An electrical converter may include AC terminals, a first and second DC terminal, and converter modules. Each of the converter modules has an AC node. The second DC terminal forms a common node of the converter modules. A connection between the AC nodes of the converter modules and the AC terminals is reconfigurable allowing the electrical converter to operate according to a first mode of operation converting between a first AC signal having a first plurality of phase voltages and the DC signal, in which the converter modules are grouped in first groups, and according to a second mode of operation converting between a second AC signal having a single-phase voltage and the DC signal, in which the converter modules are rearranged in second groups. The electrical converter is configured to operate multiple converter modules assigned to a same group of the first groups and the second groups in parallel.

A three-phase power supply conversion circuit includes rectifier, energy storage, direct-current load, and control modules. The rectifier module includes a three-phase rectifier bridge including three bridge arms connected in parallel to each other, and a bidirectional switch assembly including three bidirectional switches. One ends of the three bidirectional switches are connected to midpoints of the three bridge arms, respectively. The energy storage module is connected to a direct-current output end of the rectifier module and includes first and second capacitors connected in series to each other. Other ends of the three bidirectional switches are connected between the first and second capacitors. The control module is connected to the bidirectional switch assembly and configured to control the bidirectional switches according to phase voltages of a three-phase alternating-current power supply, to maintain a voltage between two ends of the first or second capacitor at a target voltage.

A converter including a first terminal and a second terminal, the first terminal configured for connection to a first network, the second terminal configured for connection to a second network; at least one switching module arranged to interconnect the first terminal and the second terminal, the switching module including at least one module switching element and at least one energy storage device, the module switching element and the energy storage device arranged to be combinable to selectively provide a voltage source, the switching module switchable to control a transfer of power between the first and second networks; the switching module including a discharge circuit, the discharge circuit including a discharge switching element and a discharge resistor, the discharge switching element switchable to switch the corresponding discharge resistor into and out of the corresponding switching module; and a controller configured to selectively control the switching of the discharge switching element.

An electrical converter may include (i) m=3 phase input terminals, a neutral terminal and two output terminals, (ii) a first power stage comprising a bridge rectifier connected to each of the m phase input terminals and an output connected to an upper intermediate node and a lower intermediate node, (iii) a second power stage comprising an upper boost stage connected between the upper intermediate node and a common node, and a lower boost stage connected between the common node and the lower intermediate node, and (iv) a controller configured to operate according to a first mode of operation for converting the multi-phase AC input to the DC output or vice versa and according to a second mode of operation for converting a single phase AC input applied to at least one of the m phase input terminals and the neutral terminal to the DC output.

A transformerless parallel active rectifier system includes N multiphase common mode inductors directly connected to a shared multiphase AC input with no intervening transformer, and N active rectifiers coupled to respective ones of the N multiphase common mode inductors and having respective DC outputs coupled to a shared DC bus, where N is an integer greater than 1. The N active rectifiers have ground current regulators and are synchronized to provide DPWM switching control signals synchronized to one another to regulate their respective ground currents and concurrently regulate the shared DC bus voltage.

A phase sequence adjustment system includes a power conversion circuit and a control circuit. The power conversion circuit is connected to a main power supply with a phase sequence. The control circuit respectively provides a first and a second excitation signals to the power conversion circuit, so as to short the power conversion circuit with the main power supply twice. The control circuit includes a current detection circuit and a control unit. The current detection circuit obtains two current signals respectively during two short-circuit operations. The control unit calculates two current phase angles respectively according to these two current signals and determines whether the phase sequence is positive or negative accordingly. The control unit selects one from the two current phase angles, calculates a voltage phase angle of the main power and a phase angle difference there-between to adjust a feedback phase sequence accordingly.

The present invention generally relates to a modular high power bi-directional half bridge buck/boost converter assembly and, in particular, to a system for converting power from one form of current (either AC or DC) to a differing level of voltage, either lower (buck) or higher (boost), to output a wave signal based on pulse wave modulation (PWM) switching control by means of an external digital controller and methods of operation. In particular, an inverter-converter system includes at least one half bridge module including a plurality of circuit components, at least one inductor which is connected to the at least one half bridge module and a power supply, and a controller which is configured to receive and send instructions to the at least one half bridge module for converting an input voltage to an output voltage and dynamically tune switching frequencies based on a load of the inverter-converter system.

The invention provides a power converter apparatus for converting an alternating current (AC) power input to a direct current (DC) power output. The apparatus comprises a plurality of n single-phase power converting circuits arranged in parallel, where n is equal to or greater than 2, wherein one of said n single-phase power converting circuits comprises a single-stage AC/DC converter module having an operating AC/DC converter; and each of a remaining n−1 of said single-phase power converting circuits comprises a two-stage converter module having an AC/DC converter as an input stage and a DC/DC transformer as an output stage.

A single-phase and three-phase compatible AC-DC conversion circuit includes a first switching component, a second switching component, a third switching component, three switch bridge arms, a fourth switching component, a pre-charge resistor, a capacitor assembly, and a control unit. Each switch bridge arm has an upper switch and a lower switch connected in series. The fourth switching component is coupled between a first phase of a three-phase power source and a common-connected node of the switch bridge arm corresponding to a second phase of the three-phase power source. The control unit turns on the fourth switching component, turns on the upper switch coupled to the first switching component, and turns on the lower switch coupled to the fourth switching component to provide a discharge path so that the capacitor assembly discharges through the pre-charge resistor on the discharge path.

A bidirectional AC power converter, having a front-end comprising parallel sets of three switches in series, which connects multi-phase AC to coupling transformer through a first set of tank circuits, for synchronously bidirectionally converting electrical power between the multi-phase AC and a DC potential, and for converting electrical power between the DC potential to a bipolar electrical signal at a switching frequency, controlled such that two of each parallel set of three switches in series are soft-switched and the other switch is semi-soft switched; the coupling transformer being configured to pass the bipolar electrical power at the switching frequency through a second set of the tank circuits to a synchronous converter, which in turn transfers the electrical power to a secondary system at a frequency different from the switching frequency.