A method and system for detecting and analyzing saturation characteristics of an electromagnetic voltage transformer

Abstract

The application discloses a kind of electromagnetic voltage transformer saturation characteristic detection analysis method and detection system, detection analysis method includes: in the case where no direct-current voltage excitation is applied, from primary side, AC voltage excitation is applied;Saturation point under AC voltage is obtained;Step 2, in the case where given value of direct-current voltage excitation is applied to primary side, AC voltage excitation is simultaneously applied to primary side of electromagnetic voltage transformer, wherein the direct-current voltage applied is UDC;Step 3, saturation point under AC voltage and saturation point under direct-current component UDC are compared and analyzed, the influence of the direct-current component on the saturation characteristic of electromagnetic voltage transformer can be obtained.The application can analyze the influence of different direct-current components on the saturation characteristic of electromagnetic voltage transformer, which is used to guide the selection, operation and maintenance strategy of electromagnetic voltage transformer, thereby preventing the occurrence of electromagnetic voltage transformer failure, improving equipment safety, and further improving the safe and reliable operation level of power grid.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic voltage transformer testing technology, and in particular to a method and system for detecting and analyzing the saturation characteristics of electromagnetic voltage transformers. Background Technology

[0002] Electromagnetic voltage transformers are voltage transformers made using the principle of electromagnetic induction between windings. Their construction principle, wiring diagram, and operating characteristics are the same as those of power transformers. The load on the secondary side of an electromagnetic voltage transformer is the voltage coil of an instrument or relay. These coils have high impedance, carry very little current, and operate close to no-load conditions. Their design and use must prioritize achieving a certain level of accuracy. As an iron-core inductive element, the quality of the saturation characteristics of an electromagnetic voltage transformer is crucial for ensuring accuracy. With the construction of DC power grid projects and the integration of various energy sources, DC components are introduced into the system. These DC components affect the saturation characteristics of electromagnetic voltage transformers. Under overvoltage conditions, saturation is prone to occur, causing a surge in excitation current, triggering resonance, and in severe cases, causing fuse blowouts or voltage transformer equipment failure, affecting the safe operation of the power grid. Therefore, analyzing the impact of DC components on the saturation characteristics of electromagnetic voltage transformers is essential. Summary of the Invention

[0003] To meet user needs, the purpose of this application is to provide a method and system for detecting and analyzing the saturation characteristics of an electromagnetic voltage transformer, which takes into account the DC component.

[0004] To achieve the objectives of this invention, the technical solution is as follows:

[0005] First aspect

[0006] The present invention provides a method for detecting and analyzing the saturation characteristics of an electromagnetic voltage transformer, comprising the following steps:

[0007] Step 1: Without applying DC voltage excitation to the primary side of the electromagnetic voltage transformer, apply AC voltage excitation to the primary side, measure the voltage and current on the secondary side, calculate the saturation point, and obtain the saturation point U under AC voltage. bh0 ;

[0008] Step 2: While applying a given DC voltage excitation value to the primary side of the electromagnetic voltage transformer, simultaneously apply an AC voltage excitation value to the primary side, wherein the applied DC voltage is U. DC The applied AC voltage is measured at points according to a preset selection principle, up to the rated voltage of the equipment at the rated voltage factor. Voltage and current are measured on the secondary side to calculate the saturation point, yielding the DC component U. DCThe saturation point U below bh1 ;

[0009] Step 3: Combine the saturation point under AC voltage with the DC component U DC By comparing and analyzing the saturation point under different conditions, the influence of this DC component on the saturation characteristics of the electromagnetic voltage transformer can be determined, that is, the influence of this DC component U... DC The saturation point offset rate q is calculated as follows:

[0010] q=(U bh0 -U bh1 ) / U nh0 ×100%.

[0011] The preset point selection principle is as follows: the rated voltage of the electromagnetic voltage transformer is Un, and the rated voltage factor is denoted as F. Let U dn =Un-U DC The applied AC voltage is denoted as U. AC ,but

[0012]

[0013] Second aspect

[0014] The present invention provides an electromagnetic voltage transformer saturation characteristic detection system, comprising a DC voltage output unit, an AC voltage output unit, and a voltage and current measurement unit;

[0015] The DC voltage output unit is used to apply DC voltage excitation to the electromagnetic voltage transformer;

[0016] The AC voltage output unit is used to apply AC voltage excitation to the electromagnetic voltage transformer;

[0017] The voltage and current measurement unit is used to measure the secondary voltage and current of the electromagnetic voltage transformer.

