CN110488068A - A kind of sampling unit on capacitance type potential transformer - Google Patents

Abstract

The invention discloses a sampling unit on a capacitive voltage transformer, which relates to the technical field of power equipment detection; it includes a terminal N', a terminal X', and a terminal da', connection terminal dn', clamp meter measurement point P, first switch K1, second switch K2 and discharge tube D1, the connection terminal N' is connected to the clamp meter measurement point P and first switch K1 in sequence The ground, the discharge tube D1 is connected in parallel with the first switch K1, and the connection terminal X' is connected to the ground through the second switch K2; it corresponds to the detection terminal N', Connection terminal X', connection terminal da', connection terminal dn', clamp meter measuring point P, first switch K1, second switch K2, discharge tube D1, etc. improve detection efficiency and safety.

Description

A sampling unit on a capacitive voltage transformer

technical field

The invention relates to the technical field of electric equipment detection, in particular to a sampling unit on a capacitive voltage transformer.

Background technique

At present, capacitive voltage transformer is a common primary equipment in substation.

As shown in Figure 3, the main structure of a capacitive voltage transformer includes a capacitive voltage divider and an electromagnetic unit. The capacitive voltage divider is composed of a high-voltage capacitor C1 and a medium-voltage capacitor C2 in series. The transformer steps down to provide voltage signals for voltage measurement and relay protection devices. The electromagnetic unit consists of intermediate transformer, compensating reactor, damper, oil tank and secondary terminal box. The secondary terminal box has the terminal X of the primary winding of the intermediate transformer, the low-voltage terminal N, the primary secondary winding 1a1n, the primary secondary winding 2a2n and the residual voltage winding dadn drawn from the capacitor voltage transformer.

At present, there are many inconveniences in the maintenance and testing of capacitive voltage transformers.

First, because the secondary terminal boxes of 220kV and 110kV capacitive voltage transformers in the substation are relatively high from the ground, it brings great inconvenience to various power outages and live tests. When conducting capacitance and dielectric loss factor tests, the staff need to climb up the structure through a ladder, open the secondary terminal box for test wiring, and need to use a screwdriver or pliers to repeatedly open and restore the wiring of the secondary terminal, which is time-consuming and labor-intensive. Operators are at risk of miswiring and falling from heights.

Second, capacitive voltage transformers are important capacitive equipment in substations, and play a vital role in metering and relay protection. Currently, there are a large number of 220kV and 110kV capacitive voltage transformers in substations, but they cannot be developed Compared with dielectric loss factor and capacitance ratio detection and overall capacitance test, the lack of effective live detection means makes the insulation supervision of capacitive voltage transformers potential hidden dangers.

Third, when the lightning arrester is live-tested to obtain phase information, because there is no suitable measurement point, the existing method is to obtain the voltage signal on the secondary circuit of the voltage transformer hui control cabinet voltage transformer. The process of obtaining the signal has the risk of causing a secondary short circuit.

Existing technical problems and thinking:

How to solve the existing technical problems of low detection efficiency and poor safety.

Contents of the invention

The technical problem to be solved by the present invention is to provide a sampling unit on a capacitive voltage transformer, which corresponds to the connecting terminal N', connecting terminal X', connecting terminal da' used for detection through the terminal of the same name of the capacitive voltage transformer , connection terminal dn', clamp meter measurement point P, first switch K1, second switch K2 and discharge tube D1, etc., to achieve improved detection efficiency and good safety.

In order to solve the above-mentioned technical problems, the technical solution adopted by the present invention is: the connection terminal N', the connection terminal X', the connection terminal da', the connection terminal dn', clamp Meter measuring point P, first switch K1, second switch K2 and discharge tube D1, the terminal N' is connected to the ground through clamp meter measuring point P and first switch K1 in turn, and the discharge tube D1 is connected to the second A switch K1 is connected in parallel, and the connection terminal X' is connected to the ground through the second switch K2.

