System for testing secondary voltage drop of voltage transformer

Abstract

The utility model discloses a system for testing secondary voltage drop of a voltage transformer, which belongs to the field of electric power systems and is characterized in that on one hand, first voltage phasors of secondary terminals of single voltage transformers are acquired in a one-to-one correspondence manner through first voltage phasor acquisition devices; on the other hand, a second voltage phasor of each electric energy meter voltage terminal on the electric energy meter can be acquired through a single second voltage phasor acquisition device, and finally the second voltage phasor of each electric energy meter voltage terminal on the electric energy meter can be acquired through the processing device according to the first voltage phasor and the second voltage phasor in the secondary loop of each voltage transformer. The voltage transformer secondary voltage drop test system provided by the utility model has the advantages of simple structure and simplified devices, and can efficiently test the secondary voltage drops of a large number of voltage transformers in a transformer substation with low cost.

Description

Technical Field

[0001] The utility model relates to the field of power systems, in particular to a testing system for secondary voltage drop of a voltage transformer. Background Art

[0002] The comprehensive error in electric energy metering in power systems is composed of the comprehensive error in measurement caused by voltage transformer error, current transformer error, energy meter error, and the secondary voltage drop of the voltage transformer. Therefore, the secondary voltage drop of the voltage transformer used for metering in operation (the voltage drop of the secondary circuit line between the secondary side of the voltage transformer and the energy meter terminal) needs to be tested periodically. Understanding the energy metering error caused by this is of great significance for reducing the comprehensive error in energy metering and reducing billing losses. Regular measurement of the secondary voltage drop is conducive to improving the accuracy of electricity bill settlement. However, there is currently a lack of a mature test system for the secondary voltage drop of voltage transformers, making it difficult to test the secondary voltage drop of voltage transformers efficiently, and the testing cost is relatively high.

[0003] Therefore, how to provide a solution to the above technical problems is a problem that those skilled in the art need to solve at present. Utility Model Content

[0004] The purpose of the present utility model is to provide a test system for the secondary voltage drop of a voltage transformer. On the one hand, a first voltage phasor acquisition device is used to acquire the first voltage phasor of the secondary terminal of a single voltage transformer one by one. On the other hand, a single second voltage phasor acquisition device can be used to acquire the second voltage phasor of each voltage terminal on the electric energy meter. Finally, a processing device is used to determine the secondary voltage drop of each voltage transformer based on the first voltage phasor and the second voltage phasor in the secondary circuit of each voltage transformer. The test system has a simple structure and streamlined devices, and can test the secondary voltage drops of a large number of voltage transformers in a substation efficiently and at low cost.

[0005] In order to solve the above technical problems, the utility model provides a voltage transformer secondary voltage drop test system, which is applied to substations and includes:

[0006] A first voltage phasor acquisition device is connected to the secondary terminal of a single voltage transformer in a one-to-one correspondence, and is used to acquire a first voltage phasor of the secondary terminal of the connected voltage transformer;

[0007] a second voltage phasor acquisition device, connected to the voltage terminals of the electric energy meters in the secondary circuits of the voltage transformers, respectively, for acquiring the second voltage phasor of each of the connected electric energy meter voltage terminals;

[0008] The processing device is used to determine the secondary voltage drop of each voltage transformer based on the first voltage phasor and the second voltage phasor in the secondary circuit of each voltage transformer.

[0009] In another aspect, the processing device comprises:

[0010] a communication module, connected to the first voltage phasor acquisition device, the second voltage phasor acquisition device, and the controller, respectively, for respectively implementing a communication link between the first voltage phasor acquisition device, the second voltage phasor acquisition device, and the controller;

[0011] The controller is configured to determine the secondary voltage drop of the voltage transformer based on the first voltage phasor and the second voltage phasor in the secondary circuit of a single voltage transformer.

[0012] On the other hand, the first voltage phasor acquisition device and the second voltage phasor acquisition device are both voltage drop testers.

[0013] On the other hand, the controller is an original controller in the second voltage phasor acquisition device.

