Abstract: In a power converter which performs power conversion between plural-phase AC and DC, variation in voltage of the DC capacitor in each converter cell is detected, and when the variation exceeds a predetermined value, a DC voltage command value as a control target value in a DC voltage control unit which controls DC voltage between DC buses is corrected by being increased or decreased. Thus, when AC grid failure occurs, the capacitor voltage of each converter cell is maintained and the operation continuity is improved.

Abstract: An image pickup unit includes: a circuit substrate electrically connected with an image pickup device that detects an image of an object, the circuit substrate including a land at least on a surface thereof; a connecting member having conductivity and fixed to the circuit substrate; a wiring connecting portion provided on the connecting member; a substrate connecting portion extended bent from a side portion of the wiring connecting portion, and electrically connected to a land; and a wiring configured to be connected to the wiring connecting portion and electrically connected to the land through the connecting member.

Abstract: A power conversion device includes: a DC current calculation unit for calculating a circulating current component for each phase which circulates between the phases through first arms and/or second arms not via an AC power supply and a DC power supply; and a circulating current control unit for controlling the circulating current component for each phase so as to follow a predetermined circulating current command value, thereby reliably suppressing variation in voltages of DC capacitors of unit cells among the phases even in such a case where an impedance is additionally inserted in a DC circuit.

Abstract: An electric power conversion device includes a power conversion unit and a converter control unit. The power conversion unit includes three arms connected to an AC circuit. The converter control unit includes a phase DC voltage control unit, a negative sequence current command value calculation unit, an output current control unit, a circulating current control unit, a voltage command value calculation unit, and a gate signal generation unit, and imbalance of cell DC capacitor voltages among phases due to grid imbalance is controlled by circulating current and negative sequence current.

Abstract: Each phase arm of a power conversion device includes at least one converter cell connected in series. For each converter cell, an element driving unit is provided which turns on one switching element in the converter cell as a startup element. The element driving unit is supplied with power from a DC capacitor, and when voltage of the DC capacitor exceeds startup voltage Vsh, turns on the startup element. Thus, at the time of startup of the power conversion device, the DC capacitor in each converter cell is initially charged to desired voltage.

Abstract: An endoscope includes: a first lens located at a distal-most position, a part of the first lens being exposed outside; a movable lens barrel configured to be able to move, and configured to hold a movable lens disposed on a proximal end side with respect to the first lens; an actuator unit including a coil that drives the movable lens barrel and generates heat by receiving a supply of electric power; and a control section that outputs first electric power to the coil when holding the movable lens barrel at a predetermined position, and outputs second electric power larger than the first electric power to the coil when conducting heat generated from the coil to the first lens at the predetermined position.

Abstract: A power conversion device includes: a DC current calculation unit for calculating a circulating current component for each phase which circulates between the phases through first arms and/or second arms not via an AC power supply and a DC power supply; and a circulating current control unit for controlling the circulating current component for each phase so as to follow a predetermined circulating current command value, thereby reliably suppressing variation in voltages of DC capacitors of unit cells among the phases even in such a case where an impedance is additionally inserted in a DC circuit.

Abstract: A sintered friction material for use in a high-speed railway is manufactured using a Cu alloy powder produced using an atomizing method from a Cu alloy containing 0.1 to 2.0 mass % of Fe. This friction material has both sufficient high strength and high thermal conductivity.

Abstract: A power converting apparatus is configured with single-phase sub-converters (4) connected to AC input lines of individual phases of a three-phase main converter (3) in series therewith. In a control device (12) for performing output control of the power converting apparatus, a current command value calculating circuit (20) which adjusts a DC voltage command given to the main converter (3) so that DC voltages of the sub-converters (4) follow a command and generates AC current commands so that a DC voltage of the main converter (3) follows the DC voltage command is configured with a CPU, and AC currents are controlled by switching output voltage levels of the sub-converters (4) at an AC side thereof so that deviations of instantaneous AC current values from the AC current commands become smaller.

Abstract: A power converting apparatus is configured with single-phase sub-converters (4) connected to AC input lines of individual phases of a three-phase main converter (3) in series therewith. In a control device (12) for performing output control of the power converting apparatus, a current command value calculating circuit (20) which adjusts a DC voltage command given to the main converter (3) so that DC voltages of the sub-converters (4) follow a command and generates AC current commands so that a DC voltage of the main converter (3) follows the DC voltage command is configured with a CPU, and AC currents are controlled by switching output voltage levels of the sub-converters (4) at an AC side thereof so that deviations of instantaneous AC current values from the AC current commands become smaller.

