Abstract: [Summary] [Object] To suppress warpage of a ceramic substrate, and to prevent a reduction in radiation efficiency. [Means for Settlement] A power semiconductor module includes a module casing fitted with a radiator, and a common unit retained by the module casing. The common unit has: a ceramic substrate having a circuit surface disposed with a semiconductor element, and a radiation surface brought into abutting contact with the radiator; and a package formed by exposing the radiation surface and sealing the circuit surface with heat resistant resin. The circuit surface and the radiation surface are respectively formed of metal layers 51 formed on the ceramic substrate, and the metal layer 51 forming the radiation surface has: by forming a buffer pattern 512 including a groove part extending along a circumferential part thereof, a radiation pattern 510 formed on an inner side of the buffer pattern 512; and an outer peripheral pattern 511 formed on an outer side of the buffer pattern 512.

Abstract: [Object] To incorporate more semiconductor elements in a small-sized lightweight power semiconductor module provided in an arc discharge device. [Means for Settlement] A power supply unit of an arc discharge device includes a semiconductor module 1, and a radiator fitted onto the semiconductor module 1. The semiconductor module 1 includes a module casing 2, and common units 3a to 3c retained by the module casing 2. Each of the common units 3a to 3c has: a ceramic substrate 50 having a circuit surface disposed with a semiconductor element 54, and a radiation surface on a side opposite to the circuit surface; and a package 35 that exposes the radiation surface, and seals the circuit surface with heat resistant resin. The radiator is fitted onto the module casing 2 to be thereby brought into abutting contact with all of the radiation surfaces of the common units 3a to 3c. Based on such a configuration, more semiconductor elements can be incorporated in a small-sized lightweight power semiconductor module.

Abstract: A photovoltaic inverter that can respond to changes in temperature and the amount of sunlight and that can automatically start up is provided, which has a simple configuration and is inexpensive. The photovoltaic inverter has a first voltage detection means for detecting an output voltage of a photovoltaic panel; a current detection means, a control means and a driving means. It further has a model voltage storage means for storing a model voltage table of inverter start-up kick voltages produced based on variation values of an amount of sunlight, a model voltage read-out means, a second voltage detection means for detecting an inverter start-up kick voltage, and an inverter start-up control means.

Abstract: Energy loss due to driving a plurality of power supply units simultaneously in a low-current region is prevented, and a more stable load current is obtained. The generation of a load current in a small-current region from a pilot arc current is handled solely by the power supply unit U1, the remaining (N?1) power supply units U2 through U4 are driven when the small-current region is exceeded, and a current that is the composite of all the currents is fed to the load, whereby a stable plasma arc power supply is obtained in which power consumption in the low-current region is reduced.

Abstract: A method for artificially generating the output characteristic of a solar photovoltaic power generation module, and a solar photovoltaic power generation simulator power-supply apparatus having that output characteristic with the internal power loss reduced. The solar photovoltaic power generation simulator power-supply apparatus includes an IV storing means for storing, as IV curves, the voltage/current characteristics of solar photovoltaic power generations; an IV reading means; and means for generating an IV characteristic as an output target value of automatic control. The solar photovoltaic power generation simulator power-supply apparatus reads a designated particular IV curve from among the stored IV curves to generate a control signal for holding V associated with I on this curve, and supplies this control signal to a semiconductor switching element, which controls the power, thereby artificially generating a solar photovoltaic power generation output characteristic.

Abstract: A plasma arc power supply with a simple structure and its control method enable shifting from a pilot arc to a main arc. A plasma arc power supply used in a plasma arc apparatus that processes a workpiece by forming a pilot arc between a main electrode and a nozzle electrode and subsequently forming a main arc between the main electrode and the workpiece includes N direct current power supply units (N?2) having negative terminals connected to the main electrode and positive terminals to the workpiece, and a switch between the fourth power supply unit and the workpiece. The fourth power supply unit is connected to cause the nozzle electrode to have an opposite polarity to the main electrode. When the switch is open, the fourth power supply unit supplies a small current between the main electrode and the nozzle electrode while forming a pilot arc between them.

Abstract: Lighting of a discharge lamp is controlled in a manner to reduce deterioration of the discharge lamp subjected to high temperature and extend the lifetime of the discharge lamp. A method for controlling lighting of the discharge lamp includes a first constant current control process (period T1, which corresponds to steps S3 and S4) in which constant current control is executed by supplying a first current to the discharge lamp, a second constant current control process (period T3, which corresponds to steps S7 and S8) in which constant current control is executed by supplying a second current greater than the first current to the discharge lamp after the first constant current control process, and a constant power control process (period T4) in which constant power control is executed after the second constant current control process.

