Abb Schweiz Ag

Abb Technology Ag

Asea Brown Boveri Ab

Abb Technology Ltd

Lars Döfnäs

Roland Siljeström

Ying Jiang-Häfner

Gunnar Asplund

Lennart Harnefors

Mats Hyttinen

Christer Sjöberg

Wim Van-Der-Merwe

Fabienne Chataignere

Kristoffer Nilsson

Rolf Ottersten

Patrik Sandquist

Anders J Pettersson

Annika Lokrantz

Kristoffer STÅLHAMMAR

A method for controlling a first and a second reverse-conducting insulated gate bipolar transistor (RC-IGBT), electrically connected in series, is disclosed. A collector of the first RC-IGBT is electrically connected to a positive pole of a direct current voltage source, and an emitter of the second RC-IGBT is electrically connected to a negative pole of the DC voltage source. Further, an emitter of the first RC-IGBT is electrically connected to a collector of the second RC-IGBT to form an alternating current terminal. A gate voltage is applied to respective gates of the first and second RC-IGBTs, wherein the gate voltage is controlled based on a magnitude and a direction of an output current on the AC terminal and on a command signal alternating between a first and a second value.

RC-IGBT switching pulse control

A voltage source converter includes a black start control unit and cells, where each cell includes a first switch between a first end of a cell capacitor and a first cell terminal, a second switch between a second end of the cell capacitor and the first cell terminal, where a second cell terminal is provided via the first or the second end of the cell capacitor, a first power supply unit and a second power supply unit, where the black start control unit is configured to perform, after the initial application of a DC voltage to a cell terminal of a cell and the subsequent initial charging of the chargeable power supply unit of one of the switches, charging of an uncharged power supply unit of the other switch through repeatedly turning on and off the switch with initially charged power supply unit.

Black start of a multilevel voltage source converter

A method and a device to discharge cell capacitors in a cell based voltage source converter. Each cell has switching elements in half bridge or full bridge configuration and a capacitor in parallel to the half or full bridge. Each cell has two terminals, whereof at least one is between two switching elements. The converter has AC and DC terminals, with the possibility to connect each of the terminals to ground, via a further switching element. A resistor is implemented into at least one of the ground connections. To discharge to capacitors, the switching elements in the respective cells are configured such, that the capacitor is in parallel connection to the terminals. The capacitors are thus discharged via the resistor to ground.

Capacitor discharge in a cell based voltage source converter

A device for converting a DC voltage into an AC voltage and vice versa comprises a control system to control the voltage conversion and at least one phase leg () with a first (Uvp) voltage source connected in series between a first DC terminal () and a first AC terminal () and with a second (Uvn) voltage source connected in series between the first AC terminal () and a second DC terminal (). Each of the voltage sources comprises at least a first and a second submodule () in series-connection, where each submodule () comprises at least two power electronic switches () connected in parallel with at least one capacitor (). The control system comprises a central control unit () and at least two subunits (), where the central control unit () transmits to each subunit () a reference AC voltage (ua_ref) and a switching carrier signal (s_sw) and where each subunit () controls the switching of the power electronic switches () of one of the submodules () according to a PWM pattern so that each time the switching carrier signal (s_sw) crosses the reference AC voltage (ua_ref) either the voltage across the capacitor () or a zero voltage are applied to output terminals () of the corresponding submodule ().

Power converter with distributed cell control

An apparatus for controlling a voltage source converter with at least two bridges of semiconducting self commutating elements connected in anti-parallel with a diode, including circuitry for producing a switching control pulse train to form a fundamental frequency, circuitry for effecting a switching order and circuitry for detecting a switching event.

Voltage source converter

Recovery of transmitted power in an installation for transmission of

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Ludvika, Sweden

Lars Döfnäs