Calibratable electricity metering and leakage protection integrated mutual inductor

Abstract

The utility model relates to the technical field of mutual inductors, in particular to a calibratable electricity metering and leakage protection integrated mutual inductor which comprises a first mutual inductor and a second mutual inductor which are arranged in a stacked mode, and a calibration coil used for calibration self-inspection and a detection coil used for detecting leakage current are arranged in the first mutual inductor. A first U-shaped rod and a second U-shaped rod are arranged in parallel, a single arm of the first U-shaped rod penetrates through the inner ring of the first mutual inductor, the end of the first U-shaped rod extends out of the first mutual inductor, a single arm of the second U-shaped rod penetrates through the inner ring of the first mutual inductor and the inner ring of the second mutual inductor, and the end of the second U-shaped rod extends out of the first mutual inductor. According to the utility model, the two mutual inductors are integrally designed, so that the occupied space of a product is reduced, and miniaturization development is facilitated; the calibration coil is additionally arranged in the mutual inductor, so that calibration and self-inspection of the mutual inductor are facilitated, the mutual inductor has higher safety performance, assembly is simple and convenient, and automatic production can be achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of transformers, and particularly relates to a calibratable integrated transformer for electricity metering and leakage protection. Background Art

[0002] Transformers are widely used in various electrical equipment and facilities, mainly for functions such as electricity metering, leakage detection, and leakage protection. With the rapid development of the electric vehicle industry, new opportunities and challenges have been brought to the development of transformers. Currently, the transformers for electricity metering and leakage protection are two types of transformer products, and in the market, the metering transformer and the leakage protection transformer are used separately. Assembling multiple transformers will result in a large area and space occupied on the circuit board, which is not conducive to the miniaturization of devices.

[0003] With the continuous update and iteration of technology, some design schemes of integrated transformers for electricity metering and leakage protection have emerged one after another. However, due to the increasingly complex electromagnetic environment and signals in current electrical equipment, during use, under various electromagnetic fields and stray interference signals in the circuit, the electricity metering accuracy and leakage detection accuracy of the transformer will inevitably be affected and decreased, resulting in a decline in the safety and reliability level of power supply and charging equipment. In the prior art, in view of the complex application environment of the above-mentioned leakage protection transformer, it is particularly important to perform regular self-check and calibration on the leakage protection transformer. Content of the Utility Model

[0004] The purpose of the utility model is to provide a calibratable integrated transformer for electricity metering and leakage protection to solve the above technical problems;

[0005] The technical problems solved by the utility model can be realized by adopting the following technical solutions:

[0006] A calibratable integrated transformer for electricity metering and leakage protection includes:

[0007] A first transformer and a second transformer stacked, and a calibration coil for calibration self-check and a detection coil for detecting leakage current are respectively arranged in the first transformer;

[0008] A first U-shaped bar and a second U-shaped bar arranged in parallel, a single arm of the first U-shaped bar penetrates through the inner ring of the first transformer and the end extends out of the first transformer, and a single arm of the second U-shaped bar penetrates through the inner ring of the first transformer and the inner ring of the second transformer and the end extends out of the first transformer.

[0009] Preferably, the first transformer includes:

[0010] A first housing, a first middle column is arranged in the first housing, and a first pin slot is arranged on the side surface of the first housing;

[0011] The first winding coil is disposed within the first housing and sleeved on the first central column;

[0012] The first insulating colloid is filled within the first housing and wraps around the circumferential side of the first winding coil.

[0013] Preferably, the first winding coil includes,

[0014] A first annular magnetic core;

[0015] The calibration coil wound around the first annular magnetic core;

[0016] The detection coils wound around the first annular magnetic core and located on both sides of the calibration coil;

[0017] The ends of the detection coils and the ends of the calibration coil are respectively connected to first pins, and the first pins are inserted into the first pin slots.

[0018] Preferably, two vertically penetrating assembly holes are respectively and parallelly provided on the outer edge of the first housing and on the first central column. At least one groove is further provided at the bottom of the first housing, and both ends of the groove are communicated with the assembly holes; the bottom of the first U-shaped bar is located within the groove, and both the first U-shaped bar and the second U-shaped bar penetrate through the assembly holes and their ends extend out from the assembly holes.

