CN116256689A - Self-checking method of converter, converter and equipment - Google Patents
Self-checking method of converter, converter and equipment Download PDFInfo
- Publication number
- CN116256689A CN116256689A CN202310105206.XA CN202310105206A CN116256689A CN 116256689 A CN116256689 A CN 116256689A CN 202310105206 A CN202310105206 A CN 202310105206A CN 116256689 A CN116256689 A CN 116256689A
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- Prior art keywords
- current transformer
- preset
- signal
- analog signal
- current
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R35/00—Testing or calibrating of apparatus covered by the other groups of this subclass
- G01R35/02—Testing or calibrating of apparatus covered by the other groups of this subclass of auxiliary devices, e.g. of instrument transformers according to prescribed transformation ratio, phase angle, or wattage rating
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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
- G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
- G01R31/55—Testing for incorrect line connections
Abstract
The invention discloses a self-checking method of a current transformer, the current transformer and equipment, comprising the following steps: before the machine set is started, a testing loop is controlled to send a preset electric signal to a current transformer; and acquiring an analog signal output by the current transformer, and judging whether the current transformer fails or not according to the analog signal and the preset signal. According to the invention, the characteristic that the current output by the current transformer is only influenced by the resistance value of the winding is utilized, and the reference judgment is carried out according to the correlation between the analog quantity signal output by the current transformer and the resistance value. Therefore, whether the current transformer is faulty or not, such as wiring fault or wrong selection proportion, can be judged by judging the deviation of the analog quantity and the preset signal in the normal state, and larger loss of equipment is avoided.
Description
Technical Field
The present invention relates to the field of detection control of converters, and in particular, to a self-checking method for a converter, a converter and a device thereof.
Background
The internal current transformer of the current transformer is an important component part, and in fact, due to the component characteristics of the current transformer, the wiring of the current transformer is complicated, and the fault generated by the wiring error of the current transformer is likely to be an unrecoverable fault, so that in order to avoid the fault hazard generated by wiring error, a self-checking method of the current transformer of the high-power photovoltaic current transformer is required to protect the current transformer. The method aims at ensuring the starting safety of the converter and providing the first time to detect faults so as to avoid larger losses.
Disclosure of Invention
The invention provides a self-checking method of a current transformer, the current transformer and equipment, and aims to solve the technical problem that the current transformer cannot be prevented from faults caused by wiring errors in the prior art.
The technical scheme adopted by the invention is as follows:
the invention provides a self-checking method of a converter, which comprises the following steps:
before the machine set is started, a testing loop is controlled to send a preset electric signal to a current transformer;
and acquiring an analog signal output by the current transformer, and judging whether the current transformer fails or not according to the deviation between the analog signal and a preset signal.
Further, the step of judging whether the current transformer has a fault according to the magnitude of the analog signal and the magnitude of the preset signal specifically includes: when the difference value between the analog signal and the preset signal is smaller than the preset difference value, the current transformer is judged to be normal in wiring, and the starting-up of the unit is controlled.
Specifically, the step of judging whether the current transformer is in error or not according to the magnitudes of the analog signal and the preset signal specifically comprises the following steps: and when the analog signal is equal to 0 or smaller than a preset value, judging that the current transformer has wiring faults, and outputting a rewiring instruction.
Specifically, the step of judging whether the current transformer is in error or not according to the magnitudes of the analog signal and the preset signal specifically comprises the following steps: when the difference value between the analog signal and the preset signal is larger than the preset difference value and the analog signal is not equal to 0, a second preset electric signal is sent to the current transformer, and then the current analog signal output by the current transformer is obtained to judge the fault state of the current transformer.
Further, the obtaining the analog signal output by the current transformer to judge the fault state of the current transformer specifically includes: and judging that the current analog signal and the preset signal have a difference value larger than the preset difference value, and judging that the current transformer has a fault or is in wrong wiring.
Further, the difference value between the current analog signal and the preset signal is smaller than the preset difference value, and the current transformer is judged to be wrong in model selection.
Further, the second preset electrical signal is the maximum rated current of the current transformer.
Further, the preset electrical signal is a constant current.
The invention also provides a converter, and the state of the current transformer is judged by using the self-checking method of the converter.
The invention also provides equipment comprising the converter.
