Optical fiber ring network communication system suitable for small current grounding line selection device

The utility model discloses an optical fiber ring network communication system suitable for a small current grounding line selection device. Comprising a voltage acquisition module which is installed at a bus voltage interval and is used for acquiring bus voltage and zero-sequence voltage analog quantity, a current acquisition module which is installed between two adjacent outgoing line intervals and is used for acquiring zero-sequence current, and a main controller which is installed in a main control room and is used for sending opening and closing information according to a sampling value. And the main controller and the voltage acquisition module and the current acquisition module on the circuit are connected in series through optical fibers to form an optical fiber ring network. According to the utility model, the main controller and the acquisition module are distributed, the size is small, the weight is light, the installation position is not limited, optical fiber isolated ring network communication i