The further technical solution is: it also includes the connection terminal N, connection terminal X, connection terminal da and connection terminal dn corresponding to the terminal with the same name of the capacitor voltage transformer, and the terminal with the same name of the capacitor voltage transformer is corresponding to the detection. The connecting terminal of the terminal is electrically connected with the connecting terminal corresponding to the end of the same name.

A further technical solution is that: the connection terminal corresponding to the terminal with the same name of the capacitive voltage transformer for detection is electrically connected to the connection terminal corresponding to the terminal with the same name for power introduction, so that the connection terminal N' is electrically connected to the connection terminal N, and the connection terminal N' is electrically connected to the connection terminal N. The connection terminal X' is electrically connected to the connection terminal X, the connection terminal da' is electrically connected to the connection terminal da, and the connection terminal dn' is electrically connected to the connection terminal dn.

A further technical solution is: it also includes a connection terminal GND connected to the ground.

A further technical solution is: the first switch K1 is a knife switch.

A further technical solution is: the second switch K2 is a knife switch.

A further technical solution is: it also includes a panel, the connecting terminal N', the connecting terminal X', the connecting terminal da', the connecting terminal dn', the measuring point P of the clamp meter, the first switch K1, the second switch K2 and the discharge Tube D1 is provided on the panel.

A further technical solution is: it also includes a transition box, and the panel is arranged on the transition box.

A further technical solution is that: the measuring point P of the clamp meter is composed of a connecting terminal P1, a conductive sheet and a connecting terminal P2 connected in sequence.

A further technical solution is that the connection terminal is a plug-in connection terminal.

The beneficial effects produced by adopting the above-mentioned technical scheme are:

It corresponds to the detection terminal N', terminal X', terminal da', terminal dn', measuring point P of clamp meter, first switch K1, second switch K2 and discharge tube D1, etc., have achieved improved detection efficiency and good safety.

For details, see the description in the specific implementation mode.

Description of drawings

Fig. 1 is a schematic circuit diagram of the present invention;

Fig. 2 is panel diagram of the present invention;

Figure 3 is a circuit schematic diagram of a capacitive voltage transformer.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the application with reference to the drawings in the embodiments of the application. Apparently, the described embodiments are only some of the embodiments of the application, not all of them. The following description of at least one exemplary embodiment is merely illustrative in nature and in no way serves as any limitation of the application, its application or uses. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of this application.

In the following description, a lot of specific details are set forth in order to fully understand the application, but the application can also be implemented in other ways different from those described here, and those skilled in the art can do without violating the connotation of the application. By analogy, the present application is therefore not limited by the specific embodiments disclosed below.

It should be noted that the terminology used here is only for describing specific implementations, and is not intended to limit the exemplary implementations according to the present application. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural, and it should also be understood that when the terms "comprising" and/or "comprising" are used in this specification, they mean There are features, steps, operations, means, components and/or combinations thereof.

The relative arrangements of components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present application unless specifically stated otherwise. At the same time, it should be understood that, for the convenience of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. Techniques, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods and devices should be considered part of the Authorized Specification. In all examples shown and discussed herein, any specific values should be construed as exemplary only, and not as limitations. Therefore, other examples of the exemplary embodiment may have different values. It should be noted that like numerals and letters denote like items in the following figures, therefore, once an item is defined in one figure, it does not require further discussion in subsequent figures.

In the description of the present application, it should be understood that orientation words such as "front, back, up, down, left, right", "horizontal, vertical, vertical, horizontal" and "top, bottom" etc. indicate the orientation Or positional relationship is generally based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the application and simplifying the description. In the absence of a contrary statement, these orientation words do not indicate or imply the device or element referred to It must have a specific orientation or be constructed and operated in a specific orientation, so it should not be construed as limiting the protection scope of the present application; the orientation words "inner and outer" refer to the inner and outer relative to the outline of each component itself.

