Current transformer and winding method of secondary winding of current transformer
By uniformly wrapping and connecting multiple windings on the core of the current transformer, the problem of excessive volume and low utilization in small change ratio is solved, and the DC resistance and core usage of the current transformer are reduced.
Patent Information
- Application Number
- CN202411927362.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-25
- Publication Date
- 2025-04-11
AI Technical Summary
When choosing a small change ratio, the core usage of the current transformer is large, resulting in excessive product volume. When running at no load, the electromagnetic wires are in a state of reducing utilization, resulting in waste of resources.
The first and second windings are wound evenly on the core of the current transformer until the terminal is drawn out when the set number of turns is reached. According to the variable ratio requirements, the windings are connected in parallel or in series to form a multi-lead line current transformer to reduce the DC resistance and core usage.
While ensuring that the current transformer function remains unchanged, the DC resistance of the current transformer is reduced by half, and the core usage is reduced, which reduces the cost and volume of the current transformer.
Smart Images
Figure CN119811869A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a current transformer and a winding method of a secondary winding thereof, belonging to the field of current transformers. Background Art
[0002] The current transformer is an instrument that converts the large current on the primary side into the small current on the secondary side for measurement based on the principle of electromagnetic induction. During the measurement process, different ratios are selected for the current transformer for measurement and control. However, when selecting the ratio, considering the continuous growth of the load, in order to facilitate the expansion of capacity, the current transformer is generally designed with an intermediate tap (the intermediate tap refers to a lead wire from the middle of the secondary coil of the current transformer to change the output ratio of the transformer, thereby meeting the use requirements of different circuits and measuring devices). A small ratio is selected at the beginning of a new power station; a large ratio is selected when the capacity increases. However, according to the principle of current transformer, when a small ratio is selected, the iron core of the current transformer is large, resulting in an excessively large volume of the current transformer product, and the electromagnetic wire of the second ratio is in a no-load operation state, reducing the overall utilization of the current transformer, resulting in a waste of some resources such as iron core and copper wire.
[0003] The Canadian patent application publication with application publication number CA2956287C discloses a current transformer, wherein each secondary winding has a lead wire, and each secondary winding leads out two leads. The secondary windings in the current transformer can be connected in parallel or in series. The parallel or series connection of the secondary windings is realized by their respective leads. Finally, two leads are led out from the current transformer as the leads of the current transformer, so that the additional secondary winding in the current transformer utilizes the idle space in the transformer, and the outer contour size of the current transformer does not increase, and the volume does not change, thereby obtaining a larger output energy under the same volume. Although the idle space in the current transformer is fully utilized, it is necessary to set a magnetic core used as a secondary winding in the current transformer. The addition of the newly added magnetic core not only increases the overall weight of the current transformer, but also increases the operating pressure and burden of the current transformer, and does not improve the overall utilization rate of the current transformer under different transformation ratios. Summary of the invention
[0004] The object of the present invention is to provide a current transformer and a winding method of a secondary winding thereof, so as to solve the problem that the current transformer has a large volume.
[0005] To achieve the above object, the present invention proposes a winding method for a secondary winding of a current transformer, wherein a first winding is evenly wound on an iron core according to a set number of turns, and when the coil of the first winding reaches the set number of turns, a terminal of the first winding is led out; Continue to evenly wind the second winding on the iron core according to the set number of turns until the coil of the second winding reaches the set number of turns, and then lead out the connection terminal of the second winding; The winding set number of turns of the first winding is the same as the winding set number of turns of the second winding.
[0006] Furthermore, when the current transformer is used for a small transformation ratio, the first winding and the second winding are connected in parallel through the connection terminal of the first winding and the connection terminal of the second winding, and the two terminals of the windings connected in parallel serve as connection terminals of the transformer.
[0007] Furthermore, when the current transformer is used for a large transformation ratio, the first winding and the second winding are connected in series through the connection terminal of the first winding and the connection terminal of the second winding, and the unconnected terminal of the two connection terminals after the windings are connected in series serves as the connection terminal of the transformer.
