Patent application number | Description | Published |
20080303619 | PROTECTION OF PERMANENT MAGNENTS IN A DC-INDUCTOR - A DC inductor comprising a core structure ( | 12-11-2008 |
20080303620 | DC Inductor - A DC inductor comprising a core structure ( | 12-11-2008 |
20090059625 | SINGLE-PHASE TO THREE-PHASE CONVERTER - Single-phase to three-phase converter comprising a rectifier stage, a DC link and an inverter stage, wherein the rectifier comprises a filter choke, one controllable switch for power factor correction, rectifying diodes arranged in a diode bridge configuration having input terminals and output terminals, the controllable switch being connected to the output terminals of the diode bridge, an upper blocking diode arranged between the positive output terminal of the diode bridge and the positive input of the DC link and a lower blocking diode arranged between the negative output terminal of the diode bridge and the negative input of the DC link, the DC link comprises a capacitor bank connected between the DC link, which capacitor bank has a center point. The inverter stage comprises three phase outputs, two of which are formed with a series connections of controllable switches arranged between the DC link for switching either positive voltage or negative voltage of the DC link to the phase outputs, and one phase output is formed of the voltage of the center point of the capacitor bank, and in that the center point of the capacitor bank is configured to be optionally connected to the neutral line of the single-phase AC input by using a connection switch element providing thereby doubled voltage to the DC link. | 03-05-2009 |
20090134714 | COMPENSATION OF HARMONICS OF ELECTRICAL NETWORK - A system and a method for compensating harmonic components or a reactive power of an electrical network. The system comprises a measurement unit ( | 05-28-2009 |
20090267545 | METHOD AND ARRANGEMENT IN CONNECTION WITH A BRAKE CHOPPER - A method of controlling a brake chopper and a control arrangement, the brake chopper being connected between the positive and the negative rails of an intermediate voltage circuit feeding an inverter bridge, wherein current measurement means are arranged between a DC voltage source and the brake chopper and adapted to measure DC current flowing in the intermediate voltage circuit, which method comprises steps of forming with the inverter bridge an output voltage to a load connected to the output of the inverter bridge, determining a time instant when the DC current of the intermediate circuit is sampled, and preventing the use of the brake chopper at the determined time instant. | 10-29-2009 |
20100142238 | METHOD AND DEVICE IN FREQUENCY CONVERTER - A method in connection with a frequency converter for correcting the power factor of the frequency converter, and a power factor correction unit. The method includes connecting the power factor correction unit between a rectifier bridge of the frequency converter and the supplying AC voltage network, generating with the power factor correction unit DC voltage from the AC voltage of the supply network and feeding the generated DC voltage to the frequency converter via the rectifier bridge of the frequency converter. | 06-10-2010 |
20110074489 | INVERTER - A two-level or multi-level inverter are supplied with a positive auxiliary voltage (Ug+) and a negative auxiliary voltage (Ug−). A bootstrap technique provides a first positive auxiliary voltage and a first negative auxiliary voltage from the supplied potentials. The bootstrap technique provides at least one additional negative auxiliary voltage to a switch driver of at least one semiconductor switch from the first negative auxiliary voltage. At the start up of an inverter, the inverter can perform a startup sequence to provide auxiliary voltages to the respective auxiliary voltage inputs of the switch drivers by turning the power semiconductors sequentially on and off. | 03-31-2011 |
20120092914 | SWITCHING BRANCH FOR THREE-LEVEL RECTIFIER AND METHOD FOR CONTROLLING SWITCHING BRANCH FOR THREE-LEVEL RECTIFIER - A switching branch for a three-level rectifier and a method for controlling a switching branch for a three-level rectifier are provided. The switching branch includes a first diode and a second diode connected in series, a third diode and a fourth diode connected in series, a first controllable switch connected between a neutral DC output pole and a connection point between the first and the second diode, and a second controllable switch connected between the neutral DC output pole and a connection point between the third and the fourth diode. The switching branch includes means for controlling the first controllable switch to be in a conductive state during a reverse blocking state of the first diode and the second diode, and means for controlling the second controllable switch to be in a conductive state during a reverse blocking state of the third diode and the fourth diode. | 04-19-2012 |
20120120698 | SWITCHING BRANCH FOR THREE-LEVEL CONVERTER AND METHOD FOR CONTROLLING SWITCHING BRANCH OF THREE-LEVEL CONVERTER - Exemplary embodiments for controlling a switching branch for a three-level converter, and a switching branch are disclosed. A first semiconductor switch and a second semiconductor switch, a first diode and a second diode, a third semiconductor switch and a fourth semiconductor switch, a third diode, and a fourth diode, a fifth semiconductor switch and a sixth semiconductor switch, a fifth diode, and a sixth diode, and a control arrangement for controlling the semiconductor switches are provided. The first semiconductor switch, the first diode, the fifth semiconductor switch and the fifth diode reside in a first switching branch-specific semiconductor module, and the fourth semiconductor switch, the fourth diode, the sixth semiconductor switch and the sixth diode reside in a second switching branch-specific semiconductor module. | 05-17-2012 |
20120320647 | SWITCHING BRANCH FOR THREE-LEVEL RECTIFIER, AND THREE-PHASE THREE-LEVEL RECTIFIER - An exemplary switching branch for a three-level rectifier includes a first diode and a first semiconductor switch connected in series between a positive direct voltage pole and a neutral direct voltage pole, a second diode and a second semiconductor switch connected in series between a negative direct voltage pole and the neutral direct voltage pole as well as a thyristor and a third diode connected in series between a connection point between the first diode and the first semiconductor switch and a connection point between the second diode and the second semiconductor switch in such a manner that a connection point between the thyristor and the third diode is connected to an alternating voltage pole of the switching branch. | 12-20-2012 |
20140268940 | METHOD FOR CONTROLLING SWITCHING BRANCH OF THREE-LEVEL CONVERTER AND SWITCHING BRANCH FOR THREE-LEVEL CONVERTER - Exemplary embodiments are directed to a method for controlling a switching branch of a three-level converter to enter a stop state. The switching branch including a first semiconductor switch and a second semiconductor switch, a first diode and a second diode, a third semiconductor switch and a fourth semiconductor switch, a third diode, and a fourth diode, a fifth semiconductor switch and a sixth semiconductor switch, a fifth diode, and a sixth diode, and a manner of controlling the semiconductor switches. When the switching branch is set to enter a stop state, current flowing in a main circuit of the switching branch is transferred in a controlled manner to diodes that conduct the current, when all the semiconductor switches of the main circuit of the converter are turned OFF. | 09-18-2014 |