CN107294397B - Device and method for converting an alternating current - Google Patents
Device and method for converting an alternating current Download PDFInfo
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- CN107294397B CN107294397B CN201710232241.2A CN201710232241A CN107294397B CN 107294397 B CN107294397 B CN 107294397B CN 201710232241 A CN201710232241 A CN 201710232241A CN 107294397 B CN107294397 B CN 107294397B
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- 238000000034 method Methods 0.000 title claims abstract description 20
- 238000004590 computer program Methods 0.000 claims abstract description 5
- 230000006978 adaptation Effects 0.000 claims description 2
- 238000003466 welding Methods 0.000 description 10
- 238000010586 diagram Methods 0.000 description 6
- 230000006378 damage Effects 0.000 description 5
- 230000007257 malfunction Effects 0.000 description 4
- 230000006870 function Effects 0.000 description 3
- 230000015654 memory Effects 0.000 description 2
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/40—Testing power supplies
- G01R31/42—AC power supplies
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M5/00—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases
- H02M5/02—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc
- H02M5/04—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters
- H02M5/10—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using transformers
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/32—Means for protecting converters other than automatic disconnection
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/285—Single converters with a plurality of output stages connected in parallel
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M5/00—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases
- H02M5/02—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc
- H02M5/04—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters
- H02M5/10—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using transformers
- H02M5/12—Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using transformers for conversion of voltage or current amplitude only
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
- G01R31/62—Testing of transformers
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/0003—Details of control, feedback or regulation circuits
- H02M1/0009—Devices or circuits for detecting current in a converter
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/32—Means for protecting converters other than automatic disconnection
- H02M1/325—Means for protecting converters other than automatic disconnection with means for allowing continuous operation despite a fault, i.e. fault tolerant converters
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/33538—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only of the forward type
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Abstract
The invention relates to a device and a method for converting an alternating current. The invention relates to a device for converting an input alternating current, the device comprising: a first transformer (4 a) which is set up to convert a first part of the input alternating current into a first output alternating current; a second transformer (4 b) which is designed to convert a second part of the input alternating current into a second output alternating current, wherein the second transformer is connected in parallel with the first transformer on the input side; a comparator (6) which is set up to compare a quantity characterizing the first output alternating current with a quantity characterizing the second output alternating current and to determine a comparison value on the basis thereof; and a signal unit (10) which is set up to output a signal on the basis of the comparison value. The invention also relates to a method for converting an input alternating current and to a computer program for carrying out the method.
Description
Technical Field
The present invention relates to a device and a method for converting an alternating current, as well as to a computing device and a computer program for carrying out the method according to the invention.
Background
In many cases, for providing an alternating voltage or an alternating current or for converting an alternating voltage and/or an alternating current, it is often possible to use a combination of a plurality of transformers which are connected in parallel in a switching circuit. This can be used, for example, to feed the welding points with a welding current via a plurality of parallel branches, each of which may have, for example, its own transformer.
In this case, if, for example, damage or interference occurs in the respective branch, in some cases, a restricted operation of one of the parallel branches or even a malfunction of one of the parallel branches may occur. This may result, in particular, in the case of the parallel branch or transformer being supplied with alternating voltage and alternating current by an inverter: the remaining ones of the parallel branches that are not directly damaged or disturbed continue to operate without assistance from the disturbed or damaged branch. In this case, the failure of one of the parallel branches may lead to a significant increase in the load in the remaining branches and, in the worst case, to a failure of the other of the parallel branches.
It is therefore desirable to identify malfunctions or limited functionality in one (or more) of the parallel branches early and reliably, so that measures can be introduced to avoid further damage.
Disclosure of Invention
According to the invention, a device and a method for converting an input alternating current are proposed with the features of the independent patent claims. Advantageous embodiments are the subject matter of the dependent claims and the subsequent description.
In one aspect, the invention relates to a device for converting an input alternating current, comprising: a first transformer which is set up to convert a first part of an input alternating current into a first output alternating current; a second transformer which is set up to convert a second part of the input alternating current into a second output alternating current, wherein the second transformer is connected in parallel with the first transformer on the input side; a comparator which is set up to compare a quantity which characterizes the first output alternating current with a quantity which characterizes the second output alternating current and to determine a comparison value on the basis thereof; and a signal unit configured to output a signal based on the comparison value. Preferably, the transformers are also connected in parallel on the output side, so that the output alternating currents add up.
