CN117192361A - Multi-rubber molded stator bar insulation sine wave to ground and medium-frequency electric aging test method for hydraulic generator - Google Patents
Multi-rubber molded stator bar insulation sine wave to ground and medium-frequency electric aging test method for hydraulic generator Download PDFInfo
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- 230000032683 aging Effects 0.000 title claims abstract description 62
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- 230000015556 catabolic process Effects 0.000 claims abstract description 59
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- 239000003292 glue Substances 0.000 claims abstract description 14
- 230000008569 process Effects 0.000 claims description 12
- 239000004020 conductor Substances 0.000 claims description 6
- 239000010445 mica Substances 0.000 claims description 5
- 229910052618 mica group Inorganic materials 0.000 claims description 5
- 238000003825 pressing Methods 0.000 claims description 5
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical group [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 4
- 238000004364 calculation method Methods 0.000 claims description 4
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 3
- 229910052782 aluminium Inorganic materials 0.000 claims description 3
- 238000007664 blowing Methods 0.000 claims description 3
- 229910052802 copper Inorganic materials 0.000 claims description 3
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- 238000007705 chemical test Methods 0.000 claims 1
- 230000035882 stress Effects 0.000 abstract description 6
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- 230000010287 polarization Effects 0.000 description 4
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Abstract
The invention discloses a hydro-generator multi-rubber molded stator bar insulation sine wave and intermediate frequency electrical aging test method, and relates to a hydro-generator multi-rubber molded stator bar insulation sine wave and intermediate frequency electrical aging test method. The invention provides an operation flow of an electric aging test, test voltage and test medium under the conditions of sine wave, high frequency and high voltage of the insulating structure of the multi-glue molded stator bar, and fills the current situation that no method can be used for evaluating the reliability of the insulating structure of the stator bar of the generator with special purposes in China; according to a large number of high-frequency electric aging test experience carried out in a laboratory, electric aging test methods under different frequencies and voltages are disclosed, and finally, the aim of insulation electric breakdown of the stator bar under the conditions of high frequency and high electric stress is fulfilled, and the occurrence of high-resistance anti-corona layers and main insulation thermal breakdown is effectively prevented. The invention is applied to the technical field of electric aging tests of sine waves of insulating structures of stator bars at different frequencies.
Description
Technical Field
The invention relates to a hydro-generator multi-rubber molded stator bar insulation sine wave to ground and medium-frequency electric aging test method.
Background
The multi-gel molded stator bar of the large and medium-sized hydraulic generator mainly bears the action of an insulation degradation mechanism taking an electric factor as a main factor in the whole life cycle operation process, and a plurality of test line bar insulation performance test methods including a power frequency voltage withstand test, a breakdown test, a dielectric loss factor test, a partial discharge test and the like are formulated, wherein the electric aging test is a means for rapidly evaluating the ground insulation operation life under the condition of reasonably improving the electric stress, and is an effective means for estimating the operation life of the generator relatively accurately. At present, large and medium-sized hydraulic generators (including pumped storage generator motors), steam turbine generators and nuclear generators which are installed in China all operate under sine waves and power frequency 50Hz voltage, and the conducted stator bar insulation against ground electric aging test is also usually carried out under the power frequency 50Hz condition.
In recent years, with the continuous development of generator technology, many motors adopting novel structures propose different voltage operation schemes, for example, novel impact generators for hydropower, high-speed permanent magnet generators and pulse generators need to operate in the voltage condition of sine waves and medium-level frequencies (180 Hz-200 Hz) for a long time/a short time, and corresponding stator bar insulation structures of the motors also need to bear the influence of the stresses different from the sine waves and the power frequency voltages. Under the condition that the externally applied voltage is kept unchanged, the frequency is increased to greatly influence the service life of the insulating structure of the stator bar, on one hand, the sine period applied to the insulating structure is shortened due to the increase of the frequency, so that the internal partial discharge activity of the ground insulation is more serious; on the other hand, the high-frequency heating phenomenon is caused by the fact that the current of the resistive component of the high-resistance anti-corona layer is increased due to the rapid change of the frequency of the electric field, and the improvement of the frequency has a larger influence on the insulating structure of the wire rod, particularly the structure of the high-resistance anti-corona layer. Unlike the power frequency sine wave electrical aging test performed in an air medium, the continuous sine wave and intermediate frequency electrical aging test performed in the air medium can cause the anti-corona layer to overheat and easily generate rapid thermal breakdown, and the life expectancy of the insulation of the stator bar to the ground under the sine wave and high voltage test conditions can not be effectively checked by changing the electrical stress degradation mechanism of the electrical aging test, so that necessary verification data can not be provided for the design of the novel generator, and the safe and reliable operation of the special-purpose generator sets can be influenced.