For the convenience of description, spatially relative terms may be used here, such as "on ...", "over ...", "on the surface of ...", "above", etc., to describe the The spatial positional relationship between one device or feature shown and other devices or features. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, devices described as "above" or "above" other devices or configurations would then be oriented "beneath" or "above" the other devices or configurations. under other devices or configurations". Thus, the exemplary term "above" can encompass both an orientation of "above" and "beneath". The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptions used herein interpreted accordingly.

In addition, it should be noted that the use of words such as "first" and "second" to define components is only for the convenience of distinguishing corresponding components. To limit the protection scope of this application.

Example 1:

As shown in Fig. 1, the present invention discloses a sampling unit on a capacitive voltage transformer, which includes connecting terminal N', connecting terminal X', connecting terminal da' corresponding to the terminal with the same name of the capacitive voltage transformer , connecting terminal dn', clamp meter measuring point P, first switch K1, second switch K2 and discharge tube D1, the connecting terminal N' is connected to the earth through clamp meter measuring point P and first switch K1 in turn, The discharge tube D1 is connected in parallel with the first switch K1, and the connection terminal X' is connected to the ground through the second switch K2.

Example 2:

As shown in Fig. 1, the present invention discloses a sampling unit on a capacitive voltage transformer, which includes connecting terminal N', connecting terminal X', connecting terminal da' corresponding to the terminal with the same name of the capacitive voltage transformer Connecting terminal N, connecting terminal X, connecting terminal da and connecting terminal dn corresponding to terminal dn' and the terminal with the same name of capacitive voltage transformer, as well as measuring point P of clamp meter, first switch K1, second The switch K2 and the discharge tube D1, the terminal N' is connected to the ground through the measuring point P of the clamp meter and the first switch K1 in turn, the discharge tube D1 is connected in parallel with the first switch K1, and the terminal X' is connected to the ground through The second switch K2 is connected to the ground.

The terminal with the same name corresponding to the detection terminal of the capacitive voltage transformer is electrically connected to the terminal with the same name corresponding to the lead.

Example 3:

As shown in Fig. 1, the present invention discloses a sampling unit on a capacitive voltage transformer, which includes connecting terminal N', connecting terminal X', connecting terminal da' corresponding to the terminal with the same name of the capacitive voltage transformer Connecting terminal N, connecting terminal X, connecting terminal da and connecting terminal dn corresponding to terminal dn' and the terminal with the same name of capacitive voltage transformer, as well as measuring point P of clamp meter, first switch K1, second The switch K2 and the discharge tube D1, the terminal N' is connected to the ground through the measuring point P of the clamp meter and the first switch K1 in turn, the discharge tube D1 is connected in parallel with the first switch K1, and the terminal X' is connected to the ground through The second switch K2 is connected to the ground.

The terminal with the same name corresponding to the detection terminal of the capacitive voltage transformer is electrically connected to the terminal with the same name corresponding to the lead.

The connection terminal corresponding to the detection end of the capacitive voltage transformer is electrically connected to the connection terminal corresponding to the connection terminal of the same name end. The connection terminal N' is electrically connected to the connection terminal N, and the connection terminal X' is connected to the connection terminal The terminal X is electrically connected, the connecting terminal da' is electrically connected to the connecting terminal da, and the connecting terminal dn' is electrically connected to the connecting terminal dn.

Example 4:

As shown in Fig. 1, the present invention discloses a sampling unit on a capacitive voltage transformer, which includes connecting terminal N', connecting terminal X', connecting terminal da' corresponding to the terminal with the same name of the capacitive voltage transformer Connecting terminal N, connecting terminal X, connecting terminal da and connecting terminal dn corresponding to terminal dn' and the terminal with the same name of capacitive voltage transformer, as well as measuring point P of clamp meter, first switch K1, second The switch K2, the discharge tube D1 and the connection terminal GND connected to the earth, the connection terminal N' is connected to the earth through the measuring point P of the clamp meter, the first switch K1 and the connection terminal GND in turn, and the discharge tube D1 is connected to the first The parallel terminal of the switch K1 is connected to the ground through the second switch K2 and the terminal GND in sequence.

