CN116169699A - High-voltage direct-hanging energy storage converter and field detection method - Google Patents
High-voltage direct-hanging energy storage converter and field detection method Download PDFInfo
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- CN116169699A CN116169699A CN202211688958.5A CN202211688958A CN116169699A CN 116169699 A CN116169699 A CN 116169699A CN 202211688958 A CN202211688958 A CN 202211688958A CN 116169699 A CN116169699 A CN 116169699A
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/28—Arrangements for balancing of the load in a network by storage of energy
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
- H02J3/46—Controlling of the sharing of output between the generators, converters, or transformers
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/34—Parallel operation in networks using both storage and other dc sources, e.g. providing buffering
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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
- H02M1/08—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
- H02M1/088—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters for the simultaneous control of series or parallel connected semiconductor devices
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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
- 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
-
- 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
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/53—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
- H02M7/537—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
- H02M7/5387—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
Abstract
The invention discloses a high-voltage direct-hanging energy storage converter and a field detection method. According to the invention, a star-shaped connection or an angle-shaped connection is formed by a plurality of converter chains, and the first alternating current switch and the second alternating current switch are arranged, so that when the converter is in standby, whether main devices in the energy storage converter are normal can be verified by controlling the circulation between the converter chains, the testing efficiency is high, and the operation difficulty is low.
Description
Technical Field
The invention relates to the technical field of high-power electronic converter, in particular to a high-voltage direct-hanging energy storage converter and a field detection method.
Background
In the technical field of high-capacity high-power electronic converter, the multi-level converter integrates an energy storage unit in a submodule by using a modularized cascading technology, has the advantages of high modularization degree, good harmonic characteristic, low equivalent switching frequency and the like, and is a standard topology in the field of high-voltage power electronics. By integrating the energy storage unit as a sub-module in the modular multilevel converter, both ac-dc power conversion and energy storage can be achieved.
The high-voltage direct-hanging energy storage converter is a feasible scheme capable of effectively meeting the access requirement of an energy storage system and relieving or isolating fault propagation between alternating current and direct current systems. When the high-voltage direct-hanging energy storage converter is required to be put into operation or withdrawn, the power unit and the energy storage unit are in a standby state for a long time and are not operated for a long time, whether the power unit and the energy storage unit are damaged or not cannot be judged, and when the high-voltage direct-hanging energy storage converter is required to be put into operation, if the device is damaged, the equipment cannot realize the functions of voltage support and power support, so that the equipment is required to be subjected to field detection; in the prior art, in order to ensure equipment and personal safety, when the converter is subjected to field detection, the connection with an alternating current power grid can be disconnected, and after the disconnection, each sub-module can be independently tested, so that the testing efficiency is low and the testing difficulty is high.
Disclosure of Invention
Aiming at the problem of lower efficiency when the current transformer is subjected to field detection in the prior art, the invention provides the high-voltage direct-hanging energy storage current transformer and the field detection method, wherein a star connection or an angle connection is formed by a plurality of current conversion chains, and a first alternating current switch and a second alternating current switch are arranged.
The following is a technical scheme of the invention.
The utility model provides a high-voltage direct-hanging energy storage converter, includes a plurality of commutation chains, a plurality of commutation chains constitute star connection or angle connection, the three-phase AC output of converter is connected with the electric wire netting through first AC switch, still connects the second AC switch between AC output A phase and B phase, B phase and C phase, C phase and the A phase.
Preferably, the converter chain comprises N sub-modules, wherein N is an integer greater than or equal to 2, and the sub-modules comprise an energy storage unit, a power unit, an interface unit, a bypass switch and a sub-module control unit.
Preferably, the power unit is a full-bridge circuit formed by a direct-current capacitor and four power semiconductor switching devices; the energy storage unit is connected with the direct current side of the power unit through the interface unit, and the submodule control unit takes energy from the direct current capacitor and the energy storage unit; the bypass switch is connected in parallel with the alternating current side of the power unit.
Preferably, the energy storage unit is a battery or a super capacitor.
Preferably, the interface unit is a filter or a dc converter composed of an inductance and/or a capacitance, and the dc converter is isolated or non-isolated.
The invention also provides a field detection method of the high-voltage direct-hanging energy storage converter, which is used for the high-voltage direct-hanging energy storage converter and comprises the following steps:
step 1: opening the first alternating current switch;
step 2: closing a second alternating current switch between the alternating current output phase A and the alternating current output phase B, the alternating current output phase B and the alternating current output phase C, and the alternating current output phase C and the alternating current output phase A;
step 3: the interface unit in the converter chain is put into, and the unlocking of the power semiconductor device in the power unit of the converter chain is controlled;
step 4: controlling power semiconductor devices in power units of the converter chains to enable energy storage units in the converter chains to enter a charge-discharge state, and forming circulation between the converter chains;
step 5: controlling the circulation current to be stabilized to a test set value;
step 6: detecting the running states of all sub-modules in the converter chain, and when the number of the fault sub-modules exceeds an action threshold value, stopping and overhauling.