Disclosure of Invention
The invention aims to provide a hydro-generator multi-gel molded stator bar insulation sine wave to ground and medium frequency electric aging test method.
The invention relates to a hydro-generator multi-rubber molded stator bar insulation sine wave to ground and medium-frequency electric aging test method, which comprises the following steps:
1. solving the breakdown life of the sine wave and the power frequency of 50Hz under the voltage of 2.17 times of rated line voltage of the multi-rubber molded stator bar, and recording as L 2.17-50 ；
2. Solving the breakdown life of the sine wave and 100Hz power frequency of the multi-rubber molded stator bar under 2.0 times of rated line voltage, and recording as L 2.0-100 ；
3. The breakdown life of the sine wave and 150Hz power frequency of the multi-rubber molded stator bar under the rated line voltage of 1.6 times is calculated and recorded as L 1.6-150 ；
4. The breakdown life of the sine wave and the intermediate frequency of the multi-rubber molded stator bar under the rated line voltage of 1.4 times is obtained and is recorded as L 1.4-intermediate frequency ；
5. Using formula L 2.17-50 ×50(Hz)＝L 2.17-intermediate frequency X mid-level frequency (Hz), L 2.0-100 ×100(Hz)＝L 2.0-intermediate frequency X mid-level frequency (Hz), L 1.6-150 ×150(Hz)＝L 1.6-intermediate frequency The x mid-level frequency (Hz) calculates the breakdown life L corresponding to 2.17 times rated line voltage, 2 times rated line voltage and 1.6 times rated line voltage at the mid-level frequency respectively 2.17-intermediate frequency 、L 2.0-intermediate frequency 、L 1.6-intermediate frequency ；
6. Using the formula Calculation E 2.17 、E 2.0 、E 1.6 And E is 1.4 The method comprises the steps of carrying out a first treatment on the surface of the E is the field intensity;
7. will [ (L) 2.17-intermediate frequency 、E 2.17 )、(L 1.4-intermediate frequency 、E 1.4 )],[(L 2.0-intermediate frequency 、E 2.0 )、(L 1.4-intermediate frequency 、E 1.4 )],[(L 1.6-intermediate frequency 、E 1.6 )、(L 1.4-intermediate frequency 、E 1.4 )]Three sets of data are respectively brought into the formula l=c×e -n To calculate the coefficient C corresponding to each group of data 1 、n 1 、C 2 、n 2 、C 3 、n 3 ；
8. Using the formulaAnd->Determining breakdown life L extrapolated to rated line voltage 1 、L 2 And L 3 The average of these 3 data is determined +.>The multi-rubber molded stator bar insulation structure is used as the breakdown life of sinusoidal waves and intermediate frequency of the hydro-generator.
The heat conductivity coefficient of the air is about 0.01W/mK to 0.04W/mK, and the heat conductivity coefficient of the transformer oil is about 0.128W/mK; under the condition of uniform electric field, the breakdown field intensity of air is about 3kV/mm, the breakdown field intensity of transformer oil is about 8 kV/mm-24 kV/mm, and under the condition that the relative voltage is not high (not more than 3 times of rated line voltage) and the medium frequency is lower than the medium frequency (200 Hz), the electric aging test is carried out in the transformer oil, so that the phenomena of thermal breakdown and surface flashover and discharge trace are avoided in the whole of the corona prevention area of the test wire rod; however, under relatively high voltage (1.5 times of rated line voltage and above), the electric aging test is carried out in transformer oil to inhibit (can not reflect) the problems of relaxation polarization loss and heating caused by dipole polarization and interface polarization, so that the test is carried out in an air medium as far as possible in the invention, and the service life under medium frequency is calculated by applying a frequency-service life conversion formula so as to improve the test voltage as much as possible, and fully excite the relaxation polarization loss and partial discharge degradation process; in the process of carrying out the electrical aging test under different frequencies, the photon number and the surface temperature of the high-resistance anti-corona area are observed by using an ultraviolet imager and an infrared thermal imager, and the resistance and the temperature characteristics different from sine waves and the power frequency 50Hz electrical aging test, namely the surface conductivity is changed to change the temperature in the test process; by developing electric aging tests under a plurality of voltage points and frequencies, the aim of ensuring that the stator test bar anti-corona area is not damaged in the test process is fulfilled, the optimal parameters of electric aging are determined, the electric stress resistance of the multi-rubber molded stator bar insulation structure of the hydraulic generator is effectively evaluated, and necessary design reference and verification are provided for the hydraulic generator by using a novel impact generator, a high-speed permanent magnet generator and a pulse generator.