[0014] On the other hand, the communication module includes:

[0015] a mobile communication network, connected to the first voltage phasor acquisition device and the controller respectively;

[0016] A communication bus is connected to the second voltage phasor acquisition device and the controller respectively.

[0017] In another aspect, the mobile communication network comprises a fifth generation mobile communication network.

[0018] On the other hand, the voltage transformer secondary voltage drop test system also includes:

[0019] A prompting device is connected to the processing device and is used to prompt the identification of the voltage transformer whose secondary voltage drop error exceeds the standard under the control of the processing device.

[0020] On the other hand, the prompt device includes a local prompt module and a remote prompt module.

[0021] On the other hand, the voltage transformer secondary voltage drop test system also includes:

[0022] a memory connected to the processing device, for storing a secondary pressure drop error statistical table under the control of the processing device;

[0023] The secondary voltage drop error statistical table includes a conclusion on whether the secondary voltage drop error of each voltage transformer exceeds the standard.

[0024] The present invention provides a testing system for the secondary voltage drop of a voltage transformer. Taking into account that there is a certain distance between the various voltage transformers in the substation, and the secondary circuits of various voltage transformers are ultimately aggregated to the electric energy meter through the corresponding electric energy meter voltage terminals, the present invention, on the one hand, uses a first voltage phasor acquisition device to collect the first voltage phasor of the secondary terminal of a single voltage transformer one by one, and on the other hand, uses a single second voltage phasor acquisition device to collect the second voltage phasor of each electric energy meter voltage terminal on the electric energy meter. Finally, a processing device is used to determine the secondary voltage drop of each voltage transformer based on the first voltage phasor and the second voltage phasor in the secondary circuit of each voltage transformer. The testing system for the secondary voltage drop of the voltage transformer in the present invention has a simple structure and streamlined devices, and can efficiently and low-costly test the secondary voltage drops of a large number of voltage transformers in the substation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the relevant technologies and the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 This is a structural diagram of a voltage transformer secondary voltage drop testing system provided by the utility model;

[0027] Figure 2 This is a structural schematic diagram of another voltage transformer secondary voltage drop testing system provided by the utility model. DETAILED DESCRIPTION

[0028] The core of the present utility model is to provide a test system for the secondary voltage drop of a voltage transformer. On the one hand, the first voltage phasor of the secondary terminal of a single voltage transformer is collected one by one through a first voltage phasor acquisition device. On the other hand, the second voltage phasor of each voltage terminal of the electric energy meter can be collected through a single second voltage phasor acquisition device. Finally, the secondary voltage drop of each voltage transformer can be determined according to the first voltage phasor and the second voltage phasor in the secondary circuit of each voltage transformer through a processing device. The test system has a simple structure and streamlined devices, and can test the secondary voltage drops of a large number of voltage transformers in a substation efficiently and at low cost.

[0029] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a voltage transformer secondary voltage drop test system provided by the utility model. The voltage transformer secondary voltage drop test system is applied to a substation and includes:

[0031] A first voltage phasor acquisition device 1 is connected to the secondary terminal of a single voltage transformer in a one-to-one correspondence, and is used to acquire a first voltage phasor of the secondary terminal of the connected voltage transformer;

[0032] The second voltage phasor acquisition device 2 is connected to the voltage terminals of the electric energy meters in the secondary circuit of each voltage transformer, and is used to acquire the second voltage phasor of each connected electric energy meter voltage terminal;

[0033] The processing device 3 is used to determine the secondary voltage drop of each voltage transformer according to the first voltage phasor and the second voltage phasor in the secondary circuit of each voltage transformer.

