For a power supply with a reduced number of semiconductor devices, a phase shifting transformer receives a three-phase primary voltage and steps the three-phase primary voltage one of up and down to a secondary voltage with a plurality of secondary winding sets. There is phase shifting between different secondary winding sets. A plurality of power cell sets each comprise a plurality of power cells cascaded connected, and each power cell receives one of a single phase and a three-phase voltage of a distinct secondary winding set of the phase shifting transformer. Each power cell comprises no more than eight power semiconductor devices organized as a rectifier and an inverter. Each power semiconductor device is one of a diode and an active switch. Each power cell set generates one phase of a three-phase alternating current output.

A dual-comparator rectifier circuit of a wireless power receiver includes a receive coil configured to generate a current in response to receiving power through electromagnetic waves from a wireless power transmitter and a bridge circuit. The bridge circuit includes four branches, and one node of each of the four branches is coupled to one of a first node or a second node of the receive coil. A first branch and a second branch of the four branches are coupled to the first node and the second node of the receive coil and include a first circuit and a second circuit, respectively. The first circuit includes a first comparator and a first switch circuit and the second circuit includes a second comparator and a second switch circuit. The first circuit and the second circuit can set a dynamic turn-on threshold for the first switch circuit and the second switch circuit, respectively.

The present disclosure relates to semiconductors. Some embodiments may include a series circuit arrangement of power semiconductors comprising: cooling-water boxes arranged on the semiconductors and electrically connected to them; two cooling-water distributor lines; respective branchings on the cooling-water distributor lines for the cooling chambers; and a control electrode arranged on the cooling-water distributor lines. The cooling chambers are connected in parallel between the cooling-water distributor lines with respect to a cooling-water stream. The cooling chambers are connected to the branchings via a respective connecting line. For at least some of the cooling chambers, the branchings on the cooling-water distributor lines are arrayed relative to the position of the respective cooling chamber in offset manner in relation to a geometrically shortest possible link to the cooling-water distributor lines, so that a difference of potential between the cooling chambers and the branchings is minimized.

A thyristor bridge of an electrical converter is connected to at least one DC link and including at least one phase leg for each output phase and each phase leg being composed of two series-connected thyristor arms. The thyristor arms of a thyristor bridge are cyclically switched by: determining an upper bound for a firing angle of a thyristor arm, wherein the upper bound is determined from voltage and current measurements; and determining a firing angle for the thyristor bridge, which firing angle determines a switching time of the thyristor arm, wherein the firing angle is determined, such that it is less or equal to the upper bound.

A method and system for controlling a three-phase drive connected to a three phase power source. The method includes connecting a converter to transfer power from the power source to a first direct current (DC) bus, where the converter and the first DC bus each have a neutral common point (NCP). Connecting a second DC bus to the first DC bus and configuring an inverter connected to the second DC bus to draw power from the second DC bus to provide a plurality of motor signals, the inverter having an inverter NCP. The method also includes connecting a neutral point selection device to the first DC bus NCP and selectively connecting to the converter NCP or the inverter NCP, the bus selection device configured to disconnect the converter NCP or the inverter NCP from the first DC bus NCP under selected conditions.

An operating circuit and a method for operating a synchronous machine on a voltage supply network is disclosed. The operating circuit has a converter circuit with controllable converter switches and a controllable switching arrangement to switch the converter circuit between a start converter configuration and a direct converter configuration. The power supply network is connected to a converter output and the synchronous machine is connected to a converter input of the converter circuit. In the direct converter configuration, an AC voltage is provided at the converter output with a preset AC voltage frequency. In the direct converter configuration, the switching of the AC voltage between the converter input and the converter output takes place without intermediate rectification.

The present invention corresponds to a method and an apparatus for detecting faults in transmission and distribution systems. The method is characterized by the steps of: a) Rectifying the ac current signal of the auxiliary services triphasic system; b) Rectifying and inverting the ac current signal of the transmission and distribution system; c) Connecting the step b signal to step a signal; d) Measuring the ac current signal obtained in step b; e) Measuring the dc current signal rectified in step a; f) Scaling the value of the current measured in step e by a scale k factor; g) Calculating the rms value of the signal measured in step d; h) Finding the difference between the values obtained in steps f and g; i) Comparing the absolute value of the step h difference with a reference value m; j) If the comparison made in step i is greater than the reference value m, a trigger signal is generated and the tension is maintained between the dc points of step b in about from 0 to 90%, of the operating tension with no fault. The apparatus comprises, a rectifier; an inverter connected to the rectifier; current measuring means at the rectifier and inverter outlets; and a control unit connected with the rectifier, the inverter and the current measuring means that makes the tripping command of the rectifier and the inverter, and compares the dc current measure at the rectifier outlet with the inverter outlet current, sending a tripping signal according to said comparison.

An uninterruptible power supply circuit includes an inverter circuit configured to be connected to a first AC power grid, the power supply circuit moreover being configured to adopt a first configuration for supplying power to the first AC power grid from a second AC power grid, wherein first configuration a power factor correction circuit is configured to be connected to the second AC power grid so as to deliver a DC voltage to the inverter circuit, the power factor correction circuit comprising an inductor, and a first switch branch pertaining to the power factor correction circuit and the inverter circuit; and a second configuration for supplying power to the first AC power grid from a DC voltage source, wherein second configuration a DC-DC converter circuit is configured to be connected to the DC voltage source so as to deliver a DC voltage to the inverter circuit, the inductor moreover pertaining to the DC-DC converter circuit.

A vehicle charging system includes a charging station comprising a controller configured to selectively supply power from a vehicle to a home. The controller enables charging in response to a predetermined minimum voltage and a predetermined minimum current on an electric vehicle supply equipment (EVSE) side of the charging station. A mobile battery station is configured to supply power from a plurality of batteries to the EVSE side of the charging station at a first voltage greater than or equal to the predetermined minimum voltage and a first current greater than the predetermined minimum current.

An insulation design apparatus performing the insulation design of a high voltage direct current (HVDC) transmission system is provided. The insulation design apparatus includes a first insulation model generation unit; a second insulation model generation unit; an insulation verification unit, wherein the second insulation model generation unit selects the positions of each facility, device and arrester of the HVDC transmission system through a system single line diagram to select a representative facility in the HVDC transmission system, divides the HVDC transmission system into the plurality of regions based on the selected representative facility, and generates an insulation model for each region.