Electrical converter

Abstract

Electrical converter (10) for conversion between a three-phase AC signal and a DC signal, comprising: three phase terminals (A, B, C), a first and second DC terminal (P, N), a conversion circuitry (11) for conversion between three phase voltages of the three-phase AC signal and a first and second intermediate voltage at a first and second intermediate node (x, y), a first buck circuit, and a second buck circuit, wherein the first buck circuit comprises three first devices (1pa, 1pb, 1pc) that are actively switchable for connecting at least one first switch-node terminal (p; pa, pb, pc) to any one of the three phase terminals, and the second buck circuit comprises three further first devices (1na, 1nb, 1nc) that are actively switchable for connecting at least one second switch-node terminal (n; na, nb, nc) to any one of the three phase terminals. The first buck circuit comprises at least one second switching device (2p; 2pa, 2pb, 2pc) connected between the first intermediate node (x) and the at least one first switch-node terminal (p; pa, pb, pc), and at least one first filter inductor (Lp; Lpa, Lpb, Lpc) connected between the at least one first switch-node terminal (p; pa, pb, pc) and the first DC terminal (P). The second buck circuit comprises at least one further second switching device (2n; 2na, 2nb, 2nc) connected between the second intermediate node (y) and the at least one second switch-node terminal (n; na, nb, nc), and at least one second filter inductor (Ln; Lna, Lnb, Lnc) connected between the at least one second switch-node terminal (n; na, nb, nc) and the second DC terminal (N).

Description

technical field [0001] The present invention relates to the field of power conversion. In particular, the invention relates to an electrical converter and a method for converting electrical power. Background technique [0002] For example, when the battery of an electric vehicle is charging, AC voltage from the grid is converted by an electrical converter into a DC voltage, which is then supplied to the battery being charged. For example, an electrical converter may convert a three-phase AC voltage to a DC voltage between terminals of a DC bus to which a vehicle's high voltage (eg, 200V to 400V) battery may be connected. Also, wireless charging systems for electric vehicles, electric motor drives, or gradient amplifiers for magnetic resonance imaging (MRI) scanners often require this three-phase AC-to-DC conversion to create a high-voltage DC bus from which power can be drawn. . [0003] Typically, for example when a load draws power from the DC output of an electrical co...

AI Technical Summary

Problems solved by technology

[0006] Such as ‘[Reference Document 1]’ figure 1 A disadvantage of the single-stage step-down PFC converter based on the 3rd-order harmonic active filter principle proposed in , is that it requires a common-mode (L-C) output filter that typically includes a coupled capacitive midpoint to reduce the load and In a practical implementation of leakage currents to protective earth (PE), quasi-lossless zero-voltage switching (ZVS) of semiconductor switches cannot be implemented without increasing the cost, size, and complexity of the inductors of these two DC-DC step-down circuits. case (e.g. due to the need for magnetic coupling of these inductors)

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