POWER SUPPLY SYSTEM

Embodiments of this application provide a power system. Output terminals of a power supply or a DC-to-DC unit are cascaded to increase an output voltage, so as to reduce a current between the power supply or the DC-to-DC unit and the DC-to-AC unit, and resolve cost and loss problems of the cable from the power supply or the DC-to-DC unit to the DC-to-AC unit. In addition, according to the power system provided in the embodiments of this application, a quantity of cables from the power supply or the DC-to-DC unit to the DC-to-AC unit may be further reduced by cascading output terminals of the power supply or the DC-to-DC unit and cascading inputs of the DC-to-AC unit, thereby reducing system costs. In addition, in the power system provided in the embodiments of this application, cascaded input and isolated output of the DC-to-AC unit can reduce a specification of a power conversion device. Therefore, problems of insufficient specifications and high costs of power conversion devices in the current industry are resolved. In addition, according to the power system provided in some embodiments, a problem of potential induced degradation (Potential Induced Degradation, PID) caused by a negative voltage of a battery panel to ground during operation of the system may be further resolved.