Self-powered zero sequence current transformer

Abstract

The utility model discloses a self-powered zero sequence current transformer which comprises a current transformer body, an iron core is arranged in the current transformer body, a first copper wire is wound on the surface of the iron core, and the two ends of the first copper wire are a first starting end and a first tail end respectively. A second copper wire is wound on the surface of the iron core, and the winding direction of the second copper wire is opposite to that of the first copper wire. According to the self-powered zero-sequence current transformer, after the first tail end and the second tail end are connected, two independent windings are changed into one winding, the requirements for power supply voltage output signals and current protection input are met at the same time, the boundary dimension is reduced, installation operation is facilitated, and when the power supply winding is tested, the protection winding does not need to be in short circuit; when no one-time current inflow condition exists on a test site, test amplification can be changed according to self characteristics, the same effect is achieved, and operation is more convenient.

Description

TECHNICAL FIELD

[0001] The utility model relates to current transformer technical field, concretely is a kind of self-powered zero sequence current transformer. BACKGROUND

[0002] Current transformer is a kind of electrical equipment that large current is transformed into small current according to certain proportion, to provide small current signal proportional to primary side current for measuring instrument, relay protection device etc., to realize the monitoring, control and protection of power system.

[0003] In prior art, self-powered device zero sequence current transformer mostly has two independent secondary windings output, one group is used for power supply voltage output signal, another group is used for current protection input, resulting in that structure appearance is larger and installation is more inconvenient, and when testing power supply winding, protection winding needs to be short-circuited, and operation is more inconvenient. UTILITY MODEL CONTENT

[0004] In view of the deficiency of prior art, the utility model provides a kind of self-powered zero sequence current transformer, solve the problem that in prior art, self-powered device zero sequence current transformer mostly has two independent secondary windings output, when testing power supply winding, protection winding needs to be short-circuited, and operation is more inconvenient.

[0005] To realize above-mentioned purpose, the utility model is realized by the following technical scheme: a kind of self-powered zero sequence current transformer, including current transformer body, the inside of the current transformer body is provided with iron core, the surface of the iron core is wound and is provided with first copper wire, the two ends of the first copper wire are first head end and first end respectively, the surface of the iron core is wound and is provided with second copper wire, the winding direction of the second copper wire is opposite with the first copper wire.

[0006] The two ends of the second copper wire are first end and second end respectively, and the first end and the second end are connected to form a parallel connection end.

[0007] Further, the bottom of the current transformer body is detachably provided with two bottom plates, and the two ends of the lower surface of the bottom plate are provided with mounting holes.

[0008] Further, the two ends of the front side of the bottom plate are provided with bolts, the rear end of the bolt penetrates the bottom plate located at the rear side, and the nut is threadedly connected, and the top of the bolt is in contact with the bottom of the current transformer body.

[0009] Further, the surface of the bolt is movably provided with a non-slip pad, and the non-slip pad is located between the bottom plate at the rear side and the nut.

[0010] Further, the bottom plate is L-shaped.

[0011] Compared with the prior art, the utility model discloses the beneficial effect, through first end and second end connection, two independent windings become one, satisfy the voltage output signal and current protection input for power supply simultaneously, reduce the size, convenient operation, when testing the power supply winding, the protection winding does not need to be short-circuited, and when there is no primary current in the test site, can change the test mode according to the self characteristic, reach the same effect, and the operation is more convenient. BRIEF DESCRIPTION OF DRAWINGS

[0012] Fig. 1 It is the front structure schematic diagram of the utility model;

[0013] Fig. 2 It is the structure schematic diagram of the utility model bottom plate and bolt;

[0014] Fig. 3 It is the structure schematic diagram of the utility model current transformer body and bottom plate.

[0015] In the drawing: 1, iron core;2, first copper wire;3, first start end;4, first end;5, second copper wire;6, second start end;7, second end;8, parallel end;9, bottom plate;10, bolt;11, nut;12, non-slip gasket;13, mounting port;14, current transformer body. DETAILED DESCRIPTION

[0016] The technical scheme in the embodiments of the utility model will be described clearly and completely below in conjunction with the drawings in the embodiments of the utility model, and apparently, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by the person skilled in the art without creative labor are within the protection scope of the utility model.

[0017] Please refer to Figs. 1-3 The utility model provides a kind of technical scheme: a self-powered zero sequence current transformer, current transformer body 14 is arranged in the inside of current transformer body 14, and iron core 1 is arranged on the surface of iron core 1, and first copper wire 2 is wound on the surface of iron core 1, and the two ends of first copper wire 2 are first start end 3 and first end 4 respectively, second copper wire 5 is wound on the surface of iron core 1, and the winding direction of second copper wire 5 is opposite to that of first copper wire 2.