[0018] The DC voltage output unit, AC voltage output unit, and voltage and current measurement unit perform saturation characteristic detection of the electromagnetic voltage transformer according to the following steps:

[0019] Step 1: Without applying DC voltage excitation to the primary side of the electromagnetic voltage transformer, apply AC voltage excitation to the primary side, measure the voltage and current on the secondary side, calculate the saturation point, and obtain the saturation point U under AC voltage. bh0 ;

[0020] Step 2: While applying a given DC voltage excitation value to the primary side of the electromagnetic voltage transformer, simultaneously apply an AC voltage excitation value to the primary side, wherein the applied DC voltage is U. DCThe applied AC voltage is measured at points according to a preset selection principle, up to the rated voltage of the equipment at the rated voltage factor. Voltage and current are measured on the secondary side to calculate the saturation point, yielding the DC component U. DC The saturation point U below bh1 ;

[0021] Step 3: Combine the saturation point under AC voltage with the DC component U DC By comparing and analyzing the saturation point under different conditions, the influence of this DC component on the saturation characteristics of the electromagnetic voltage transformer can be determined, that is, the influence of this DC component U... DC The saturation point offset rate q is calculated as follows:

[0022] q=(U nh0 -U nh1 ) / U bh0 ×100%.

[0023] The preset point selection principle is as follows: the rated voltage of the electromagnetic voltage transformer is Un, and the rated voltage factor is denoted as F. Let U dn =Un-U DC The applied AC voltage is denoted as U. AC ,but

[0024]

[0025] Compared with the prior art, the beneficial effects of the present invention are that, through the application of the method of the present invention, the influence of different DC components on the saturation characteristics of electromagnetic voltage transformers can be analyzed, which can guide the selection, operation and maintenance strategies of electromagnetic voltage transformers, thereby preventing the occurrence of electromagnetic voltage transformer failures, improving equipment safety, and further enhancing the safe and reliable operation level of the power grid. Attached Figure Description

[0026] Figure 1 The flowchart shown is a method for detecting and analyzing the saturation characteristics of an electromagnetic voltage transformer according to the present invention.

[0027] Figure 2 The diagram shown is a structural diagram of an electromagnetic voltage transformer saturation characteristic detection system according to the present invention. Detailed Implementation

[0028] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0029] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0030] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when used in this specification, the words “comprising” and / or “including” indicate the presence of features, steps, operations, parts or modules, components and / or combinations thereof.

[0031] This invention provides a method for detecting and analyzing the saturation characteristics of an electromagnetic voltage transformer that takes into account the DC component.

[0032] In specific implementation, the method of this invention, for the electromagnetic voltage transformer test sample, firstly, without applying DC voltage excitation to the primary side, measures and calculates the saturation point Ubh0 under AC voltage; secondly, with a given value of DC voltage excitation applied to the primary side, the saturation point Ubh1 under the DC component UDC is obtained; finally, a saturation point comparison analysis is performed, and the saturation point offset rate q under the DC component UDC is calculated, thereby conducting an analysis of the influence of different DC components on the saturation characteristics of the electromagnetic voltage transformer.

[0033] like Figure 1 As shown, the present invention provides a method for detecting and analyzing the saturation characteristics of an electromagnetic voltage transformer, comprising the following steps:

[0034] Step 1: Without applying DC voltage excitation to the primary side of the electromagnetic voltage transformer, apply AC voltage excitation to the primary side, measure the voltage and current on the secondary side, calculate the saturation point, and obtain the saturation point U under AC voltage. bh0 ;

[0035] Step 2: While applying a given DC voltage excitation value to the primary side of the electromagnetic voltage transformer, simultaneously apply an AC voltage excitation value to the primary side, wherein the applied DC voltage is U. DC The applied AC voltage is measured at points according to a preset selection principle, up to the rated voltage of the equipment at the rated voltage factor. Voltage and current are measured on the secondary side to calculate the saturation point, yielding the DC component U. DC The saturation point U below bh1 ;

[0036] Step 3: Combine the saturation point under AC voltage with the DC component U DC By comparing and analyzing the saturation point under different conditions, the influence of this DC component on the saturation characteristics of the electromagnetic voltage transformer can be determined, that is, the influence of this DC component U... DC The saturation point offset rate q is calculated as follows:

[0037] q=(U bh0 -U bh1) / U bh0 ×100%.

[0038] The preset point selection principle is as follows: the rated voltage of the electromagnetic voltage transformer is Un, and the rated voltage factor is denoted as F. Let U dn =Un-U DC The applied AC voltage is denoted as U. AC ,but

[0039]

[0040] like Figure 2 As shown, the present invention provides an electromagnetic voltage transformer saturation characteristic detection system, which includes a DC voltage output unit, an AC voltage output unit, and a voltage and current measurement unit.

[0041] The DC voltage output unit is used to apply DC voltage excitation to the electromagnetic voltage transformer;

[0042] The AC voltage output unit is used to apply AC voltage excitation to the electromagnetic voltage transformer;

[0043] The voltage and current measurement unit is used to measure the secondary voltage and current of the electromagnetic voltage transformer.

