1. A method of detecting a gap in a magnetic core of a transformer, the method comprising the steps of:

s1, connecting the input end of a final assembly product containing a transformer with a working power supply, and connecting the output end of the final assembly product with a load;

s2, electrifying the final assembly product to work, and electrifying the transformer to operate;

s3, acquiring the input current of the primary side of the transformer;

s4, converting the input current into a current value;

s5, judging whether the current value is within a preset threshold range, and if so, judging that the magnetic core gap of the transformer is qualified; and if not, determining that the magnetic core gap of the transformer is unqualified.

2. The method of claim 1, further comprising between the step of S3 and the step of S4: and filtering the input current.

3. The method for detecting a gap in a core of a transformer according to claim 1, wherein said step S5 is followed by the step of: and when the magnetic core gap of the transformer is judged to be unqualified, an alarm signal is sent out.

4. The method of claim 1, wherein the transformer is a high frequency transformer, a medium frequency transformer, or a low frequency transformer.

5. The method of claim 1, wherein the core structure of the transformer is UI type, EE type or EI type.

6. The method of claim 1, wherein the transformer in the final assembly comprises a primary side and two or more secondary sides, each secondary side corresponding to an output of the final assembly; the S1 specifically includes the following steps: and connecting the input end of the final assembly product with a working power supply, and respectively connecting each output end of the final assembly product with a load.

7. The device for detecting the gap of the magnetic core of the transformer is characterized by comprising a current acquisition module, an A/D conversion module and a microprocessor which are sequentially connected in series;

the current acquisition module is used for acquiring the input current of the primary side of the transformer;

the A/D conversion module is used for converting the input current into a current value;

the microprocessor is used for judging whether the current value is within a preset threshold range, and if so, judging that the magnetic core gap of the transformer is qualified; and if not, determining that the magnetic core gap of the transformer is unqualified.

8. The apparatus of claim 7, further comprising a filter circuit coupled in series between the current acquisition module and the a/D conversion module.

9. The apparatus of claim 7, further comprising an alarm module, said alarm module being connected in series with said microprocessor.

10. The apparatus of claim 7, wherein the current acquisition module is a current sensor.

Background

The transformer as a transformer device can be applied to various products. For example, the transformer is a key component of the DC/DC converter, and the reliability of the transformer directly determines the performance of the DC/DC converter. However, in the links of raw material transportation and product production of the transformer, the transformer core is easily affected by external factors, such as core breakage, contamination by particles, or installation tilt, etc., resulting in a change in the core gap (the gap may also be referred to as an air gap, i.e., the distance between two cores). The change of the magnetic core gap has a great influence on the performance of the transformer without or with a small gap, and if the change is serious, the function of the product is abnormal. For example, the core gap of some transformers is designed to be smaller than 100um, and if the core gap becomes larger, the inductance of the transformer is reduced, which may cause problems in the overall electrical performance of the DC/DC converter, such as primary side overcurrent.

However, at present, after the transformer or the product with the transformer as a component is assembled, the gap of the transformer core is not detected, so that part of unqualified products are introduced into the market.

Disclosure of Invention

The invention provides a method and a device for detecting a gap of a magnetic core of a transformer, which aim to solve the technical problem that the gap of the magnetic core of the transformer is not detected.

In order to solve the technical problem, the invention provides a method for detecting the gap of a magnetic core of a transformer, which is characterized by comprising the following steps:

s1, connecting the input end of a final assembly product containing a transformer with a working power supply, and connecting the output end of the final assembly product with a load;

s2, electrifying the final assembly product to work, and electrifying the transformer to operate;

s3, acquiring the input current of the primary side of the transformer;

s4, converting the input current into a current value;

s5, judging whether the current value is within a preset threshold range, and if so, judging that the magnetic core gap of the transformer is qualified; and if not, determining that the magnetic core gap of the transformer is unqualified.

Optionally, between S3 and S4, further comprising: and filtering the input current.

