The invention discloses a special power supply for a gate
access control system and a control method thereof. The special power supply includes two independent first input-and-output branches, a second input-and-output
branch, a switching module and a battery management module, wherein each input-and-output
branch possesses an independent protection circuit, meaning that when one of the branches closes the output due to
abnormality, the output of others is not affected, and that when the
abnormality is resolved, the branches can restore to normality automatically. In addition, each input-and-output
branch possesses an independent
abnormality counter; and the times of output closing by a branch due to abnormality becomes greater than a set value, attempts to restore to the
normal state stop automatically, and restoration can only be realized manually. The special power supply disclosed in the present invention supports the power supply to a standby battery. When the
alternating current is
cut off, the two outputs are continuously switched and supplied with power by the standby battery. When the
alternating current is restored, the
system can automatically switch to the
alternating current output and charges the batteries.