[0019] Preferably, an electromagnetic shielding shell is provided on the circumferential side of the first winding coil. The electromagnetic shielding shell includes an annular shielding cover and an annular shielding lid. An opening is provided on the side surface of the annular shielding cover, and a high-temperature tape is pasted at the opening of the annular shielding cover.

[0020] Preferably, the second mutual inductor includes,

[0021] A second housing, a second central column is provided within the second housing, and a second pin slot is provided on the side surface of the second housing;

[0022] A second winding coil is disposed within the second housing and sleeved on the second central column;

[0023] A second insulating colloid is filled within the second housing and wraps around the circumferential side of the second winding coil.

[0024] Preferably, the second central column is provided with a first groove body, a second groove body is provided on the side of the second housing opposite to the first groove body, and a receiving portion is further provided on the inner side of the bottom of the second housing, and the receiving portion extends out of the bottom of the second housing; the second U-shaped bar is assembled within the communication space of the receiving portion, the first groove body, and the second groove body.

[0025] Preferably, the second winding coil includes,

[0026] Second annular magnetic core;

[0027] A second coil wound around the second annular magnetic core, with the ends of the second coil respectively connected to second pins, and the second pins are inserted into the second pin slots.

[0028] Preferably, a pin hole that penetrates up and down and can pass through the second pin is provided on the first housing.

[0029] Preferably, a plurality of slots are provided on the outer sides of the first current transformer and the second current transformer, and insulating partitions are inserted into the slots.

[0030] Advantages of the present utility model: Due to the adoption of the above technical solutions, the present utility model integrates two current transformers, reducing the occupied space of the product and facilitating miniaturization development; a calibration coil is added inside the current transformer to facilitate the calibration and self-check of the current transformer, making it have higher safety performance, simple and convenient assembly, and capable of realizing automated production. Description of the Drawings

[0031] Figure 1 It is a schematic diagram of the overall structure of the integrated current metering and leakage protection current transformer in the embodiment of the present utility model;

[0032] Figure 2 It is an exploded view of the structure of the integrated current metering and leakage protection current transformer in the embodiment of the present utility model;

[0033] Figure 3 It is a schematic diagram of the structure of the first current transformer in the embodiment of the present utility model;

[0034] Figure 4 It is a schematic diagram of the structure of the first housing in the embodiment of the present utility model;

[0035] Figure 5 It is a schematic diagram of the bottom structure of the first housing in the embodiment of the present utility model;

[0036] Figure 6 It is a schematic diagram of the structure of the second current transformer in the embodiment of the present utility model;

[0037] Figure 7 It is a schematic diagram of the structure of the second housing in the embodiment of the present utility model.

[0038] In the attached drawings: 1. First transformer; 11. First U-shaped bar; 12. First housing; 121. First middle column; 122. First pin slot; 123. Assembly hole; 124. Groove; 125. Pin hole; 13. First winding coil; 131. First toroidal core; 132. Detection coil; 133. First pin; 134. Calibration coil; 14. First insulating colloid; 15. Slot; 16. Insulating partition; 17. Electromagnetic shielding case; 171. Ring-shaped shielding cover; 172. Ring-shaped shielding hood; 2. Second transformer; 21. Second U-shaped bar; 22. Second housing; 221. Second middle column; 222. Second pin slot; 223. First slot; 224. Second slot; 225. Accommodating part; 23. Second winding coil; 231. Second toroidal core; 232. Second coil; 233. Second pin; 24. Second insulating colloid. Detailed implementation mode

[0039] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0040] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0041] Next, the present invention will be further described in conjunction with the accompanying drawings and specific embodiments, but it is not limited to the present invention.

[0042] A calibratable integrated transformer for electricity metering and leakage protection, as Figures 1 to 7 shown, includes

[0043] The first transformer 1 and the second transformer 2 are stacked, and the first transformer 1 is internally provided with a calibration coil 134 for calibration self-checking and a detection coil 132 for detecting leakage current.

