value of the second insulation impedance.