[0034] Specifically, taking into account the technical problems in the above background technology, and considering that there is a certain distance between each voltage transformer in the substation, in the embodiment of the present invention, a first voltage phasor acquisition device 1 is connected to the secondary terminal of a single voltage transformer in a one-to-one correspondence, so as to acquire the first voltage phasor of the secondary terminal of the connected voltage transformer; and the secondary circuits of each voltage transformer are finally aggregated to the electric energy meter through the corresponding electric energy meter voltage terminal. Therefore, in the embodiment of the present invention, a second voltage phasor acquisition device 2 is used to connect the electric energy meter voltage terminal in the secondary circuit of each voltage transformer, so as to acquire the first voltage phasor of the connected electric energy meter; and the secondary circuits of each voltage transformer are finally aggregated to the electric energy meter through the corresponding electric energy meter voltage terminal. The second voltage phasor of each electric energy meter voltage terminal connected to the power transformer is connected, that is, the second voltage phasor of multiple electric energy meter voltage terminals can be collected by a single second voltage phasor acquisition device 2. In this way, multiple groups of first voltage phasors and second voltage phasors can be obtained. The secondary circuit of each voltage transformer corresponds to a group of first voltage phasors and second voltage phasors. The first voltage phasor is the voltage phasor on the secondary terminal side of the voltage transformer in the secondary circuit of the voltage transformer, and the second voltage phasor is the voltage phasor on the electric energy meter voltage terminal side in the secondary circuit. In theory, the smaller the difference between the first voltage phasor and the corresponding second voltage phasor, the better.

[0035] Among them, it is worth mentioning that since the substation supplies three-phase electricity to the power grid, the voltage phasor includes voltage amplitude and phase.

[0036] Specifically, in Figure 1 The secondary circuit of the voltage transformer can be understood more intuitively.

[0037] Among them, the processing device 3 can summarize all the first voltage phasors and the second voltage phasors, and determine the secondary voltage drop of the voltage transformer based on a group of first voltage phasors and second voltage phasors corresponding to the secondary circuit of a single voltage transformer. That is, the test system can efficiently determine the secondary voltage drop of a large number of voltage transformers in the substation, and has a simple structure, fewer components, and low cost.

[0038] In addition, it is worth mentioning that the processing device 3 can distinguish the first voltage phasors sent by each first voltage phasor acquisition device 1 in a variety of ways, and can also distinguish the second voltage phasors sent by the second voltage phasor acquisition device 2 in a variety of ways. For example, an identifier can be designed for each first voltage phasor acquisition device 1, and the interface used by the second voltage phasor acquisition device 2 to collect the second voltage phasor can be identified and distinguished, etc. The embodiment of the present utility model does not limit this.

[0039] The present invention provides a testing system for the secondary voltage drop of a voltage transformer. Taking into account that there is a certain distance between the various voltage transformers in the substation, and the secondary circuits of various voltage transformers are ultimately aggregated to the electric energy meter through the corresponding electric energy meter voltage terminals, the present invention, on the one hand, uses a first voltage phasor acquisition device to collect the first voltage phasor of the secondary terminal of a single voltage transformer one by one, and on the other hand, uses a single second voltage phasor acquisition device to collect the second voltage phasor of each electric energy meter voltage terminal on the electric energy meter. Finally, a processing device is used to determine the secondary voltage drop of each voltage transformer based on the first voltage phasor and the second voltage phasor in the secondary circuit of each voltage transformer. The testing system for the secondary voltage drop of the voltage transformer in the present invention has a simple structure and streamlined devices, and can efficiently and low-costly test the secondary voltage drops of a large number of voltage transformers in the substation.

[0040] Based on the above embodiment:

[0041] As an optional embodiment, the processing device 3 includes:

[0042] A communication module is connected to the first voltage phasor acquisition device 1, the second voltage phasor acquisition device 2 and the controller respectively, and is used to realize a communication link between the first voltage phasor acquisition device 1, the second voltage phasor acquisition device 2 and the controller respectively;

[0043] The controller is used to determine the secondary voltage drop of the voltage transformer according to the first voltage phasor and the second voltage phasor in the secondary circuit of the single voltage transformer.

[0044] Specifically, in order to collect data efficiently and stably, the processing device 3 in the embodiment of the present invention includes a communication module, which can be connected to the first voltage phasor acquisition device 1, the second voltage phasor acquisition device 2 and the controller respectively, and is used to realize the communication links between the first voltage phasor acquisition device 1 and the second voltage phasor acquisition device 2 and the controller respectively. Secondly, the core of data calculation can be the controller, which has the advantages of small size and low cost.

[0045] Of course, in addition to this specific structure, the processing device 3 can also be of other types, for example, in the form of a hardware circuit, which is not limited in the embodiment of the present invention.