Abstract: The present invention is directed to realize an optimum lamp control with an inexpensive configuration in a discharge lamp light-up control apparatus. A constant current control unit controls light-up of a discharge lamp by transmitting a control signal to an inverter and includes: a storage for storing lamp characteristics of the discharge lamp; and a CPU for obtaining information indicative of a type of the discharge lamp attached, reading the lamp characteristics from the storage based on the obtained type information, and transmitting a control signal to the inverter so that an output corresponding to the read lamp characteristics are obtained.

Abstract: Energy loss due to driving a plurality of power supply units simultaneously in a low-current region is prevented, and a more stable load current is obtained. The generation of a load current in a small-current region from a pilot arc current is handled solely by the power supply unit U1, the remaining (N?1) power supply units U2 through U4 are driven when the small-current region is exceeded, and a current that is the composite of all the currents is fed to the load, whereby a stable plasma arc power supply is obtained in which power consumption in the low-current region is reduced.

Abstract: A voltage boosting power supply, wherein a commercial power supply of 100 volt a.c., for example, is used as its primary power source, the input from the power source is accumulated in a capacitor and the accumulated power is then converted into a boosted a.c. power for delivery by means of an invertor, and which is provided with a storage battery as a preliminary power source for protection against power failure and arranged to disconnect the a.c. power supply from the capacitor and, instead, connect the battery across the capacitor through a high frequency switching element by switch means which operate in response to a power failure signal from a power failure detector. Accordingly, the output voltage of the battery is boosted by the capacitor and then applied to the invertor and, therefore, the output voltage can be raised without increase of the capacity of the battery and consequent increase in the size and weight of the device.

Abstract: An inverter controlled DC arc welder of consumable electrode type includes an input rectifier for rectifying AC input power, an inverter for converting the rectifier output to high frequency AC power, an output transformer for stepping down the inverter output voltage, and an output rectifier for rectifying the transformer output voltage to provide a DC output voltage to be applied to a welder load. The welder further includes means for detecting current flowing through the welder load to produce a detection signal, a differentiator circuit for differentiating the detection signal, and correction means for correcting a predetermined reference voltage in accordance with the differentiator output voltage. Feedback control means controls the inverter in accordance with the difference between the transformer output and the corrected reference voltage.

Abstract: An arc welder provided with a low frequency square waveform a.c. power supply as a main power supply for welding in order to improve its power of recovering an arc which may go out at the time of polarity transition of a welding load and an auxiliary d.c. power supply for super-posing its output upon the input of the main power supply to further improve the recovering power, in which a switching element is inserted in a supply path of the output of the auxiliary d.c. power supply and the switching element is put in conduction by a suitable control device only for a necessary shortest arc recovery time in order to reduce a power loss due to continuous supply of the auxiliary d.c. output.

Abstract: An arc welder which can be used with either a high voltage a.c. power supply of a certain voltage or a low voltage a.c. power supply of about a half of said voltage, such as 400 or 200 volts, for example, and which is provided with a circuit configuration in which an input a.c. voltage is rectified by a rectifier and smoothed by a pair of capacitors and the resultant d c. power is converted by an invertor into a high frequency a.c. power which is reduced in voltage by an output transformer and then rectified again, and arranged to discriminate the input a.c. voltage and switchingly connect these capacitors in series or parallel between both ends of the input rectifier, thereby automatically conforming the circuit to both high and low supply voltages.

Abstract: A consumable electrode type d.c. arc welder including an invertor, which is arranged to rectify an a.c. power from a power supply, once convert a resultant d.c. power into a high frequency a.c. power by the invertor and again rectify it to obtain a d.c. power for welding, and provided with means for detecting a current flowing through its welding load to certainly discriminate shortening and arcing states between a welded base material and a welding electrode rod and controlling the invertor with a resultant discrimination signal to reduce its output voltage during the shortening period, thereby preventing spattering produced by an over-current.

Abstract: The method and apparatus for manufacturing an artificial tooth crown which involves the formation of a metal crown, coating the crown with porcelain materials and subjecting the coated crown to high frequency vibrations of the order of 15 to 50 Hz to condense the porcelain materials and remove air and liquid therefrom prior to firing.