Control method for power supply system and power supply system

A power supply system, comprising:

• a three-phase voltage source, configured to generate voltage sources corresponding to three phases;
• a power supply module, comprising a plurality of power transforming modules respectively coupled to the three-phase voltage source, to respectively generate a plurality of direct current voltages according to the three phases of the three-phase voltage source;
• a backup supply module, coupled to the power supply module, wherein the backup supply module comprises at least one backup transforming module corresponding to the three phases of the three-phase voltage source, and each backup transforming module comprises the plurality of switch elements respectively coupled to the three phases of the three-phase voltage source, such that when at least one of the plurality of power transforming modules is in an abnormal operation, the backup transforming module corresponding to the power transforming module in the abnormal operation generates the plurality of direct current voltages according to the three-phase voltage source;
• a logic control circuit, coupled to the power supply module and the backup supply module, configured to determine whether the plurality of power transforming modules and the at least one backup transforming module operate normally or not according to a plurality of working signals corresponding to each of the plurality of power transforming modules and each backup transforming module;
• and
• a driving circuit, coupled to the at least one backup transforming module and the logic control circuit, and configured to generate a switch signal according to the working signal corresponding to the power transforming module in the abnormal operation so as to conduct a switch element of a first backup transforming module of the backup supply module corresponding to the phase of one of the plurality of power transforming modules in the abnormal operation;
• an enabling circuit, configured to generate an enabling signal to the first backup transforming module according to the switch signal.