CN112526280A

CN112526280A - Annular opening PCB Rogowski coil of sectional type wiring

Info

Publication number: CN112526280A
Application number: CN201910887871.2A
Authority: CN
Inventors: 张建良; 李金鳌
Original assignee: Beijing Inhand Network Technology Co ltd
Current assignee: Beijing Inhand Network Technology Co ltd
Priority date: 2019-09-19
Filing date: 2019-09-19
Publication date: 2021-03-19

Abstract

The invention discloses an annular opening PCB Rogowski coil with sectional wiring, which is characterized in that the opening PCB Rogowski coil comprises a first semicircular PCB block and a second semicircular PCB block, and the first semicircular PCB block and the second semicircular PCB block are spliced to form a complete annular PCB Rogowski coil; the first semicircular PCB block and the second semicircular PCB block are both provided with wires on the front side and the back side at the same time, a plurality of turn winding parts and a plurality of turn lacking parts are arranged during wiring, and the turn winding parts and the turn lacking parts are arranged at intervals; and the number of turns of the coil in each turn part is the same, the central angles corresponding to the wiring areas of all the turn parts are the same, and the central angles corresponding to the distribution areas of all the turn-lacking parts are the same.

Description

Annular opening PCB Rogowski coil of sectional type wiring

Technical Field

The invention relates to the technical field of accurate current measurement for power transmission lines, in particular to an open PCB Rogowski coil with sectional wiring.

Background

The fault transient current traveling wave of the power transmission line contains a large amount of fault information, and is the basis of fault diagnosis of the power transmission line. Rogowski Coil (Rogowski Coil) is a Coil formed by uniformly winding a wire around a frame of a non-magnetic material having a uniform cross section. Rogowski coils have been commonly used in current measuring devices because of their light weight, wide frequency band, good linearity, and no magnetic saturation. The Rogowski coil has higher measurement current precision and large measurement signal bandwidth, can realize electrical isolation measurement with lower cost, has almost infinite current tolerance capability, is suitable for accurate measurement of current of a current-carrying conductor with a fixed position, and can be applied to the fields of relay protection and the like.

In order to adapt to the detection of the power transmission line, the rogowski coil in the prior art can adopt a PCB opening rogowski coil. For example, the PCB rogowski coil shown in CN104407200A, which uses a computer aided wiring design technology, can uniformly lay printed circuits on the PCB, thereby further improving the measurement accuracy and sensitivity of the rogowski coil. Meanwhile, in order to facilitate the installation of the fault detection device with the PCB opening Rogowski coil on a power transmission line, the PCB Rogowski coil is arranged into two semicircular PCB parts which are butted to form a complete annular PCB Rogowski coil, the structure can realize that the power transmission line is easily placed at the circle center position of the PCB Rogowski coil, but the annular PCB Rogowski coil is divided into the two semicircular parts, and the wiring in the connection area of the two semicircular parts cannot realize the same wiring density as that of other parts, so that when the power transmission cable is not positioned at the circle center position to generate an eccentric condition, the measurement precision can be seriously influenced. Therefore, a technical scheme for improving the measurement accuracy of the open-ended PCB rogowski coil is needed in the art, and the measurement accuracy can be ensured when the measured cable is positioned in the PCB rogowski coil and deviates from the center.

Disclosure of Invention

One of the technical problems to be solved by the invention is to improve the measurement precision of the current when the measured cable deviates from the center of the Rogowski coil of the PCB.

In order to solve the technical problem, the invention provides a PCB opening Rogowski coil, which comprises a first semicircular PCB block and a second semicircular PCB block, wherein the first semicircular PCB block and the second semicircular PCB block are spliced to form a complete annular PCB Rogowski coil;

the first semicircular PCB block and the second semicircular PCB block are both provided with wires on the front side and the back side at the same time, a plurality of turn winding parts and a plurality of turn lacking parts are arranged during wiring, and the turn winding parts and the turn lacking parts are arranged at intervals;

and the number of turns of the coil in each turn part is the same, the central angles corresponding to the wiring areas of all the turn parts are the same, and the central angles corresponding to the distribution areas of all the turn-lacking parts are the same.