[0044] The first U-shaped bar 11 and the second U-shaped bar 21 are arranged in parallel. The single arm of the first U-shaped bar 11 penetrates through the inner ring of the first transformer 1 and the end extends out of the first transformer 1. The single arm of the second U-shaped bar 21 penetrates through the inner ring of the first transformer 1 and the inner ring of the second transformer 2 and the end extends out of the first transformer 1.

[0045] Specifically, the present utility model mainly includes a first mutual inductor 1, a second mutual inductor 2, a first U-shaped rod 11 and a second U-shaped rod 21. The first mutual inductor 1 and the second mutual inductor 2 are stacked. The first U-shaped rod 11 passes through the first mutual inductor 1, and the second U-shaped rod 21 is placed inside the second mutual inductor 2, and both ends of the second U-shaped rod 21 pass through the first mutual inductor 1; a calibration coil 134 and a detection coil 132 are provided inside the first mutual inductor 1.

[0046] More specifically, as Figure 1 , Figure 2 shown, the first mutual inductor 1 and the second mutual inductor 2 are stacked vertically. The first U-shaped rod 11 passes through the first mutual inductor 1 from bottom to top and serves as the primary side port of the first mutual inductor 1; the U-shaped end of the second U-shaped rod 21 is arranged inside the second mutual inductor 2, and its two ends pass through the first mutual inductor 1 from bottom to top. The length of the second U-shaped rod 21 is not less than the sum of the heights of the first mutual inductor 1 and the second mutual inductor 2 so as to be able to pass out of the first mutual inductor 1 and serve as the primary side port of the second mutual inductor 2; the first mutual inductor 1 is a leakage mutual inductor, and at least one group of detection coils 132 are provided inside it, which are mainly used to detect the leakage current in the actual circuit. In this embodiment, a group of calibration coils 134 are additionally provided inside the first mutual inductor 1. After the mutual inductor is assembled, an analog leakage current can be applied externally and the leakage mutual inductor can be calibrated and self-tested through the calibration coil 134 to ensure the safety and reliability of the mutual inductor. In actual applications, calibration is often carried out by winding several turns of coils outside the mutual inductor, and the coils need to be removed later, and the operation is relatively complicated. In this solution, the calibration coil 134 is directly arranged inside the mutual inductor, making the calibration and self-test of the mutual inductor more convenient.

[0047] The present utility model integrates the two mutual inductors. Compared with the existing method of installing the mutual inductors in different areas of the main board respectively, it can greatly reduce the occupied space of the product and is conducive to miniaturization development; and a calibration coil 134 is additionally provided inside the mutual inductor, which is convenient for the calibration and self-test of the mutual inductor and enables it to have higher safety performance.

[0048] In a preferred embodiment, as Figures 2 to 5 shown, the first mutual inductor 1 includes,

[0049] a first housing 12, a first middle column 121 is provided inside the first housing 12, and a first pin slot 122 is provided on the side of the first housing 12;

[0050] a first winding coil 13, which is arranged inside the first housing 12 and sleeved on the first middle column 121;

[0051] a first insulating colloid 14, which is filled inside the first housing 12 and covers the periphery of the first winding coil 13.

[0052] In a preferred embodiment, the first winding coil 13 includes,

[0053] a first toroidal core 131;

[0054] a calibration coil 134 wound around the first toroidal core 131;

[0055] detection coils 132 wound around the first toroidal core 131 and located on both sides of the calibration coil 134;

[0056] The ends of the detection coils 132 and the ends of the calibration coil 134 are respectively connected to a first pin 133, and the first pin 133 is inserted into the first pin slot 122.

[0057] Specifically, the first mutual inductor 1 is a leakage current mutual inductor for detecting the leakage current in the main circuit. It has three independent coils wound around the first toroidal core 131, including two detection coils 132 and one calibration coil 134. The two detection coils 132 are arranged oppositely and are jointly used to detect the leakage current in the actual circuit. The calibration coil 134 is arranged between the detection coils 132 and is usually wound only a few turns. It is used for calibration and self-check by simulating the leakage current after the mutual inductor is assembled to ensure the good performance of the mutual inductor. The two ends of each detection coil 132 and the calibration coil 134 are welded to a first pin 133. That is, the first mutual inductor 1 has a total of 6 first pins 133. Correspondingly, 6 first pin slots 122 for placing the first pins 133 are provided on the side wall of the first housing 12. The first pin 133 is the secondary side port of the first mutual inductor 1 and together with the first U-shaped bar 11 constitutes the detection port of the first mutual inductor 1.