In this case, the first and second part of the input alternating current can be provided, for example, by a single voltage or current source, wherein, for example, the input alternating current is distributed to a first transformer and a second transformer connected in parallel. In particular, the input alternating current can be provided by means of an inverter, which in turn can have an external current or voltage source.
For example, it is also possible to form more than two parallel branches, each with one or more transformers, so that in some embodiments more than two transformers are connected in parallel on the input side and in particular also on the output side.
In a further aspect, the invention relates to a method for converting an input alternating current, wherein a first part of the input alternating current is converted into a first output alternating current by means of a first transformer and a second part of the input alternating current is converted into a second output alternating current by means of a second transformer, wherein the second transformer is connected in parallel on the input side and in particular also on the output side with the first transformer, wherein a quantity characterizing the first output alternating current and a quantity characterizing the second output alternating current are compared, wherein a comparison value is determined on the basis of the comparison of the quantity characterizing the first output alternating current and the quantity characterizing the second output alternating current, and wherein a signal is output on the basis of the determined comparison value as long as the determined comparison value is within a predetermined range.
For example, the predetermined range may be a range of values that indicates: as long as the comparison value is within the predetermined range, there is an asymmetric load or even a malfunction of one or more of the parallel branches.
The invention provides the following advantages: the parallel-connected transformers on the input side and in particular also on the output side can be monitored with regard to their operation and their function. In particular, the circuits or the wiring in which the transformer is connected can be monitored during operation, i.e. during the time in which the transformer is loaded with an input alternating current and correspondingly converts the input alternating current into a corresponding output alternating current. This provides the following particular technical advantages: during operation, for example, a restricted function or even a complete failure of one or more transformers or corresponding parallel branches can be determined, and measures can therefore be introduced in good time in order to avoid further damage in the device.
The invention provides in detail the following possibilities: monitoring the current distribution in the parallel branches or parallel transformers and thereby determining that an asymmetric current distribution occurs between the parallel branches. In particular, a parameter can be provided by comparing a variable of the transformer which characterizes the output alternating current and a subsequent determination of a comparison value, by means of which an asymmetrical current distribution can be identified. As long as the comparison value indicates an asymmetrical current distribution, the signaling unit can, for example, output a corresponding warning signal which indicates an asymmetrical load or a malfunction of the branch. Based on the alarm signal, the external control unit may, for example, introduce countermeasures in order to eliminate the asymmetric current distribution or to switch off the device.
Thus, in the presence of an asymmetrical current distribution or an asymmetrical load, a symmetrical current distribution can be achieved, for example, by targeted actuation of the inverter which supplies the input alternating current. This can be achieved, for example, in a similar manner to when controlling a Gantry shaft (Gantry-Achse), in which two separate feed motors move a common drive shaft. The two independent feed motors must be operated as synchronously as possible, for which specific control functions are known.
Preferably, the output alternating current itself, or the rectified output alternating current, or a voltage which is dropped across the measuring resistor as a result of the output alternating current or the rectified output alternating current, is used as a variable which characterizes the output alternating current. These variables can be measured very simply technically. For example, the current can be conducted to the current measuring device by means of a current converter (coil).
According to a preferred embodiment, the device according to the invention is designed to provide a welding current, in particular for resistance welding, further in particular for medium-frequency resistance welding. Due to the parallel connection of a large number of transformers, the current values in the individual branches and/or the individual output alternating currents can be compared by means of a comparator or a comparison circuit. This is particularly advantageous in the case of very high currents (several tens of kA or several hundreds of kA) in resistance welding, since a failure of one transformer can very quickly lead to an overload and thus to a failure of the other transformer.
The invention thus allows the parallel branches to be monitored in real time by means of a "branch monitor", and in this way a fast and reliable check of the circuit or wiring link of the alternating current source (such as an inverter) up to and including the transformer can be achieved. A particular advantage here is that already with the invention it is possible to reliably detect small changes in the resistance in the parallel branches. Thus, an inverter, which for example loads a transformer with an input alternating current, can also be protected against overload.