In one embodiment, the open Rogowski coil of the PCB comprises two windings of a forward winding and a reverse winding, wherein each turn of the forward winding comprises a forward winding inlet wire, the forward winding inlet wire is routed to a forward winding near-end via hole on the back of the PCB after passing through a forward winding far-end via hole, and the wire is routed to a forward winding outlet wire on the front after passing through a forward winding near-end via hole;

the outgoing line of each forward winding is connected with the incoming line of the next forward winding, and the incoming line of the first forward winding of each turn part is arranged along the circumference of the open Rogowski coil of the PCB in the turn-missing part.

In one embodiment, each turn of reverse winding comprises a reverse winding inlet wire, the reverse winding inlet wire passes through the reverse winding near-end via hole after being routed on the back surface of the PCB, passes through the reverse winding near-end via hole, is routed on the front surface of the PCB to the reverse winding far-end via hole, and then passes through the reverse winding far-end via hole to be connected to the reverse winding outlet wire;

the outgoing line of each reverse winding is connected with the incoming line of the next reverse winding, and the outgoing line of the last reverse winding of each winding part is arranged along the circumference of the open Rogowski coil in the missing winding part.

In one embodiment, eight winding turn portions are uniformly distributed on the circumference of the open rogowski coil of the PCB, each winding turn portion corresponds to a central angle of 33 °, and each missing turn portion corresponds to a central angle of 12 °.

In one embodiment, 12 windings are arranged in each turn portion, and the central angle interval between each winding is 3 °.

The principle of the invention for dividing the turns into several components is as follows, as shown in fig. 1, if the distance of the cable from the center of the rogowski coil is d, according to the geometrical relationship:

R²＝(rcosα)²+(rsinα+d)²

β＝γ

the Rogowski coil at the point A induces an electromotive force

The induced electromotive force of the whole Rogowski coil is as follows:

wherein:

u₀is a vacuum magnetic conductivity; and S is the micro area of the closed curved surface.

The above formula can be simplified into

If there are segments in the coil, N is the number of segments

θ_i1，θ_i2The starting and ending angles of each segment of wire turns.

Based on the simulation result of the formula, the influence of the eccentric distance d on the output value precision of the Rogowski coil can be effectively reduced by dividing the coil into a plurality of sections.

Compared with the prior art, the invention has the following advantages: the winding of the PCB Rogowski coil adopts sectional layout, the winding comprises a winding part and a missing part, the winding part is uniformly distributed on the circumference of the spiral coil, the central angles corresponding to the winding part and the missing part are consistent, and the opening of the PCB Rogowski coil is arranged at the missing part. The arrangement mode ensures that when the cable deviates the circle center in the Rogowski coil of the PCB, the current measurement precision is not influenced, and the influence on the current precision is effectively reduced.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic diagram of cable offset versus measurement for a PCB split Rogowski coil in accordance with the present invention;

FIG. 2 is a schematic diagram of the distribution of the turn portions and the turn lacking portions of a split Rogowski coil of a PCB according to the present invention;

FIG. 3 is a schematic wiring diagram of a PCB split Rogowski coil in accordance with the present invention;

fig. 4 is a schematic diagram illustrating a test result of a rogowski coil of a PCB opening according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings.

Fig. 2 shows a PCB split rogowski coil in accordance with an embodiment of the present invention. As can be seen from fig. 2, the open-ended rogowski coil of the PCB of this embodiment includes a first semicircular PCB block 1 and a second semicircular PCB block 2, the first semicircular PCB block 1 and the second semicircular PCB block 2 are butted to form a complete PCB rogowski coil, both the front and the back of the first semicircular PCB block 1 and the second semicircular PCB block 2 are wired simultaneously, and are uniformly provided with a turn portion 3 and a turn-missing portion 4 during wiring, the turn portion 3 and the turn-missing portion 4 are arranged at intervals, the central angle corresponding to each turn portion 3 is kept consistent, and the central angle corresponding to each turn-missing portion 4 is also kept consistent. In this embodiment, eight winding turn portions 3 are uniformly distributed on the circumference of the open rogowski coil of the PCB, so that the central angle corresponding to each winding turn portion 3 is 33 °, and the central angle corresponding to each missing turn portion is 12 °. 12 windings are arranged in each turn portion 3, and the central angle interval between the windings of each set is 3 °.