[0058] The first winding coil 13 is sleeved on the first middle column 121 inside the first housing 12. The first pins 133 are inserted into the corresponding first pin slots 122. Then, the first insulating colloid 14 is potted inside the first housing 12. After the first insulating colloid 14 is completely cured, the first U-shaped bar 11 is inserted, and finally the first mutual inductor 1 is obtained.

[0059] In a preferred embodiment, two vertically penetrating assembly holes 123 are respectively and parallelly provided on the outer edge and the first middle column 121 of the first housing 12. At least one groove 124 is further provided at the bottom of the first housing 12. The two ends of the groove 124 are communicated with the assembly holes 123. The bottom of the first U-shaped bar 11 is located in the groove 124. Both the first U-shaped bar 11 and the second U-shaped bar 21 penetrate through the assembly holes 123 and their ends extend out from the assembly holes 123.

[0060] Specifically, there are 2 assembly holes 123 provided on the outer side wall of the first housing 12 and the first middle column 121. The assembly holes 123 located on the same side of the first housing 12 and the first middle column 121 form a group, and there are two groups in total, which are respectively used to assemble the first U-shaped rod 11 and the second U-shaped rod 21.

[0061] More specifically, the straight arm ends of the first U-shaped rod 11 and the second U-shaped rod 21 can be set in any shape such as circular, rectangular, polygonal, etc., and the shape of the corresponding assembly hole 123 is matched according to the shape of the U-shaped rod.

[0062] In a preferred embodiment, an electromagnetic shielding case 17 is provided on the peripheral side of the first winding coil 13. The electromagnetic shielding case 17 includes an annular shielding cover 172 and an annular shielding lid 171. The side of the annular shielding cover 172 is provided with an opening, and a high-temperature tape is attached to the opening of the annular shielding cover 172.

[0063] Specifically, in this embodiment, an electromagnetic shielding case 17 is provided on the peripheral side of the first winding coil 13. The electromagnetic shielding case 17 includes an annular shielding cover 172 and an annular shielding lid 171. The first winding coil 13 is installed inside the annular shielding cover 172 and the annular shielding lid 171. An opening is provided on the side of the annular shielding cover 172 to facilitate the coil ends of the first winding coil 13 to be led out of the electromagnetic shielding case 17.

[0064] The electromagnetic shielding case 17 can protect the first mutual inductor 1 from external factors such as external electric fields or magnetic fields. The inside of the electromagnetic shielding case 17 can be sprayed with an insulating coating to make it have a more reliable insulating function; after the first winding coil 13 is installed in the electromagnetic shielding case 17, its coil ends are led out from the opening and a high-temperature tape is pasted at the opening. The high-temperature tape is respectively attached to the side of the annular shielding cover 172 and the upper surface of the annular shielding lid 171, which can further improve the shielding effect of the electromagnetic shielding case 17 and at the same time prevent the annular shielding lid 171 from shifting.

[0065] In a preferred embodiment, as Figure 2 , Figure 6 , Figure 7 shown, the second mutual inductor 2 includes,

[0066] A second housing 22, with a second middle column 221 provided inside the second housing 22, and a second pin slot 222 provided on the side of the second housing 22;

[0067] A second winding coil 23, which is arranged inside the second housing 22 and sleeved on the second middle column 221;

[0068] A second insulating colloid 24, which is filled inside the second housing 22 and covers the peripheral side of the second winding coil 23.

[0069] In a preferred embodiment, the second central column 221 is provided with a first groove 223. A second groove 224 is provided on the side of the second housing 22 opposite to the first groove 223. An accommodating portion 225 is further provided on the inner side of the bottom of the second housing 22. The accommodating portion 225 extends out of the bottom of the second housing 22. The second U-shaped rod 21 is assembled in the communication space between the accommodating portion 225, the first groove 223 and the second groove 224.

