A capacitive element has its terminals coupled together by two thyristors electrically in antiparallel. The discharge of the capacitive element is controlled by the application of a gate current to one thyristor of the two thyristors which is in a reverse-biased state in response to a voltage stored across the terminals of the capacitive element. The reverse-biased thyristor responds to the applied gate current by passing a leakage current to discharge the stored voltage.

The present disclosure relates to a sub-module of a power converter, the sub-module capable of allowing failure-causing electric current to bypass the sub-module when a failure occurs in the sub-module. According to an embodiment of the present disclosure, there is proposed a sub-module of a power converter, the sub-module including an energy storage unit, at least one power semiconductor circuit connected, in parallel, to the energy storage unit and configured with a plurality of power semiconductor switches and a plurality of freewheeling diodes, an auxiliary switching element connected to the energy storage unit, turned on when a failure occurs, and thus allowing electric current from the energy storage unit to pass through, and a main switching element connected in series to an output terminal of the auxiliary switching element, arranged between two output terminals connected to one of one or more of the power semiconductor circuits, forced to undergo an induced failure due to application of a voltage stored in the energy storage unit through the auxiliary switching element, internally short-circuited, and thus connecting the output terminals to each other.

Embodiments of the disclosure include an electrical assembly. The electrical assembly can include a converter including a DC side and an AC side, the DC side configured for connection to a DC network, the AC side configured for connection to an AC network, the converter including at least one switching element; a circuit interruption device operably connected to the AC side of the converter; a DC voltage modification device operably connected to the DC side of the converter, the DC voltage modification device including a DC chopper; and a controller configured to selectively control the or each switching element, the circuit interruption device and the DC voltage modification device, wherein the controller is configured to be responsive to a converter internal fault by carrying out a fault operating mode.

One example discloses a switched mode power supply device, comprising: an energy storage device; a controller configured to discharge the energy storage device; a voltage drop device having a first pin coupled to the energy storage device, a second pin coupled to the controller, and a third pin coupled to receive a first power-down signal; wherein the first power-down signal indicates that the energy storage device is to be discharged; wherein the voltage drop device is configured to input a first voltage from the energy storage device on the first pin and output a second voltage to the controller on the second pin; and wherein the second voltage is lower than the first voltage.

A discharge circuit for an X capacitor has a first voltage detection circuit providing a first indicating signal based on a voltage across two input terminals of a switching converter to indicate whether the two input terminals are connected to an AC power source, and a discharge module starting a discharge operation on the X capacitor based on first indicating signal, and the discharge operation discharges the X capacitor during a first time period, and stops discharging the X capacitor and compares a sampled signal with the voltage across the two input terminals during a following second time period.

The invention relates to a method and to a device for operating a bidirectional voltage transformer connectable to a primary battery and having a primary-side smoothing capacitor, an inductive transformer, and a secondary-side clamping capacitor, wherein, before the primary battery is connected, a voltage at the primary-side smoothing capacitor is matched to a voltage of the primary battery by a cyclical transfer of charge from the secondary-side clamping capacitor. The voltage of the primary-side smoothing capacitor is matchable in this way to the voltage of the primary battery before the primary battery is connected, and current spikes thus avoided during connection of the primary battery.

A power conversion apparatus includes a filter capacitor to be charged with electric power fed from a main power source, and a power converter to convert electric power fed via the filter capacitor and feed the converted electric power to a load. The power conversion apparatus further includes a power-source contactor to electrically connect the filter capacitor and the power converter to the main power source or electrically disconnect the filter capacitor and the power converter from the main power source, and a discharging circuit connected in parallel to the filter capacitor. The power conversion apparatus also includes a discharge control circuit to close a discharging contactor included in the discharging circuit after opening of the power-source contactor, and thereby cause the filter capacitor to be discharged.

There is described a method of controlling an inverter supplying power to a permanent magnet AC, PMAC, motor having a plurality of phase windings, The method comprises: selecting a first phase winding of the PMAC motor; electrically connecting the first phase winding to a first DC terminal of a DC link circuit at a first time, and maintaining the connection between the first phase winding and the first DC terminal: determining a flux difference between the first phase winding and a second phase winding of the PMAC motor; selecting a second time to electrically connect the second phase winding to the first DC terminal; electrically connecting the second phase winding to the first DC terminal at the second time; and maintaining the connection between the second phase winding and the first DC terminal. The second time is selected based on the determined flux difference.

A power supply device includes a power supply circuit configured to output different voltages to a plurality of output lines, a plurality of capacitors provided in correspondence with the plurality of output lines, one end of each of the plurality of capacitors being coupled to a corresponding output line of the plurality of output lines and an other end thereof being coupled to a ground potential, a plurality of diodes provided in correspondence with the plurality of output lines, anodes of the plurality of diodes being coupled to the corresponding output lines and cathodes thereof being commonly coupled, and a discharge resistor coupled to the cathodes of the plurality of diodes.

The present subject matter refers a discharge circuit for a smoothing capacitor within a power-distribution-unit. The discharge circuit comprises a first sub-circuit connected in parallel to a DC-Link capacitor, said first sub-circuit in turn comprises a series connection of a first switching element (SE) and a first discharge resistor, wherein the DC-link capacitor is connected in parallel to a power supply. A second sub-circuit is connected in parallel to the DC-Link capacitor and comprises a series connection of a second switching element (SE) and a second discharge resistor. A control device is configured to control the plurality of SEs within the sub-circuits by scheduling switching of the plurality of SEs. Such scheduling comprises switching ON of the second SE after a switching ON of the first SE for enabling a discharging of the DC link capacitor within a predetermined duration.