[0008] Furthermore, the second winding is wound outside the first winding.
[0009] On the other hand, the present invention also provides a current transformer, which is obtained by a winding method of the following steps: Winding the first winding evenly on the iron core according to a set number of turns, until the coil of the first winding reaches the set number of turns, and then leading out the connection terminal of the first winding; Continue to evenly wind the second winding on the iron core according to the set number of turns until the coil of the second winding reaches the set number of turns, and then lead out the connection terminal of the second winding; The winding set number of turns of the first winding is the same as the winding set number of turns of the second winding.
[0010] Furthermore, when the current transformer is used for a small transformation ratio, the first winding and the second winding are connected in parallel through the connection terminal of the first winding and the connection terminal of the second winding, and the two terminals of the windings connected in parallel serve as connection terminals of the transformer.
[0011] Furthermore, when the current transformer is used for a large transformation ratio, the first winding and the second winding are connected in series through the connection terminal of the first winding and the connection terminal of the second winding, and the unconnected terminal of the two connection terminals after the windings are connected in series serves as the connection terminal of the transformer.
[0012] Furthermore, the second winding is wound outside the first winding.
[0013] The beneficial effects of the present invention are as follows: the first winding is evenly wound on the iron core according to the set number of turns, and the connection terminal of the first winding is led out when the coil of the first winding reaches the set number of turns; the second winding is evenly wound on the iron core according to the set number of turns, and the connection terminal of the second winding is led out when the coil of the second winding reaches the set number of turns; the set number of turns of the first winding is the same as the set number of turns of the second winding, so that multiple connection terminals are designed in the current transformer, and the DC resistance of the current transformer is reduced by half while the function of the current transformer remains unchanged, so as to achieve the purpose of reducing the amount of iron core used and reducing the cost of the current transformer. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 It is a structural schematic diagram of a winding method for a secondary winding of a current transformer in one aspect of the present invention after winding an electromagnetic transformer in an actual application scenario. DETAILED DESCRIPTION
[0015] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.
[0016] The inventive concept of the present invention is to wind the first winding and the second winding in the current transformer respectively to form a multi-lead current transformer with the first winding terminal and the second winding terminal, so as to adjust the lead wires of the current transformer and achieve the reduction of the DC resistance of the current transformer by half while ensuring that the function of the current transformer remains unchanged.
[0017] Method Example 1: One aspect of the present invention provides a winding method for a secondary winding of a current transformer, wherein a first winding is evenly wound on an iron core according to a set number of turns, and a connection terminal of the first winding is led out until the coil of the first winding reaches the set number of turns; here, the set number of turns can be set according to different transformation ratio requirements.
[0018] Continue to evenly wind the second winding on the iron core according to the set number of turns until the coil of the second winding reaches the set number of turns, and then lead out the connection terminal of the second winding; here, the set number of turns of the first winding is the same as the set number of turns of the second winding.
[0019] In a preferred embodiment of the present invention, Figure 1, which is a structural schematic diagram of a current transformer secondary winding winding method according to one aspect of the present invention after the electromagnetic transformer is wound in an actual application scenario, wherein the first winding is evenly wound on the iron core A according to a set number of turns, and when the coil of the first winding reaches the set number of turns, the connection terminals of the first winding, i.e., S1 and S2`, are led out; the second winding continues to be evenly wound on the iron core A according to the set number of turns, and when the coil of the second winding reaches the set number of turns, the connection terminals of the second winding, i.e., S2 and S3, are led out.
[0020] Method Example 2: Following the above-mentioned embodiment of the present invention, when the current transformer is used for a small transformation ratio, the first winding and the second winding are connected in parallel through the connection terminal of the first winding and the connection terminal of the second winding, and the two terminals after the windings are connected in parallel serve as the connection terminals of the transformer, thereby achieving the purpose of reducing the DC resistance in the current transformer by half.
[0021] Furthermore, when the current transformer is used for a large transformation ratio, the first winding and the second winding are connected in series through the connection terminal of the first winding and the connection terminal of the second winding, and the unconnected terminal of the two connection terminals of the windings in series serves as the connection terminal of the transformer.
