Fuji Electric Co., Ltd.

Hokuriku Electric Power Company

Motohiro Katayama

Toshiya Yamada

Kansuke Fujii

Kazuyoshi Umezawa

Masaki Katoh

Norikazu Kanao

The disclosed distributed power supply system does not become disconnected from a grid simultaneously with others when the grid voltage falls instantaneously. In a distributed power supply device which controls an inverter circuitbased on a control signal obtained by comparing a predetermined carrier signal and voltage command signals of three phases and which converts DC power to AC power and supplies the AC power to a power grid of a three-phase AC power supply, fundamental wave signals of three phases are generated from a grid voltage of the three-phase AC power supply. A reference cosine wave signal is generated from the fundamental wave signals of three phases. A third harmonic signal is generated from the reference cosine wave signal and the fundamental wave signals of three phases. The three-phase fundamental wave signals and the third harmonic signal are added to generate voltage command signals of three phases.

Distributed power supply system

A distributed power supply system in which no simultaneous disconnection from the system occurs when a system voltage momentarily drops is provided. It includes an inverter circuit that converts a direct current power generated by a direct current power supply and that supplies the alternating current power to an alternating current power supply power system, and an inverter control circuit for carrying out PWM control of the inverter circuit, wherein the inverter control circuit includes a three-phase voltage command signal generation unit, that is configured of a three-phase fundamental wave signal generation unit that generates three-phase fundamental wave signals from two phase components of voltage detected by a voltage detector, and a third harmonic signal generation unit that adds together third harmonic components of respective phases, having a predetermined amplitude, generated based on the three-phase fundamental wave signals.

Distributed power supply system with harmonic signal generation for stabilization

Growing community of inventors

Kanagawa, Japan

Motohiro Katayama