Method, device and system for realizing power over Ethernet (POE)

The invention discloses a method for realizing power over Ethernet (POE), which comprises the steps of: receiving direct current power supplies provided by power supply equipment (PSE) through at least two ports at a PD side of power receiving equipment; performing load balancing processing on a plurality of the direct current power supplies which enter from the at least two ports; and outputting the direct current power supplies which are subjected to load balancing processing to loads. The embodiment of the invention also provides a POE control device and a POE system. The direct current power supplies are received through multiple ports at a power receiving equipment side; and a plurality of the direct current power supplies are subjected to load balancing processing, so that the functions of load balancing and redundancy backup of the POE are realized, and the stability of system operation is improved.