Multi-phase switching method for paralleling power systems

A multi-phase switching scheme for paralleling power systems is presented. It can operate without current sharing compensator and it is not necessary to adjust the reference voltage in the feedback loop of each power supply. Furthermore, different rated output power units can be paralleled and composed of a large power system by this scheme. A Precision Time synchronization Protocol (PTP) is introduced. Because a digital control method for current-sharing in our scheme needs precise clocks and PTP can synchronize time in the sub-microsecond (10^-6 s) range.