Optionally, after S5, the method further includes: and when the magnetic core gap of the transformer is judged to be unqualified, an alarm signal is sent out.

Optionally, the transformer is a high-frequency transformer, a medium-frequency transformer or a low-frequency transformer.

Optionally, the magnetic core structure of the transformer is UI type, EE type or EI type.

Optionally, the transformer in the final assembly product includes a primary side and more than two secondary sides, and each secondary side corresponds to an output end of the final assembly product; the S1 specifically includes the following steps: and connecting the input end of the final assembly product with a working power supply, and respectively connecting each output end of the final assembly product with a load.

The invention also provides a device for detecting the gap of the magnetic core of the transformer, which comprises a current acquisition module, an A/D conversion module and a microprocessor which are sequentially connected in series;

the current acquisition module is used for acquiring the input current of the primary side of the transformer;

the A/D conversion module is used for converting the input current into a current value;

the microprocessor is used for judging whether the current value is within a preset threshold range, and if so, judging that the magnetic core gap of the transformer is qualified; and if not, determining that the magnetic core gap of the transformer is unqualified.

Optionally, the apparatus further includes a filter circuit, and the filter circuit is connected in series between the current obtaining module and the a/D conversion module.

Optionally, the device further comprises an alarm module, and the alarm module is connected in series with the microprocessor.

Optionally, the current obtaining module is a current sensor.

The invention provides a method and a device for detecting the gap of a magnetic core of a transformer, which have the following principles: firstly, theoretical calculation is carried out according to ideal parameters of the transformer to obtain the maximum value and the minimum value of the primary side current of the transformer; then, carrying out actual detection, setting input voltage of the transformer and output load current of the transformer before the actual detection, then electrifying the transformer, enabling the transformer to work by electrifying, and detecting to obtain primary side current ip, wherein ip is im + is/N, im represents exciting current, is represents secondary side current, and N represents the turn ratio of the primary side to the secondary side; after the actual primary side current ip of the transformer is detected, the current ip in the form of analog quantity is transmitted to an A/D conversion module for analog-to-digital conversion, and a current value of digital quantity is obtained; then the current value of the digital quantity is transmitted to a microprocessor, the microprocessor carries out final judgment according to a preset threshold range and the current value of the digital quantity, if the gap of the magnetic core is increased, the magnetic resistance of the corresponding part of the magnetic core is increased, so that the primary side current ip is increased, the current exceeds the range, and a fault is reported; if the magnetic core gap becomes smaller, the magnetic resistance of the corresponding part of the magnetic core becomes smaller, so that the primary side current ip becomes smaller, the current exceeds the range, and the fault is reported. The method and the device for detecting the gap of the magnetic core of the transformer can detect the gap of the magnetic core of the transformer after the transformer or a product taking the transformer as a component is assembled, have quick, simple and convenient detection process and easy implementation, and can prevent unqualified products from flowing into the market.

Drawings

Fig. 1 is a flowchart of a method for detecting a gap between cores of a transformer according to an embodiment of the present invention.

Fig. 2 is a schematic structural diagram of an EI-type magnetic core according to an embodiment of the present invention before assembly.

Fig. 3 is a schematic diagram of an assembled EI-type magnetic core according to an embodiment of the present invention.

Fig. 4 is a schematic structural diagram of an apparatus for detecting a gap between cores of a transformer according to an embodiment of the present invention in a use state.

[ reference numerals are described below ]:

e-type magnetic core-1, coil-2, I-type magnetic core-3 and magnetic core gap-4.

Detailed Description

To make the objects, advantages and features of the present invention more apparent, a method and an apparatus for detecting a gap in a core of a transformer according to the present invention will be described in detail with reference to the accompanying drawings. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is merely for the purpose of facilitating and distinctly claiming the embodiments of the present invention.

