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CN-121986442-A - Circuit arrangement for generating a DC output voltage and use of the circuit arrangement for testing an electrical energy store

CN121986442ACN 121986442 ACN121986442 ACN 121986442ACN-121986442-A

Abstract

The invention relates to a circuit arrangement (1) for generating at least one DC output voltage (2, 2a,2 b) on the basis of an AC input voltage (3), having at least one input stage (4), at least one current transformer (5) and at least one DC voltage converter (10, 10a,10 b), wherein the input stage (4) can be connected to the AC input voltage (3) and an intermediate circuit voltage can be generated using the input stage (4), and wherein at least one first DC voltage (6 a,6 b) and at least one second DC voltage (7 a,7 b) can be generated from the intermediate circuit voltage using the current transformer (5), wherein the current transformer (5) has at least one double resonant stage (8, 8a,8 b) for generating the first DC voltage (6 a,6 b) and the second DC voltage (7 a,7 b), and wherein the DC voltage converter (10, 10a,10 b) can generate the DC voltage (6 a,6 b) from the first DC voltage (6 a,6 b) and the second DC voltage (7 a,7 b). The circuit arrangement (1) is improved in that the first DC voltage (6 a,6 b) and the second DC voltage (7 a,7 b) are conducted to a common ground, and that a first output of the DC voltage converter (10, 10a,10 b) is placed against the common ground of the first DC voltage (6 a,6 b) and the second DC voltage (7 a,7 b).

Inventors

  • W. MILLER

Assignees

  • EA泰克自动化有限公司

Dates

Publication Date
20260505
Application Date
20240628
Priority Date
20230628

Claims (17)

