A method controls a converter assembly which has a line-commutated converter. The line-commutated converter has an alternating voltage terminal which can be connected via a phase conductor to an alternating voltage network. The converter assembly further has a switch module branch which is arranged serially in the phase conductor and which contains a series circuit of switch modules at each of the terminals of which bipolar voltages can be generated which add up to a branch voltage. A connection voltage to a connection point between the switch module branch and the converter is controlled by adjusting an amplitude of a positive sequence component of the branch voltage. The converter assembly is configured to carry out a control method for controlling the converter assembly.

A method controls a converter assembly which has a line-commutated converter. The line-commutated converter has an alternating voltage terminal which can be connected via a phase conductor to an alternating voltage network. The converter assembly further has a switch module branch which is arranged serially in the phase conductor and which contains a series circuit of switch modules at each of the terminals of which bipolar voltages can be generated which add up to a branch voltage. A connection voltage to a connection point between the switch module branch and the converter is controlled by adjusting an amplitude of a positive sequence component of the branch voltage. The converter assembly is configured to carry out a control method for controlling the converter assembly.

Apparatuses including multiple selectable circuit elements are described. In an example, an apparatus may include a power supply configured to output a voltage. The apparatus may further include a controller connected to the power supply and a transmission unit connected to the controller. The transmission unit may be configured to output power. The transmission unit may include comprising an inverter connected to the power supply. The inverter may include a high-side switching element. The transmission unit may further include a circuit element a circuit connected to the power supply. The circuit may be configured to select the circuit element. The circuit may include a switch connected between the inverter and the circuit element. The switch and the high-side switching element may be configured to be driven by the voltage outputted by power supply. The controller may be configured to control the power being outputted by the transmission unit.

Apparatuses including multiple selectable circuit elements are described. In an example, an apparatus may include a power supply configured to output a voltage. The apparatus may further include a controller connected to the power supply and a transmission unit connected to the controller. The transmission unit may be configured to output power. The transmission unit may include comprising an inverter connected to the power supply. The inverter may include a high-side switching element. The transmission unit may further include a circuit element a circuit connected to the power supply. The circuit may be configured to select the circuit element. The circuit may include a switch connected between the inverter and the circuit element. The switch and the high-side switching element may be configured to be driven by the voltage outputted by power supply. The controller may be configured to control the power being outputted by the transmission unit.

Apparatuses including multiple selectable circuit elements are described. In an example, an apparatus may include a power supply configured to output a voltage. The apparatus may further include a controller connected to the power supply and a transmission unit connected to the controller. The transmission unit may be configured to output power. The transmission unit may include comprising an inverter connected to the power supply. The inverter may include a high-side switching element. The transmission unit may further include a circuit element a circuit connected to the power supply. The circuit may be configured to select the circuit element. The circuit may include a switch connected between the inverter and the circuit element. The switch and the high-side switching element may be configured to be driven by the voltage outputted by power supply. The controller may be configured to control the power being outputted by the transmission unit.

Apparatuses including multiple selectable circuit elements are described. In an example, an apparatus may include a power supply configured to output a voltage. The apparatus may further include a controller connected to the power supply and a transmission unit connected to the controller. The transmission unit may be configured to output power. The transmission unit may include comprising an inverter connected to the power supply. The inverter may include a high-side switching element. The transmission unit may further include a circuit element a circuit connected to the power supply. The circuit may be configured to select the circuit element. The circuit may include a switch connected between the inverter and the circuit element. The switch and the high-side switching element may be configured to be driven by the voltage outputted by power supply. The controller may be configured to control the power being outputted by the transmission unit.

Accordingly, the embodiments herein provide a hybrid modular multilevel converter. The hybrid modular multilevel converter includes one or more chain links, one or more high voltage switches and a plurality of inductors. The one or more chain links are formed by sub modules. The one or more high voltage switches are formed by semi-controlled devices or fully controlled or any other suitable semiconductor devices. The plurality of inductors are arranged in the one or more chain links to limit circulating current among the one or more chain links. The one or more chain links are configured to enhance a power handling capability of the hybrid modular multilevel converter.

A power conversion device including a switching element includes: a temperature change estimation unit estimating temperature change in a semiconductor chip containing the switching element; a number calculator calculating the number of power cycles to fracture of the semiconductor chip due to power cycles; and a degradation degree calculator computing a degree of degradation of the semiconductor chip caused by the power cycles. The temperature change estimation unit calculates a maximum value and a minimum value of temperature of the semiconductor chip in one power cycle based on a first threshold of temperature fall allowed when it is determined that the temperature of the semiconductor chip is rising, and a second threshold of temperature rise allowed when it is determined that the temperature of the semiconductor chip is falling. The number calculator calculates the number of power cycles to fracture based on the maximum value and the minimum value.

Provided is a power supply device including a capacitor, a pre-charge circuit and a control circuit. The capacitor is connected in series with a contactor that is connected between an inverter driving a motor and a battery and that switches on or off power supply from the battery to the inverter, and is connected in parallel with the inverter. The pre-charge circuit is connected in parallel with the contactor and pre-charges the capacitor. The control circuit controls the pre-charge circuit and the contactor. The control circuit includes a sensor that measures the voltage of the battery and the voltage of the capacitor, and determines whether the pre-charge is necessary according to whether a ratio of the voltage of the capacitor to the voltage of the battery is equal to or less than a target value.

A switching circuit for a current source inverter includes a first inverter leg, a second inverter leg, and a controller. The first inverter leg includes a first reverse-voltage-blocking (RB) switch, a second RB switch, and a third RB switch that are connected in series between a first bus line and a second bus line. The second inverter leg includes a fourth RB switch, a fifth RB switch, and a sixth RB switch are connected in series between the first bus line and the second bus line. The controller is configured to control a switch between an on-state and an off-state for each RB switch. When in the on-state, a reverse voltage is blocked by a respective RB switch, and a current with a positive polarity is conducted through the respective RB switch. When in the off-state, a voltage and the current are blocked by the respective RB switch.