A power converter, includes a first terminal and a second terminal which are connected to a direct current; a third terminal connected to an alternating current; N multi-level bridge arms connected in parallel to the first terminal and the second terminal, where the N multi-level bridge arms work in a parallel-interleaved manner, each multi-level bridge arm of the N multi-level bridge arms includes an alternating current node, and multiple time-varying levels are generated at the alternating current node, where the multiple levels are more than two levels; and a coupling inductor, including N windings coupled by one common magnetic core, where one end of each winding of the N windings is connected to an alternating current node of one multi-level bridge arm of the N multi-level bridge arms, and the other end of each winding of the N windings is connected to the third terminal.

In a multilevel converter, three switches are connected between three arms and three reactors, and three resistive elements are connected to the respective three switches in parallel. The three switches are configured to be in a conductive state during a normal operation. The three switches are configured to come into a non-conductive state when a short circuit accident occurs between two DC power transmission lines, whereby an inter-arm direct current flowing in four arms and the like is quickly attenuated by the three resistive elements.

In a multilevel converter, three switches are connected between three arms and three reactors, and three resistive elements are connected to the respective three switches in parallel. The three switches are configured to be in a conductive state during a normal operation. The three switches are configured to come into a non-conductive state when a short circuit accident occurs between two DC power transmission lines, whereby an inter-arm direct current flowing in four arms and the like is quickly attenuated by the three resistive elements.

Voltage transformer (A) and rectifier (B1), (B2) meant for power supply for LED lamps wherein the mentioned transformer (A) comprises a three-phase primary winding and at least two three-phase secondary windings wherein the outputs (1u, 1 v, 1 w) and (2u, 2v, 2w) of the mentioned secondary windings are connected to the rectifiers (B1) and (B2). The secondary windings are divided for several primary windings with various phases and are connected with various connections between outputs of the secondary windings in order to create the desired phase differences or the secondary windings have each their own primary winding wherein the connections between the outputs of the secondary windings have a characteristic, desired phase difference.

A control method which is deployed in a control installation of an electric motor, the control installation including a first converter controlled for the application of the first voltage pulse edges to an electric motor of a first pulse width modulation, obtained by comparing a first carrier signal, applied at a first chopping frequency, with a first modulating signal, a second converter controlled of a second pulse width modulation, obtained by comparing a second carrier signal, applied at a second chopping frequency, with a second modulating signal. The control method involves the determination of a notional optimum phase-shift angle on the basis of the first chopping frequency and the second chopping frequency.

A system for controlling a plurality of power converters in a power system so as to turn each of the plurality of power converters into an ON state or an OFF state as a function of a sensed input power and a sensed output power such that one or more of the plurality of power converters in the ON state are operating in an optimal power efficiency range.

Methods and apparatus provide compensation for impedance changes in a network energized by an amplifier, such as a class E amplifier. In embodiments, bus voltage amplifier fundamental AC output voltage can be used to generate a feedback signal for adjusting impedance of one or more components in the network. In embodiments, the amplifier fundamental AC output voltage is determined from current to the load, wherein the load is coupled to the amplifier by an LCL impedance matching network.

Methods and apparatus provide compensation for impedance changes in a network energized by an amplifier, such as a class E amplifier. In embodiments, bus voltage amplifier fundamental AC output voltage can be used to generate a feedback signal for adjusting impedance of one or more components in the network. In embodiments, the amplifier fundamental AC output voltage is determined from current to the load, wherein the load is coupled to the amplifier by an LCL impedance matching network.

A power conversion device achieves size reduction and reliability by reducing the number of components of the system. The power conversion device has a semiconductor module of a half-bridge configuration in which two semiconductor elements are arranged in series. The semiconductor module has a cuboidal shape and has, along a longitudinal direction thereof, a positive pole terminal, a negative pole terminal, and terminals for inputting or outputting alternating current or for forming a single phase of the power conversion device. In the vertical direction corresponding to a widthwise direction of the cuboid, a plurality of the semiconductor modules are arranged vertically, forming a plurality of phases of the power conversion device. The semiconductor modules of the plurality of phases are installed in contact with a cooling unit, and one or more capacitors are disposed so as to face the cooling unit across the semiconductor modules of the plurality of phases.

An integrated communication power system supplies power to a communication equipment, and the communication equipment includes a base station module and an antenna processing module. The integrated communication power system includes a first transfer switch, a first integrated conversion module, a DC conversion module, and an energy storage module. The first transfer switch selectively switches one of input sources and a renewable energy to be coupled to the first integrated conversion module to receive an input voltage. The first integrated conversion module converts the input voltage into a DC voltage, and the DC conversion module provides an output voltage to supply power to the antenna processing module according to the DC voltage. The energy storage module receives an energy storage voltage provided by the first integrated conversion module or the DC conversion module to supply power to the base station module.