Sumitomo Electric Industries, Limited

Fumio Urakawa

Tetsuo Akita

Koichi Takeshita

Naoki Ayai

Toshiaki Okumura

Shinjirou Shinada

Tadatsugu Udono

A storage battery system includes: a grid-connected storage battery; and a first current sensor that is provided in an electrical circuit linking the storage battery and the grid and detects a current in the electrical circuit the storage battery system having the electrical circuit connected with one or more power generators. The storage battery system includes: a second current sensor that is provided in the electrical circuit such that the one or more power generators are connected between the first current sensor and the second current sensor; and a controller that calculates generated power of the one or more power generators based on outputs obtained from the first current sensor and the second current sensor.

Storage battery system and power display device

This abnormality detection method for a single-phase AC input voltage is executed by a control unit having a function of a phase locked loop, and includes: sequentially generating a simulated voltage waveform with a phase synchronized with the input voltage, by using the phase locked loop; and within a period until a next update of the generated simulated voltage waveform, comparing the instantaneous value of the input voltage with the simulated voltage waveform, and when the instantaneous value of the input voltage changes from a state of being along the simulated voltage waveform to a state of not being along the simulated voltage waveform, determining that the input voltage is abnormal.

Input-voltage-abnormality detection method and power source device

A power conversion device provided between a DC power supply and an AC electric path, including: a breaking device provided to at least one line of an output electric path in the power conversion device; a first voltage sensor provided on a primary side of the breaking device; a second voltage sensor provided on a secondary side of the breaking device; and a determination unit which calculates a primary-side voltage and a secondary-side voltage, and a primary-side phase and a secondary-side phase and determines that the breaking device is opened, by occurrence of an event in which an absolute value of a voltage difference between the primary-side voltage and the secondary-side voltage is greater than a voltage difference threshold value and an absolute value of a phase difference between the primary-side phase and the secondary-side phase is greater than a phase difference threshold value.

Growing community of inventors

Osaka, Japan

Fumio Urakawa