As shown in fig. 1 and 4, the present embodiment provides a method for detecting a gap of a core of a transformer, the method comprising the steps of:

s1, connecting the input end of a final assembly product containing a transformer with a working power supply, and connecting the output end of the final assembly product with a load; the voltage of the working power supply can be the rated voltage of the final assembly product during normal operation; the final assembly product to be detected is a product with a transformer as a component part, for example, the final assembly product to be detected can be a DC/DC converter;

s2, electrifying the final assembly product to work, and electrifying the transformer to operate; enabling the transformer to be electrified and operated; during actual detection, the power-on and power-off of the final assembly product can be controlled through the driving circuit and the switching device; the input end of the final assembly product is connected with the primary side of the transformer, the output end of the final assembly product is connected with the secondary side of the transformer, and when the final assembly product is powered on, the transformer in the final assembly product is powered on;

s3, acquiring the input current of the primary side of the transformer; the current of the primary side of the transformer is the current ip in fig. 4, and the current ip obtained from the circuit comprises a plurality of analog quantity current values;

s4, converting the input current into a current value; the current ip obtained from the circuit is an analog signal, the analog signal needs to be converted into a current value, one current value can also be called a digital value, namely a specific value, and the digital value is compared with a preset threshold value; when the conversion is carried out again, the average value of a plurality of analog quantity current values in a certain period can be used as a digital quantity current value;

s5, judging whether the current value is within a preset threshold range, and if so, judging that the magnetic core gap of the transformer is qualified; and if not, determining that the magnetic core gap of the transformer is unqualified. The preset threshold range is the sum of the calculated current value of the primary side of the transformer and a preset tolerance of the transformer when all parameters of the transformer are in a normal state, and the normal state comprises that the gap of the magnetic core of the transformer is normal, namely the magnetic core of the transformer is not broken, is not polluted by particles or is abnormally arranged due to factors such as installation inclination and the like.

The principle of the method for detecting the gap between the magnetic cores of the transformer provided by the embodiment is as follows: firstly, theoretical calculation is carried out according to ideal parameters of a final assembly product containing the transformer to obtain the maximum value and the minimum value of the primary side current of the transformer; then, carrying out actual detection, setting input voltage of the transformer and output load current of the transformer before the actual detection, then electrifying the transformer, enabling the transformer to work by electrifying, and detecting to obtain primary side current ip, wherein ip is im + is/N, im represents exciting current, is represents secondary side current, and N represents the turn ratio of the primary side to the secondary side; after the actual primary side current ip of the transformer is detected, the current ip in the form of analog quantity is transmitted to an A/D conversion module for analog-to-digital conversion, and a current value of digital quantity is obtained; then the current value of the digital quantity is transmitted to a microprocessor, the microprocessor carries out final judgment according to a preset threshold range and the current value of the digital quantity, if the gap of the magnetic core is increased, the magnetic resistance of the corresponding part of the magnetic core is increased, so that the primary side current ip is increased, the current exceeds the range, and a fault is reported; if the magnetic core gap becomes smaller, the magnetic resistance of the corresponding part of the magnetic core becomes smaller, so that the primary side current ip becomes smaller, the current exceeds the range, and the fault is reported.

The method for detecting the gap between the magnetic cores of the transformer can detect the gap between the magnetic cores of the transformer after the transformer or a product taking the transformer as a component is assembled, the detection process is quick and simple, the implementation is easy, and unqualified products can be prevented from flowing into the market.

Optionally, between S3 and S4, further comprising: and filtering the input current. When the transformer is a high frequency transformer, the detected current may include a high frequency interference signal, and the interference signal may be filtered by adding a filter circuit.

Optionally, after S5, the method further includes: and when the magnetic core gap of the transformer is judged to be unqualified, an alarm signal is sent out. The alarm signal can remind the detection personnel that the detected product is an unqualified product.

Optionally, the transformer is a high-frequency transformer, a medium-frequency transformer or a low-frequency transformer. The method for detecting the gap between the magnetic cores of the transformer is suitable for various types of transformers. The transformer may also be a planar transformer or a wound-wire in-line transformer.