[0046] As an optional embodiment, the first voltage phasor acquisition device 1 and the second voltage phasor acquisition device 2 are both voltage drop testers.

[0047] Specifically, the voltage drop tester has the advantages of small size, high maturity and strong reliability.

[0048] Of course, in addition to the voltage drop tester, the first voltage phasor acquisition device 1 and the second voltage phasor acquisition device 2 can also be of other types, which is not limited in the embodiment of the present invention.

[0049] As an optional embodiment, the controller is the original controller in the second voltage phasor acquisition device 2 .

[0050] Specifically, considering that the second voltage phasor acquisition device 2 already has a controller, the controller in the embodiment of the present invention may be the original controller in the second voltage phasor acquisition device 2, which can save costs.

[0051] Of course, in addition to the original controller in the second voltage phasor acquisition device 2, the controller can also be of various types, such as a management server, etc., and the embodiment of the present invention does not limit this.

[0052] As an optional embodiment, the communication module includes:

[0053] A mobile communication network is connected to the first voltage phasor acquisition device 1 and the controller respectively;

[0054] The communication bus is connected to the second voltage phasor acquisition device 2 and the controller respectively.

[0055] Specifically, considering that wireless communication has the advantage of simple wiring, and the electric energy meter is usually installed indoors, the signal of some wireless communication methods is poor indoors, and considering that the mobile communication network usually also has a strong signal indoors, the communication module in the embodiment of the present invention includes a mobile communication network, which is respectively connected to the first voltage phasor acquisition device 1 and the controller, and the controller in the voltage drop tester (second voltage phasor acquisition device 2) itself has bus communication with the second voltage phasor acquisition device 2. Therefore, the communication module in the embodiment of the present invention also includes a communication bus, which is respectively connected to the second voltage phasor acquisition device 2 and the controller.

[0056] The sampling rate of the controller for the first voltage phasor and the second voltage phasor should be at a certain level to ensure timely sampling.

[0057] As an optional embodiment, the mobile communication network includes a fifth generation mobile communication network.

[0058] Specifically, the fifth-generation mobile communication network (5G Network) has the advantages of high communication speed and strong stability.

[0059] Of course, in addition to the fifth-generation mobile communication network, the mobile communication network may also be of other types, which is not limited in the embodiments of the present invention.

[0060] As an optional embodiment, the voltage transformer secondary voltage drop testing system further includes:

[0061] The prompting device is connected to the processing device 3 and is used to prompt the identification of the voltage transformer whose secondary voltage drop error exceeds the standard under the control of the processing device 3.

[0062] Specifically, there are industry standards for the error of the secondary voltage drop of voltage transformers. The "Technical Management Regulations for Electric Energy Metering Devices" (DL / T 448-2016), an electric power industry standard of the People's Republic of China, stipulates the following for testing the secondary circuit and secondary voltage drop of voltage transformers used for metering: ① The secondary voltage drop of the secondary circuit of the voltage transformer in the power quality metering device should not be greater than 0.2% of its actual secondary voltage. Therefore, in order to enable staff to promptly detect the situation where the secondary voltage drop error exceeds the standard, the embodiment of the utility model may also include a prompt device connected to the processing device 3, which is used to indicate the identification of voltage transformers with excessive secondary voltage drop errors under the control of the processing device 3; that is, the processing device 3 can determine whether the secondary voltage drop error is higher than a preset threshold (for example, 0.2%). If it is higher, it is determined that the secondary voltage drop error exceeds the standard and the prompt device is controlled to issue a prompt.

[0063] Specifically, it is worth mentioning that the ratio difference and the angle difference of the voltage transformer secondary circuit can be calculated based on the first voltage phasor and the second voltage phasor, and then the error value of the secondary voltage drop can be calculated. The calculation formula of the error value of the secondary voltage drop can be:

[0064]

[0065] in, ΔU is the error value of the secondary voltage drop, U is the secondary output line or phase voltage (100V or 100 / √3V), f is the ratio difference (unit is percentage), and δ is the angle difference (unit is minute).