Thus, the invention further provides the following advantages: faster start-up, faster and more reliable branch wiring check, identification of unbalanced loads during operation, identification of component failure in one or more of the parallel branches or transformers, and thereby also improved operability. In particular, the invention reduces maintenance costs and thus results in a more satisfactory, more robust and more cost effective apparatus for the customer.
Preferably, the comparator is set up to: comparing the magnitude of a parameter indicative of the first output alternating current with the magnitude of a parameter indicative of the second output alternating current and/or comparing the power of said parameter indicative of the first output alternating current with the power of said parameter indicative of the second output alternating current. If, in one embodiment, more than two transformers are designed in parallel, it is also possible, for example, to compare more than two and/or all of the output alternating currents with one another or with a reference value.
Preferably, the first transformer and/or the second transformer are/is designed as an intermediate frequency transformer.
Preferably, the input alternating current is provided by means of an inverter. Particularly preferably, the first part of the input alternating current and the second part of the input alternating current have the same amplitude and/or frequency and/or phase.
In this case, the signal is preferably output only if the comparison value indicates that the variable characterizing the first output alternating current deviates by more than 80%, preferably more than 50%, particularly preferably more than 25%, even more preferably more than 10%, most preferably more than 5%, from the variable characterizing the second output alternating current. For example, deviations of the respective output alternating current from a reference value additionally provided can also be determined.
Preferably, outputting the signal indicates an asymmetric load characteristic between the first transformer and the second transformer. Particularly preferably, the signal is set up to cause an adaptation of the first part of the input alternating current and/or the second part of the input alternating current for reducing the asymmetric load characteristic. For this purpose, the signal can be transmitted, for example, to a control unit, for example an external control unit, which can then overcome the asymmetrical load distribution.
The computing device, for example, the control device, according to the invention is designed, in particular, in a program-controlled manner, to carry out the method according to the invention. For example, the computing device can be set up to control a device for converting and/or supplying an electric current (such as a welding current).
In particular, if the control device which is implemented is also used for other tasks and is therefore always present, it is also advantageous to implement the method in the form of a computer program, since this results in particularly low costs. In particular, data carriers suitable for providing the computer program are magnetic, optical and electrical memories, such as a hard disk, flash memory, EEPROM, DVD, and others. It is also possible to download the program via a computer network (internet, intranet, etc.).
Further advantages and embodiments of the invention emerge from the description and the enclosed drawing.
It is readily understood that the features mentioned above and those yet to be explained below can be used not only in the respectively specified combination but also in other combinations or alone without departing from the scope of protection of the present invention.
Drawings
The invention is schematically illustrated in the drawings according to an embodiment and is described in detail below with reference to the drawings.
Fig. 1 shows a schematic circuit diagram of a preferred embodiment of the device according to the invention;
fig. 2 shows a schematic circuit diagram of a second preferred embodiment of the device according to the invention.
Detailed Description
Fig. 1 shows a schematic diagram of a circuit diagram of a first preferred embodiment of the device according to the invention. The input alternating current is provided by means of an alternating current source or alternating voltage source 2. Both the transformers 4a and 4b, which are connected in parallel on the output side as well as on the output side, are loaded with the supplied input alternating current and convert the supplied input alternating current into an output alternating current. The first transformer 4a converts a first part of the input alternating current into a first output alternating current, wherein the current amplitude of the first output alternating current differs from the amplitude of the input alternating current.
Here, similarly, the second transformer 4b converts a second part of the input alternating current into a second output alternating current, wherein the current magnitude of the second output alternating current is different from the magnitude of the input alternating current. Preferably, the transformers 4a and 4b are identically constructed, so that the first and the second output alternating currents are also identical in their amplitude.
After the current conversion by the two transformers 4a and 4b, the parallel branches are grouped together again, so that the entire output alternating current which has been converted by the two transformers 4a and 4b is ready at a common alternating current output 8 and can be used, for example, as a welding current.
The device also has a comparator 6, which comparator 6 compares a first output alternating current of the first transformer 4a as a variable characterizing the output alternating current with a second output alternating current of the second transformer 4b as a variable characterizing the output alternating current. As long as the first output alternating current is equal to the second output alternating current, no current flows through the comparator and the comparator produces no comparison value or one that indicates that the output alternating currents are equal.
