CN112051526B - A test platform and method for testing excitation characteristics of a transformer model - Google Patents

Abstract

The invention relates to a test platform and a method for testing excitation characteristics of a transformer model, wherein the test platform comprises a transformer model, an alternating current power supply, a resistor, a voltage regulator, a first power analyzer, a second linkage switch, a third linkage switch and a current transformer; the alternating current power supply, the resistor, the voltage regulator, the first power analyzer and the primary winding of the transformer model are sequentially connected in series to form a primary loop, the second power analyzer and the secondary winding of the transformer model are connected in series to form a secondary loop, and the current transformer is used for measuring current data of the primary loop and transmitting the current data to the second power analyzer. The test platform for testing the excitation characteristics of the transformer model provided by the invention not only can obtain the magnetic performance data of the transformer through measurement, but also can truly reflect the electromagnetic performance of the transformer in the actual working state, thereby being beneficial to improving the electromagnetic analysis and the optimal design of the transformer product.

Description

A test platform and method for testing excitation characteristics of transformer models

technical field

The invention relates to the technical field of transformers, and more specifically, to a test platform and method for testing excitation characteristics of transformer models.

Background technique

The iron core in a large power transformer is made of laminated oriented silicon steel sheets, and the problems of no-load loss, no-load current, stray loss, and local overheating in different forms of iron cores are key issues in the design of power transformers. A large number of research results have shown that whether it is the electromagnetic field distribution in the magnetic performance material or the loss distribution, the accuracy and effectiveness of the results depend on the electromagnetic performance of the magnetic material in the actual working state of the transformer after the core is stacked. The electromagnetic performance data provided by electrical material suppliers is usually measured under the conditions specified in the standard. There is a seam form in the actual transformer core, that is, there is an air gap at the seam, which makes it impossible for designers to accurately calculate the magnetic field and loss distribution of the power transformer core.

Contents of the invention

In view of this, the object of the present invention is to provide a test platform and method for testing the excitation characteristics of a transformer model, aiming at solving the problems existing in the prior art.

According to the first aspect of the present invention, there is provided a test platform for testing the excitation characteristics of a transformer model, including a transformer model, an AC power supply, a resistor, a voltage regulator, a first power analyzer, a second power analyzer, a second A linkage switch, a third linkage switch and a current transformer;

The AC power supply, the resistor, the voltage regulator, the first power analyzer, and the primary winding of the transformer model are sequentially connected in series to form a primary loop, and the first moving contact of the second linkage switch is connected to the regulator of the voltage regulator. Between the pressure terminal and the first power analyzer, the second moving contact of the second linkage switch is connected between the AC power supply and the primary winding;

The second power analyzer is connected in series with the secondary winding of the transformer model to form a secondary loop, and the first moving contact of the third linkage switch is connected to the first pole of the secondary winding and the second Between the first poles of the power analyzer, the second movable contact of the third linkage switch is connected between the second pole of the secondary winding and the second pole of the second power analyzer;

The wire between the first movable contact of the second linkage switch and the first power analyzer passes through the induction coil of the current transformer, and the output terminal of the current transformer is connected to the second power analyzer. connected to the instrument.

Preferably, the primary circuit also includes a first linkage switch and a voltmeter;

The first moving contact of the first linkage switch is connected between the AC power supply and the resistor, and the second moving contact of the first linkage switch is connected between the AC power supply and the second linkage between the second moving contacts of the switch;

The first pole of the voltmeter is connected between the voltage regulating terminal of the voltage regulator and the first moving contact of the second linkage switch, and the second pole of the voltmeter is connected to the first linkage Between the second moving contact of the switch and the second moving contact of the second linkage switch.

Preferably, the transformer model adopts Epstein square core models with different joint forms.

