METHOD OF OPERATING A MULTI-PHASE DC-DC CONVERTER

Abstract

A method for balancing in a multi-phase DC-DC converter, wherein at least two cells are provided, in each of which at least two phases of the DC-DC converter are grouped, wherein an operation of the individual cells is correlated with respective cell operating values, and an operation of the individual phases is correlated with respective phase operating values, and for balancing, an at least two-stage regulation is carried out with the steps: modulating the phase operating values of the phases as per a first regulation so that the phase operating values are modulated within the cell, and/or modulating the cell operating values of the cells as per a second regulation such that the cell operating values are modulated among themselves.

Claims

1. A method for balancing in a multi-phase DC-DC converter, wherein at least two cells are provided, in each of which at least two phases of the DC-DC converter are grouped, wherein in each cell of the two cells, a cell operating value of the respective cell is correlated with an operation of this cell and in each phase, a phase operating value of the respective phase is correlated with an operation of this phase, and for balancing an at least two-stage regulation the method comprises: modulating the phase operating values of the phases in accordance with a first regulation so that the phase operating values are modulated within the cell; and modulating the cell operating values of the cells per a second regulation so that the cell operating values are modulated among themselves.

2. The method according to claim 1, wherein via the second regulation, the modulation of the cell operating values of the cells among themselves is regulated in that a common set value for at least two or all cell operating values is determined, and wherein a primary phase modulation takes place.

3. The method according to claim 1, wherein, for the first regulation, for at least one of the cells or for each cell, a respective cell-specific set value for the phase operating values of the phases of this cell is determined, and wherein the intracellular modulation of the phase operating values takes place.

4. The method according to claim 1, wherein, for the first regulation, the phase operating values of the phases of a respective cell are modulated to a respective cell-specific set value, wherein the set value is determined based on the phases of the respective cell or based on a reference phase of the respective cell.

5. The method according to claim 1, wherein, as per the first regulation, the phase operating values of the phases of at least a first cell are modulated to a first cell-specific set value, and the phase operating values of the phases of at least a second cell are modulated to a second cell-specific set value, which differs from the first cell-specific set value, and wherein, as per the second regulation for the at least first cell and the second cell, the respective cell operating values are modulated to a common set value that is determined on based on a load of the DC-DC converter.

6. The method according to claim 1, wherein the phase operating values and cell operating values are each specific to an electrical output variable or a current or voltage or power so that the electrical output variable of a respective cell is correlated with the electrical output variables of the phases of this cell, and wherein an electrical output variable of the DC-DC converter is correlated with the electrical output variables of the cells.

7. The method according to claim 1, wherein the modulation of the phase operating values occurs in that the timing of the phases is regulated in a phase-specific manner, wherein the modulation of the cell operating values occurs in that a timing of the cells is regulated in a cell-specific manner, and wherein the timing is performed via at least one pulse width modulation unit of at least one processing device.

8. The method according to claim 1, wherein the respective modulation is made in each case by a PID controller which is provided by a processing device.

9. The method according to claim 1, wherein a current measurement and/or power measurement at the individual phases is performed by a processing device for purposes of regulation.

10. The method according to claim 1, wherein, in the cells, in each case at least three or exactly three phases of the DC-DC converter are grouped.

11. A DC-DC converter for a power transfer between two power supplies, which is designed multi-phase, the converter comprising: at least four phases; and at least two cells, wherein in the two cells, at least two of the phases of the DC-DC converter are grouped so that the power transfer is divided among the cells and individually supplied.

12. The DC-DC converter according to claim 11, wherein the DC-DC converter has at least or exactly six phases, wherein, in each of the cells, at least or exactly three of the phases of the DC-DC converter are grouped.

13. The DC-DC converter according to claim 11, wherein the power transfer in a normal operation of the DC-DC converter is supplied by all of the cells, and, in an error mode of the DC-DC converter, are supplied by least one of the cells, and wherein, in the error mode, at least one of the cells is defective.

14. The DC-DC converter according to claim 11, wherein the phases are grouped uniformly in the cells and/or in such that in an error mode of the DC-DC converter, the power transfer are supplied at substantially 50%.

15. The DC-DC converter according to claim 11, wherein the DC-DC converter is a 48 V/12 V DC-DC converter so that via the power transfer, a voltage of a 48 V network is converted into a voltage of a 12 V network, and/or vice versa.

16. The DC-DC converter according to claim 11, wherein the phases are each designed in a half-bridge topology.

17. The DC-DC converter according to claim 11, wherein the cells are power cells or a multi-phase power stage, so that independently of one another, the power transfer for the DC-DC converter is supplied by the cells.

18. The DC-DC converter according to claim 11, further comprising a processing device configured for implementing the method according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0053] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:

[0054] FIG. 1 a schematic representation for visualizing an inventive method and a DC-DC converter according to the invention,

[0055] FIG. 2 a further schematic representation for visualizing a method according to the invention,

[0056] FIG. 3 a further schematic representation for visualizing a method according to the invention and a DC-DC converter according to the invention,

[0057] FIG. 4 a schematic representation for visualizing sections of a DC-DC converter according to the invention.

DETAILED DESCRIPTION

[0058] FIG. 1 schematically shows an inventive DC-DC converter 10, which comprises several phases 20. The phases 20 are grouped in cells 30, wherein each of the cells 30 comprises in each case at least two phases 20. Accordingly, a first cell 31 and a second cell 32 are shown, which each comprise a first phase 21 and a second phase 22. A modulation of a cell operating value 430 thereby directly (immediately) influences the single cell 30, and thus indirectly also the phases 20, which are grouped into this cell 30. A modulation of a phase operating value 420, however, affects the individual phases 20 in a direct manner.

[0059] Schematically, the cell operating values 430 and the phase operating values 420 are shown in FIG. 2. Furthermore, it is shown that the cell operating values 430 are modulated by a second regulation 120 and that the phase operating values 420 are modulated by a first regulation 110. The modulation is carried out, for example, by a processing device 200 shown in FIG. 1, in particular by a pulse width modulation unit 210.

[0060] In FIG. 3, an inventive DC-DC converter 10 with (at least) two cells 30 is schematically shown. Each of the cells 30 in this case comprises (at least) three phases 20. In this case, it may be provided that a first phase 21 and second phase 22 and a third phase 23 of the first cell 31 differ from a first phase 21 and a second phase 22 and a third phase 23 of a second cell 32.

[0061] In FIG. 4, a first cell 31 and a second cell 32 are schematically shown, each comprising three phases 21, 22, 23 of the DC-DC converter. Each of the phases 20 can function independently of the other phases 20 for the power transfer and therefore comprises in each case at least one electronic component, for example, a resistor or a transistor element, independent of the other phases 20. It is shown schematically that the electronic component 24 or the respective phase 20 may be designed as a bridge topology, in particular a half-bridge topology. For example, the configuration of the individual phases 20 is configured such that the phases 20 of a first cell 30 can be operated for the power transfer independently of the phases 20 of a second cell 32. This makes it possible in a particularly advantageous manner that due to the respective phases 20, the cells 30 can be used independently of each other for purposes of the power transfer.

[0062] The foregoing explanation of the embodiments describes the present invention only in the context of examples. Of course, individual features of the embodiments can be freely combined with each other without departing from the scope of the present invention, provided this is technically useful.

[0063] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.