However, as long as the first output alternating current is not equal to the second output alternating current, a current flows through the comparator and the comparator produces a comparison value which indicates the difference of the two output alternating currents in a qualitative and/or quantitative manner. Such a difference may for example be caused by damage or interference in at least one of the transformers 4a and 4 b.
The signal unit 10 may output a signal 12 based on the comparison value determined by the comparator and provided to the signal unit 10. The signal 12 may for example be provided to a control unit which then for example operates the alternating voltage source 2 in order to overcome the inequality of the output alternating current or to stop the input voltage supply or the input current supply.
In this way it is possible to prevent: due to the reduced functionality of one of the transformers 4a and 4b, an overload of the respective other transformer occurs and leads to a destruction of the other transformer.
Fig. 2 shows a schematic diagram of a circuit diagram of a second preferred embodiment. The elements already shown in fig. 1 are also denoted by the same reference numerals in fig. 2 and are not explained again.
In the embodiment shown, the alternating current source 2 is designed as an inverter. In this case, the inverter 2 applies a first or second part of the input alternating current to the input of the parallel-connected transformers 4a and 4b on the input side. In the embodiment shown, a diode 16 is formed at the output of the transformers 4a and 4b, by means of which diode 16 the output alternating current can be rectified. The welding diodes of the resistance welding device, in particular the pincer legs (zangenshenkel), can be connected to the outputs + and-. The outputs may be connected in parallel (+/+ and-/-) in order to increase the current.
Furthermore, in the circuit, the first current sensor 14a and the second current sensor 14b are configured as measuring coils in order to compare the rectified output alternating current as a variable characterizing the output alternating current. The output signals of the current sensors 14a and 14b are supplied to a comparator 6, which comparator 6 determines a comparison value on the basis of the output signals of the current sensors 14a and 14b and thus on the basis of the output alternating currents of the first transformer 4a and the second transformer 4 b.
The comparison values are supplied to a signal unit 10, which signal unit 10 outputs different signals depending on the value of the comparison values or does not output a signal as long as it is not necessary. However, especially when an asymmetric load distribution exists between the transformer 4a and the transformer 4b or between the two parallel branches, a signal may be output which may be provided to the inverter 2, for example. Depending on the provided signal, the inverter may, for example, control or regulate the input alternating current such that an asymmetric load distribution between the transformer 4a and the transformer 4b is overcome. In particular, the input alternating current can be increased or decreased correspondingly, when the associated output alternating current is smaller or larger than the other output alternating current.
Claims (13)
1. A device for converting an input alternating current, the device comprising:
-a first transformer (4 a), the first transformer (4 a) being set up to convert a first part of the input alternating current into a first output alternating current;
-a second transformer (4 b), the second transformer (4 b) being set up to convert a second part of the input alternating current into a second output alternating current, wherein the second transformer is connected in parallel with the first transformer on the input side;
-a comparator (6), the comparator (6) being set up to compare a quantity characterizing the first output alternating current with a quantity characterizing the second output alternating current and to determine a comparison value on the basis thereof; and
-a signal unit (10), the signal unit (10) being set up to output a signal based on the comparison value.
2. The apparatus as claimed in claim 1, wherein the comparator (6) is set up to: comparing the magnitude of the parameter indicative of the first output alternating current with the magnitude of the parameter indicative of the second output alternating current; and/or comparing the power of the quantity characteristic of the first output alternating current with the power of the quantity characteristic of the second output alternating current.
3. The device according to claim 1 or 2, wherein the first transformer (4 a) and/or the second transformer (4 b) is configured as an intermediate frequency transformer.
4. The device according to claim 1 or 2, wherein the input alternating current is provided by means of an inverter (2); and/or wherein the first part of the input alternating current and the second part of the input alternating current have the same amplitude and/or frequency and/or phase.
5. The device according to claim 1 or 2, wherein the second transformer (4 b) is connected in parallel with the first transformer (4 a) on the output side.
