A troubleshooting method for a power supply device, wherein the troubleshooting method is applicable to an inverter power supply system in the power supply device, the inverter power supply system comprises at least two direct current to direct current, DC/DC power supply modules , the at least two DC/DC modules are connected in parallel to a same battery and supply power to a load by using a direct current to alternating current, DC/AC power supply, and any one of the at least two DC/DC modules comprises a first fuse (F1) and a second fuse (F2), a first relay (K1) and a second relay (K2), a first inductor (L1) and a second inductor (L2), a first switch module (Q1), a second switch module (Q2), and a third switch module (Q3), and a first direct current bus capacitor (C1) and a second direct current bus capacitor (C2); one terminal of the first relay (K1) is connected to a positive terminal (BAT+) of the battery by using the first fuse (F1), one terminal of the second relay (K2) is connected to a negative terminal (BAT-) of the battery by using the second fuse (F2), the other terminal of the first relay (K1) is connected to connection terminals of the first switch module (Q1) and the second switch module (Q2) by using the first inductor (L1), the other terminal of the second relay (K2) is connected to connection terminals of the second switch module (Q2) and the third switch module (Q3) by using the second inductor (L2), one terminal of the first switch module (Q1) is connected to one terminal of the first direct current bus capacitor (C1), the other terminal of the first switch module (Q1) is connected to one terminal of the second switch module (Q2), the other terminal of the second switch module (Q2) is connected to one terminal of the third switch module (Q3), the other terminal of the first direct current bus capacitor (C1) is connected to the other terminal of the third switch module (Q3) by using the second direct current bus capacitor (C2), and the troubleshooting method comprises: if a faulty component in a faulty module is the first direct current bus capacitor (C1) or the second direct current bus capacitor (C2), and the inverter power supply system is in a battery discharging mode, turning on (S54) the second switch module (Q2) in the faulty module, so that the first fuse (F1) and the second fuse (F2) of the faulty module are blown, to disconnect the faulty module from another DC/DC module, wherein the other terminal of the first direct current bus capacitor (C1) of the faulty module is connected to the other terminal of the first direct current bus capacitor (C1) of the another DC/DC module. if a faulty component in a faulty module is the first direct current bus capacitor (C1) or the second direct current bus capacitor (C2), and the inverter power supply system is in a battery discharging mode, turning on (S54) the second switch module (Q2) in the faulty module, so that the first fuse (F1) and the second fuse (F2) of the faulty module are blown, to disconnect the faulty module from another DC/DC module, wherein the other terminal of the first direct current bus capacitor (C1) of the faulty module is connected to the other terminal of the first direct current bus capacitor (C1) of the another DC/DC module. <EOS>