Patent application number | Description | Published |
20090168474 | POWER CONVERTING DEVICE AND METHOD FOR CONTROLLING THE SAME - In a system to which a fluctuating load is connected, compensating for fluctuation in voltage harmonics at the load connecting point and fluctuation in system current harmonics has been difficult for a power converting device connected in parallel with the load. To resolve the problem, a power converting device connected in parallel with a fluctuating load includes: a Fourier series expansion unit which executes Fourier series expansion to load current by use of a reference sine wave in sync with a system and thereby outputs Fourier coefficients; and a fundamental component calculating unit which calculates a positive phase active fundamental component of the load current from the Fourier coefficients. A current instruction of the power converting device is generated by subtracting the fundamental current from the load current. With the current instruction, the fluctuations in system current harmonics and in voltage harmonics at the connecting point can be compensated for. | 07-02-2009 |
20100321847 | SEMICONDUCTOR POWER CONVERSION APPARATUS - A semiconductor power conversion apparatus capable of protecting an IGBT from an overvoltage by supplying a sufficient gate current to the gate of the IGBT. The IGBT is protected from the overvoltage by connecting clamping elements connected in series between a collector of the IGBT and the gate thereof, and by connecting a resistor to each of different junction points between the clamping elements connected in series. | 12-23-2010 |
20110019442 | POWER CONVERTER - The noise generated from a power converter is suppressed by increasing the noise frequency to a level not lower than the maximum frequency of the human audible range. To obtain the frequency of an output current harmonic component as a noise source which has exceeded the maximum frequency of the human audible range, it is adequate to determine that the frequency of a driving carrier wave for the individual converter cells in the power converter, in which the phases of the carrier wave for the converter cells are mutually shifted by a given value between the converter cells, meets the following equation. | 01-27-2011 |
20110019449 | POWER CONVERTER APPARATUS - A power converter apparatus having a configuration of a plurality of unit cells, including a DC capacitor and semiconductor devices, connected in cascade, includes a variable voltage source that is connected with a DC link, and a unit having a function that initially charges up the DC capacitor in the unit cell alone selected at a time of an initial charge. | 01-27-2011 |
20120026767 | POWER CONVERSION DEVICE - A power conversion device connected with a three-phase power system through a transformer, including unit converters cascade-connected so that reactors are unnecessary, and volume and weight are reduced. The secondary winding of the transformer is an open winding having six terminals. A first converter group, includes a circuit which has three converter arms, which are star-connected, connected to three of the terminals of the secondary winding. A second converter group, having three different converter arms which are star-connected, is connected to three other terminals of the secondary winding. A neutral point (the point where the star connection is made) of the first converter group, and a neutral point of the second converter group are made to be the output terminals of the power conversion device. | 02-02-2012 |
20120113698 | POWER CONVERSION DEVICE - Disclosed is a power conversion device, wherein among the optical fiber cables used in control/communication, at least the majority of high-voltage optical fiber cables with a dielectric strength against the output voltages of a plurality of cells can be eliminated and thus a low-voltage optical fiber cable with a dielectric strength against the output voltage of one cell can be used. Furthermore, here, the length required for the optical fiber cable can be reduced. A controller of the power conversion device comprising a plurality of cascade-connected cells comprises a central controller, and a cell controller with the same potential as each cell, the cell controller being installed in the vicinity of each cell, wherein the central controller and each cell controller are daisy-chained using an optical fiber cable. | 05-10-2012 |
20130148392 | Power Conversion Device - A power conversion device includes at least two legs connected in parallel each of which includes at least two unit converters connected in series, wherein at least one of the legs is formed using at least two kinds of unit converters including a first type unit converter capable of outputting a unipolar voltage and a second type unit converter capable of outputting a bipolar voltage. | 06-13-2013 |
20130279227 | CAPACITOR EMBEDDED BETWEEN BUSBARS, ELECTRIC POWER DEVICE AND ELECTRIC POWER CONVERSION DEVICE - The present invention provides an inter-bus-bar built-in capacitor capable of reducing the size of a capacitor used in an inverter or the like or downsizing the capacitor, and provides power equipment as well as a power converting apparatus. The inter-bus-bar built-in capacitor is provided between a pair of opposing bus bars and includes a high-dielectric-constant material which has a relative dielectric constant of at least 50 when a voltage of 1,000 V is applied at a temperature of 25° C. Thus, it is possible to provide the inter-bus-bar built-in capacitor capable of reducing the size of a capacitor used in an inverter or the like or downsizing the capacitor and provide the power equipment as well as the power converting apparatus. | 10-24-2013 |
20140078796 | Power Conversion Apparatus and Control Method Thereof - In the present invention, provided is a power conversion apparatus in which at least one energy storage element and at least one switching element are included, a plurality of series circuits of a transformer winding and an arm in which one or a plurality of at least two-terminal unit converters which depend on ON/OFF of the switching element and supply a zero voltage or a voltage depending on a voltage of the energy storage element are connected in series are connected in parallel, and a multi-phase power source or a multi-phase load is connected to another winding of the transformer, and the parallel-connection point is set as a DC terminal, and which includes means for controlling a current flowing through each of the arms to have a phase and amplitude different from each other. | 03-20-2014 |
20140169048 | POWER CONVERSION DEVICE - A power conversion device is provided which includes a plurality of series circuits each formed of a voltage source and a controlled current source. At least two of said series circuits formed of the voltage source and the controlled current source are connected in parallel. Further, parallel connection points of the series circuits connected in parallel form output terminals. | 06-19-2014 |