The invention has the beneficial effects that:
1. the invention provides an electric aging test method, an operation flow and test voltage and test media of original conversion frequency under the conditions of multi-rubber molded stator bar insulation sine wave and high voltage of 180 Hz-200 Hz of a hydraulic generator, which fills the current situation that no method can be used for evaluating the reliability of the insulation of the stator bar of the generator for special purposes such as sine wave and medium frequency in China, and has important effect on evaluating the deterioration state of the insulation structure of the stator bar of the multi-rubber molded stator bar used for a novel hydraulic generator, a high-speed permanent magnet generator and a pulse generator;
2. according to a large number of sine wave 50Hz, 100Hz, 150Hz, 180 Hz-200 Hz ground insulation electric aging test experiences carried out in a laboratory, electric aging test methods under different frequencies and voltages are disclosed, the breakdown magnitude of intermediate frequency is calculated through a frequency correlation formula and a life extrapolation formula, the goal of obtaining life design parameters of the ground insulation structure is realized, the problem of degradation mechanism change caused by high-resistance corona-prevention layer thermal breakdown is effectively prevented, and the method provided by the invention can be used for clearly testing the electric stress degradation eigenvalue of the stator bar ground insulation structure, so that key references of insulation material selection and insulation structure design are provided in a targeted manner during unit design.
Drawings
FIG. 1 is a flow chart of an electrical aging test of the method of the present invention;
FIG. 2 is a flow chart of a sine wave, 150Hz electrical aging test.
Detailed Description
The technical scheme of the invention is not limited to the specific embodiments listed below, but also includes any combination of the specific embodiments.
The first embodiment is as follows: the method for testing the electric aging of the multi-rubber molded stator bar of the hydraulic generator on the basis of the sine wave and the intermediate frequency of the insulation against the ground in the embodiment is as follows:
1. solving the breakdown life of the sine wave and the power frequency of 50Hz under the voltage of 2.17 times of rated line voltage of the multi-rubber molded stator bar, and recording as L 2.17-50 ；
2. Solving the breakdown life of the sine wave and 100Hz power frequency of the multi-rubber molded stator bar under 2.0 times of rated line voltage, and recording as L 2.0-100 ；
3. The breakdown life of the sine wave and 150Hz power frequency of the multi-rubber molded stator bar under the rated line voltage of 1.6 times is calculated and recorded as L 1.6-150 ；
4. The breakdown life of the sine wave and the intermediate frequency of the multi-rubber molded stator bar under the rated line voltage of 1.4 times is obtained and is recorded as L 1.4-intermediate frequency ；
5. Using formula L 2.17-50 ×50(Hz)＝L 2.17-intermediate frequency X mid-level frequency (Hz), L 2.0-100 ×100(Hz)＝L 2.0-intermediate frequency X mid-level frequency (Hz), L 1.6-150 ×150(Hz)＝L 1.6-intermediate frequency The x mid-level frequency (Hz) calculates the breakdown life L corresponding to 2.17 times rated line voltage, 2 times rated line voltage and 1.6 times rated line voltage at the mid-level frequency respectively 2.17-intermediate frequency 、L 2.0-intermediate frequency 、L 1.6-intermediate frequency ；
6. Using the formula Calculation E 2.17 、E 2.0 、E 1.6 And E is 1.4 The method comprises the steps of carrying out a first treatment on the surface of the E is the field intensity;
7. will [ (L) 2.17-intermediate frequency 、E 2.17 )、(L 1.4-intermediate frequency 、E 1.4 )]，[(L 2.0-intermediate frequency 、E 2.0 )、(L 1.4-intermediate frequency 、E 1.4 )]，[(L 1.6-intermediate frequency 、E 1.6 )、(L 1.4-intermediate frequency 、E 1.4 )]Three sets of data are respectively brought into the formula l=c×e -n To calculate the coefficient C corresponding to each group of data 1 、n 1 、C 2 、n 2 、C 3 、n 3 ；
8. Using the formulaAnd->Determining breakdown life L extrapolated to rated line voltage 1 、L 2 And L 3 The average of these 3 data is determined +.>The multi-rubber molded stator bar insulation structure is used as the breakdown life of sinusoidal waves and intermediate frequency of the hydro-generator.
