Abstract: 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.

Abstract: The present invention relates to a dry vacuum pump unit capable of achieving ultimate pressure of about 1 Pa. The vacuum pump unit includes a main pump (15) disposed at an outside-pressure side, and a booster pump (16) disposed at a vacuum side. The booster pump (16) and the main pump (15) are coupled in series. The booster pump (16) has a higher pumping speed than that of the main pump (15). Each of the main pump (15) and the booster pump (16) includes a pair of pump rotors (52a and 52b), a casing (50) having an inlet port and an outlet port, and a pair of magnet rotors (54 and 54) rotatable with the pair of pump rotors.

Abstract: A screw pump includes a pair of screw rotors (2a, 2b) having teeth which are held in mesh with each other for drawing and discharging a fluid by rotating the screw rotors (2a, 2b) synchronously in opposite directions. The teeth of the screw rotors (2a, 2b) have the same shape as each other and are coiled helically in opposite directions. The teeth of the screw rotors (2a, 2b) have an axial tooth profile which allows a pair of facing teeth surfaces T of the screw rotors (2a, 2b) to be brought into contact with each other only at a pitch line P when the pair of facing teeth surfaces T are brought into contact with each other.

Abstract: An electric power supply apparatus includes a distributed power generator such as a gas turbine generator and a power converter such as an inverter apparatus for converting electric power generated by the distributed power generator into AC electric power (alternating-current power) having a required frequency and a required voltage and supplying the AC electric power to a load. The electric power supply apparatus further includes a control unit having output voltage vs. output current characteristics for determining an output voltage corresponding to an output current of the power converter. The output voltage vs. output current characteristics has a first dropping characteristic for causing output electric power of the electric generator to be limited, between a first output current exceeding a power generation capability of the electric generator and a second output current exceeding a power converting capability of the power converter.

Abstract: 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.

Abstract: An etchant and a method for roughening a copper surface each capable of permitting copper with roughened surface which exhibits acid resistance and permits a copper conductive pattern and an outer layer material to be firmly bonded to each other therethrough in manufacturing of a printed wiring board to simplify the manufacturing. The etchant may contain an oxo acid such as sulfuric acid, peroxide such as hydrogen peroxide and an auxiliary component such as an azole and chlorine. The azole may comprise benzotriazole (BTA). The chlorine may be in the form of sodium chloride (NaCl). The etchant permits a copper surface to be roughened in an acicular manner.

Abstract: A DC component detecting circuit (18) detects a small DC component contained in the AC output power of a grid-connection inverter device (12), accurately within a short period of time, and has a simple, small-size, and lightweight configuration. The DC component detecting circuit (18) comprises separators (21, 22) for separating a voltage which is proportional to the output current of the inverter device into voltages in positive and negative half periods, integrators (23, 24) for integrating the separated voltages in the positive and negative half periods, and an adder (25) for adding integral signals in the positive and negative half periods from the integrators (23, 24).

Abstract: The present invention provides a power supply apparatus including a system linkage inverter. The power supply apparatus has a simple facility structure and is capable of accurately supplying a dummy load with excessive electric power that changes from time to time. The power supply apparatus has a system linkage inverter (13) for inversely transforming DC electric power into AC electric power and supplying the AC electric power to a load (17) connected to a system power supply (20), a dummy load (21) connected parallel to the load (17) through a power device (22), a circuit (28) for detecting electric power flowing from the load to the system power in every constant time, a calculating unit (29) for accumulating the detected electric power, and a control unit (30) for turning on and off the power device for the dummy load based on a state value of an electric power flow calculated by the calculating unit.

Abstract: 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 (5) for converting alternating-current power generated by the generator into commercial alternating-current power, and a system-interconnection device (9) for interconnecting output of the inverter device to a commercial AC power supply system (10). 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.

Abstract: 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.

Abstract: A power generating apparatus has a power generator 4 for generating AC power, a gas turbine engine 2 for driving the power generator 4, and an inverter device 5 for converting the AC power into commercial AC power. The power generating apparatus includes an interconnection switch S1 for connecting an output of the inverter device 5 with a commercial AC power supply system, a first voltage detector 46 for detecting a DC power supply voltage Vdc-in of the inverter device 5, and a second voltage detector 33, 45 for detecting a full-wave rectification voltage of the commercial AC power supply system. The power generating apparatus also includes an interconnection control part 18 for closing the interconnection switch S1 when the DC power supply voltage of the inverter device 5 exceeds the full-wave rectification voltage of the commercial AC power supply system.

