# US 12,113,350 B2 · Power supply system, protection coordination method and program > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,113,350 B2 - Document ID: US12113350B2 - Status: Granted - Kind: B2 - Application number: 17/920,098 - Filed: 2020-05-18 - Published: 2023-06-08 - Granted: 2024-10-08 - Earliest claimed: 2020-05-18 - Assignees: Nippon Telegraph and Telephone Corporation - Applicants: Nippon Telegraph and Telephone Corporation - Inventors: Naoki Hanaoka; Hidetoshi Takada; Masaki Kozai - Web page: https://patentgrep.com/patent/US12113350B2 ## CPC - H02H 3/087: for DC applications - H02H 3/05: with means for increasing reliability, e.g. redundancy arrangements {(for logic circuits H03K19/003)} - H02H 3/16: responsive to fault current to earth, frame or mass (with balanced or differential arrangement H02H3/26 {; monitoring earth connection H02H5/105}) - H02H 3/33: using summation current transformers (H02H3/347 takes precedence) - H02H 7/268: {for DC systems} - H02J 1/00: Circuit arrangements for DC mains or DC distribution networks - H02H: EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS (indicating or signalling undesired working conditions G01R, e.g. G01R31/00, G08B; locating faults along lines G01R31/08; emergency protective devices H01H) - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY ## Abstract A feeding system feeds power from a power unit to a load via a feeding line and includes a protection device configured to operate by a current equal to or greater than a predetermined current; a monitoring unit configured to monitor whether an accident occurs in the feeding line; and a gate block unit configured to stop the feeding of the power of the power unit when the monitoring unit detects that an accident causing the protection device not to operate has occurred. ## Claims ### Claim 1 A feeding system configured to feed power from a power unit to a load via a feeding line, the feeding system comprising: a protection device configured to operate with a current equal to or greater than a predetermined current; a monitoring unit configured to monitor whether an accident occurs in the feeding line; a gate block unit configured to stop feeding of the power of the power unit when the monitoring unit detects that an accident causing the protection device not to operate has occurred; and a control unit configured to operate the protection device after the gate block unit operates. ### Claim 2 (depends on 1) The feeding system according to claim 1, wherein, when the monitoring unit detects that a current less than the predetermined current flows in the feeding line for a predetermined time or more or detects that a feeding voltage decreases for a predetermined time or more, the monitoring unit is configured to determine that a short circuit or a ground fault has occurred as the accident in the feeding line. ### Claim 3 (depends on 1) The feeding system according to claim 1, further comprising: a plurality of distributed units distributed from a distribution board connected to the power unit, wherein each distributed unit includes a protection device, and wherein, after the gate block unit operates, the control unit is configured to operate the protection device of the distributed unit closest to an accident point or transmits a signal, or operates the protection device and transmits the signal. ### Claim 4 (depends on 3) The feeding system according to claim 3, wherein each distributed unit includes an unbalanced current detection type of ground fault detector, and wherein the control unit determines whether a ground fault has occurred in a specific distributed unit based on a ground fault detection result obtained through ground fault overvoltage detection in the monitoring unit and a ground fault detection result obtained in each distributed unit by the unbalanced current detection type of ground fault detector. ### Claim 5 (depends on 3) A non-transitory computer readable medium storing a program, wherein executing of the program causes a computer to operate as the control unit in the feeding system according to claim 3. ### Claim 6 (depends on 1) The feeding system according to claim 1, further comprising: a plurality of distributed units distributed from a distribution board connected to the power unit, wherein each distributed unit includes a protection device, and wherein, after the gate block unit operates, the control unit is configured to add a voltage to the feeding line, operate the protection devices of the distributed units in order one by one, and determine that the accident has occurred in the distributed unit that immediately previously operated one of the protection devices when detecting that a current no longer flows before operating the one of the protection devices. ### Claim 7 (depends on 6) The feeding system according to claim 6, wherein each distributed unit includes an unbalanced current detection type of ground fault detector, and wherein the control unit determines whether a ground fault has occurred in a specific distributed unit based on a ground fault detection result obtained through ground fault overvoltage detection in the monitoring unit and a ground fault detection result obtained in each distributed unit by the unbalanced current detection type of ground fault detector. ### Claim 8 (depends on 6) A non-transitory computer readable medium storing a program, wherein executing of the program causes a computer to operate as the control unit in the feeding system according to claim 6. ### Claim 9 (depends on 1) The feeding system according to claim 1, further comprising: a plurality of distributed units distributed from a distribution board connected to the power unit, wherein each distributed unit includes an unbalanced current detection type of ground fault detector, and wherein the control unit is configured to determine whether a ground fault has occurred in a specific distributed unit based on a ground fault detection result obtained through ground fault overvoltage detection in the monitoring unit and a ground fault detection result obtained in each distributed unit by the unbalanced current detection type of ground fault detector. ### Claim 10 (depends on 9) A non-transitory computer readable medium storing a program, wherein executing of the program causes a computer to operate as the control unit in the feeding system according to claim 9. ### Claim 11 (depends on 1) A non-transitory computer readable medium storing a program wherein executing of the program causes a computer to operate as the control unit in the feeding system according to claim 1. ### Claim 12 A protection coordination method performed by a feeding system configured to feed power from a power unit to a load via a feeding line, comprising: operating, by a protection device, with a current equal to or greater than a predetermined current; monitoring, by a monitoring unit, whether an accident occurs in the feeding line; performing gate block to stop feeding power of the power unit when detecting that the accident causing the protection device not to operate has occurred; and operating the protection device after performing the gate block.