According to a second aspect of the present invention, a method for testing excitation characteristics of a transformer model is provided, comprising:

Step 1. Build the test platform as mentioned above;

Step 2, verifying the measurement circuit of the test platform;

Step 3, demagnetizing the transformer model;

Step 4, closing the first linkage switch, the second linkage switch and the third linkage switch, measuring and recording the excitation current data, voltage waveform data and loss data of the transformer model;

Step 5. Draw the magnetization characteristic curve and the loss curve according to the data recorded in the step 4, and perform the fitting calculation of the loss according to the measured curve data.

Preferably, in the step 2, verify the measurement circuit of the test platform, if it is normal, go to step 3, if not, check the measurement circuit and re-verify after troubleshooting until it is normal.

Preferably, said step two includes:

Close the first linkage switch of the primary circuit, disconnect the second linkage switch, boost the voltage regulator, check the reading of the voltmeter in the primary circuit, if the reading of the voltmeter gradually increases If it is large, it means that the power supply is normal and the test can be carried out.

Preferably, said step 2 also includes:

Return the voltage regulator to zero, close the first linkage switch and the second linkage switch, disconnect the third linkage switch, check the current reading of the first power analyzer, if the current reading is zero, then It shows that the measurement circuit is normal; boost the voltage regulator to the rated voltage of the transformer model, record the current and voltage data collected by the first power analyzer, close the third linkage switch, and record the second The current and voltage data collected by the power analyzer, compare the current and voltage data collected twice, and if the results are the same, the test can continue.

Preferably, said step three includes:

Return the voltage regulator to zero, disconnect the third linkage switch, close the first linkage switch and the second linkage switch, short-circuit the current input terminal on the first power analyzer, and the voltage regulator Boost the voltage of the transformer so that the core magnetic density of the transformer model reaches above 2.0T, and then step down the voltage to zero.

Preferably, in the step four, close the first linkage switch, the second linkage switch and the third linkage switch, adjust the voltage regulator according to the estimated voltage data, step up the voltage, and use the first power analyzer and a second power analyzer to measure and record the excitation current data, voltage waveform data and loss data of the transformer model; wherein, the estimated voltage data is the threshold voltage when the iron core magnetic density of the transformer model reaches 2.0T or more .

Preferably, said step four also includes:

According to the average value and effective value of each voltage point during the boosting process, the distortion rate of the voltage is calculated. When the waveform coefficient exceeds 1.5%, the boosting is stopped; then the voltage is gradually lowered and the corresponding voltage points are measured and recorded. The repeatability of test data.

The test platform and method for testing the excitation characteristics of the transformer model provided by the present invention can test the excitation characteristics of the iron core in the transformer model, and can separate the loss of the iron core joint area and the column yoke area; it can measure the transformer model at different saturation levels Under the induced voltage, excitation current and corresponding waveform; the magnetization characteristic curve and loss curve of the iron core in the transformer model under different saturation conditions can be obtained. Not only can the magnetic performance data of the transformer be obtained through measurement, but it can also truly reflect the electromagnetic performance of the transformer under actual working conditions, which is conducive to improving the electromagnetic analysis and optimal design of transformer products.

Description of drawings

The above and other objects, features and advantages of the present invention will be more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings.

Fig. 1 shows a circuit structure diagram of a test platform for testing excitation characteristics of a transformer model according to an embodiment of the present invention.

In the figure: transformer model 1, primary winding 2, secondary winding 3, AC power supply 4, resistor 5, voltage regulator 6, voltmeter 7, first power analyzer 8, second power analyzer 9, current transformer 10. A first linkage switch 11 , a second linkage switch 12 , and a third linkage switch 13 .

Detailed ways

Various embodiments of the invention will be described in more detail below with reference to the accompanying drawings. In the various drawings, the same elements are denoted by the same or similar reference numerals. For the sake of clarity, various parts in the drawings have not been drawn to scale.