The terminal with the same name corresponding to the detection terminal of the capacitive voltage transformer is electrically connected to the terminal with the same name corresponding to the lead.

The connection terminal corresponding to the detection end of the capacitive voltage transformer is electrically connected to the connection terminal corresponding to the connection terminal of the same name end. The connection terminal N' is electrically connected to the connection terminal N, and the connection terminal X' is connected to the connection terminal The terminal X is electrically connected, the connecting terminal da' is electrically connected to the connecting terminal da, and the connecting terminal dn' is electrically connected to the connecting terminal dn.

Example 5:

As shown in Fig. 1, the present invention discloses a sampling unit on a capacitive voltage transformer, which includes connecting terminal N', connecting terminal X', connecting terminal da' corresponding to the terminal with the same name of the capacitive voltage transformer Connecting terminal N, connecting terminal X, connecting terminal da and connecting terminal dn corresponding to terminal dn' and the terminal with the same name of capacitive voltage transformer, as well as measuring point P of clamp meter, first switch K1, second The switch K2, the discharge tube D1 and the connection terminal GND connected to the earth, the connection terminal N' is connected to the earth through the measuring point P of the clamp meter, the first switch K1 and the connection terminal GND in turn, and the discharge tube D1 is connected to the first The parallel terminal of the switch K1 is connected to the ground through the second switch K2 and the terminal GND in sequence.

The terminal with the same name corresponding to the detection terminal of the capacitive voltage transformer is electrically connected to the terminal with the same name corresponding to the lead.

The connection terminal corresponding to the detection end of the capacitive voltage transformer is electrically connected to the connection terminal corresponding to the connection terminal of the same name end. The connection terminal N' is electrically connected to the connection terminal N, and the connection terminal X' is connected to the connection terminal The terminal X is electrically connected, the connecting terminal da' is electrically connected to the connecting terminal da, and the connecting terminal dn' is electrically connected to the connecting terminal dn.

The first switch K1 is a knife switch.

Embodiment 6:

As shown in Fig. 1, the present invention discloses a sampling unit on a capacitive voltage transformer, which includes connecting terminal N', connecting terminal X', connecting terminal da' corresponding to the terminal with the same name of the capacitive voltage transformer Connecting terminal N, connecting terminal X, connecting terminal da and connecting terminal dn corresponding to terminal dn' and the terminal with the same name of capacitive voltage transformer, as well as measuring point P of clamp meter, first switch K1, second The switch K2, the discharge tube D1 and the connection terminal GND connected to the earth, the connection terminal N' is connected to the earth through the measuring point P of the clamp meter, the first switch K1 and the connection terminal GND in turn, and the discharge tube D1 is connected to the first The parallel terminal of the switch K1 is connected to the ground through the second switch K2 and the terminal GND in sequence.

The terminal with the same name corresponding to the detection terminal of the capacitive voltage transformer is electrically connected to the terminal with the same name corresponding to the lead.

The connection terminal corresponding to the detection end of the capacitive voltage transformer is electrically connected to the connection terminal corresponding to the connection terminal of the same name end. The connection terminal N' is electrically connected to the connection terminal N, and the connection terminal X' is connected to the connection terminal The terminal X is electrically connected, the connecting terminal da' is electrically connected to the connecting terminal da, and the connecting terminal dn' is electrically connected to the connecting terminal dn.

The first switch K1 is a knife switch.

The second switch K2 is a knife switch.