Fig. 3 is a schematic diagram of the open rogowski coil wiring of the PCB according to the embodiment of the present invention. The open Rogowski coil of the PCB comprises two windings of a forward winding 10 and a reverse winding 11, each winding in each winding part 3 comprises a turn of the forward winding 10 and a turn of the reverse winding 11, namely, each winding part 3 in the embodiment comprises 12 turns of the forward winding and 12 turns of the reverse winding, each turn of the forward winding 10 comprises a forward winding inlet wire 101, the forward winding inlet wire 101 passes through a forward winding far end via hole 102 and then is routed to a forward winding near end via hole 103 on the back of the PCB, and the routing passes through the forward winding near end via hole 103 and then is routed to a forward winding outlet wire 104 on the front of the PCB. The outgoing line 104 of each forward winding 10 is connected to the incoming line 101 of the next forward winding 10. The incoming wire 101 of the first turn forward winding 10 of each turn section 3 is routed in the missing turn section 4 along the circumference of the open rogowski coil of the PCB.

Similarly, each turn of the reverse winding 11 includes a reverse winding incoming line 111, and the reverse winding incoming line 111 passes through the reverse winding near-end via hole 112 on the back side of the PCB, passes through the reverse winding near-end via hole 112, passes through the reverse winding far-end via hole 113 on the front side of the PCB, and is connected to the reverse winding outgoing line 114 through the reverse winding far-end via hole 113. The outgoing line 114 of each reverse winding 11 is connected to the incoming line 111 of the next reverse winding 11. The outgoing wire 114 of the last turn of the reverse winding 11 of each turn section 3 is routed along the circumference of the open rogowski coil of the PCB in the missing turn section 4.

Fig. 4 is a schematic diagram of a test result of the open rogowski coil of the PCB of this embodiment, and it can be seen from fig. 4 that when the cable is shifted by 15mm from the center of the coil, the measurement error of the rogowski coil of the PCB can still be kept within five ten thousandths.

The above description is only an embodiment of the present invention, and the protection scope of the present invention is not limited thereto, and any person skilled in the art should modify or replace the present invention within the technical specification of the present invention.

Claims

1. The annular opening PCB Rogowski coil with sectional wiring is characterized in that the opening PCB Rogowski coil comprises a first semicircular PCB block and a second semicircular PCB block, and the first semicircular PCB block and the second semicircular PCB block are spliced to form a complete annular PCB Rogowski coil;

2. The segmented routed annular open-ended PCB rogowski coil of claim 1, wherein the open-ended PCB rogowski coil comprises both forward and reverse windings, each forward winding comprising a forward winding inlet wire, the forward winding inlet wire routed through a forward winding distal end via hole on the back side of the PCB to a forward winding proximal end via hole, the wire routed through a forward winding proximal end via hole on the front side to a forward winding outlet wire;

the outgoing line of each turn of forward winding is connected with the incoming line of the next turn of forward winding, and the incoming line of the first turn of forward winding of each turn part is arranged along the circumference of the open PCB Rogowski coil in the turn-missing part.

3. The segmented routed annular open-ended PCB rogowski coil of claim 2, wherein each turn of reverse winding comprises a reverse winding inlet wire, the reverse winding inlet wire being routed through the reverse winding proximal via hole on the back side of the PCB, routed through the reverse winding proximal via hole, routed through the front side of the PCB to the reverse winding distal via hole, and connected to the reverse winding outlet wire through the reverse winding distal via hole;

4. The segmented routed annular open-ended PCB Rogowski coil of claim 3, wherein eight sets of turn portions are uniformly distributed around the circumference of the open-ended PCB Rogowski coil, each turn portion having a central angle of 33 ° and each turn-missing portion having a central angle of 12 °.

5. The segmented routed annular open PCB rogowski coil of claim 4, wherein 12 sets of windings are routed in each turn portion, the central angle spacing between each set of windings being 3 °.