  1. 1. A circuit arrangement (1) for generating at least one DC output voltage (2, 2a,2 b) on the basis of an AC input voltage (3), having at least one input stage (4), at least one current transformer (5) and at least one DC voltage converter (10, 10a,10 b), wherein the input stage (4) can be connected to the AC input voltage (3) and an intermediate circuit voltage can be generated using the input stage (4), and wherein at least one first DC voltage (6 a,6 b) and at least one second DC voltage (7 a,7 b) can be generated from the intermediate circuit voltage using the current transformer (5), Wherein the converter (5) has at least one double resonant stage (8, 8a,8 b) for generating the first DC voltage (6 a,6 b) and the second DC voltage (7 a,7 b), And wherein the DC output voltage (2, 2a,2 b) can be generated from the first DC voltage (6 a,6 b) and the second DC voltage (7 a,7 b) by means of the DC voltage converter (10, 10a,10 b), It is characterized in that the method comprises the steps of, The first direct voltage (6 a,6 b) and the second direct voltage (7 a,7 b) are directed to a common ground point, and The first output of the dc voltage converter (10, 10a,10 b) rests on a common ground of the first dc voltage (6 a,6 b) and the second dc voltage (7 a,7 b), and the second output of the dc voltage converter (10, 10a,10 b) is connected to the converter (5) such that the dc output voltage (2, 2a,2 b) can be generated as a controllable dc output voltage (2, 2a,2 b) having an arbitrary sign.
  2. 2. Circuit arrangement (1) according to claim 1, characterized in that the converter (5) is configured as a direct voltage converter or rectifier, in particular as an LLC resonant converter.
  3. 3. The circuit arrangement (1) according to any of the preceding claims, characterized in that the dual resonant stages (8, 8a,8 b) each have a first LLC stage (9 a) and a second LLC stage (9 b) connected in parallel to the first LLC stage.
  4. 4. A circuit arrangement (1) according to claim 3, characterized in that the first LLC stage (9 a) has a first capacitor (C1), a first inductance (L1) and a first transformer (T1, T3), and the second LLC stage (9 b) has a second capacitor (C2), a second inductance (L2) and a second transformer (T2, T4).
  5. 5. Circuit arrangement (1) according to claim 4, characterized in that the converter (5), in particular an LLC converter, has at least one front-end H-bridge fed with the intermediate circuit voltage and the at least one dual resonant stage (8, 8a,8 b), wherein the ac side of the H-bridge is connected to the primary side of the first transformer (T1, T3) via a first capacitor (C1) and a first inductance (L1) of the series connection of the first LLC stage (9 a) and to the primary side of the second transformer (T2, T4) via a second capacitor (C2) and a second inductance (L2) of the series connection of the second LLC stage (9 b).
  6. 6. Circuit arrangement (1) according to claim 4, characterized in that the converter (5), in particular the LLC converter, has at least one front-end H-bridge fed with the intermediate circuit voltage and connected to a first and a second transformer (T1, T2), wherein a first capacitor (C1) and a first inductance (L1) of the series connection of the first LLC stage (9 a) are arranged on the secondary side of the first transformer (T1), and a second capacitor (C2) and a second inductance (L2) of the series connection of the second LLC stage (9 b) are arranged on the secondary side of the second transformer (T2).
  7. 7. The circuit arrangement (1) according to claim 5 or 6, characterized in that the secondary side of the first transformer (T1, T3) and the secondary side of the second transformer (T2, T4) are connected such that the first dc voltage (6 a,6 b) can be generated with the first LLC stage (9 a) and the second dc voltage (7 a,7 b) can be generated with the second LLC stage (9 b).
  8. 8. The circuit arrangement (1) according to claim 7, characterized in that the secondary side of the first transformer (T1) and the secondary side of the second transformer (T2) each have a full-bridge rectifier circuit, preferably each have four transistors (Q1-Q4), or the first transformer (T3) and/or the second transformer (T4) have multiple windings, preferably multiple windings connected in series, in particular double windings, on the secondary side, and the secondary side of the first transformer (T3) and the secondary side of the second transformer (T4) each have a half-bridge rectifier circuit.
  9. 9. A circuit arrangement (1) as claimed in claim 3, characterized in that the converter (5) has a transformer (T5) with multiple windings, in particular double windings, connected in series on the secondary side, and at least one front-end H-bridge fed with the intermediate circuit voltage and connected to the transformer (T5), wherein the first LLC stage (9 a) has a first capacitor (C1) and a first inductance (L1) connected in series coupled to a first secondary winding of the transformer (T5), and the second LLC stage (9 b) has a second capacitor (C2) and a second inductance (L2) connected in series coupled to a second secondary winding of the transformer (T5), wherein preferably the two secondary windings are connected such that the first dc voltage (6 a) can be generated with the first LLC stage (9 a) and the second dc voltage (7 a) can be generated with the second LLC stage (9 b).
  10. 10. The circuit arrangement (1) according to any of the preceding claims, characterized in that the dc output voltage (2, 2a,2 b) is changeable between the value of the positive first dc voltage (6 a,6 b) and the value of the negative second dc voltage (7 a,7 b).
  11. 11. The circuit arrangement (1) as claimed in claim 10, characterized in that the dc voltage converter (10, 10a,10 b) is configured as a buck-boost stage (11) or as a linearly regulated output stage or buck stage, wherein preferably each dual resonant stage (8, 8a,8 b) has a buck-boost stage (11) or a linearly regulated output stage or buck stage.
  12. 12. The circuit arrangement (1) according to claim 11, characterized in that the buck-boost stage (11) is connected to the first direct voltage (6 a,6 b) via a first switching element (Q7), in particular a transistor, and to the second direct voltage (7 a,7 b) via a second switching element (Q8), in particular a transistor, and in that the direct output voltage (2, 2a,2 b) is provided via at least one capacitor (C3) connected in series with at least one energy storage choke (L3), wherein preferably the energy storage choke (L3) is connected in series with a current measuring shunt (R1).
  13. 13. Circuit arrangement (1) according to any one of the preceding claims, characterized in that at least two dual resonant stages (8, 8a,8 b), preferably 3 to 64 dual resonant stages (8, 8a,8 b), in particular 6 dual resonant stages (8, 8a,8 b), are provided.
  14. 14. Circuit arrangement (1) according to any of the preceding claims, characterized in that the first and second direct voltages (6 a,6b,7a,7 b) are below 100V, in particular below 50V, preferably below 20V, particularly preferably in the range of 10V to 20V, and/or the alternating input voltage is between 100V and 690V.
  15. 15. The circuit arrangement (1) according to any one of the preceding claims, characterized in that the input stage (4) is constructed and arranged such that an intermediate circuit voltage of 300V to 1200V, preferably 800V, can be produced, wherein preferably the input stage (4) is constructed as a power factor controller.
  16. 16. Use of a circuit arrangement (1) according to any of the preceding claims for testing at least one electrical energy store.
  17. 17. The use according to claim 16, wherein the energy store has at least one primary cell, at least one secondary cell, at least one single cell, at least one half cell or at least one supercapacitor.