Compared with the prior art, the invention carries out reference judgment according to the correlation between the analog quantity signal output by the current transformer and the resistance value by utilizing the characteristic that the current output by the current transformer is only influenced by the resistance value of the winding. Therefore, whether the current transformer is faulty or not, such as wiring fault or wrong selection proportion, can be judged by judging the deviation of the analog quantity and the preset signal in the normal state, and larger loss of equipment is avoided.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments or the description of the prior art will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a flow chart of an embodiment of the present invention.
Detailed Description
In order to make the technical problems, technical schemes and beneficial effects to be solved more clear, the invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
The principles and structures of the present invention are described in detail below with reference to the drawings and the examples.
The existing current transformer, such as a photovoltaic current transformer, has a wiring self-checking problem inside, the current transformer inside is an important component part, and in fact, due to the component characteristics of the current transformer, the wiring of the current transformer is complicated, and faults generated by wiring errors of the current transformer are likely to be unrecoverable faults, so that in order to avoid fault hazards generated by wiring errors, the invention provides a self-checking method of a high-power photovoltaic current transformer to protect the current transformer, and aims to ensure the starting safety of the current transformer and provide a first time for detecting faults to avoid larger losses.
As shown in fig. 1, the present invention provides a self-checking method of a current transformer, including the steps of:
before the machine set is started, an internal test loop is controlled to send out a preset electric signal to a current transformer;
and acquiring an analog signal output by the current transformer, and judging whether the current transformer fails or not according to the analog signal and the preset signal.
The preset electric signal is a section of constant current, after the current transformer is electrified, a constant current sent by a test loop on the trigger main board flows through the current transformer, and under the condition that the resistance voltage is unchanged, the current output by the current transformer is only influenced by the resistance value of the winding, so that the analog quantity signal output by the current transformer is related to the resistance value and can be used for reference judgment. Therefore, by judging the deviation of the analog quantity and the preset signal in the normal state, whether the current transformer is faulty or not, such as wiring fault or wrong selection proportion, can be judged.
Specifically, judging whether the current transformer has a fault according to the magnitude of the analog signal and the preset signal specifically includes: when the difference value between the analog signal and the preset signal is smaller than the preset deviation, the numerical value of the analog signal is in a normal range, namely the resistance value of the winding is normal, the wiring error of the current transformer is not generated, the ratio selection error of the current transformer is not generated, the normal starting can be judged, the main board can send a normal starting instruction, the intermediate relay of the main circuit is closed, and the unit is electrified and started.
When the analog signal is equal to 0 or smaller than a preset value, namely when the analog signal is completely absent or very small, wiring errors can occur, for example, a current transformer is not connected completely, faults are judged, rewiring is prompted, meanwhile, the unit is automatically powered off, and the faults are prevented from affecting normal operation of subsequent equipment.
When the difference between the analog signal and the preset signal is larger than the preset deviation and the analog signal is not equal to 0 (or is larger than or equal to the preset value), namely the value is larger than or smaller than the normal range, the fault of the current transformer is judged, and the specific fault state is further detected.
The further detection of specific fault conditions is specifically: then, a second preset signal is sent to the current transformer again, the second preset signal is the maximum current which can be received by the current transformer, namely the maximum rated current value, the current analog signal output by the current transformer is obtained and compared with the preset signal, if the difference value of the current analog signal and the preset signal is larger than the preset difference value, namely the value is larger than the normal range or the value is smaller than the normal range, the current transformer fault (the fault can be a hardware fault specifically, such as the damage of the current transformer) or the wiring error is judged, and the fault element needs to be rewired or directly replaced; if the difference between the current analog signal and the preset signal is smaller than the preset difference, namely in the normal range, the current transformer ratio is judged to be selected incorrectly, namely the type is selected incorrectly, if the current transformer is used continuously, the detection precision is affected, and the current transformer with the correct ratio needs to be replaced.
The comparison result of the analog quantity and the calculated value sent by the current transformer is used as the judgment basis of the protection program started by the frequency converter unit, so that the algorithm operation performed according to the fact that the current transformer sends out the wrong analog quantity is avoided, and the influence on the operation of the unit due to the overlarge or the overlarge current calculation result is avoided.
The invention also provides a current transformer, and the self-checking method of the current transformer is used for detecting the fault of the current transformer.
In a specific embodiment, the converter may be a photovoltaic converter applied to a photovoltaic air conditioner.
The invention also provides equipment comprising the converter.