With reference to Fig. 1, the present invention provides a kind of test platform for transformer model excitation characteristic test, described test platform comprises transformer model 1, AC power supply 4, resistor 5, voltage regulator 6, the first power analyzer 8, the first Two power analyzers 9 , a second linkage switch 12 , a third linkage switch 13 and a current transformer 10 .

The primary winding 2 of the AC power supply 4, resistor 5, voltage regulator 6, first power analyzer 8 and transformer model 1 is connected in series in sequence to form a primary loop, and the first moving contact of the second linkage switch 12 is connected to the voltage regulating Between the voltage regulating end of the device 6 and the first power analyzer 8, the second moving contact of the second linkage switch 12 is connected between the AC power supply 4 and the primary winding 2;

The second power analyzer 9 is connected in series with the secondary winding 3 of the transformer model 1 to form a secondary circuit, and the first movable contact of the third linkage switch 13 is connected to the first pole of the secondary winding 3 and the second power analyzer 9, the second moving contact of the third linkage switch 13 is connected between the second pole of the secondary winding 3 and the second pole of the second power analyzer 9;

The wire between the first moving contact of the second linkage switch 13 and the first power analyzer 9 passes through the induction coil of the current transformer 10 , and the output terminal of the current transformer 10 is connected with the second power analyzer 9 .

The primary circuit also includes a first linkage switch 11 and a voltmeter 7, the first movable contact of the first linkage switch 11 is connected between the AC power supply 4 and the resistor 5, the second movable contact of the first linkage switch 11 The point is connected between the AC power source 4 and the second moving contact of the second linkage switch 12;

The first pole of the voltmeter 7 is connected between the voltage regulating terminal of the voltage regulator 6 and the first moving contact of the second linkage switch 12, and the second pole of the voltmeter 7 is connected to the second moving contact of the first linkage switch 11. between the contact and the second moving contact of the second linkage switch 12.

In this embodiment, the transformer model 1 adopts Epstein square core models with different joint forms.

The present invention also provides a method for testing the excitation characteristics of a transformer model, including:

Step 1. Build the above-mentioned test platform for testing the excitation characteristics of the transformer model.

According to the circuit structure diagram shown in Figure 1, a test platform for testing the excitation characteristics of the transformer model is built. Among them, the first power analyzer 8 is used to measure the primary winding 2 of the transformer model 1, the second power analyzer 9 is used to measure the secondary winding 3 of the transformer model 1, and the third linkage switch 13 is used to close or disconnect the measurement transformer The connection between the secondary winding 3 of model 1 and the second power analyzer 9 .

Step 2, verify the measurement circuit of the test platform.

In this step, verify the measurement circuit of the test platform, if it is normal, go to step 3, if not, check the measurement circuit and re-verify after troubleshooting until it is normal.

The specific operation process of the measurement circuit of the verification test platform is as follows:

Close the first linkage switch 11, disconnect the second linkage switch 12, boost the voltage regulator 6, check the reading of the voltmeter 7, if the reading of the voltmeter 7 gradually increases, it means that the power supply is normal, and the test can be carried out. Return the voltage regulator 6 to zero, close the first linkage switch 11 and the second linkage switch 12, open the third linkage switch 13, check the current reading of the first power analyzer 8, if the current reading is zero, it indicates the measurement circuit normal. Boost the voltage regulator 6 to the rated voltage of the transformer model 1, record the current and voltage data collected by the first power analyzer 8, close the third linkage switch 13, record the current and voltage data collected by the second power analyzer 9, Compare the current and voltage data from the two acquisitions, and if the results are the same, you can continue the experiment.

Among them, the first power analyzer 8 measures the current and voltage data of the primary winding 2 of the transformer model 1; the second power analyzer 9 measures the voltage data of the secondary winding 3 of the transformer model 1, and measures the primary winding 2 of the transformer model 1 through the current transformer 10 Current data for winding 2. The primary winding 2 and the secondary winding 3 of the transformer model 1 in this embodiment have the same number of turns.

Step 3, demagnetize the transformer model.

