CN103245834B - Deformation of transformer winding low-voltage impedance on-the-spot test method - Google Patents

Abstract

The present invention relates to a kind of deformation of transformer winding low-voltage impedance on-the-spot test method, its technical characteristics is: comprise adopt low-voltage impedance tester respectively the low-voltage impedance method of Hi-pot test point test transformer high-voltage centering pressure, at Hi-pot test point test transformer high-voltage to the low-voltage impedance method of low pressure with press short-circuit impedance method to low pressure in middle pressure test point test transformer.The present invention is reasonable in design, it adopts traditional low-voltage impedance tester low-voltage impedance that difference testing high voltage centering is pressed under the state of not tearing transformer lead open, high pressure to the low-voltage impedance of low pressure, middle pressure to the low-voltage impedance of low pressure, winding deformation is tested and is more close to on-the-spot operation reality, be in particular the measurement that is high, medium voltage side low-voltage impedance of oily tubing and casing Cable Transformer and provide convenient, quick, reliable measuring method.

Description

On-the-spot test method for low voltage impedance of transformer winding deformation

technical field

The invention belongs to the technical field of transformers, in particular to a field testing method for low-voltage impedance of transformer winding deformation.

Background technique

At present, when carrying out the winding deformation low-voltage impedance test of the transformer, it is necessary to remove the three-side leads of the transformer before proceeding. Especially for the oil-oil bushing cable outlet transformer, the cable compartment must be returned to the oil and the compartment door must be opened. The wiring test can be carried out, which greatly increases the workload of the on-site test personnel.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the prior art, and provide a field testing method for low-voltage impedance of transformer winding deformation with reasonable design, high reliability and easy use.

The present invention solves its technical problem and realizes by taking the following technical solutions:

A method for on-site testing of low-voltage impedance of transformer winding deformation, comprising: using a low-voltage impedance tester to test the low-voltage impedance of transformer high-voltage to medium-voltage at high-voltage test points, and testing the low-voltage impedance of transformer high-voltage to low voltage at high-voltage test points And test the medium voltage to low voltage short-circuit impedance method of the transformer at the medium voltage test point.

Moreover, the method for testing the low voltage impedance of high voltage to medium voltage includes the following steps:

(1) Separately disconnect the three isolating switches between the high-voltage side busbar, medium-voltage side busbar, low-voltage side busbar and transformer winding, thereby disconnecting the transformer from other primary equipment;

(2) Open the ground connection piece of the ground switch on the high-voltage side of the transformer, and connect it to the three channels of the low-voltage impedance tester for injecting and collecting test signals;

(3) Open the ground connection piece of the grounding switch on the medium voltage side of the transformer, and short-circuit the three phases of the transformer through wires to realize the short circuit on the medium voltage side;

(4) Make the grounding switch on the low-voltage side of the transformer in the disconnected state to realize the open circuit of the low-voltage side;

(5) Keep the neutral point of the transformer ungrounded;

⑹ After connecting in the above way, realize the low voltage impedance test function of high voltage to medium voltage through the low voltage impedance tester.

Moreover, the method for testing the low voltage impedance of high voltage to low voltage includes the following steps:

(1) Separately disconnect the three isolating switches between the high-voltage side busbar, medium-voltage side busbar, low-voltage side busbar and transformer winding, thereby disconnecting the transformer from other primary equipment;

(2) Open the ground connection piece of the ground switch on the high-voltage side of the transformer, and connect it to the three channels of the low-voltage impedance tester for injecting and collecting test signals;

(3) Open the grounding connection piece of the grounding switch on the low-voltage side of the transformer, and short-circuit the three phases of the transformer through wires to realize the short-circuit on the low-voltage side;

(4) Keep the grounding switch on the medium voltage side of the transformer in the off state to realize the open circuit of the medium voltage side;

(5) Keep the neutral point of the transformer ungrounded;

⑹ After connecting in the above way, realize the low voltage impedance test function of high voltage to low voltage through the low voltage impedance tester.

