Patent application number | Description | Published |
20080252145 | DC/DC POWER CONVERSION DEVICE - A DC/DC power conversion device includes n-stage circuits comprised of an inverter circuit for driving which is connected between positive terminals and negative terminals of smoothing capacitors, and a rectifier circuit which is connected between positive terminals and negative terminals of smoothing capacitors; a first circuit corresponding to at least one among the n-stage circuits and configured by connecting in parallel cell circuits of m, second circuits corresponding to a plurality of remaining circuits of (n−1) among the n-stage circuits; capacitors for energy transfer connected between middle points of the cell circuits and middle points of the second circuits; and column circuits of m comprised of the cell circuits, the second circuits and the capacitors for energy transfer, wherein the middle points are contact points of high voltage sided elements and low voltage sided elements of the cell circuits and the second circuits; and driving signals for driving the respective column circuits have the same driving cycle and are out of phase with each other. | 10-16-2008 |
20090002054 | GATE DRIVE APPARATUS - A gate drive apparatus including a constant-current-pulse gate drive circuit which creates a gate signal for a switching device as a constant-current output, a constant-voltage-pulse gate drive circuit which creates the gate signal as a constant-voltage output, and a decision/switch circuit which switches the operation of the constant-current-pulse gate drive circuit and the operation of the constant-voltage-pulse gate drive circuit. The variance of switching speeds attributed to the variances of threshold voltages and mirror voltages in a plurality of switching devices which are driven by the gate drive apparatus can be suppressed, and the variance of losses can be minimized. | 01-01-2009 |
20090261793 | DC/DC POWER CONVERTING APPARATUS - Three or more circuits, in which series-connected low-voltage and high-voltage side switches including MOSFETs including parasitic diodes are connected across positive and negative terminals of each of smoothing capacitors, are connected in series. One of elementary series circuits, each including a capacitor and an inductor, is disposed between any adjacent two of the circuits with the elementary series circuits set to have the same period of resonance. The MOSFETs of rectifier circuits are brought into an ON state simultaneously with the MOSFETs of a driving inverter circuit and brought into an OFF state earlier than the MOSFETs of the driving inverter circuit by a period of time not exceeding a time period equal to (period of resonance)/2. A resonance phenomenon of the capacitor and the inductor is used and conduction loss in the rectifier circuits is reduced in DC/DC power conversion performed through charging and discharging operation of the capacitor. | 10-22-2009 |
20100019753 | DC/DC POWER CONVERTING APPARATUS - Three or more circuits including a driving inverter circuit and rectifier circuits are connected in series, each of the circuits including a high-voltage side MOSFET and a low-voltage side MOSFET connected in series as well as a smoothing capacitor having positive and negative terminals between which the MOSFETs are connected. LC series circuits, each including a capacitor and an inductor, are disposed individually between one specific circuit and the other circuits with periods of resonance of the LC series circuits made equal to one another. In performing DC/DC power conversion through charging and discharging operation of the capacitors, a resonance phenomenon of the LC series circuits is used to improve conversion efficiency and achieve a reduction in size of the apparatus structure. | 01-28-2010 |
20100213989 | GATE DRIVING CIRCUIT - To obtain a gate driving circuit in which rising of a constant current of a constant current circuit is fast and power saving is achieved, the gate driving circuit includes: a constant current driving circuit ( | 08-26-2010 |
20110121661 | POWER CONVERSION DEVICE - In a power conversion device which performs DC/DC conversion, an inverter circuit ( | 05-26-2011 |
20110181250 | POWER SUPPLY APPARATUS - A power supply apparatus includes: an AC generator including an AC generating section, and a rectifier for rectifying an AC voltage generated in the AC generating section, and outputting a DC voltage; and a DC/DC converter for converting the output voltage of the rectifier into a DC voltage having a different voltage value, wherein the output voltage of the rectifier is set to be larger than the output voltage of the DC/DC converter in accordance with the rotation speed of the AC generating section and the amount of power supply to an electrical load connected to the DC/DC converter, and is stepped down and outputted by using the DC/DC converter. The power supply apparatus is capable of increasing an output power efficiently. | 07-28-2011 |