Before testing the excitation characteristics of the transformer model, it is necessary to demagnetize the transformer model 1. The specific operation process is as follows:

Return the voltage regulator 6 to zero, disconnect the third linkage switch 13, close the first linkage switch 11 and the second linkage switch 12, short-circuit the current input terminal on the first power analyzer 8, and boost the voltage of the voltage regulator 6, Make the iron core flux density of transformer model 1 reach above 2.0T, and then step down to zero. Note that the step-down should be continuous, steady and slow.

Step 4, closing the first linkage switch, the second linkage switch and the third linkage switch, measuring and recording the excitation current data, voltage waveform data and loss data of the transformer model.

The specific operation of this step is as follows:

Close the first linkage switch 11, the second linkage switch 12 and the third linkage switch 13, adjust the voltage regulator 6 according to the estimated voltage data, gradually increase the voltage, measure and record with the first power analyzer 8 and the second power analyzer 9 Exciting current data, voltage waveform data and loss data of transformer model 1; wherein, the estimated voltage data is the threshold voltage when the iron core flux density of transformer model 1 reaches 2.0T or more.

According to the average value and effective value of each voltage point during the boosting process, the distortion rate of the voltage is calculated. When the waveform coefficient exceeds 1.5%, the boosting is stopped; then the voltage is gradually lowered and the corresponding voltage points are measured and recorded. The repeatability of test data.

Among them, the voltage points selected during the boosting process should be uniform, so as to facilitate the drawing of curves based on the recorded data in the later stage.

Step 5. Draw the magnetization characteristic curve and the loss curve according to the data recorded in the step 4, and perform the fitting calculation of the loss according to the measured curve data.

In this step, the data recorded in the step 4 is processed, respectively included in the corresponding table, the magnetization characteristic curve (B-H curve) and the loss curve (B-P curve) are drawn, and the loss is fitted according to the measured curve data calculate.

The test platform for transformer model excitation characteristic test of the present invention can measure the no-load loss and no-load current of the transformer model, based on the test platform can analyze the loss distribution characteristics and excitation characteristics of the transformer core in different joint forms, through The test results of the transformer core model can be transferred to the data support for the calculation of transformer no-load loss and no-load current.

The test platform for testing the excitation characteristics of the transformer model provided by the invention can test the excitation characteristics of the iron core in the transformer model, and can separate the loss of the iron core joint area and the column yoke area; it can measure the loss of the transformer model under different saturation degrees Induced voltage, excitation current and corresponding waveforms; the magnetization characteristic curve and loss curve of the iron core in the transformer model under different saturation conditions can be obtained. Not only can the magnetic performance data of the transformer be obtained through measurement, but it can also truly reflect the electromagnetic performance of the transformer under actual working conditions, which is conducive to improving the electromagnetic analysis and optimal design of transformer products.

It should be noted that in this document, relational terms such as first and second etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is a relationship between these entities or operations. There is no such actual relationship or order between them. Furthermore, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus comprising a set of elements includes not only those elements, but also includes elements not expressly listed. other elements of or also include elements inherent in such a process, method, article, or device. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising said element.

Finally, it should be noted that obviously, the above-mentioned embodiments are only examples for clearly illustrating the present invention, rather than limiting the implementation. For those of ordinary skill in the art, other changes or changes in different forms can be made on the basis of the above description. It is not necessary and impossible to exhaustively list all the implementation manners here. However, the obvious changes or variations derived therefrom are still within the protection scope of the present invention.

