DISTRIBUTION GRID FAILURE SYMPTOM CAUSE ESTIMATION SYSTEM

Protection distribution devices including switches, disposed on a distribution grid, are individually provided with slave stations. The slave stations are connected to each other via communication lines and connected to a high-order server. Each slave station includes a failure symptom cause estimation circuitry to estimate a symptom cause for failure on the distribution grid on the basis of waveform data measured by a measurement circuitry which performs signal processing on waveform data of current or voltage detected by the protection distribution device, and a data transmitter/receiver to transmit an estimation result for the symptom cause for failure on the distribution grid obtained by the failure symptom cause estimation circuitry, to the server. The failure symptom cause is autonomously estimated through mutual communication among the slave stations.