Moreover, the method for testing the low voltage impedance of medium voltage to low voltage includes the following steps:

(1) Separately disconnect the three isolating switches between the high-voltage side busbar, medium-voltage side busbar, low-voltage side busbar and transformer winding, thereby disconnecting the transformer from other primary equipment;

(2) Open the ground connection piece of the ground switch on the medium-voltage side of the transformer, and connect it to the three channels of the low-voltage impedance tester for injecting and collecting test signals;

(3) Open the grounding connection piece of the grounding switch on the low-voltage side of the transformer, and short-circuit the three phases of the transformer through wires to realize the short-circuit on the low-voltage side;

(4) Keep the grounding switch on the medium voltage side of the transformer in the off state to realize the open circuit of the medium voltage side;

(5) Keep the neutral point of the transformer ungrounded;

⑹ After connecting in the above way, the low voltage impedance test function of medium voltage to low voltage can be realized through the low voltage impedance tester.

Advantage and positive effect of the present invention are:

The invention has a reasonable design, and uses a traditional low-voltage impedance tester to separately test the low voltage impedance of high voltage to medium voltage, the low voltage impedance of high voltage to low voltage, and the low voltage impedance of medium voltage to low voltage without dismantling the lead wires of the transformer. It makes the winding deformation test closer to the actual on-site operation, and especially provides a convenient, fast and reliable measurement method for the measurement of the low voltage impedance of the high and medium voltage side of the oil-oil bushing cable transformer.

Description of drawings

Fig. 1 is the wiring principle diagram of the present invention.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings.

A transformer winding deformation low-voltage impedance on-site testing method, using the wiring schematic diagram shown in Figure 1 to connect a traditional low-voltage impedance tester with the transformer winding, the equipment and connecting lines in the figure are all three-phase symmetrical equipment, For clarity, it is represented by a single-phase graph according to the characteristics of the power system. The test method of the present invention comprises the method of using a low voltage impedance tester to test the low voltage impedance of transformer high voltage to medium voltage at the high voltage test point, the method of testing the low voltage impedance of transformer high voltage to low voltage at the high voltage test point and the transformer at the medium voltage test point Short-circuit impedance method for medium voltage to low voltage. The specific method is:

The low voltage impedance method for testing high voltage to medium voltage consists of the following steps:

(1) Separately disconnect the three isolating switches (isolating switches 1, 2, 3) between the high-voltage side busbar, medium-voltage side busbar, low-voltage side busbar and the transformer winding, thereby disconnecting the transformer from other primary equipment without affecting Test Results;

(2) Open the ground connection piece of the ground switch (ground switch 1) on the high-voltage side of the transformer, and connect it to the three channels (A, B, and C phases) of the low-voltage impedance tester for injecting and collecting test signals;

(3) Open the ground connection piece of the grounding switch (grounding switch 2) on the medium voltage side of the transformer, and short-circuit the three phases of the transformer through wires to realize the short circuit on the medium voltage side;

(4) Make the grounding switch (grounding switch 3) on the low-voltage side of the transformer in the disconnected state to realize the open circuit of the low-voltage side;

(5) Keep the neutral point of the transformer ungrounded;

⑹ After connecting in the above way, the low voltage impedance test function of high voltage to medium voltage can be realized through the low voltage impedance tester.

The method of testing the low voltage impedance of high voltage to low voltage includes the following steps:

(1) Separately disconnect the three isolating switches (isolating switches 1, 2, 3) between the high-voltage side busbar, medium-voltage side busbar, low-voltage side busbar and the transformer winding, thereby disconnecting the transformer from other primary equipment without affecting Test Results;

(2) Open the ground connection piece of the ground switch (ground switch 1) on the high-voltage side of the transformer, and connect it to the three channels (A, B, and C phases) of the low-voltage impedance tester for injecting and collecting test signals;

(3) Open the grounding connection piece of the grounding switch (grounding switch 3) on the low-voltage side of the transformer, and short-circuit the three phases of the transformer through wires to realize the short-circuit on the low-voltage side;

(4) Make the grounding switch (grounding switch 2) on the medium voltage side of the transformer in the disconnected state to realize the open circuit of the medium voltage side;

(5) Keep the neutral point of the transformer ungrounded;

⑹ After connecting in the above way, the low voltage impedance test function of high voltage to low voltage can be realized through the low voltage impedance tester.