[0044] The DC voltage output unit, AC voltage output unit, and voltage and current measurement unit perform saturation characteristic detection of the electromagnetic voltage transformer according to the following steps:

[0045] Step 1: Without applying DC voltage excitation to the primary side of the electromagnetic voltage transformer, apply AC voltage excitation to the primary side, measure the voltage and current on the secondary side, calculate the saturation point, and obtain the saturation point U under AC voltage. bh0 ;

[0046] Step 2: While applying a given DC voltage excitation value to the primary side of the electromagnetic voltage transformer, simultaneously apply an AC voltage excitation value to the primary side, wherein the applied DC voltage is U. DC The applied AC voltage is measured at points according to a preset selection principle, up to the rated voltage of the equipment at the rated voltage factor. Voltage and current are measured on the secondary side to calculate the saturation point, yielding the DC component U. DC The saturation point U below bh1 ;

[0047] Step 3: Combine the saturation point under AC voltage with the DC component U DC By comparing and analyzing the saturation point under different conditions, the influence of this DC component on the saturation characteristics of the electromagnetic voltage transformer can be determined, that is, the influence of this DC component U... DC The saturation point offset rate q is calculated as follows:

[0048] q=(U bh0 -U bh1 ) / U nh0 ×100%.

[0049] The preset point selection principle is as follows: the rated voltage of the electromagnetic voltage transformer is Un, and the rated voltage factor is denoted as F. Let U dn =Un-U DC The applied AC voltage is denoted as U. AC ,but

[0050]

[0051] It should be noted that any technical solutions not detailed in this application employ publicly known technologies.

[0052] The above description is only a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for detecting and analyzing the saturation characteristics of an electromagnetic voltage transformer, characterized in that, Includes the following steps: Step 1: Without applying DC voltage excitation to the primary side of the electromagnetic voltage transformer, apply AC voltage excitation to the primary side, measure the voltage and current on the secondary side, calculate the saturation point, and obtain the saturation point U under AC voltage. bh0 ; Step 2: While applying a given DC voltage excitation value to the primary side of the electromagnetic voltage transformer, simultaneously apply an AC voltage excitation value to the primary side, wherein the applied DC voltage is U. DC The applied AC voltage is measured at points according to a preset selection principle, up to the rated voltage of the equipment at the rated voltage factor. Voltage and current are measured on the secondary side to calculate the saturation point, yielding the DC component U. DC The saturation point U below bh1 ; Step 3: Combine the saturation point under AC voltage with the DC component U DC By comparing and analyzing the saturation point under different conditions, the influence of this DC component on the saturation characteristics of the electromagnetic voltage transformer is obtained, that is, the influence of this DC component U... DC The saturation point offset rate q is calculated as follows: ； The preset point selection principle is as follows: the rated voltage of the electromagnetic voltage transformer is Un, and the rated voltage factor is denoted as F. Let U dn =Un-U DC The applied AC voltage is denoted as U. AC ,but 。 2. A system for detecting the saturation characteristics of an electromagnetic voltage transformer, characterized in that, Includes a DC voltage output unit, an AC voltage output unit, and voltage and current measurement units; The DC voltage output unit is used to apply DC voltage excitation to the electromagnetic voltage transformer; The AC voltage output unit is used to apply AC voltage excitation to the electromagnetic voltage transformer; The voltage and current measurement unit is used to measure the secondary voltage and current of the electromagnetic voltage transformer. The DC voltage output unit, AC voltage output unit, and voltage and current measurement unit perform saturation characteristic detection of the electromagnetic voltage transformer according to the following steps: Step 1: Without applying DC voltage excitation to the primary side of the electromagnetic voltage transformer, apply AC voltage excitation to the primary side, measure the voltage and current on the secondary side, calculate the saturation point, and obtain the saturation point U under AC voltage. bh0 ; Step 2: While applying a given DC voltage excitation value to the primary side of the electromagnetic voltage transformer, simultaneously apply an AC voltage excitation value to the primary side, wherein the applied DC voltage is U. DC The applied AC voltage is measured at points according to a preset selection principle, up to the rated voltage of the equipment at the rated voltage factor. Voltage and current are measured on the secondary side to calculate the saturation point, yielding the DC component U. DC The saturation point U below bh1 ; Step 3: Combine the saturation point under AC voltage with the DC component U DC By comparing and analyzing the saturation point under different conditions, the influence of this DC component on the saturation characteristics of the electromagnetic voltage transformer is obtained, that is, the influence of this DC component U... DC The saturation point offset rate q is calculated as follows: ； The preset point selection principle is as follows: the rated voltage of the electromagnetic voltage transformer is Un, and the rated voltage factor is denoted as F. Let U dn =Un-U DC The applied AC voltage is denoted as U. AC ,but 。

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