The second embodiment is as follows: the first difference between this embodiment and the specific embodiment is that: the multi-glue molded stator bar is a stator test bar which is manufactured by adopting a multi-glue molded insulation pressing process and only comprises a straight line part, a wire of the manufactured stator test bar is a copper conductor/aluminum conductor, an insulation mica tape and a low-resistance/high-resistance corona-resistant tape are wrapped outside the wire, and the manufactured stator test bar is molded by compression molding and solidification. The other is the same as in the first embodiment.
And a third specific embodiment: this embodiment differs from the first or second embodiment in that: l (L) 2.17-50 The method for solving the (3): carrying out sine wave and 50Hz power frequency electric aging test under the conditions of 2.17 times rated line voltage, air medium and continuous and uninterrupted high voltage application until the multi-glue mould pressing stator bar breaks down to obtain breakdown life, which is recorded as L 2.17-50 . The other embodiments are the same as those of the first or second embodiment.
The specific embodiment IV is as follows: this embodiment differs from one of the first to third embodiments in that: l (L) 2.0-100 The method for solving the (3): sine wave and 100Hz electric aging tests are carried out under the conditions of 2 times rated line voltage and air medium, 8 hours of electric aging tests are carried out every time, the test is stopped for 8 hours, and the test is repeated according to the rule until the multi-glue molded stator bar breaks down, so that the breakdown life is obtained and is recorded as L 2.0-100 . The other is the same as in one of the first to third embodiments.
Fifth embodiment: this embodiment differs from one to four embodiments in that: l (L) 1.6-150 The method for solving the (3): performing sine wave and 150Hz electric aging test under the conditions of 1.6 times rated line voltage and air medium, blowing the surface of the high-resistance anti-corona area of the wire rod by using a blower with the wind speed of 3.5 m/s, observing the surface temperature of the high-resistance anti-corona area by using an infrared thermal imager or an ultraviolet imager, continuously testing under the condition that the hottest point temperature of the surface of the high-resistance anti-corona area is not more than 90 ℃ until the multi-glue molded stator wire rod breaks down, obtaining the breakdown life, and recording as L 1.6-150 . The others are the same as in one to one fourth embodiments.
Specific embodiment six: this embodiment differs from one of the first to fifth embodiments in that: the linear distance between the blower and the surface of the high-resistance anti-corona area is less than 1 meter. The other is the same as in one of the first to fifth embodiments.
Seventh embodiment: this embodiment differs from one of the first to sixth embodiments in that: the linear distance between the infrared thermal imager or the ultraviolet imager and the surface of the high-resistance anti-corona area is less than 1 meter. The others are the same as in one of the first to sixth embodiments.
Eighth embodiment: this embodiment differs from one of the first to seventh embodiments in that: l (L) 1.6-150 In the solving process, when the surface temperature of the high-resistance anti-corona area reaches 90 ℃, the test is stopped immediately, the test is continued after the temperature is reduced to the room temperature, and the test is repeated according to the rule until the multi-rubber mold-pressed stator bar breaks down. The other is the same as in one of the first to seventh embodiments.
Detailed description nine: this embodiment differs from one to eight of the embodiments in that: l (L) 1.4-intermediate frequency The method for solving the (3): immersing the multi-rubber molded stator bar into transformer oil for sine wave and intermediate frequency electric aging test, wherein the test voltage is 1.4 times of rated line voltage, and testing under the condition of continuous uninterrupted operation until the multi-rubber molded stator bar breaks down to obtain the breakdown life, which is recorded as L 1.4-intermediate frequency . The others are the same as in one to eight embodiments.
