Ebara Densan Ltd.

Ebara Corporation

Seiichi Ishihara

Tadashi Kataoka

Takahide Ozawa

Noboru Kinoshita

Tai Furuya

Eishi Marui

Terence McKelvey

Motoyasu Sato

Shaojun Zheng

Masahiro Miyamoto

Motoyasu Satoh

Shao-jun Zheng

Terence Mckelvey

A power supply system for supplying power to a load is provided. The system comprises power-line carriers for supplying power to the load, and a plurality of power supply units the outputs of which are parallelly connected to power-line carriers. Each of the power supply unit comprises a generator; an inverter for converting a voltage generated by the generator into an AC voltage and outputting the AC voltage; an inverter control unit for controlling the inverter, and a connection apparatus for connecting the AC voltage outputted from the inverter to the power-line carriers. The inverter controller comprises a load sharing adjuster for adjusting a shared load current supplied from the power supply unit, so that at least one of the power supply units in operation can operated at its rating condition, thereby realizing an efficiency operation.

Electric power supply system

To provide an interconnecting power generation system which can detect an abnormality in the utility power supply and can be isolated from a utility power system and can prevent damage to a turbogenerator. An interconnecting power generation system comprises: an interconnecting inverter; a voltage phase shift circuitwhich synchronizes the output voltage phase of the interconnecting inverterwith the utility power voltage phase and monitors zero crossings of the utility power voltage, and which shifts the output voltage phase from the utility power voltage phase and shifts the shifted output voltage phase to the utility power voltage phase; a phase comparatorfor comparing the voltage phase of the utility power systemand the output voltage phase of the interconnecting inverter; and an interconnection control unitwhich detects a power outage caused by an interruption of power supply from the utility power systembased on a series of a predetermined number of matching signals outputted from the phase comparatorand sends a control signal to a circuit breakerto shut off the output of the interconnecting inverterfrom the utility power system

Interconnecting power generation system

A gas turbine generating apparatus according to the present invention comprises a gas turbine capable of a high-speed operation, a permanent-magnet-type generator driven at a high speed by the gas turbine, an inverter device () for converting alternating-current power generated by the generator into commercial alternating-current power, and a system-interconnection device () for interconnecting output of the inverter device to a commercial AC power supply system (). The system-interconnection device controls the inverter device based on voltage of the commercial AC power supply system as a criterion such that output current of the inverter device is in phase with the voltage or out of phase with the voltage by a constant phase difference. A control device () is provided for operating the permanent-magnet-type generator () as a motor at a time of starting the gas turbine, and supplying alternating-current power from a direct-current power supply through the inverter device or another inverter device in addition to the inverter device to the generator for increasing a rotational speed smoothly from zero. The control device detects output current of the inverter device and controls the inverter device to keep the output current constant.

Gas turbine generating apparatus

A power generating apparatus has a power generatorfor generating AC power, a gas turbine enginefor driving the power generator, and an inverter devicefor converting the AC power into commercial AC power. The power generating apparatus includes an interconnection switch Sfor connecting an output of the inverter devicewith a commercial AC power supply system, a first voltage detectorfor detecting a DC power supply voltage Vdc-in of the inverter device, and a second voltage detectorfor detecting a full-wave rectification voltage of the commercial AC power supply system. The power generating apparatus also includes an interconnection control partfor closing the interconnection switch Swhen the DC power supply voltage of the inverter deviceexceeds the full-wave rectification voltage of the commercial AC power supply system.

Power generating apparatus

Gas turbine generator

Growing community of inventors

Fujisawa, Japan

Seiichi Ishihara