The invention relates to a
parallel communication power supply
system and a control method thereof. A positive
busbar and a negative
busbar of a main power supply are connected with a positive
busbar and a negative busbar of a slave power supply respectively; the rated output
voltage of the slave power supply is higher than that of the main power supply; and the slave power supply is also provided with a
current limiting point, and an output current of the slave power supply does not exceed the current corresponding to the
current limiting point. When the external load is the
light load or the
normal load, the
current limiting point is a normal current limiting point and the normal current limiting point remains the same; when the external load is the
heavy load, the current limiting point changes with the load. The two sets of the power supplies which are connected in parallel can realize the
capacitance expansion without communication, the
voltage deviation exists between the main power supply and the slave power supply, and the current limiting point is arranged on the slave power supply to realize the current automatic distribution among power supply modules which are connected in parallel, so that the load is appropriately distributed among the power supply modules; moreover, the regulation and the setting of parameters are simple, and the
cut-over process is so simple that the positive and the negative busbars of the two sets of the power supplies are only required to be connected respectively. The
system can be used for
capacitance expansion of the prior one set of the power supply and can also realize the 1 plus 1 hot
backup of partial
capacitance.