Patent application number | Description | Published |
20110049991 | UNINTERRUPTIBLE POWER SUPPLY APPARATUS - In an uninterruptible power supply apparatus, a common mode current flowing from nodes (N | 03-03-2011 |
20110051478 | POWER CONVERSION DEVICE - A three-level PWM converter ( | 03-03-2011 |
20110103106 | POWER CONVERSION DEVICE - In a power conversion device, reactors in an AC input filter absorbing a voltage at a carrier frequency of a PWM converter and reactors in an AC output filter absorbing a voltage at a carrier frequency of a PWM inverter include one six-leg six-phase iron core reactor. Accordingly, the device can be reduced in size when compared with a case where the reactors are composed of two four-leg six-phase iron core reactors. | 05-05-2011 |
20110127837 | POWER CONVERSION APPARATUS - A power conversion apparatus includes an inverter for converting DC power to AC power for supply to a load, a converter for converting AC power from an AC power supply to DC power for supply to the inverter, a DC voltage converter for converting a voltage value of power stored in a storage battery to supply DC power from the storage battery to the inverter when power supply from the AC power supply is faulty, and a filter including a reactor and a capacitor, for removing harmonics generated by the inverter. The inverter includes a three-level circuit which is a multi-level circuit. | 06-02-2011 |
20110170322 | POWER CONVERSION DEVICE - A power conversion device includes an inverter for converting DC power to AC power to supply the AC power to a load, a converter for converting AC power from an AC power supply to DC power to supply the DC power to the inverter, a DC voltage converter for converting a voltage value of power stored in a storage battery to supply DC power from the storage battery to the inverter when power supply by the AC power supply is abnormal, and a filter which includes a reactor and a capacitor and removes harmonics generated by the inverter. The inverter includes a three-level circuit constituted of an arm and an AC switch. | 07-14-2011 |
20110299307 | UNINTERRUPTIBLE POWER SUPPLY APPARATUS - An uninterruptible power supply apparatus includes a cooler cooling a converter/chopper circuit and a cooler cooling a PWM inverter. The converter/chopper circuit and the cooler make up one integrated unit. Accordingly, a smaller apparatus can be achieved, compared with a conventional apparatus in which a cooler is provided for each of a converter and a chopper. | 12-08-2011 |
20120013193 | UNINTERRUPTIBLE POWER SUPPLY SYSTEM - In an uninterruptible power supply system, control sections of three uninterruptible power supply units are connected to one another by communication cables to configure one integrated control unit. The integrated control unit brings three switches into conduction if a bias feeding mode is selected by one arbitrary operation section and brings three switches into conduction if an inverter feeding mode is selected. Therefore, there is no need to separately provide an operation section and a control section for operating and controlling all of the uninterruptible power supply units. | 01-19-2012 |
20130163301 | POWER CONVERSION APPARATUS - A power conversion apparatus includes a comparison circuit which compares a determination element related to a loss in the power converter with a switching reference value and outputs a determination instruction when a difference has occurred between them, a determination circuit which outputs a two-level operation switching instruction when the determination element is greater than or equal to the switching reference value, and a switching circuit which, when having received a two-level operation switching instruction, turns off the alternating-current switch and turns on the valve devices in the arm sequentially, thereby bringing the power converter into a two-level operation state. | 06-27-2013 |
20130241585 | INVERTER TEST APPARATUS - There is provided an inverter test apparatus for testing an inverter interconnected with an alternating-current power system, the apparatus including an alternating-current power output unit configured to output alternating-current power, and an alternating-current power controller configured to control the alternating-current power output from the alternating-current power output unit to simulate an alternating-current load of the inverter. | 09-19-2013 |