Description

Circuit arrangement for generating a DC output voltage and use of the circuit arrangement for testing an electrical energy store Technical Field The invention relates to a circuit arrangement for generating at least one DC output voltage on the basis of an AC input voltage. The circuit arrangement has at least one input stage, at least one current transformer and at least one DC voltage converter. The input stage may be connected to an alternating input voltage and with which at least one intermediate circuit voltage may be generated. With the converter, at least one first direct voltage and at least one second direct voltage can be generated from the intermediate circuit voltage. The converter has at least one dual resonant stage for generating a first DC voltage and a second DC voltage. The dc output voltage may be generated from the first dc voltage and the second dc voltage using a dc voltage converter. The invention further relates to the use of the circuit arrangement for testing an electrical energy store. Background Electronic circuits and components typically operate using direct current voltages. In most cases, a plurality of different potentials are required simultaneously. In order to be able to supply power from an ac power system, the supplied ac voltage (ac input voltage) must first be converted into a corresponding dc output voltage by means of a circuit arrangement. The known circuit arrangement generally comprises an input-side AC/DC converter which has a single, usually relatively high, DC voltage, the so-called bus voltage, at the output, from which the downstream DC/DC converter generates the DC voltage required for the individual components. The complexity of such topologies is sometimes relatively high and/or contains components that create significant disturbances at the output. Furthermore, for special applications such as testing of electrical energy stores, it is also required that negative output voltages can also be generated. For many electronic devices, including also test devices for testing electrical energy stores, legal safety requirements are also applicable, according to which galvanic isolation of the supply side from the low-voltage network from external terminals is to be provided (for example DIN EN 61010 (publication date 2020-03): sicherheitsbestimmungen f u R ELEKTRISCHE MESS-, steuer-, regel-und Laborger ä te). It is basically known to achieve galvanic isolation at an input converter (AC/DC converter) by means of an integrated or pre-transformer. But galvanic isolation may also be performed in a DC/DC converter. For this purpose, output-side DC/DC converters are mostly used, which, however, become very expensive due to the high power. Furthermore, it is known to use galvanic isolation of transformers at the grid terminals. Additional, separate transformers may also be provided on the AC side. For example, DE 10 2014 013 039 A1 discloses a device for a motor vehicle for the galvanically decoupled transmission of a voltage between a high-voltage circuit and a voltage circuit, with a galvanically isolated dc voltage converter and a galvanically coupled dc voltage converter which are connected such that the galvanically isolated dc voltage converter converts a high-voltage dc voltage supplied by the high-voltage circuit into a first dc voltage and the galvanically coupled dc voltage converter converts the first dc voltage into a second dc voltage. US 2015/375628 A1 discloses a charging device with galvanic isolation for an electric vehicle with a reversible AC/DC converter enabling to supply two outputs with different voltages with current. Charging devices with galvanic isolation for electric vehicles are also known from US 2013/162032 A1, US 2013/175990 A1 and DE 10 2017 208360 A1, in which a plurality of converters are each provided. DE 10 2012 212 291 A1 discloses a device for direct-current fast charging or discharging of an energy storage device, which has an AC/DC converter module coupled to a supply grid and a DC/DC regulator module electrically coupled to the AC/DC converter module, wherein the DC/DC regulator module has a DC/DC buck regulator module without galvanic isolation and has a DC/DC resonant converter module for galvanic isolation. As mentioned, the test device or test facility for testing the electrical energy store also operates with a direct voltage. Therefore, a circuit arrangement for generating a dc output voltage based on an ac input voltage is particularly required here. A mobile or stationary device or electrical system for storing electrical energy and releasing it again when needed is called an electrical energy store. Such energy storage devices are based on chemical or physical effects and are usually implemented in practice as batteries or capacitors. The characteristics of the electrical energy storage are determined by a test device. The test is essentially based on delivering electrical energy to the energy storage and extracting i