20120039045 | POWER MODULE AND METHOD FOR DETECTING INSULATION DEGRADATION THEREOF - A method and device for detecting insulation degradation of a power module, which detects, in advance, degradation of an insulating sheet based on a current change immediately before breakdown of an insulation characteristic from a current value of a current flowing through the insulating sheet, thereby detecting a failure of a power module caused by the degradation of insulation. The device includes: a current detector sampling and detecting a current value of a current flowing through an insulating sheet of the power module at a predetermined time interval; a calculator determining, based on the current value, a state in which the insulation characteristic of the insulating sheet is so degraded that the breakdown is imminent, and outputting a degradation determination result of YES when it is determined that the insulating sheet is in the state immediately before the breakdown; a current storage storing a current value i(n−1) at a previous sampling time point; and an alarm generating an alarm in response to the degradation determination result of YES. The calculator outputs the degradation determination result of YES when a present current value in exceeds ten times the previous current value i(n−1). | 02-16-2012 |
20120092915 | POWER CONVERSION APPARATUS - A power conversion apparatus including: a three-level inverter including bridge circuits each including a first semiconductor switching device and a second semiconductor switching device connected in series, the bridge circuits being connected to a positive terminal and a negative terminal of a DC power supply, and switch circuits having bidirectional characteristics and connected to respective AC output terminals of the bridge circuits which are the connection points between the first semiconductor switching devices and the second semiconductor switching devices, and to an intermediate potential point of the DC power supply; and single-phase inverters each including a plurality of semiconductor switching devices and respectively connected in series to the AC output terminals of the bridge circuits. The sum of an output voltage of the three-level inverter and output voltages of the single-phase inverters is supplied to a load. | 04-19-2012 |
20120120694 | POWER CONDITIONER FOR PHOTOVOLTAIC POWER GENERATION - Power generated by a solar battery of thin-film type is stepped up to a predetermined DC voltage by a step-up chopper circuit, and the predetermined DC voltage is converted into three-phase AC power by an inverter circuit, and the three-phase AC power is supplied to an AC power supply system via an output DC voltage circuit. The solar battery is not grounded, and a negative electrode thereof has a floating capacitance between the negative electrode and the ground. The AC power supply system is configured by three-phase star-connection, and the neutral point is grounded. The output DC voltage circuit includes three batteries, and the batteries are provided, for the respective phases, between the AC power supply system and a sine wave filter connected to the AC output side of the inverter circuit. Therefore, it is possible to prevent acceleration of the deterioration of the solar battery. | 05-17-2012 |
20120126764 | DC/DC POWER CONVERSION APPARATUS - An object of the present invention is to provide a DC/DC power conversion apparatus that can reduce the average power consumption over a wide range of DC voltage ratios. A control circuit ( | 05-24-2012 |
20120158245 | AUTOMOTIVE ELECTRIC POWER SUPPLY SYSTEM - A first DC/DC converter is connected to a higher-voltage output terminal of a rectifier by alternator wiring, a battery that supplies electric power to an on-board load is connected to the first DC/DC converter, a second DC/DC converter is connected to the higher-voltage output terminal of the rectifier by alternator wiring, and an electrical double-layer capacitor is connected to the second DC/DC converter. | 06-21-2012 |
20130021011 | DC/DC POWER CONVERSION APPARATUS - A DC/DC power conversion apparatus includes a reactor connected to a DC power supply and a DC voltage conversion section connected to the reactor. The DC voltage conversion section includes a plurality of switching devices, a charge-discharge capacitor which is charged or discharged by ON/OFF operations of the switching devices, a plurality of diodes which provide a charging route and a discharging route for the charge-discharge capacitor. The DC/DC power conversion apparatus also includes a smoothing capacitor on an output side, which is connected to the DC voltage conversion section and including a plurality of voltage division capacitors connected in series to each other, and a switching device for voltage equalization provided on a connection line provided between the negative terminal of the charge-discharge capacitor and a connection point between the voltage division capacitors. | 01-24-2013 |
20130119961 | DC/DC CONVERTER - In a DC/DC converter, a first operation section calculates a first operation value, based on a difference voltage between an instruction value for a high-voltage-side voltage and a detected value of a high-voltage-side voltage, a second operation section calculates a second operation value, based on a difference voltage between a voltage instruction value for a charge-discharge capacitor and a voltage detected value of the charge-discharge capacitor, and a switching control section obtains a conduction ratio, based on the first operation value and the second operation value, and controls, based on the conduction ratio, switching operations of first to fourth semiconductor circuits, thereby controlling the high-voltage-side voltage, and the voltage of the charge-discharge capacitor. | 05-16-2013 |