[0018] The two ends of second copper wire 5 are first end 4 and second end 7 respectively, and first end 4 and second end 7 are connected to form parallel end 8.

[0019] After the first end 4 is connected with the second end 7, two independent windings become one, and the power supply voltage output signal and the current protection input are simultaneously satisfied, the size is reduced, and the installation operation is facilitated.

[0020] When the power supply winding is tested, the protection winding does not need to be short-circuited, and at the same time, when there is no primary current input condition in the test site, the test mode can be changed according to the self characteristics, the same effect is achieved, and the operation is more convenient.

[0021] The first start end 3 and the parallel end 8 are power supply voltage output signal ends, and the second start end 6 and the parallel end 8 are current protection input test ends.

[0022] When the primary current P1 flows to P2 is 0.5A, the resistance between the first start end 3 and the parallel end 8 is 100 ohms, and the voltage is 46-53mV, and the primary current is 0.5A, 1A, 2A, 3A, 4A, 5A, and the corresponding power supply output signal voltage linear error meets the requirements.

[0023] When the test winding second start end 6 and the parallel end 8 pass through 0.3A current, the voltage between the first start end 3 and the parallel end 8 is not greater than 600mV, which meets the requirements.

[0024] When the primary current P1-P2 is 100A, there is no obvious abnormality between the first start end 3 and the parallel end 8, which indicates that the anti-saturation meets the requirements.

[0025] The bottom of the current transformer body 14 is detachably provided with two bottom plates 9, and the lower surfaces of the two bottom plates 9 are both provided with mounting holes 13.

[0026] Both ends of the front side of the front bottom plate 9 are provided with bolts 10, the rear ends of the bolts 10 penetrate the rear bottom plate 9, and the nuts 11 are threadedly connected, and the top of the bolt 10 is in contact with the bottom of the current transformer body 14.

[0027] After the bolt 10 and the nut 11 are threadedly connected, the two bottom plates 9 can be driven to approach each other, and after the bottom plate 9 is in contact with the surface of the iron core 1, the bolt 10 is in contact with the iron core 1, so that the iron core 1 can be clamped and fixed.

[0028] The transformer is divided into independent modules, the modules are connected by quick clamping, the modular design can improve the universality and flexibility of the product, and the transformer production and maintenance are facilitated.

[0029] The surface of the bolt 10 movably sheaths the anti-skid washer 12, the anti-skid washer 12 is located between the rear bottom plate 9 and the nut 11, and the anti-skid washer 12 improves the loosening performance of the nut 11.

[0030] In operation, the first end 4 is connected to the second end 7 to make two independent windings into one, while meeting the requirements for power supply voltage output signal and current protection input, reducing the size of the device and facilitating installation and operation.

[0031] It should be noted that the relational terms herein such as first and second and the like are used solely to distinguish one from another entity or action without necessarily requiring or implying any actual relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0032] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A self-powered zero-sequence current transformer, comprising a current transformer body (14), wherein an iron core (1) is disposed inside the current transformer body (14), characterized in that: The surface of the iron core (1) is wound with a first copper wire (2), the two ends of the first copper wire (2) are a first starting end (3) and a first ending end (4) respectively, and the surface of the iron core (1) is wound with a second copper wire (5), the winding direction of the second copper wire (5) is opposite to that of the first copper wire (2); The two ends of the second copper wire (5) are a first end (4) and a second end (7), respectively, and the first end (4) and the second end (7) are connected together to form a parallel end (8).

2. A self-powered zero-sequence current transformer according to claim 1, characterized in that: The bottom of the current transformer body (14) is provided with two base plates (9), and each of the two ends of the lower surface of the base plate (9) is provided with an installation port (13).

3. A self-powered zero-sequence current transformer according to claim 2, characterized in that: Bolts (10) are provided at both ends of the front side of the base plate (9) located on the front side. The rear end of the bolt (10) passes through the base plate (9) located on the rear side and is threaded with a nut (11). The top of the bolt (10) contacts the bottom of the current transformer body (14).

4. A self-powered zero-sequence current transformer according to claim 3, characterized in that: The surface of the bolt (10) is movably fitted with an anti-slip pad (12), which is located between the bottom plate (9) and the nut (11) on the rear side.

5. A self-powered zero-sequence current transformer according to claim 2, characterized in that: The base plate (9) is L-shaped.

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