Abstract: 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 (5) for converting alternating-current power generated by the generator into commercial alternating-current power, and a system-interconnection device (9) for interconnecting output of the inverter device to a commercial AC power supply system (10). 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.

Abstract: A liquid etchant and a method for roughening a copper surface each capable of providing copper with a roughened surface increased in acid resistance regardless of a chlorine ion in a short period of time, to thereby ensure firm adhesion between a copper conductive pattern and an outer layer material during manufacturing of a printed circuit board, resulting in the manufacturing being highly simplified. The liquid etchant includes a main component containing an oxo acid such as sulfuric acid and a peroxide such as hydrogen peroxide. Also, the liquid etchant includes an auxiliary component containing a tetrazole such as 5-aminotetrazole or the like, or a 1,2,3-azole. The liquid etchant permits a copper surface to be roughened in an acicular manner.

Abstract: 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 (5) for converting alternating-current power generated by the generator into commercial alternating-current power, and a system-interconnection device (9) for interconnecting output of the inverter device to a commercial AC power supply system (10). 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.

Abstract: 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.

Abstract: A power generating apparatus has a power generator 4 for generating AC power, a gas turbine engine 2 for driving the power generator 4, and an inverter device 5 for converting the AC power into commercial AC power. The power generating apparatus includes an interconnection switch S1 for connecting an output of the inverter device 5 with a commercial AC power supply system, a first voltage detector 46 for detecting a DC power supply voltage Vdc-in of the inverter device 5, and a second voltage detector 33, 45 for detecting a full-wave rectification voltage of the commercial AC power supply system. The power generating apparatus also includes an interconnection control part 18 for closing the interconnection switch S1 when the DC power supply voltage of the inverter device 5 exceeds the full-wave rectification voltage of the commercial AC power supply system.

Abstract: A liquid etchant and a method for roughening a copper surface each capable of providing copper with a roughened surface increased in acid resistance regardless of a chlorine ion in a short period of time, to thereby ensure firm adhesion between a copper conductive pattern and an outer layer material during manufacturing of a printed circuit board, resulting in the manufacturing being highly simplified. The liquid etchant includes a main component containing an oxo acid such as sulfuric acid and a peroxide such as hydrogen peroxide. Also, the liquid etchant includes an auxiliary component containing a tetrazole such as 5-aminotetrazole or the like, or a 1,2,3-azole. The liquid etchant permits a copper surface to be roughened in an acicular manner.

Abstract: A liquid etchant and a method for roughening a copper surface each capable of providing copper with a roughened surface increased in acid resistance regardless of a chlorine ion in a short period of time, to thereby ensure firm adhesion between a copper conductive pattern and an outer layer material during manufacturing of a printed circuit board, resulting in the manufacturing being highly simplified. The liquid etchant includes a main component containing an oxo acid such as sulfuric acid and a peroxide such as hydrogen peroxide. Also, the liquid etchant includes an auxiliary component containing a tetrazole such as 5-aminotetrazole or the like, or a 1,2,3-azole. The liquid etchant permits a copper surface to be roughened in an acicular manner.

Abstract: An etchant and a method for roughening a copper surface each capable of permitting copper with roughened surface which exhibits acid resistance and permits a copper conductive pattern and an outer layer material to be firmly bonded to each other therethrough in manufacturing of a printed wiring board to simplify the manufacturing. The etchant may contain an oxo acid such as sulfuric acid, peroxide such as hydrogen peroxide and an auxiliary component such as an azole and chlorine. The azole may comprise benzotriazole (BTA). The chlorine may be in the form of sodium chloride (NaCl). The etchant permits a copper surface to be roughened in an acicular manner.

Abstract: The present invention provides a rotary machine integrated with a control device, which is effective to reduce the cost of manufacture of a variable-speed pump or the like, and allows control programs to be easily established at the installation site. The present invention also provides an inverter device suitable for the above mentioned rotary machine. A rotary machine and control device combination comprises a rotary machine such as a pump, a fan, or the like and a control device integral therewith. The rotary machine has an inverter device for operating the rotary machine, a memory for storing a control program for the inverter device and a program for controlling operation of the rotary machine, a CPU operable according to the programs stored in the memory, an input and output unit connected to sensors and switches positioned in the rotary machine, one or more serial ports (14) connected to the CPU (12), and device for rewriting contents stored in the memory (11).