Embodiment 7:

As shown in Fig. 1 and Fig. 2, the present invention discloses a sampling unit on a capacitive voltage transformer, including a panel, and a connection terminal N' corresponding to the detection end of the capacitive voltage transformer fixed on the panel , connection terminal X', connection terminal da' and connection terminal dn', terminal N, connection terminal X, connection terminal da and connection terminal dn corresponding to the end of the capacitive voltage transformer, and clamp meter measurement Point P, the first switch K1, the second switch K2, the discharge tube D1 and the connection terminal GND connected to the earth, the connection terminal N' is connected to the clamp meter measurement point P, the first switch K1 and the connection terminal GND in sequence The ground, the discharge tube D1 is connected in parallel with the first switch K1, and the connection terminal X' is connected to the ground through the second switch K2 and the connection terminal GND in turn.

The terminal with the same name corresponding to the detection terminal of the capacitive voltage transformer is electrically connected to the terminal with the same name corresponding to the lead.

The connection terminal corresponding to the detection end of the capacitive voltage transformer is electrically connected to the connection terminal corresponding to the connection terminal of the same name end. The connection terminal N' is electrically connected to the connection terminal N, and the connection terminal X' is connected to the connection terminal The terminal X is electrically connected, the connecting terminal da' is electrically connected to the connecting terminal da, and the connecting terminal dn' is electrically connected to the connecting terminal dn.

The first switch K1 is a knife switch.

The second switch K2 is a knife switch.

Embodiment 8:

As shown in Fig. 1 and Fig. 2, the present invention discloses a sampling unit on a capacitive voltage transformer, including a transfer box, a panel fixed on the transfer box, and a capacitive voltage transformer fixed on the panel Connecting terminal N', connecting terminal X', connecting terminal da' and connecting terminal dn' corresponding to the terminal with the same name for detection, connecting terminal N, connecting terminal X and connecting terminal corresponding to the terminal with the same name of the capacitive voltage transformer Terminal da and connecting terminal dn and clamp meter measuring point P, first switch K1, second switch K2, discharge tube D1 and connecting terminal GND connected to the earth, said connecting terminal N' passing through clamp meter measuring point P in turn 1. The first switch K1 and the connection terminal GND are connected to the ground, the discharge tube D1 is connected in parallel with the first switch K1, and the connection terminal X' is connected to the ground through the second switch K2 and the connection terminal GND in turn.

The terminal with the same name corresponding to the detection terminal of the capacitive voltage transformer is electrically connected to the terminal with the same name corresponding to the lead.

The connection terminal corresponding to the detection end of the capacitive voltage transformer is electrically connected to the connection terminal corresponding to the connection terminal of the same name end. The connection terminal N' is electrically connected to the connection terminal N, and the connection terminal X' is connected to the connection terminal The terminal X is electrically connected, the connecting terminal da' is electrically connected to the connecting terminal da, and the connecting terminal dn' is electrically connected to the connecting terminal dn.

The first switch K1 is a knife switch.

The second switch K2 is a knife switch.

Embodiment 9:

As shown in Fig. 1 and Fig. 2, the present invention discloses a sampling unit on a capacitive voltage transformer, including a transfer box, a panel fixed on the transfer box, and a capacitive voltage transformer fixed on the panel Connecting terminal N', connecting terminal X', connecting terminal da' and connecting terminal dn' corresponding to the terminal with the same name for detection, connecting terminal N, connecting terminal X and connecting terminal corresponding to the terminal with the same name of the capacitive voltage transformer Terminal da and connecting terminal dn and clamp meter measuring point P, first switch K1, second switch K2, discharge tube D1 and connecting terminal GND connected to the earth, said connecting terminal N' passing through clamp meter measuring point P in turn 1. The first switch K1 and the connection terminal GND are connected to the ground, the discharge tube D1 is connected in parallel with the first switch K1, and the connection terminal X' is connected to the ground through the second switch K2 and the connection terminal GND in turn.

The terminal with the same name corresponding to the detection terminal of the capacitive voltage transformer is electrically connected to the terminal with the same name corresponding to the lead.