Preferably, in the step 5, the test set point ranges from 5% to 20% of the rated current of the converter.
Preferably, in the step 6, the action threshold value is determined by the number of fault sub-modules allowed by each converter chain.
The essential effects of the invention include:
(1) The method provided by the invention does not need to increase extra cost, can enable the power semiconductor devices and the energy storage units in the power units to work in batches, forms a circulation flow between the converter chains through the control method, is simple and easy to realize, and greatly improves the reliability of the device.
(2) When the device detects, the alternating current switch is disconnected, the influence on the power grid side is avoided, after the abnormality of the submodule is detected, the fault is reported, and equipment can be overhauled in the period.
(3) In the detection process, current flows through the energy storage unit, the interface unit and the power unit, and when any unit of the equipment fails, detection can be effectively realized, and comprehensive and accurate detection can be carried out on the equipment.
Drawings
Fig. 1 is a schematic diagram of an inverter according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of an interface unit according to an embodiment of the present invention;
fig. 3 is a schematic diagram of another interface unit according to an embodiment of the present invention.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solution will be clearly and completely described in the following in conjunction with the embodiments, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It should be understood that, in various embodiments of the present invention, the sequence number of each process does not mean that the execution sequence of each process should be determined by its functions and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.
It should be understood that in the present invention, "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements that are expressly listed or inherent to such process, method, article, or apparatus.
It should be understood that in the present invention, "plurality" means two or more. "and/or" is merely an association relationship describing an association object, and means that three relationships may exist, for example, and/or B may mean: a exists alone, A and B exist together, and B exists alone. The character "/" generally indicates that the context-dependent object is an "or" relationship. "comprising A, B and C", "comprising A, B, C" means that all three of A, B, C comprise, "comprising A, B or C" means that one of the three comprises A, B, C, and "comprising A, B and/or C" means that any 1 or any 2 or 3 of the three comprises A, B, C.
The technical scheme of the invention is described in detail below by specific examples. Embodiments may be combined with each other and the same or similar concepts or processes may not be described in detail in some embodiments.
Examples:
the utility model provides a high-voltage direct-hanging energy storage converter, is shown as fig. 1, includes 3 commutation chains, 3 commutation chains constitute star connection or angle connection, the three-phase AC output of converter is connected with the electric wire netting through first AC switch, and AC output A phase is with B phase, B phase is with C phase, C phase still connects the second AC switch between the A phase.
The converter chain comprises N submodules, N is an integer greater than or equal to 2, and the submodules comprise an energy storage unit, a power unit, an interface unit, a bypass switch and a submodule control unit.
The power unit is a full-bridge circuit formed by a direct-current capacitor and four power semiconductor switching devices; the energy storage unit is connected with the direct current side of the power unit through the interface unit, and the submodule control unit takes energy from the direct current capacitor and the energy storage unit; the bypass switch is connected in parallel with the alternating current side of the power unit.
The energy storage unit is a battery or a super capacitor.
The interface unit is a filter or a dc converter formed by an inductance and/or a capacitance, and the dc converter is an isolated or non-isolated type, as shown in fig. 2 and 3, respectively.
The embodiment also provides a field detection method for the high-voltage direct-hanging energy storage converter, which is used for the high-voltage direct-hanging energy storage converter and comprises the following steps:
step 1: opening the first alternating current switch;
step 2: closing a second alternating current switch between the alternating current output phase A and the alternating current output phase B, the alternating current output phase B and the alternating current output phase C, and the alternating current output phase C and the alternating current output phase A;
step 3: the interface unit in the converter chain is put into, and the unlocking of the power semiconductor device in the power unit of the converter chain is controlled;
step 4: controlling power semiconductor devices in power units of the converter chains to enable energy storage units in the converter chains to enter a charge-discharge state, and forming circulation between the converter chains;
step 5: controlling the circulation current to be stabilized to a test set value;
step 6: detecting the running states of all sub-modules in the converter chain, and when the number of the fault sub-modules exceeds an action threshold value, stopping and overhauling.
In addition, in step 5, the test set point ranges from 5% to 20% of the rated current of the current transformer.
In step 6, the action threshold value is determined by the number of fault sub-modules allowed by each converter chain.
The essential effects of the present embodiment include:
(1) The method provided by the invention does not need to increase extra cost, can enable the power semiconductor devices and the energy storage units in the power units to work in batches, forms a circulation flow between the converter chains through the control method, is simple and easy to realize, and greatly improves the reliability of the device.
(2) When the device detects, the alternating current switch is disconnected, the influence on the power grid side is avoided, after the abnormality of the submodule is detected, the fault is reported, and equipment can be overhauled in the period.
(3) In the detection process, current flows through the energy storage unit, the interface unit and the power unit, and when any unit of the equipment fails, detection can be effectively realized, and comprehensive and accurate detection can be carried out on the equipment.
