In a device for operating a rectifier, in particular a semi-controlled rectifier bridge, and a method for operating a rectifier, in particular a power converter, the rectifier is supplied from system phases, in particular from a three-phase AC voltage system, and supplies a unipolar voltage on the output side, the rectifier including controllable switches, in particular semiconductor switches such as thyristors, etc., a respective system phase supplying a respective current source, the current generated in each case being used as trigger signal for the controllable switch allocated to the respective system phase as a function of the state of a controllable switch unit.

A power supply apparatus for providing electrical power to a power consuming device or a power conversion device from at least one of a first AC power source and a second AC power source. The power supply apparatus comprises controllable rectifier devices associated with each of the first and second AC power sources. The controllable rectifier devices are controllable to simultaneously rectify and control the power provided by the first and second AC power sources.

A method of commutation in a matrix rectifier from an active vector to a zero vector includes two steps. A method of commutation in a matrix rectifier from a zero vector to an active vector includes three steps.

An AC-DC conversion device that includes a major circuit portion and a control circuit is provided. The major circuit portion includes a converter in which multiple switch portions in a bridge connection include separately-excited switching elements and snubber circuits connected in parallel with the switching elements; and the major circuit portion is connected to an alternating current power supply and a direct current circuit and applies, to the direct current circuit, an alternating current voltage applied from the alternating current power supply by an ON of the multiple switch portions. The control circuit controls the voltage applied to the direct current circuit by controlling the ON timing of the multiple switch portions by inputting a control pulse to each of the multiple switch portions.

A method for detecting an error in a generator unit which has an electric machine (100) with a rotor winding (110) and a stator winding (120) and a rectifier (130) connected thereto, via which rectifier the electric machine (100) is connected to an electrical system (150) of a motor vehicle, the excitation current (IE) flowing through the rotor winding (110) of the electric machine (100) being plotted and it being concluded that there is an error in the generator unit depending on whether a frequency component (A) of a frequency spectrum of the plot of the excitation current (IE) in a frequency range above a lower speed limit (SW) is larger than a threshold value (S).

Since a power converter including a modular multilevel converter uses a large number of cells each combining a plurality of switching elements and a DC capacitor, there is a problem of conduction loss due to the switching elements. The conduction loss is reduced by connecting a bypass circuit between terminals of each of the cells, controlling to open and close the switching element, and controlling to short-circuit the bypass circuit connected to the cell controlled to output zero voltage.

A power supply circuit for supplying a load, which may be a SMA component or a piezoelectric component, may use short high-voltage pulses to achieve fast heating of the load and, in order to comply with functional requirements, the SMA or piezoelectric component should not be supplied by connecting it directly to an electric line at a relatively high voltage. It is also disclosed an actuator comprising a power supply circuit of this disclosure and at least one load, comprising at least one smart materials chosen between a piezoelectric device and a a shape memory alloy (SMA) component, and a method of supplying a load comprising the steps of: connecting the AC to DC voltage converter of the power supply circuit to the AC mains by closing the input switch for charging a tank capacitor of the converter and, at the same time, opening the output switch for disconnecting the load from the tank capacitor: disconnecting the AC to DC voltage converter of the power supply circuit from the AC mains by opening the input switch and, at the same time, closing the output switch to supply the load by discharging the tank capacitor.

A method of commutation in a matrix rectifier from an active vector to a zero vector includes two steps. A method of commutation in a matrix rectifier from a zero vector to an active vector includes three steps.

A high-frequency isolation alternating/direct current conversion circuit and a control method thereof are disclosed. The conversion circuit includes an alternating current source, a direct current source, a resonant capacitor, a high-voltage energy-storage filter, a high-frequency inverter bridge, a drive circuit, a resonant inductor, a high-frequency isolation transformer, a direct current side synchronous switch, a control circuit, and the like. The conversion circuit is made to be switched between two working modes, a rectification mode and an inversion mode by using a preset direct current source reference voltage as a reference, according to an external voltage reference, and by using different turn-on working modes of the high-frequency inverter bridge.

An AC/DC converter includes: a first terminal and a second terminal for receiving an AC voltage and a third terminal and a fourth terminal for supplying a DC voltage. A rectifying bridge includes input terminals respectively coupled to the first terminal and the second terminal, and output terminals respectively coupled to the third terminal and fourth terminal. A first branch of the rectifying bridge includes, connected between the output terminals, two series-connected thyristors with a junction point of the two thyristors being connected to a first one of the input terminals. A second branch of the rectifying bridge is formed by series connected diodes. A control circuit is configured to generate control signals for application to the control gates of the thyristors.