The connection terminal corresponding to the detection end of the capacitive voltage transformer is electrically connected to the connection terminal corresponding to the connection terminal of the same name end. The connection terminal N' is electrically connected to the connection terminal N, and the connection terminal X' is connected to the connection terminal The terminal X is electrically connected, the connecting terminal da' is electrically connected to the connecting terminal da, and the connecting terminal dn' is electrically connected to the connecting terminal dn.

The first switch K1 is a knife switch.

The second switch K2 is a knife switch.

The measuring point P of the clamp meter is composed of a connecting terminal P1, a conductive sheet and a connecting terminal P2 connected in sequence.

Example 10:

As shown in Fig. 1 and Fig. 2, the present invention discloses a sampling unit on a capacitive voltage transformer, including a transfer box, a panel fixed on the transfer box, and a capacitive voltage transformer fixed on the panel Connecting terminal N', connecting terminal X', connecting terminal da' and connecting terminal dn' corresponding to the terminal with the same name for detection, connecting terminal N, connecting terminal X and connecting terminal corresponding to the terminal with the same name of the capacitive voltage transformer Terminal da and connecting terminal dn and clamp meter measuring point P, first switch K1, second switch K2, discharge tube D1 and connecting terminal GND connected to the earth, said connecting terminal N' passing through clamp meter measuring point P in turn 1. The first switch K1 and the connection terminal GND are connected to the ground, the discharge tube D1 is connected in parallel with the first switch K1, and the connection terminal X' is connected to the ground through the second switch K2 and the connection terminal GND in turn.

The terminal with the same name corresponding to the detection terminal of the capacitive voltage transformer is electrically connected to the terminal with the same name corresponding to the lead.

The connection terminal corresponding to the detection end of the capacitive voltage transformer is electrically connected to the connection terminal corresponding to the connection terminal of the same name end. The connection terminal N' is electrically connected to the connection terminal N, and the connection terminal X' is connected to the connection terminal The terminal X is electrically connected, the connecting terminal da' is electrically connected to the connecting terminal da, and the connecting terminal dn' is electrically connected to the connecting terminal dn.

The first switch K1 is a knife switch.

The second switch K2 is a knife switch.

The measuring point P of the clamp meter is composed of a connecting terminal P1, a conductive sheet and a connecting terminal P2 connected in sequence.

The terminal block is a plug-in type terminal block.

Compared with the above embodiments, the panel is made of insulating material, and is installed and fixed in the junction box.

Compared with the above embodiment, the N' loop includes the first knife switch K1, the discharge tube D1 and the measuring point P of the clamp meter.

Compared with the above-mentioned embodiment, the X' circuit includes the second knife switch K1.

Compared with the above-mentioned embodiments, the measuring point P of the clamp meter is a bare conductor protruding in the middle, and the protrusion in the middle ensures that the clamp ammeter can clamp the main conductor for current measurement.

Compared with the above-mentioned embodiments, the connecting wires should be protected by insulation.

Compared with the above-mentioned embodiments, the transition box is a metal shell, which has anti-corrosion and rain-proof functions.

The inventive concept of the application:

It corresponds to the detection terminal N', terminal X', terminal da', terminal dn', measuring point P of clamp meter, first switch K1, second switch K2 and discharge tube D1, etc., have achieved improved detection efficiency and good safety.

Through the capacitive voltage transformer sampling unit, the terminals commonly used in the secondary terminal box are led out to the sampling unit.

The sampling unit enables the above-mentioned various tests to be completed without the operator opening the secondary terminal box of the capacitive voltage transformer. The technical problems of low efficiency and poor safety of existing test methods are solved.

Instructions for use:

Early preparation:

The invention can be installed on the pillar of the capacitive voltage transformer through the metal hoop.

Connect terminal da of capacitive voltage transformer to terminal da with wires, connect terminal dn of capacitive voltage transformer to terminal dn with wires, connect terminal X of capacitive voltage transformer to wiring The terminal X is electrically connected with a wire, and the terminal N of the capacitive voltage transformer is electrically connected with the terminal N with a wire.