[0022] For example, the first winding and the second winding are wound on the core A of the current transformer according to a set number of turns to form the connection terminals S1 and S2' of the first winding, and the connection terminals S2 and S3 of the second winding; when the current transformer is used for a small transformation ratio, S1 and S2 are connected, and S2' is connected with S3 to realize the parallel connection between the first winding and the second winding, and the two terminals after the windings are connected in parallel are used as the connection terminals of the transformer; when the current transformer is used for a large transformation ratio, S2 and S2' are connected to realize the series connection between the first winding and the second winding, and the unconnected terminal of the two connection terminals after the windings are connected in series is used as the connection terminal of the transformer.
[0023] Method embodiment 3: In the actual application scenario of the present invention, the current transformer is disconnected from the middle tap position, and two lead wires are led out respectively. Together with the coil winding head end and the coil winding tail end in the current transformer, a total of four lead wires are designed. When the current transformer is used for a small transformation ratio, the second winding is connected in parallel with the first winding; when a large transformation ratio is used, the second winding is connected in series with the second winding to achieve the purpose of halving the DC resistance of the current transformer, and by proposing to increase the tap lead wire, when using different transformation ratios, the current transformer transformation ratio is adjusted by adjusting the wiring method of the external tap lead wire, while reducing the internal resistance of the first transformation ratio itself and reducing the product volume.
[0024] Current transformer embodiment: The present invention further provides a current transformer, which is obtained by the above-mentioned winding method of the secondary winding of the current transformer. The introduction of the above-mentioned method has been clearly described in the embodiments and will not be repeated here.
Claims
1. A winding method for a secondary winding of a current transformer, characterized in that: Winding the first winding evenly on the iron core according to a set number of turns, until the coil of the first winding reaches the set number of turns, and then leading out the connection terminal of the first winding; Continue to evenly wind the second winding on the iron core according to the set number of turns until the coil of the second winding reaches the set number of turns, and then lead out the connection terminal of the second winding; The winding set number of turns of the first winding is the same as the winding set number of turns of the second winding.
2. The winding method of the secondary winding of the current transformer according to claim 1, characterized in that: When the current transformer is used for a small transformation ratio, the first winding and the second winding are connected in parallel through the connection terminal of the first winding and the connection terminal of the second winding, and the two terminals of the parallel-connected windings serve as connection terminals of the transformer.
3. The winding method of the secondary winding of the current transformer according to claim 1, characterized in that: When the current transformer is used for a large transformation ratio, the first winding and the second winding are connected in series through the connection terminal of the first winding and the connection terminal of the second winding, and the unconnected terminal of the two connection terminals of the windings in series serves as the connection terminal of the transformer.
4. The winding method of the secondary winding of a current transformer according to claim 1, characterized in that: The second winding is wound outside the first winding.
5. A current transformer, characterized in that: Obtained by the winding method of the following steps: Winding the first winding evenly on the iron core according to a set number of turns, until the coil of the first winding reaches the set number of turns, and then leading out the connection terminal of the first winding; Continue to evenly wind the second winding on the iron core according to the set number of turns until the coil of the second winding reaches the set number of turns, and then lead out the connection terminal of the second winding; The winding set number of turns of the first winding is the same as the winding set number of turns of the second winding.
6. The current transformer according to claim 5, characterized in that: When the current transformer is used for a small transformation ratio, the first winding and the second winding are connected in parallel through the connection terminal of the first winding and the connection terminal of the second winding, and the two terminals of the parallel-connected windings serve as connection terminals of the transformer.
7. The current transformer according to claim 5, characterized in that: When the current transformer is used for a large transformation ratio, the first winding and the second winding are connected in series through the connection terminal of the first winding and the connection terminal of the second winding, and the unconnected terminal of the two connection terminals of the windings in series serves as the connection terminal of the transformer.
8. The current transformer according to claim 5, characterized in that: The second winding is wound outside the first winding.