Ebara Corporation

Ebara Densan Ltd.

Eishi Marui

Tadashi Kataoka

Tai Furuya

Terence McKelvey

Masahiro Miyamoto

Takahide Ozawa

Noboru Kinoshita

Seiichi Ishihara

Motoyasu Sato

Shaojun Zheng

Mamoru Suzuki

Yuji Shirao

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 apparatus is provided which comprises a turbine, a combustor for burning a mixture of air and fuel and providing the turbine with a combustion gas to drive it, a generator connected to the turbine to receive rotational force therefrom to generate electric power, a temperature sensor for measuring a temperature of an exhaust gas from the turbine, a temperature setting unit and a power setting unit. The power setting unit sets a set output power of the generator such that a first set output power is set when starting-up the generator, the first set output power is decreased at a first rate when the measured exhaust gas temperature reaches a second set temperature higher than a first target temperature, a currently set output power is decreased at a second rate higher than the first rate when the measured exhaust gas temperature reaches a third set temperature higher than the second set temperature after decreasing the set output power at the first rate, and a currently set output power is increased at a third rate smaller than the second rate when the exhaust gas temperature reaches a forth set temperature smaller than the first set temperature after decreasing the set output power at the second rate.

Gas turbine apparatus

A gas turbine apparatus has a combustorfor combusting fuel to produce a combustion gas, a turbinewhich is rotated by the combustion gas, an electric generatorcoupled to the turbine, and a fuel flow control valveconfigured to change an opening thereof The gas turbine apparatus includes a first PID processing unitto adjust the opening of the fuel flow control valveso as to maintain a rotational speed of the turbinesubstantially at a constant value, and a second PID processing unitto adjust the opening of the fuel flow control valveso as to maintain a temperature of a discharged combustion gas at temperatures lower than a predetermined temperature. The gas turbine apparatus has an electric power controllerto control electric power to be generated by the electric generatorbased on output values of the first PID processing unitand the second PID processing unit

A gas turbine starting method, comprising the steps of rotatively driving a turbine by a motor coupled to the turbine, while at the same time supplying a compressed air to a combustor by an air compressor operating in interlocking motion with the turbine, starting a fuel supply to the combustor when a revolution speed of the turbine has reached up to a predetermined value, and simultaneously starting an igniting operation on an air-fuel mixture in the combustor, wherein at least during the igniting operation to the air-fuel mixture in the combustor, a quantity of fuel supply per unit time to the combustor is increased while increasing the revolution speed of the turbine, to thereby ensuring the ignition of the air-fuel mixture under various conditions, and depressing the temperature rise of the gas turbine, which may otherwise occur immediately after the ignition.

Gas turbine apparatus and a starting method thereof

A gas turbine apparatus is provided wherein a turbine is driven or rotated by burning a mixture of a fuel and compressed air and supplying a combustion gas generated by the combustion. A flameout determination unit is provided in the apparatus which is adapted to calculate the air/fuel ratio in the air/fuel mixture, correct the calculated air/fuel ratio to calculate a corrected air/fuel ratio which is substantially constant, compare the calculated corrected air/fuel ratio with a predetermined reference air/fuel ratio, and generate a signal indicative of occurrence of a flameout when the corrected air/fuel ratio is smaller than the reference air/fuel ratio. The corrected air/fuel ratio is calculated by calculating a deviation of a compressor discharge pressure of the compressed air from an air compressor, from a predetermined reference pressure, multiplying the pressure deviation by a predetermined constant, and adding the pressure deviation multiplied by the predetermined constant to the calculated air/fuel ratio. In this way, the corrected air/fuel ratio can be maintained substantially constant even if a load increases in steps.

Flame detecting apparatus for gas turbine

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

A radial magnetic bearing apparatus suspends a rotating shaft and stably operates at a level exceeding a bending intrinsic vibration value of the rotating shaft by controlling magnetic forces generated by control coils wound around control magnetic poles. Grooves are provided on the surface of each control magnetic pole facing the rotating shaft, and sensor coils are wound to pass through the grooves in order to detect the position of the rotating shaft in the radial direction. A part of each control magnetic pole may be used as magnetic poles of an inductance-type displacement sensor.

Growing community of inventors

Kanagawa, Japan

Eishi Marui