Sanyo Electric Co., Ltd.

Sanyo Electronics Co., Ltd.

Takeo Ishida

Ryuzo Hagihara

Kenji Uchihashi

Hitoshi Kishi

Hirosato Yagi

Osamu Tajima

Masahiro Makino

Kazuo Ito

Wataru Horio

Yasuhiro Yagi

Ryuzo Hagiwara

Haruhiko Tatsumi

Shinichi Kozuma

A grid interconnection device includes a relay controller configured to control separation or interconnection of a relay; a receiver configured to receive, from a predetermined transmission path, power failure information containing at least local area information indicating an area in which a power failure occurs; a determination unit configured to determine an occurrence of a power failure in a power distribution system, when the power failure information includes local area information of an area to which the power distribution system belongs; and a detector configured to detect an islanding state. The detector increases detection sensitivity of the islanding state when the determination unit determines the power failure in the power distribution system. The relay controller performs separation control for the relay when the islanding state is detected by the detector.

Grid interconnection device, grid interconnection system and transfer trip system

This invention provides a method for suitably using a method for collectively receiving at a high voltage and distributing at a low voltage in collective housing. In this method for collectively receiving at a high voltage and distributing at a low voltage to a plurality of users, a distribution control part for collectively receiving power and distributing the power at a low voltage includes a serverand a control devicefor controlling information on power consumed by the users. The control deviceand the server are connected via a network. The servergrasps a maximum current capacity necessary for each user, determines a contracted current depending on the grasped maximum current capacity, and distributes power to each user.

Method for collectively receiving at high voltage and distributing at low voltage, and collective housing using same

A system for reducing power without making users feel inconvenience and discomfort in collective housing or the like. The system includes a plurality of air conditioners and a central control unit connected with the air conditioners via a communication line. The central control unit controls the plurality of air conditioners to operate in time or alternately to prevent electric current concentration.

Power load control system

A controller of a data communication apparatus according to the present invention stores information on each successful and unsuccessful data communication, a season, a data of the week, a time, and a data communication rate of the communication for each site in a data memory. The controller reads out a data communication rate at which a data communication succeeded from the data memory and directs a modem to conduct a communication at the data communication rate. A data communication is conducted at the directed data communication rate. These procedures ensure a secure link between sites and a secure data communication irrespective of a line distance between the sites etc.

Data communication apparatus

The present invention prevents an increase in an overvoltage and increases an optimum operating voltage of a power inverter. A photovoltaic power generation device is provided with a solar cell device,, a power inverter,for inverting output from the solar cell device,into AC power, a current path circuit,connected in parallel between the solar cell device,and the power inverter,, and a current detection circuit,for detecting a current feeding back to the solar cell device,. When a current detected by the current detection circuit,reaches beyond a predetermined current value, the current path circuit,is cut off.

Photovoltaic power generation device

A device for operating inverters according to the present invention can operate a plurality of inverters for converting DC output from a DC source such as a solar cell to AC output efficiently without relying on a particular inverter. The plurality of inverters are connected to the DC source through switches. DC output from a DC source is measured by a measuring device to determine the number of inverters to be operated on a basis of the output result from the measuring device. The inverters to be added or cut off are determined among the plurality of inverters at random on a basis of the random number and switches of the determined inverters are turned ON or OFF in order to select inverters to be operated.

Device for operating inverter and power system

The present invention is directed to a photo-voltaic apparatus comprising a photo-voltaic module having a plurality of photo-voltaic cells, and an inverter for converting a direct current output generated from the photo-voltaic cells into an alternating current and outputting the alternating current, the inverter being mounted on a surface opposite to the light receiving surface of the photo-voltaic module with a clearance provided therebetween, so that heat self-generated by the inverter can be efficiently radiated, and heat from the photo-voltaic module is not transferred to the inverter.

Photo-voltaic apparatus

A power-supply system involving system interconnection includes a plurality of AC modules, each of which includes a solar cell module and an inverter unit which outputs a single-phase alternating current. The AC modules are connected to the single-phase three-wire distribution line such that the number of AC modules connected to the outer conductor R is the same as the number of AC modules connected to the outer conductor T. Each AC module has three junction pole pieces. Adjacent AC modules are connected to each other via a connecting cable connected to the junction pole pieces. Each AC module has a change-over circuit so as to be selectively connected to one of the outer conductors R or T. The power-supply system further includes an independent operation control device for independently operating the AC modules when the connection between the AC modules and the commercial electric power system is cut.

Growing community of inventors

Hirakata, Japan

Takeo Ishida