6. A method for converting an input alternating current, the method comprising the steps of:
-converting a first part of the input alternating current into a first output alternating current by means of a first transformer (4 a);
-converting a second part of the input alternating current into a second output alternating current by means of a second transformer (4 b), wherein the second transformer (4 b) is connected in parallel with the first transformer (4 a) on the input side;
-comparing a quantity characteristic of the first output alternating current with a quantity characteristic of the second output alternating current;
-determining a comparison value based on a comparison of the quantity characterizing the first output alternating current and the quantity characterizing the second output alternating current; and also
-outputting a signal based on the determined comparison value as long as the determined comparison value is within a predetermined range.
7. The method of claim 6, wherein said comparing of said quantity characteristic of a first output alternating current with said quantity characteristic of a second output alternating current comprises: a comparison of the magnitude of the quantity characterizing the first output alternating current with the magnitude of the quantity characterizing the second output alternating current and/or a comparison of the power of the quantity characterizing the first output alternating current with the power of the quantity characterizing the second output alternating current.
8. A method according to claim 6 or 7, wherein said signal is output only if said comparison value indicates that said quantity characteristic of the first output alternating current differs from said quantity characteristic of the second output alternating current by more than 50%.
9. A method according to claim 6 or 7, wherein the signal is output only if the comparison value indicates that the quantity characteristic of the first output alternating current differs from the quantity characteristic of the second output alternating current by more than 25%.
10. A method according to claim 6 or 7, wherein the signal is output only if the comparison value indicates that the quantity characteristic of the first output alternating current differs from the quantity characteristic of the second output alternating current by more than 5%.
11. The method according to claim 6 or 7, wherein outputting the signal is indicative of an asymmetric load characteristic between the first transformer (4 a) and the second transformer (4 b), and the signal is established to cause an adaptation of the input alternating current for reducing the asymmetric load characteristic.
12. A computing device set up to perform the method according to one of claims 6 to 11.
13. A machine readable storage medium having stored thereon a computer program which, when implemented on a computing device, causes the computing device to perform the method of one of claims 6 to 11.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE102016206024.4A DE102016206024A1 (en) | 2016-04-12 | 2016-04-12 | Apparatus and method for converting an alternating electrical current |
| DE102016206024.4 | 2016-04-12 |
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| Publication Number | Publication Date |
|---|---|
| CN107294397A CN107294397A (en) | 2017-10-24 |
| CN107294397B true CN107294397B (en) | 2021-03-30 |
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| CN201710232241.2A Active CN107294397B (en) | 2016-04-12 | 2017-04-11 | Device and method for converting an alternating current |
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| DE (1) | DE102016206024A1 (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101243603A (en) * | 2005-08-24 | 2008-08-13 | 三菱电机株式会社 | Dc/DC converter device and discharge lamp lighting device |
| CN101802626A (en) * | 2007-08-30 | 2010-08-11 | Abb股份有限公司 | Device for identifying an asymmetrical load in a three-phase system |
| CN203260456U (en) * | 2013-05-09 | 2013-10-30 | 江苏宝亨新电气有限公司 | 6-10 kV double-voltage dry type transformer coil structure with same linking group |
| CN103683479A (en) * | 2013-12-23 | 2014-03-26 | 大连大学 | Current-sharing control method for parallel redundant power supply |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW513834B (en) * | 2001-03-30 | 2002-12-11 | Delta Electronics Inc | Failure protection device of parallel type power supply |
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2016
- 2016-04-12 DE DE102016206024.4A patent/DE102016206024A1/en active Pending
-
2017
- 2017-04-11 CN CN201710232241.2A patent/CN107294397B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101243603A (en) * | 2005-08-24 | 2008-08-13 | 三菱电机株式会社 | Dc/DC converter device and discharge lamp lighting device |
| CN101802626A (en) * | 2007-08-30 | 2010-08-11 | Abb股份有限公司 | Device for identifying an asymmetrical load in a three-phase system |
| CN203260456U (en) * | 2013-05-09 | 2013-10-30 | 江苏宝亨新电气有限公司 | 6-10 kV double-voltage dry type transformer coil structure with same linking group |
| CN103683479A (en) * | 2013-12-23 | 2014-03-26 | 大连大学 | Current-sharing control method for parallel redundant power supply |
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| Publication number | Publication date |
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| CN107294397A (en) | 2017-10-24 |
| DE102016206024A1 (en) | 2017-10-12 |
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