When the capacitive voltage transformer operates normally, the knife switch must be closed, and the discharge tube must be installed in place.

As shown in Figure 3, when the sampling unit is used to measure the capacitance and dielectric loss factor of the high-voltage capacitor C12 and the medium-voltage capacitor C2 of the 220kV capacitive voltage transformer by the self-excitation method, the excitation line is connected to the sampling unit The extracted residual voltage winding terminal is terminal da' and the extracted residual voltage winding terminal is terminal dn', the high-voltage wire is connected to the low-voltage terminal N', and the signal line is connected to To the middle flange J of the 220kV capacitive voltage transformer, the knife switch mentioned in the N' loop must be opened at the same time during the test, and the discharge tube mentioned in the N' loop must be removed. Then the test can start.

When the sampling unit is used for M-type wiring to measure the capacitance and dielectric loss factor of the high-voltage capacitor C11 of the 220kV capacitive voltage transformer, connect the low-voltage terminal N' and the primary winding of the intermediate transformer The terminal terminal X' is short-circuited and connected to the signal line, the high-voltage line is connected to the middle flange of the 220kV capacitive voltage transformer, pull the knife switch in the N' circuit, and remove the N' The discharge tube described in the circuit, pull the knife switch described in the X' circuit, remove the discharge tube described in the X' circuit, and then start the test.

When the sampling unit is used for the live test of the arrester to obtain the voltage phase, it is necessary to use a clamp ammeter to clamp the clamp meter measurement point P for measurement.

When the sampling unit is used for the relative dielectric loss and capacitance measurement of the capacitive voltage transformer, it is necessary to first connect the low-voltage terminal N', which is the lead-out terminal, to the sensor of the test instrument, and pull the N' apart during the test. Circuit knife switch. After the test is completed, first close the knife switch of the N' loop and then remove the sensor of the testing instrument.

When the sampling unit is used for live testing of the overall capacitance of the capacitive voltage transformer, the clamp ammeter must be clamped to the measuring point P of the clamp meter for measurement, and the operating voltage of the test line shall be recorded at the same time.

Instructions:

1. When the sampling unit is used for the live test of the arrester to obtain the voltage phase, it is only necessary to use the clamp ammeter to connect to the designated position, and do not operate other components such as the knife switch. At this time, the clamp ammeter takes the capacitive current under the state of C1C2 in series, and obtains the voltage phase through the internal phase shift of the arrester live test instrument, which can realize the resistive current test of the arrester under the same operating voltage.

2. When the sampling unit is used for CVT power failure test:

a. Test C12 and C2 by self-excitation method. The excitation wire is connected to terminal da and terminal dn, the high voltage wire is connected to terminal N, and the signal wire is connected to the middle flange of CVT. The right X circuit knife switch and the discharge tube are closed, and then start the test.

b. When testing C11 with M-type wiring, short-circuit terminal N and terminal X, then connect the signal line, connect the high-voltage line to the middle flange of the CVT, and open all the knife switches and discharge tubes of the N circuit and X circuit at the same time, and then start the test.

3. When the sampling unit is used for the CVT relative dielectric loss and capacitance test, the terminal N should be connected to the ground first and then connected to the special sensor of the instrument. During the test, it is only necessary to open the switch of the N circuit. Close in time. Do not operate the N-circuit discharge tube and the right-hand X-circuit component. This method is used for the dielectric loss angle comparison test of two CVTs operating at the same voltage, that is, the phase angle difference analysis is carried out inside the special tester after taking the capacitive current in the C1C2 series state at the same time.

4. When the sampling unit is used for the live test of the overall capacitance of the CVT, use the clamp ammeter with a range of 0-1A to connect to the designated position, read the data, and record the operating voltage of the line at the same time. The clamp ammeter takes the capacitance current, which can be calculated The total capacitance of C1C2 in series.