Abstract: A service controller for crowded elevator cars includes an illuminating apparatus (4) furnished in a top part of a car (1) that is configured to illuminate the car (1) interior, at least one elongated light sensor unit (8) constituted by multiple light sensors (10) on a base member (9) and installed along corner regions (7a, 7b) formed between a vertical wall surface (5) of the car and the car's floor surface (6), and a judgment device (11) that is configured to determine whether there is passenger boarding space in the car (1) based on the output of the light sensors (10).

Abstract: A car shock absorber is positioned on a pit floor car between a car guide rail and the pit floor and/or between the car or counterweight and the pit floor. The car shock absorber has a shock absorbing body made of a deformable material in which a recess is formed. A pressing body is continuously engaged in the recess. When a shock load is input to a top part of the pressing body, the load is distributed in a direction perpendicular to inclined pressure and pressure-receiving surfaces, which are the contact surfaces between the pressing body and the shock absorbing body, thereby reducing the shock stress produced in the pit floor.

Abstract: A power converter includes a steady-state controller for outputting a first voltage command such that a detected power value matches a power command, a transient controller for outputting a second voltage command such that a voltage detected before the occurrence of a fault is maintained when the fault occurs, and a voltage command selector for switching the voltage command in such a way that the first voltage command is output when no power fault is detected and the sum of the first and second voltage commands is output when any power fault is detected.

Abstract: This invention provides a power conversion circuit control apparatus which rapidly detects the voltage amplitude and phase of each phase, corrects the output of a current controller by the mean voltage amplitude and mean phase, and corrects, on the basis of the voltage amplitude and phase of each phase, a voltage amplitude command and voltage phase command to be applied to pulse width modulation. The apparatus can suppress an overcurrent even when the AC voltage is unbalanced, and restart the operation without generating any overcurrent when the circuit is to be reactivated.

Abstract: This invention provides a power conversion circuit control apparatus which rapidly detects the voltage amplitude and phase of each phase, corrects the output of a current controller by the mean voltage amplitude and mean phase, and corrects, on the basis of the voltage amplitude and phase of each phase, a voltage amplitude command and voltage phase command to be applied to pulse width modulation. The apparatus can suppress an overcurrent even when the AC voltage is unbalanced, and restart the operation without generating any overcurrent when the circuit is to be reactivated.

Abstract: A reactive power compensator continues operation even when a higher harmonic wave component of an alternating-current power system increases. For an alternating current electric amount indicating one of an alternating voltage and an alternating electric current in an alternating-current power system, the reactive power compensator outputs a changing amount showing a change of the alternating current electric amount. An electric current command limits an electric current command signal based on the changing amount. For example, the changing amount is changed in accordance with the higher harmonic wave component included in the alternating current electric amount.

Abstract: A reactive power compensator continues operation even when a higher harmonic wave component of an alternating-current power system increases. For an alternating current electric amount indicating one of an alternating voltage and an alternating electric current in an alternating-current power system, the reactive power compensator outputs a changing amount showing a change of the alternating current electric amount. An electric current command limits an electric current command signal based on the changing amount. For example, the changing amount is changed in accordance with the higher harmonic wave component included in the alternating current electric amount.

Abstract: A power converter includes a steady-state controller for outputting a first voltage command such that a detected power value matches a power command, a transient controller for outputting a second voltage command such that a voltage detected before the occurrence of a fault is maintained when the fault occurs, and a voltage command selector for switching the voltage command in such a way that the first voltage command is output when no power fault is detected and the sum of the first and second voltage commands is output when any power fault is detected.

Abstract: The present invention provides a power converter system in which forward conversion capacities and reverse conversion capacities of semiconductor power converter apparatuses connected to a D.C. capacitor can be different from one another. The more suitable semiconductor power converter apparatuses can be selected in accordance with various loads. A power converter system includes semiconductor power converter apparatuses including a D.C. capacitor and power devices cooled by a cooling elements having an output terminal connected to a load. The semiconductor power converter apparatuses are connected in parallel with one another through the D.C. capacitor. Each of the power devices includes self-arc-suppressing semiconductor devices and diodes connected in anti-parallel with the self-arc-suppressing semiconductor devices. All of the semiconductor power converter apparatuses have the same circuit configuration.

Abstract: The present invention provides a power converter system with which the forward conversion capacities and the reverse conversion capacities of a plurality of semiconductor power converter apparatuses connected to a D.C. capacitor can be made different from one another, and the more suitable semiconductor power converter apparatuses can be selected in accordance with various loads. In a power converter system which includes at least a plurality of semiconductor power converter apparatuses constituted by a D.C. capacitor and a plurality of power devices cooled by a cooling piece(s) having an output terminal connected to a load, and which the plurality of semiconductor power converter apparatuses are connected in parallel with one another through the D.C.