Optionally, the magnetic core structure of the transformer is UI type, EE type, or EI type. The method for detecting the gap between the magnetic cores of the transformer is suitable for the magnetic cores in different shapes. The magnetic material can be ferrite, and the winding can be a copper wire. As shown in fig. 2 and 3, the magnetic core includes an E-type magnetic core 1, a coil 2, and an I-type magnetic core 3, and after the magnetic core is assembled, a magnetic core gap 4 may exist between the E-type magnetic core 1 and the I-type magnetic core 3.

Optionally, the transformer in the final assembly product includes a primary side and more than two secondary sides, and each secondary side corresponds to an output end of the final assembly product; the S1 specifically includes the following steps: and connecting the input end of the final assembly product with a working power supply, and respectively connecting each output end of the final assembly product with a load. The method for detecting the gap between the magnetic cores of the transformer provided by the embodiment is suitable for transformers with more than two secondary sides.

Based on the same technical concept as the above method for detecting the gap between the magnetic cores of the transformers, the present embodiment further provides an apparatus for detecting the gap between the magnetic cores of the transformers, as shown in fig. 4, the apparatus includes a current obtaining module, an a/D conversion module and a microprocessor, which are connected in series in sequence;

the current acquisition module is used for acquiring the input current of the primary side of the transformer;

the A/D conversion module is used for converting the input current into a current value;

the microprocessor is used for judging whether the current value is within a preset threshold range, and if so, judging that the magnetic core gap of the transformer is qualified; and if not, determining that the magnetic core gap of the transformer is unqualified.

The device in detection magnetic core clearance that this embodiment provided can detect the magnetic core clearance at the transformer or use the transformer to accomplish as the product equipment of component part the back, and the testing process is quick, simple and convenient, and easy to carry out can prevent unqualified product inflow market.

Optionally, as shown in fig. 4, the apparatus further includes a filter circuit, and the filter circuit is connected in series between the current obtaining module and the a/D conversion module. The interference signals can be filtered by adding a filter circuit.

Optionally, the device further comprises an alarm module, and the alarm module is connected in series with the microprocessor. When the microprocessor judges that the product is an unqualified product, the microprocessor can send a starting signal to the alarm module, and the alarm device gives an alarm after receiving the starting signal and timely reminds detection personnel.

Optionally, as shown in fig. 4, the current obtaining module is a current sensor. The current sensor can detect the current of the primary side of the transformer in real time and rapidly and transmit the current to the filter circuit or the A/D conversion module.

In summary, the method and apparatus for detecting the gap between the magnetic cores of the transformer provided by the present invention includes the following steps: s1, connecting the input end of a final assembly product containing a transformer with a working power supply, and connecting the output end of the final assembly product with a load; s2, electrifying the final assembly product to work, and electrifying the transformer to operate; s3, acquiring the input current of the primary side of the transformer; s4, converting the input electricity into a current value; s5, judging whether the current value is within a preset threshold range, and if so, judging that the magnetic core gap of the transformer is qualified; and if not, determining that the magnetic core gap of the transformer is unqualified. The device comprises a current acquisition module, an A/D conversion module and a microprocessor which are sequentially connected in series; the current acquisition module is used for acquiring the input current of the primary side of the transformer; the A/D conversion module is used for converting the input current into a current value; the microprocessor is used for judging whether the current value is within a preset threshold range, and if so, judging that the magnetic core gap of the transformer is qualified; and if not, determining that the magnetic core gap of the transformer is unqualified. The method and the device for detecting the gap of the magnetic core of the transformer can detect the gap of the magnetic core of the transformer after the transformer or a product taking the transformer as a component is assembled, have quick, simple and convenient detection process and easy implementation, and can prevent unqualified products from flowing into the market.

The above description is only for the purpose of describing the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention, and any variations and modifications made by those skilled in the art based on the above disclosure are within the scope of the present invention.