[0070] Specifically, the second central column 221 is provided with a first groove 223. The peripheral area of the first groove 223 is used for assembling the second winding coil 23. From the perspective of the superposition of the upper and lower transformers, the axes of the first winding coil 13 and the second winding coil 23 are spaced apart by a certain distance, so that there is enough space for the integrated transformer to simultaneously arrange the first U-shaped rod 11 and the second U-shaped rod 21. Second grooves 224 are symmetrically provided on the side surface of the second housing 22 on the opposite side of the first groove 223. The distance between the first groove 223 and the second groove 224 is the same as the distance between the two ends of the second U-shaped rod 21. An accommodating portion 225 is further provided on the inner side of the bottom of the second housing 22. The accommodating portion 225 extends out of the bottom of the second housing 22, and the outward extension dimension is not less than the thickness of the lower end of the second U-shaped rod 21. The accommodating portion 225 communicates with both the first groove 223 and the second groove 224, and is jointly used for assembling the second U-shaped rod 21.

[0071] In a preferred embodiment, the second winding coil 23 includes,

[0072] a second toroidal magnetic core 231;

[0073] a second coil 232 wound around the second toroidal magnetic core 231. The ends of the second coil 232 are respectively connected to second pins 233, and the second pins 233 are inserted into the second pin slots 222.

[0074] Specifically, the second transformer 2 is a current transformer for measuring the current value flowing through the main circuit. A set of second coils 232 is wound around the second toroidal core 231. Two ends of each second coil 232 are welded with a second pin 233. That is, the second transformer 2 has a total of 2 first pins 133. Correspondingly, 2 second pin slots 222 for placing the second pins 233 are provided on the side wall of the second housing 22. The second pins 233 are the secondary side ports of the second transformer 2 and together with the second U-shaped bar 21 form the detection port of the second transformer 2. The second U-shaped bar 21 is inserted into the groove body and the accommodating part 225. Then, the second winding coil 23 is sleeved on the second middle column 221 inside the second housing 22, and the second pins 233 are inserted into the corresponding second pin slots 222. Subsequently, the second insulating colloid 24 is potted inside the second housing 22, and finally the second transformer 2 is obtained. The second U-shaped bar 21 of the second transformer 2 is inserted into the assembly hole 123 of the first transformer 1, and finally the integrated transformer for electricity metering and leakage protection is obtained.

[0075] In a preferred embodiment, the first housing 12 is provided with a pin hole 125 that penetrates up and down and can penetrate the second pin 233.

[0076] In a preferred embodiment, a plurality of slots 15 are provided on the outer sides of the first transformer 1 and the second transformer 2, and insulating partitions 16 are inserted into the slots 15.

[0077] Specifically, at least a part of the first U-shaped bar 11, the second U-shaped bar 21, the first pin 133, and the second pin 233 is located outside the first insulating colloid 14; a plurality of slots 15 are further provided between the parts of the first U-shaped bar 11, the second U-shaped bar 21, the first pin 133, and the second pin 233 located outside the first insulating colloid 14, and insulating partitions 16 are inserted into the slots 15.

[0078] In the present utility model, the first housing 12 is provided with 2 pin holes 125 that penetrate up and down, and the positions correspond to the second pins 233 of the second transformer 2. The second pins 233 can penetrate into the pin holes 125 from bottom to top, so that the test ends of the first pins 133, the second pins 233, the first U-shaped bar 11, and the second U-shaped bar 21 are all led out from the upper end of the first transformer 1.

[0079] More specifically, in this embodiment, insulating partitions 16 are provided between the first pin 133, the second pin 233, the first U-shaped bar 11, and the second U-shaped bar 21. Since the individual transformers are small and the distance between the U-shaped bar and the pin is very close, arc and other adverse phenomena are likely to occur. The setting of the insulating partitions 16 can effectively avoid this situation.