Claims (5)

1. A method for transformer model excitation characteristic test, is characterized in that, comprises: Step 1. Build a test platform, which includes a transformer model, an AC power supply, a resistor, a voltage regulator, a first power analyzer, a second power analyzer, a second linkage switch, a third linkage switch and a current transformer ; The primary winding of the AC power supply, resistor, voltage regulator, first power analyzer and transformer model are connected in series to form a primary loop, and the first moving contact of the second linkage switch is connected to the voltage regulator Between the voltage regulating terminal and the first power analyzer, the second moving contact of the second linkage switch is connected between the AC power supply and the primary winding; the second power analyzer and the The secondary winding of the transformer model is connected in series to form a secondary loop, and the first movable contact of the third linkage switch is connected between the first pole of the secondary winding and the first pole of the second power analyzer, The second moving contact of the third linkage switch is connected between the second pole of the secondary winding and the second pole of the second power analyzer; the first moving contact of the second linkage switch The wire with the first power analyzer passes through the induction coil of the current transformer, and the output end of the current transformer is connected to the second power analyzer; The primary circuit also includes a first linkage switch and a voltmeter; the first moving contact of the first linkage switch is connected between the AC power supply and the resistor, and the second movement contact of the first linkage switch The contact is connected between the AC power supply and the second moving contact of the second linkage switch; the first pole of the voltmeter is connected to the voltage regulating terminal of the voltage regulator and the second linkage switch Between the first moving contacts of the voltmeter, the second pole of the voltmeter is connected between the second moving contacts of the first linkage switch and the second movement contacts of the second linkage switch; The transformer model adopts Epstein square circle iron core models with different joint forms; Step 2, verifying the measurement circuit of the test platform; Step 3: Demagnetize the transformer model; reset the voltage regulator to zero, disconnect the third linkage switch, close the first linkage switch and the second linkage switch, and short-circuit the first power The current input terminal on the analyzer, the voltage regulator boosts the voltage so that the iron core magnetic density of the transformer model reaches more than 2.0T, and then gradually reduces the voltage to zero; Step 4. Close the first linkage switch, the second linkage switch and the third linkage switch, measure and record the excitation current data, voltage waveform data and loss data of the transformer model; close the first linkage switch, the second linkage switch The linkage switch and the third linkage switch adjust the voltage regulator according to the estimated voltage data, gradually boost the voltage, and use the first power analyzer and the second power analyzer to measure and record the excitation current data and voltage of the transformer model Waveform data and loss data; wherein, the estimated voltage data is the threshold voltage when the iron core magnetic density of the transformer model reaches above 2.0T; Step 5. Draw the magnetization characteristic curve and the loss curve according to the data recorded in the step 4, and perform the fitting calculation of the loss according to the measured curve data. 2. the method for transformer model excitation characteristic test according to claim 1, is characterized in that, in described step 2, verify the measurement circuit of described test platform, if normal, then enter step 3, if not normal, Then check the measurement circuit and re-verify after troubleshooting until it is normal. 3. the method for transformer model excitation characteristic test according to claim 2, is characterized in that, described step 2 comprises: Close the first linkage switch of the primary circuit, disconnect the second linkage switch, boost the voltage regulator, check the reading of the voltmeter in the primary circuit, if the reading of the voltmeter gradually increases If it is large, it means that the power supply is normal and the test can be carried out. 4. the method for transformer model excitation characteristic test according to claim 3, is characterized in that, described step 2 also comprises: Return the voltage regulator to zero, close the first linkage switch and the second linkage switch, disconnect the third linkage switch, check the current reading of the first power analyzer, if the current reading is zero, then It shows that the measurement circuit is normal; boost the voltage regulator to the rated voltage of the transformer model, record the current and voltage data collected by the first power analyzer, close the third linkage switch, and record the second The current and voltage data collected by the power analyzer, compare the current and voltage data collected twice, and if the results are the same, the test can continue. 5. the method for transformer model excitation characteristic test according to claim 1, is characterized in that, described step 4 also comprises: According to the average value and effective value of each voltage point during the boosting process, the distortion rate of the voltage is calculated. When the waveform coefficient exceeds 1.5%, the boosting is stopped; then the voltage is gradually lowered and the corresponding voltage points are measured and recorded. The repeatability of test data.