Detailed description ten: this embodiment differs from one of the first to ninth embodiments in that the intermediate frequency is 180Hz to 200Hz. The other is the same as in one of the embodiments one to nine.
The following examples are used to verify the benefits of the present invention:
example 1
The electrical aging test flow (fig. 1) of this example is: the method comprises the steps of manufacturing a stator straight bar insulation structure of a hydraulic generator by using a multi-glue molding process to serve as a test bar, wherein rated voltage of the test bar is 15kV, single-sided insulation thickness is 3.5mm, and performing electric aging tests of sine waves with middle-level frequencies of 50Hz, 100Hz, 150Hz and 190Hz respectively;
the waveform of the test voltage of the outer Shi Zhengxian wave is approximate to a sine wave, and the ratio of the peak value to the effective value of the sine wave isIs within;
the preparation method of the test wire rod comprises the following steps: according to the insulation structure characteristics of the stator bar of the hydraulic generator, a multi-glue molding insulation pressing process is used for manufacturing a stator test bar (comprising a groove part and an end part) only comprising a straight line part, an end part corner area and an involute structure are not included, a lead of the manufactured stator test bar is a copper conductor, an insulation mica area and a low-resistance/high-resistance anti-corona area are covered outside, wherein part of the insulation mica area and the low-resistance anti-corona area form the groove part of the test bar, and the other part of the insulation mica area and the high-resistance anti-corona area form the end part of the test bar, so that the actual hydraulic generator stator bar is truly simulated in terms of insulation structure, and the reason that the manufactured stator bar only comprises the straight line part is that the electric field distortion of the high-resistance anti-corona area is reduced relative to the real machine bar, and the edge flashover or creepage breakdown of the end area is ensured not to happen when a subsequent blower (such as a high-power axial flow fan) blows the surface of the bar; the molded test bar comprises an integral insulation structure which is the same as that of a true stator bar of the hydraulic generator; the number of the samples under each test voltage is 4, the high voltage is lifted from 0 value until breakdown, wherein the breakdown refers to the breakdown of a groove part, and the breakdown is not the thermal breakdown or the surface flashover of an end part area, so that the average value under each test voltage is obtained;
placing a group of (4) test bars on a dry insulating support frame at equal intervals in parallel, testing under the conditions of 2.17 times rated line voltage (32.55 kV), air medium, continuous uninterrupted sine wave application and 50Hz high voltage according to the basic requirements of NB/T42005 and GB/T7894 standard until the test bars break down, counting time from the time when the externally applied voltage reaches a specified value until the break down time is counted as electrical aging time, calculating the average value of the breakdown life (time) of the 4 test bars, and recording as L 2.17 The method comprises the steps of carrying out a first treatment on the surface of the Test wire rodThe conductor is connected with high voltage to be used as a high-voltage electrode, and the surface of the low-resistance anti-corona layer is wrapped with an aluminum foil electrode or a copper wire to be wound and then grounded to be used as a grounding electrode;
the sample selection principle, electrode treatment mode and wiring mode of the sine wave and 100Hz electric aging test are the same as those of the test method under 50Hz power frequency, the sine wave and 100Hz electric aging test is carried out under the conditions of 2 times rated line voltage (30 kV) and air medium, the time is 8 hours from the time when the externally applied voltage reaches the specified voltage, then the high voltage is removed, the test is suspended for 8 hours, the test is carried out repeatedly according to the rule, the test is carried out until the test bar sample breaks down, the stage when the externally applied voltage reaches the specified value is counted as effective time, the total effective time until the breakdown is counted as electric aging time, the average value of the breakdown life (voltage) of 4 test bars is calculated and is recorded as L 2.0 ；