[0066] As an optional embodiment, the prompting device includes a local prompting module and a remote prompting module.

[0067] Specifically, in order to facilitate local and remote users to understand the prompt content in a timely manner, the prompt device in the embodiment of the present invention includes a local prompt module and a remote prompt module, both of which can be of various types. For example, the local prompt module can be a display, and the remote prompt module can be a mobile phone, etc. The embodiment of the present invention does not limit this.

[0068] As an optional embodiment, the voltage transformer secondary voltage drop testing system further includes:

[0069] A memory connected to the processing device 3, used for storing a secondary pressure drop error statistical table under the control of the processing device 3;

[0070] The secondary voltage drop error statistics table includes a conclusion on whether the secondary voltage drop error of each voltage transformer exceeds the standard.

[0071] Specifically, considering that the conclusions on whether the error of the secondary voltage drop of the voltage transformer collected each time exceeds the standard are of practical value, the memory in the embodiment of the utility model can store a secondary voltage drop error statistical table under the control of the processing device 3, including the conclusions on whether the error of the secondary voltage drop of each voltage transformer exceeds the standard.

[0072] The memory may be of various types, such as flash memory, etc., which is not limited in the embodiment of the present invention.

[0073] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the embodiments can be referred to each other. It should also be noted that in this specification, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of further restrictions, the elements defined by the sentence "comprise a..." do not exclude the presence of other identical elements in the process, method, article or equipment including the element.

[0074] The above description of the disclosed embodiments will enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A voltage transformer secondary voltage drop test system, characterized in that: Applied to substations, including: A first voltage phasor acquisition device is connected to the secondary terminal of a single voltage transformer in a one-to-one correspondence, and is used to acquire a first voltage phasor of the secondary terminal of the connected voltage transformer; A second voltage phasor acquisition device is connected to the voltage terminals of the electric energy meters in the secondary circuits of the voltage transformers respectively, and is used to acquire the second voltage phasors of the connected voltage terminals of the electric energy meters; A processing device is used to determine the secondary voltage drop of each voltage transformer according to the first voltage phasor and the second voltage phasor in the secondary circuit of each voltage transformer.

2. The voltage transformer secondary voltage drop test system according to claim 1, characterized in that: The processing device comprises: a communication module, connected to the first voltage phasor acquisition device, the second voltage phasor acquisition device and the controller, respectively, for respectively realizing a communication link between the first voltage phasor acquisition device, the second voltage phasor acquisition device and the controller; The controller is used to determine the secondary voltage drop of the voltage transformer according to the first voltage phasor and the second voltage phasor in the secondary circuit of the single voltage transformer.

3. The voltage transformer secondary voltage drop test system according to claim 2, characterized in that: The first voltage phasor acquisition device and the second voltage phasor acquisition device are both voltage drop testers.

4. The voltage transformer secondary voltage drop test system according to claim 3, characterized in that: The controller is an original controller in the second voltage phasor acquisition device.

5. The voltage transformer secondary voltage drop test system according to claim 4, characterized in that: The communication module comprises: A mobile communication network, connected to the first voltage phasor acquisition device and the controller respectively; A communication bus is connected to the second voltage phasor acquisition device and the controller respectively.

6. The voltage transformer secondary voltage drop test system according to claim 5, characterized in that: The mobile communication network comprises a fifth generation mobile communication network.

7. The voltage transformer secondary voltage drop test system according to claim 1, characterized in that: The voltage transformer secondary voltage drop test system also includes: A prompting device is connected to the processing device and is used to prompt the identification of the voltage transformer whose secondary voltage drop error exceeds the standard under the control of the processing device.

8. The voltage transformer secondary voltage drop test system according to claim 7, characterized in that: The prompt device includes a local prompt module and a remote prompt module.

9. The voltage transformer secondary voltage drop test system according to any one of claims 1 to 8, characterized in that: The voltage transformer secondary voltage drop test system also includes: A memory connected to the processing device, used for storing a secondary pressure drop error statistical table under the control of the processing device; The secondary voltage drop error statistical table includes a conclusion on whether the secondary voltage drop error of each voltage transformer exceeds the standard.

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