A control system includes a control unit. When turning a bidirectional switch element ON, the control unit controls the bidirectional switch element to cause a time lag between a first timing and a second timing. The first timing is a timing when a voltage equal to or higher than a threshold voltage is applied to one gate electrode selected from a first gate electrode and a second gate electrode. The one gate electrode is associated with one source electrode selected from a first source electrode and a second source electrode and having a lower potential than the other source electrode. The second timing is a timing when a voltage equal to or higher than a threshold voltage is applied to the other gate electrode associated with the other source electrode having a higher potential than the one source electrode.

An apparatus according to an embodiment includes an upper and lower arm connected between a high and a low potential end; a first capacitor connected at one end to the high potential end; a second capacitor connected at one end to the low potential end; a first regenerative rectifier circuit connected to another end of the first capacitor; a second regenerative rectifier circuit connected to another end of the second capacitor; a first conversion circuit to cause energy stored in the first capacitor to be discharged; and a second conversion circuit to cause energy stored in the second capacitor to be discharged.

A first capacitor and a second capacitor are connected in series through a neutral point on the DC side of an inverter. A first converter receives an input voltage from a power source and outputs a first DC voltage to the first capacitor. A second converter receives a common input voltage and outputs a second DC voltage to the second capacitor. A control circuit controls the first converter such that the first DC voltage is controlled in accordance with a preset first voltage command value and controls the second converter such that the second DC voltage is controlled in accordance with a second voltage command value set equivalent to the first voltage command value.

A modulator for a flying-capacitor type multilevel converter receives, at an input, a time-variant reference signal and provides, at an output, a sequence of target levels, to provide switching signals for switching between discrete output levels of the multilevel converter according to the shape of the reference signal. The modulator determines a critical level as an intermediate output level of the multilevel converter which is closest to the level of the reference signal; and outputs only target levels corresponding to output levels different from the critical level.

A switching circuit for a voltage source converter includes a string of series-connected switches and a string of capacitors. A first conductor interconnects a first end of the string of series-connected switches with a first end of the string of capacitors at a first switch and a second conductor interconnects a second end of the string of series-connected switches with a second end of the string of capacitors at a second switch. A first string of components is connected between the first end of the string of series-connected switches and the first end of the string of capacitors and includes a snubber component for the first switch. A second string of components is connected between the second end of the string of series-connected switches and the second end of the string of capacitors and includes a snubber component for the second switch.

A switching circuit for a voltage source converter includes a string of series-connected switches and a string of capacitors. A first conductor interconnects a first end of the string of series-connected switches with a first end of the string of capacitors at a first switch and a second conductor interconnects a second end of the string of series-connected switches with a second end of the string of capacitors at a second switch. A first string of components is connected between the first end of the string of series-connected switches and the first end of the string of capacitors and includes a snubber component for the first switch. A second string of components is connected between the second end of the string of series-connected switches and the second end of the string of capacitors and includes a snubber component for the second switch.

A power semiconductor module has a substrate that has an electrically non-conductive insulating layer and a first metal layer on the insulating layer and forms conductor tracks, with power semiconductor components arranged on the first metal layer and electrically connected to the first metal layer and having a DC voltage connection device that has a first, second and third flat conductor connection element that are arranged on an end region of the power semiconductor module and that are electrically conductively connected to the first metal layer. During operation, the first and second flat conductor connection elements have a first electrical polarity and the third flat conductor connection element has a second electrical polarity.

A power semiconductor module has a substrate that has an electrically non-conductive insulating layer and a first metal layer on the insulating layer and forms conductor tracks, with power semiconductor components arranged on the first metal layer and electrically connected to the first metal layer and having a DC voltage connection device that has a first, second and third flat conductor connection element that are arranged on an end region of the power semiconductor module and that are electrically conductively connected to the first metal layer. During operation, the first and second flat conductor connection elements have a first electrical polarity and the third flat conductor connection element has a second electrical polarity.

A method includes charging a capacitor of a power inverter to a direct current (DC) input voltage provided at an input terminal of the power inverter. The capacitor has a first terminal and a second terminal. The method also includes providing a first voltage at an output terminal of the power inverter at a first time by controlling one of either a set of input switches configured to selectively couple the first and second terminals to either the input terminal or to a ground terminal, or an output switch configured to selectively couple the output terminal to either the first terminal or the second terminal. The method further includes providing a second voltage at the output terminal at a second time by controlling the other of the set of input switches and the output switch.

A power converter contains at least one phase module which has a plurality of modules which are electrically connected in series. Each module has a first electrical module connection, a second electrical module connection, a first electronic switching element, a second electronic switching element and an electrical energy storage device. The phase module is assigned at least one controllable voltage source which is suitable for generating a compensation voltage in response to a corresponding actuation, the compensation voltage has a time profile such that it reduces an error voltage generated by the switching of the first electronic switching elements and the second electronic switching elements of the module.