[0080] The above are only the preferred embodiments of the present utility model, and thus do not limit the implementation manners and protection scope of the present utility model. For those skilled in the art, it should be realized that all the solutions obtained by equivalent substitutions and obvious changes made by using the specification and illustrated content of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A calibrable integrated current meter and leakage protection transformer, characterized in that: include, A first mutual inductor (1) and a second mutual inductor (2) are stacked, wherein the first mutual inductor (1) is provided with a calibration coil (134) for calibration self-test and a detection coil (132) for detecting leakage current; A first U-shaped rod (11) and a second U-shaped rod (21) are arranged in parallel, wherein a single arm of the first U-shaped rod (11) passes through the inner ring of the first mutual inductor (1) and an end portion thereof extends outside the first mutual inductor (1), and a single arm of the second U-shaped rod (21) passes through the inner ring of the first mutual inductor (1) and the inner ring of the second mutual inductor (2) and an end portion thereof extends outside the first mutual inductor (1).

2. The calibrable integrated current meter and leakage protection transformer according to claim 1 is characterized in that: The first mutual inductor (1) comprises: A first shell (12), wherein a first center column (121) is provided inside the first shell (12), and a first pin groove (122) is provided on a side surface of the first shell (12); A first winding coil (13) is disposed in the first housing (12) and sleeved on the first center column (121); A first insulating colloid (14) is filled in the first shell (12) and covers the circumference of the first winding coil (13).

3. The calibrable integrated current meter and leakage protection transformer according to claim 2 is characterized in that: The first winding coil (13) comprises: A first annular magnetic core (131); The calibration coil (134) is wound on the first annular magnetic core (131); a detection coil (132) wound on the first annular magnetic core (131) and located on both sides of the calibration coil (134); The end of the detection coil (132) and the end of the calibration coil (134) are respectively connected to a first pin (133), and the first pin (133) is inserted into the first pin slot (122).

4. The calibrable integrated current meter and leakage protection transformer according to claim 2 is characterized in that: Two vertically penetrating assembly holes (123) are respectively provided in parallel on the outer edge of the first shell (12) and the first center column (121); at least one groove (124) is also provided at the bottom of the first shell (12), and both ends of the groove (124) are connected to the assembly hole (123); the bottom of the first U-shaped rod (11) is located in the groove (124), and the first U-shaped rod (11) and the second U-shaped rod (21) both pass through the assembly hole (123) and their ends both extend out of the assembly hole (123).

5. The calibrable integrated current meter and leakage protection transformer according to claim 2, characterized in that: An electromagnetic shielding shell (17) is provided on the circumferential side of the first winding coil (13), the electromagnetic shielding shell (17) comprising an annular shielding cover (172) and an annular shielding lid (171), an opening is provided on the side of the annular shielding cover (172), and a high-temperature adhesive tape is applied to the opening of the annular shielding cover (172).

6. The calibrable integrated current meter and leakage protection transformer according to claim 2, characterized in that: The second mutual inductor (2) comprises: A second shell (22), wherein a second center column (221) is provided inside the second shell (22), and a second pin groove (222) is provided on a side surface of the second shell (22); A second winding coil (23) is disposed in the second housing (22) and sleeved on the second center column (221); The second insulating colloid (24) is filled in the second shell (22) and covers the circumference of the second winding coil (23).

7. The calibrable integrated current meter and leakage protection transformer according to claim 6, characterized in that: A first slot body (223) is provided on the second center column (221); a second slot body (224) is provided on the side of the second shell (22) opposite to the first slot body (223); a receiving portion (225) is also provided on the inner side of the bottom of the second shell (22); the receiving portion (225) extends outward from the bottom of the second shell (22); the second U-shaped rod (21) is assembled in the connecting space between the receiving portion (225) and the first slot body (223) and the second slot body (224).

8. The calibrable integrated current meter and leakage protection transformer according to claim 6, characterized in that: The second winding coil (23) comprises: A second annular magnetic core (231); A second coil (232) is wound on the second annular magnetic core (231), and ends of the second coil (232) are respectively connected to second pins (233), and the second pins (233) are inserted into the second pin slots (222).

9. The calibrable integrated current meter and leakage protection transformer according to claim 8, characterized in that: The first shell (12) is provided with a pin hole (125) which passes through from top to bottom and through which the second pin (233) can be inserted.

10. The calibrable integrated current meter and leakage protection transformer according to claim 1, characterized in that: A plurality of slots (15) are provided on the outer side of the first mutual inductor (1), and insulating partitions (16) are inserted into the slots (15).

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