A power supply
system (1001) according to the present disclosure supplies power to a
relay apparatus (2) on a branching
submarine cable branched from a
trunk submarine cable by a branching apparatus (1). The power supply
system (1001) according to the present disclosure supplies power to the
relay apparatus (2) by a branching power supply path (BE) connected to a
trunk power supply path (TE) provided in a
trunk submarine cable. When power is supplied to the
relay apparatus (2), the branching power supply path (BE) causes a current flowing from one side of the trunk
submarine cable to flow to the relay apparatus (2), and then causes the current to turns back so that the current flows to the other side of the trunk
submarine cable.