Abb Research Ltd.

Abb Oy

Abb Technology Oy

Abb Schweiz Ag

Steffen Bernet

Rodrigo Alonso Alvarez Valenzuela

Ignacio Lizama

Thomas Br&uuml;ckner

Peter Karl Steimer

Matti Laitinen

Antonio Coccia

Karsten Fink

Matti Laiteinen

Rodrigo Alvarez

A method and apparatus are provided for balancing currents of two or more parallel-connected power semiconductor switches during an on-state of the switches. A control terminal of each switch is driven by a driver unit. The method includes determining ratios between the currents through the switches. For each switch, the method includes controlling the voltage at the control terminal on the basis of the ratios by controlling a level of a supply voltage of the driver unit of the switch, and after a turn-on commutation transient, modulating the output of the driver unit. The duty cycle of the modulation is controlled to minimize the time required for the transition of the voltage at the control terminal from the one voltage level to another.

Method and apparatus for balancing currents

Unique systems, methods, techniques and apparatuses of a reverse-conducting IGBT (RC-IGBT) are disclosed. One exemplary embodiment is a circuit comprising a series connection of controllable switch components where at least one of the controllable switch components is an RC-IGBT. The circuit is operated by applying a pre-trigger pulse to the gate electrode of the RC-IGBT during reverse conduction of the RC-IGBT at a first time instant, the pre-trigger pulse corresponding to a turn-on gate pulse. Next, a turn-on gate pulse is applied at a second time instant to the other controllable switch component of the series connection for controlling the other controllable switch component to a conductive state such that the pre-trigger pulse and the turn-on gate pulse overlap, and ending the pre-trigger pulse after a delay time at the third time instant. The delay time is the time period when the turn-on gate pulse and the pre-trigger pulse overlap.

Control of reverse-conducting IGBT

A method and an arrangement are provided for balancing the switching transient behavior of parallel connected power semiconductor components. The method includes providing a switch signal to the parallel connected power semiconductor components for changing the state of the components, forming control signals for each of the parallel connected components from the switch signal, and determining, during the change of state of the power semiconductor component, the voltage induced to an inductance in the main current path of the component in each of the parallel connected components. The method also includes comparing each of the induced voltages with a predetermined threshold voltage, measuring time differences between the time instants at which the induced voltages crosses the threshold voltage, and modifying one or more of the control signals on the basis of the measured time differences in the respective following state change for balancing the switching transient behavior.

Current balancing of parallel connected semiconductor components

An open-loop and closed-loop control method is proposed for a single-phase or polyphase three-point converter which is connected to a DC voltage intermediate circuit, having two series-connected main switches/inverse diodes between each DC voltage connection and each load connection. The common junction point of the two inner main switches forms the load connection. An active clamped switch with an inverse diode is connected between each common junction point of an inner main switch and an outer main switch and the center tap of the DC voltage intermediate circuit. As a result of which, two possible paths are formed for connecting a load connection to the center tap. Irrespective of the direction of the load current, at least one of the two active clamped switches (T5, T6) is connected to the center tap together with at least one inner main switch for connection of a load connection. The provides a circuit that can carry the current deliberately through the upper path, the lower path, or through both paths, to the center tap during a null state.

Open-loop and closed-loop control method for a three-point converter with active clamped switches, and apparatus for this purpose

A three-point converter with NPC diodes disposed between bridge halves and a center tap of an intermediate circuit is proposed. A decoupling network is provided for the upper bridge half, a first input of which decoupling network is connected to a positive pole of the intermediate circuit and a first output of the decoupling network is connected to a positive pole of the three-point converter. Furthermore, provision is made of a further decoupling network for the lower bridge half, a first input of the further decoupling network is connected to a negative pole of the intermediate circuit and a first output of the further decoupling network is connected to a negative pole of the three-point converter. The remaining inputs of both of the decoupling networks are connected to the center tap of the intermediate circuit. The remaining outputs of both of the decoupling networks are connected via the NPC diodes to the upper and lower bridge halves. A commutation voltage for the main switches of the upper and lower bridge halves is decoupled from a halved intermediate circuit voltage (V,/2) independently of one another by the decoupling networks.

Growing community of inventors

Dresden, Germany

Steffen Bernet