Beneficial Effect Description:

The present invention leads the commonly used terminals in the secondary terminal box of the 220kV line capacitive voltage transformer to the transfer box of the sampling unit, and realizes the following functions:

1. The power failure test of the capacitive voltage transformer does not require the operator to climb up and open the secondary terminal box to complete the test. The technical problems of low efficiency and poor safety of existing test methods are solved.

2. Since the end of the voltage dividing capacitor is drawn out, it creates conditions for the relative dielectric loss factor and capacitance ratio detection of the capacitor voltage transformer and the overall capacitance test. The live test fills the insulation of the capacitor voltage transformer in the operating state. Gaps in oversight.

3. Since the device provides a capacitive current test circuit and test points, the live test of the arrester does not need to take the voltage signal according to the traditional method, eliminating the risk of PT secondary short circuit.

The sampling unit enables the above-mentioned various tests to be completed without the operator opening the secondary terminal box of the capacitive voltage transformer. The technical problems of low efficiency and poor safety of existing test methods are solved.

Claims (10)

1. the sampling unit on a kind of capacitance type potential transformer, it is characterised in that: including the of the same name of capacitance type potential transformer Hold the connecting terminal N ' of corresponding detection, connecting terminal X ', connecting terminal da ', connecting terminal dn ', split-core type meter measurement point P, First switch K1, second switch K2 and discharge tube D1, the connecting terminal N ' is successively through split-core type meter measurement point P and first switch K1 It is connected to the earth, the discharge tube D1 and first switch K1 parallel connected end, the connecting terminal X ' is connected to greatly through second switch K2 Ground.

2. the sampling unit on a kind of capacitance type potential transformer according to claim 1, it is characterised in that: further include electricity Corresponding connecting terminal N, connecting terminal X, connecting terminal da and the connecting terminal for drawing electricity of the Same Name of Ends of appearance formula voltage transformer Dn, the connecting terminal of the corresponding detection of the Same Name of Ends of the capacitance type potential transformer terminals for drawing electricity corresponding with Same Name of Ends Son electrical connection.

3. the sampling unit on a kind of capacitance type potential transformer according to claim 2, it is characterised in that: capacitive battery The connecting terminal of the corresponding detection of Same Name of Ends of the mutual inductor connecting terminal for drawing electricity corresponding with Same Name of Ends is pressed to electrically connect as The connecting terminal N ' is electrically connected with connecting terminal N, and the connecting terminal X ' is electrically connected with connecting terminal X, the connecting terminal Da ' is electrically connected with connecting terminal da, and the connecting terminal dn ' is electrically connected with connecting terminal dn.

4. the sampling unit on a kind of capacitance type potential transformer according to claim 1, it is characterised in that: further include connecting It is connected to the connecting terminal GND of the earth.

5. the sampling unit on a kind of capacitance type potential transformer according to claim 1, it is characterised in that: described first Switch K1 is chopper switch.

6. the sampling unit on a kind of capacitance type potential transformer according to claim 1, it is characterised in that: described second Switch K2 is chopper switch.

7. the sampling unit on a kind of capacitance type potential transformer according to claim 1, it is characterised in that: further include face Plate, the connecting terminal N ', connecting terminal X ', connecting terminal da ', connecting terminal dn ', split-core type meter measurement point P, first switch K1, second switch K2 and discharge tube D1 are arranged on panel.

8. the sampling unit on a kind of capacitance type potential transformer according to claim 7, it is characterised in that: further include turning Box is connect, the panel is arranged on interconnecting device.

9. the sampling unit on a kind of capacitance type potential transformer according to claim 1, it is characterised in that: the clamp Table measurement point P is made of sequentially connected connecting terminal P1, conductive sheet and connecting terminal P2.

10. the sampling unit on a kind of capacitance type potential transformer described according to claim 1~any one of 9, special Sign is: connecting terminal is plug-in type connection terminal.