Nippon Telegraph and Telephone Corporation

Naoki Hanaoka

Hidetoshi Takada

Toshimitsu Tanaka

Toshihiro Hayashi

Masaki Kozai

Hiroya Minami

A feeding system that feeds power to a load includes only a single device configured to have neutral point high-resistance between a feeding line and the earth. The device functions as a ground fault overvoltage detection type of ground fault detector. The feeding system further comprises a control device. When the ground fault overvoltage detection type of ground fault detector detects a ground fault, the ground fault overvoltage detection type of ground fault detector transmits, to the control device via a signal line, a signal indicating that the ground fault has occurred. The control device instructs a breaker corresponding to the specific distributed unit in which it is determined that the ground fault has occurred to perform breaking.

Power supply system, ground fault detection method and program

There are included: generation means for generating predetermined information represented by a bit string; and control means for controlling a phase difference between current and voltage of AC power at predetermined time intervals so that each bit value included in the bit string is represented.

Control apparatus, identifying apparatus, control method, identifying method and program

Disclosed is a power management device including a monitoring unit configured to monitor power usage statuses of a plurality of sites individually, a determination unit configured to determine whether to supply the surplus power to a second site of the plurality of sites when the monitoring unit detects that surplus power is generated in a first site of the plurality of sites in accordance with a prediction of a power transmission loss between the first site and the second site, and a site control unit configured to instruct the first site to supply the surplus power to the second site when the determination unit determines that the surplus power is to be supplied to the second site.

Power management apparatus, power management method and program

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.

Power supply system, protection coordination method and program

Provided is a power management apparatus for determining an order of priority with respect to power supply to a consuming device at a target location in a power system that includes a plurality of locations between which power can be interchanged, the target location including at least the consuming device, a power generation unit that generates power from natural energy, a power storage unit, and a commercial power source. The power management apparatus includes a determination unit for determining an order of priority among a plurality of controlled objects including at least power supply from the power generation unit, power supply from the power storage unit, power supply from the commercial power source, and power consumption reduction by transferring a load from the consuming device, and a priority setting unit for setting the order of priority that has been determined by the determination unit for the target location.

Power management apparatus, priority control method and program

Provided is a communication apparatus for making connection to a communication network, including: an optical network unit; and an external power supply input/output terminal, the communication apparatus being configured such that electrical power is fed to the optical network unit from an external terminal that is connected to the external power supply input/output terminal and functions as an auxiliary power supply.

Communication apparatus

Provided is a power management apparatus for controlling power distribution from a location that includes a storage battery and a current control type converter to another location that includes a storage battery, the power management apparatus including: a monitor unit that acquires a status of the storage battery at each location; a judgment unit that determines, based on the status of the storage battery at each location that has been acquired by the monitor unit, a duration of power distribution to a certain location, and one or more locations from which power is to be distributed to the certain location; and a control unit that controls each location serving as a distribution source such that power distribution is performed for the duration determined by the judgment unit.

Growing community of inventors

Musashino, Japan

Naoki Hanaoka