From the foregoing description of the embodiments, it will be appreciated by those skilled in the art that, for convenience and brevity of description, only the above-described division of functional modules is illustrated, and in practical application, the above-described functional allocation may be implemented by different functional modules according to needs, i.e. the internal structure of a specific apparatus is divided into different functional modules to implement all or part of the functions described above.
In the embodiments provided in this application, it should be understood that the disclosed structures and methods may be implemented in other ways. For example, the embodiments described above with respect to structures are merely illustrative, e.g., the division of modules or units is merely a logical functional division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another structure, or some features may be omitted, or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via interfaces, structures or units, which may be in electrical, mechanical or other forms.
The units described as separate parts may or may not be physically separate, and the parts shown as units may be one physical unit or a plurality of physical units, may be located in one place, or may be distributed in a plurality of different places. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.
In addition, each functional unit in the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.
The integrated units, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a readable storage medium. Based on such understanding, the technical solution of the embodiments of the present application may be essentially or a part contributing to the prior art or all or part of the technical solution may be embodied in the form of a software product stored in a storage medium, including several instructions to cause a device (may be a single-chip microcomputer, a chip or the like) or a processor (processor) to perform all or part of the steps of the methods of the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read Only Memory (ROM), a random access memory (random access memory, RAM), a magnetic disk, or an optical disk, or other various media capable of storing program codes.
The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the present application, and the changes and substitutions are intended to be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.
Claims (8)
1. The high-voltage direct-hanging energy storage converter is characterized by comprising a plurality of converter chains, wherein the converter chains are connected in a star-shaped or angle-shaped manner, three-phase alternating current output of the converter is connected with a power grid through a first alternating current switch, and a second alternating current switch is further connected between an alternating current output phase A and a phase B, between a phase B and a phase C and between a phase C and a phase A.
2. The high-voltage direct-hanging energy storage converter of claim 1, wherein the converter chain comprises N sub-modules, N is an integer greater than or equal to 2, and the sub-modules comprise an energy storage unit, a power unit, an interface unit, a bypass switch and a sub-module control unit.
3. The high-voltage direct-hanging energy storage converter of claim 2, wherein the power unit is a full-bridge circuit consisting of a direct-current capacitor and four power semiconductor switching devices; the energy storage unit is connected with the direct current side of the power unit through the interface unit, and the submodule control unit takes energy from the direct current capacitor and the energy storage unit; the bypass switch is connected in parallel with the alternating current side of the power unit.
4. The high voltage direct-hanging energy storage converter of claim 2, wherein the energy storage unit is a battery or a super capacitor.
5. A high voltage direct hanging energy storage converter as claimed in claim 3, wherein the interface unit is a filter or a dc converter composed of an inductance and/or a capacitance, the dc converter being isolated or non-isolated.
6. A method for in-situ detection of a high voltage direct-hanging energy storage converter as claimed in any one of claims 1-5, comprising the steps of:
step 1: opening the first alternating current switch;
step 2: closing a second alternating current switch between the alternating current output phase A and the alternating current output phase B, the alternating current output phase B and the alternating current output phase C, and the alternating current output phase C and the alternating current output phase A;
step 3: the interface unit in the converter chain is put into, and the unlocking of the power semiconductor device in the power unit of the converter chain is controlled;
step 4: controlling power semiconductor devices in power units of the converter chains to enable energy storage units in the converter chains to enter a charge-discharge state, and forming circulation between the converter chains;
step 5: controlling the circulation current to be stabilized to a test set value;
step 6: detecting the running states of all sub-modules in the converter chain, and when the number of the fault sub-modules exceeds an action threshold value, stopping and overhauling.
7. The method according to claim 6, wherein in the step 5, the test set point is in a range of 5% to 20% of the rated current of the converter.
8. The method for on-site detection of a high voltage direct hanging energy storage converter as claimed in claim 6, wherein in said step 6, the action threshold is determined by the number of fault sub-modules allowed per commutation chain.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211688958.5A CN116169699A (en) | 2022-12-27 | 2022-12-27 | High-voltage direct-hanging energy storage converter and field detection method |
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| CN202211688958.5A CN116169699A (en) | 2022-12-27 | 2022-12-27 | High-voltage direct-hanging energy storage converter and field detection method |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118017575A (en) * | 2024-04-08 | 2024-05-10 | 中国华能集团清洁能源技术研究院有限公司 | Debugging circuit and method of cascade high-voltage direct-hanging energy storage system |
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- 2022-12-27 CN CN202211688958.5A patent/CN116169699A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118017575A (en) * | 2024-04-08 | 2024-05-10 | 中国华能集团清洁能源技术研究院有限公司 | Debugging circuit and method of cascade high-voltage direct-hanging energy storage system |
| CN118017575B (en) * | 2024-04-08 | 2024-06-11 | 中国华能集团清洁能源技术研究院有限公司 | Debugging circuit and method of cascade high-voltage direct-hanging energy storage system |
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