In a specific embodiment, the device may be a photovoltaic air conditioner in particular.
It is noted that the above-mentioned terms are used merely to describe specific embodiments, and are not intended to limit exemplary embodiments according to the present invention. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.
The relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless it is specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective parts shown in the drawings are not drawn in actual scale for convenience of description. Techniques, methods, and apparatus known to one of ordinary skill in the relevant art may not be discussed in detail, but should be considered part of the specification where appropriate. In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.
In the description of the present invention, it should be understood that the azimuth or positional relationships indicated by the azimuth terms such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal", and "top, bottom", etc., are generally based on the azimuth or positional relationships shown in the drawings, merely to facilitate description of the present invention and simplify the description, and these azimuth terms do not indicate and imply that the apparatus or elements referred to must have a specific azimuth or be constructed and operated in a specific azimuth, and thus should not be construed as limiting the scope of protection of the present invention; the orientation word "inner and outer" refers to inner and outer relative to the contour of the respective component itself.
Spatially relative terms, such as "above … …," "above … …," "upper surface at … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial location relative to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "over" other devices or structures would then be oriented "below" or "beneath" the other devices or structures. Thus, the exemplary term "above … …" may include both orientations of "above … …" and "below … …". The device may also be positioned in other different ways (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
In addition, the terms "first", "second", etc. are used to define the components, and are only for convenience of distinguishing the corresponding components, and the terms have no special meaning unless otherwise stated, and therefore should not be construed as limiting the scope of the present invention.
The above description is only of the preferred embodiments of the present invention and is not intended to limit the present invention, but various modifications and variations can be made to the present invention by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. The self-checking method of the converter is characterized by comprising the following steps:
before the machine set is started, a testing loop is controlled to send a preset electric signal to a current transformer;
and acquiring an analog signal output by the current transformer, and judging whether the current transformer fails or not according to the deviation between the analog signal and a preset signal.
2. The self-checking method of the current transformer according to claim 1, wherein the determining whether the current transformer has a fault according to the magnitude of the analog signal and the magnitude of the preset signal comprises: and when the difference value between the analog signal and the preset signal is smaller than the preset difference value, judging that the wiring of the current transformer is normal, and controlling the starting-up of the unit.
3. The self-checking method of the current transformer according to claim 1, wherein the step of determining whether the current transformer is miswired according to the magnitude of the analog signal and the magnitude of the preset signal comprises: and when the analog signal is equal to 0 or smaller than a preset value, judging that the current transformer has wiring faults, and outputting a rewiring instruction.
4. The self-checking method of the current transformer according to claim 1, wherein the step of determining whether the current transformer is miswired according to the magnitude of the analog signal and the magnitude of the preset signal comprises: when the difference value between the analog signal and the preset signal is larger than the preset difference value and the analog signal is not equal to 0, a second preset electric signal is sent to the current transformer, and then the current analog signal output by the current transformer is obtained to judge the fault state of the current transformer.
5. The method for self-checking a current transformer according to claim 4, wherein obtaining the analog signal output from the current transformer to determine the fault state of the current transformer comprises: and judging that the current analog signal and the preset signal have a difference value larger than the preset difference value, and judging that the current transformer has a fault or is in wrong wiring.
6. The method of claim 4, wherein the difference between the current analog signal and the preset signal is smaller than the preset difference, and the current transformer is determined to be in error.
7. The method of self-test of a current transformer according to claim 4, wherein said second predetermined electrical signal is a maximum rated current of said current transformer.
8. The method of claim 1, wherein the predetermined electrical signal is a constant current.
9. A current transformer characterized in that the state of the current transformer is judged using the self-test method of the current transformer according to any one of claims 1 to 8.
10. An apparatus comprising the current transformer of claim 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310105206.XA CN116256689A (en) | 2023-02-13 | 2023-02-13 | Self-checking method of converter, converter and equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310105206.XA CN116256689A (en) | 2023-02-13 | 2023-02-13 | Self-checking method of converter, converter and equipment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116256689A true CN116256689A (en) | 2023-06-13 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310105206.XA Pending CN116256689A (en) | 2023-02-13 | 2023-02-13 | Self-checking method of converter, converter and equipment |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116256689A (en) |
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2023
- 2023-02-13 CN CN202310105206.XA patent/CN116256689A/en active Pending
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