The low voltage impedance method for testing medium voltage to low voltage includes the following steps:

(1) Separately disconnect the three isolating switches (isolating switches 1, 2, 3) between the high-voltage side busbar, medium-voltage side busbar, low-voltage side busbar and the transformer winding, thereby disconnecting the transformer from other primary equipment without affecting Test Results;

(2) Open the ground connection piece of the ground switch (ground switch 2) on the medium voltage side of the transformer, and connect it to the three channels (A, B, C three-phase) of the low voltage impedance tester respectively for injecting and collecting test signals ;

(3) Open the grounding connection piece of the grounding switch (grounding switch 3) on the low-voltage side of the transformer, and short-circuit the three phases of the transformer through wires to realize the short-circuit on the low-voltage side;

(4) Make the grounding switch (grounding switch 2) on the medium voltage side of the transformer in the disconnected state to realize the open circuit of the medium voltage side;

(5) Keep the neutral point of the transformer ungrounded;

⑹ After connecting in the above way, the low voltage impedance test function of medium voltage to low voltage can be realized through the low voltage impedance tester.

It should be emphasized that the embodiments described in the present invention are illustrative rather than restrictive, so the present invention includes and is not limited to the embodiments described in the specific implementation, and those skilled in the art according to the technology of the present invention Other implementations derived from the scheme also belong to the protection scope of the present invention.

Claims (1)

1. A transformer winding deformation low-voltage impedance on-site testing method, comprising adopting a low-voltage impedance tester to test the low voltage impedance method of transformer high voltage to medium voltage at high voltage test points, and testing the low voltage of transformer high voltage to low voltage at high voltage test points An impedance method and a short-circuit impedance method for testing transformer medium voltage to low voltage at a medium voltage test point; characterized in that: The method for testing the low voltage impedance of high voltage to medium voltage comprises the following steps: (1) Separately disconnect the three isolating switches between the high-voltage side busbar, medium-voltage side busbar, low-voltage side busbar and transformer winding, thereby disconnecting the transformer from other primary equipment; (2) Open the ground connection piece of the ground switch on the high-voltage side of the transformer, and connect it to the three channels of the low-voltage impedance tester for injecting and collecting test signals; (3) Open the ground connection piece of the grounding switch on the medium voltage side of the transformer, and short-circuit the three phases of the transformer through wires to realize the short circuit on the medium voltage side; (4) Make the grounding switch on the low-voltage side of the transformer in the disconnected state to realize the open circuit of the low-voltage side; (5) Keep the neutral point of the transformer ungrounded; ⑹ After connecting in the above way, realize the low voltage impedance test function of high voltage to medium voltage through the low voltage impedance tester; The method for testing the low voltage impedance of high voltage to low voltage comprises the following steps: (1) Separately disconnect the three isolating switches between the high-voltage side busbar, medium-voltage side busbar, low-voltage side busbar and transformer winding, thereby disconnecting the transformer from other primary equipment; (2) Open the ground connection piece of the ground switch on the high-voltage side of the transformer, and connect it to the three channels of the low-voltage impedance tester for injecting and collecting test signals; (3) Open the grounding connection piece of the grounding switch on the low-voltage side of the transformer, and short-circuit the three phases of the transformer through wires to realize the short-circuit on the low-voltage side; (4) Keep the grounding switch on the medium voltage side of the transformer in the off state to realize the open circuit of the medium voltage side; (5) Keep the neutral point of the transformer ungrounded; ⑹ After connecting in the above way, realize the low voltage impedance test function of high voltage to low voltage through the low voltage impedance tester; The method for testing the low voltage impedance of medium voltage to low voltage comprises the following steps: (1) Separately disconnect the three isolating switches between the high-voltage side busbar, medium-voltage side busbar, low-voltage side busbar and transformer winding, thereby disconnecting the transformer from other primary equipment; (2) Open the ground connection piece of the ground switch on the medium-voltage side of the transformer, and connect it to the three channels of the low-voltage impedance tester for injecting and collecting test signals; (3) Open the grounding connection piece of the grounding switch on the low-voltage side of the transformer, and short-circuit the three phases of the transformer through wires to realize the short-circuit on the low-voltage side; (4) Keep the grounding switch on the medium voltage side of the transformer in the off state to realize the open circuit of the medium voltage side; (5) Keep the neutral point of the transformer ungrounded; ⑹ After connecting in the above way, the low voltage impedance test function of medium voltage to low voltage can be realized through the low voltage impedance tester.