The sample selection principle, the electrode treatment mode and the wiring mode of the sine wave and 150Hz electric aging test are the same as those of the test method under 50Hz power frequency, and as shown in figure 2, the sine wave and 150Hz electric aging test is carried out under the conditions of 1.6 times (24 kV) rated line voltage and air medium; because the temperatures of the low-resistance anti-corona region, the high-resistance anti-corona region and the low-resistance and high-resistance overlap region are obviously improved compared with 50 Hz-100 Hz in the 150Hz electrical aging test process, if no measures are taken, thermal breakdown occurs under the voltage of 1.6 times (24 kV) rated line, multiple tests are carried out, the ultraviolet photon number and the temperature are monitored by an ultraviolet imager and an infrared imager in the test process, and a method without thermal breakdown is found on the basis of a large number of tests in the early stage. On the basis of summarizing sine wave and different frequency electric aging test experience, determining measures for preventing the high-resistance anti-corona layer from generating thermal breakdown, blowing a blower (such as a high-power axial flow fan) with air quantity not smaller than 3000 cubic meters per hour onto the surface of the high-resistance anti-corona layer of the wire rod, wherein the linear distance between the blower and the surface of the high-resistance anti-corona layer of the wire rod is 0.8 meter, detecting the surface temperature of the high-resistance anti-corona layer by using an online thermal infrared imager or an off-line thermal infrared imager (FLUKE Ti10 is used in the embodiment) conforming to the DL/T664 standard, wherein the linear distance between the thermal infrared imager and the surface of the high-resistance anti-corona layer of the test wire rod is 0.8 meter, and the surface temperature of the high-resistance anti-corona layer is not more than 90 DEG CWhen the surface temperature reaches 90 ℃, immediately removing the high voltage and suspending the test, loading the high voltage after the surface temperature of the high-resistance anti-corona layer is reduced to room temperature, continuing the test, repeating the test according to the rule until the test bar sample breaks down, counting the period when the external voltage reaches the specified value as the effective time, counting the total effective time until breaking down as the electrical aging time, calculating the average value of the breakdown life (voltage) of 4 test bars, and counting as L 1.6 ；
The sample selection principle, electrode treatment mode and wiring mode of sine wave and 190Hz electric aging test are the same as those of the test method under 50Hz power frequency, except that the stator test bar is required to be immersed into an oil groove for containing 25# transformer oil as a whole for test, the electric aging test is carried out under the condition of 1.4 times rated line voltage (21 kV), the test is carried out under the condition of continuously and continuously applying high voltage until the test bar sample breaks down, the time from the time when the externally applied voltage reaches a specified value is counted from the beginning, the time until the breakdown is counted as the electric aging time, the average value of the breakdown life (voltage) of 4 test bars is calculated, and the average value is recorded as L 1.4 ；
By the frequency-lifetime transformation formula: l (L) 1 ×f 1 ＝L 2 ×f 2 Will f 1 Lifetime at frequency L 1 Calculated as f 2 Lifetime at frequency L 2 The method comprises the steps of carrying out a first treatment on the surface of the Using formula L 2.17-50 ×50(Hz)＝L 2.17-190 ×190(Hz)、L 2.0-100 ×100(Hz)＝L 2.0-190 ×190(Hz)、L 1.6-150 ×150(Hz)＝L 1.6-intermediate frequency The x mid-level frequency (Hz) calculates the breakdown life L corresponding to 2.17 times rated line voltage, 2 times rated line voltage and 1.6 times rated line voltage under the mid-level frequency respectively 2.17-190 、L 2.0-190 、L 1.6-190 The method comprises the steps of carrying out a first treatment on the surface of the Using the formula Calculation E 2.17 、E 2.0 、E 1.6 And E is 1.4 Will [ (L) 2.17-190 、E 2.17 )、(L 1.4-190 、E 1.4 )]，[(L 2.0-190 、E 2.0 )、(L 1.4-190 、E 1.4 )]，[(L 1.6-190 、E 1.6 )、(L 1.4-190 、E 1.4 )]The data are respectively brought into the formula l=c×e -n To calculate the coefficient C corresponding to each group of data 1 、n 1 、C 2 、n 2 、C 3 、n 3 Using the formulaAnd->Determining breakdown life L extrapolated to rated line voltage 1 、L 2 And L 3 The average of these 3 data is determined +.>As the reference value of the service life design parameter of the insulating structure sine wave and the middle-level frequency-to-ground insulating structure of the multi-rubber molded stator bar of the hydraulic generator.
Claims (10)
1. A hydro-generator multi-rubber molded stator bar insulation sine wave to ground and medium frequency electric aging test method is characterized by comprising the following steps:
1. solving the breakdown life of the sine wave and the power frequency of 50Hz under the voltage of 2.17 times of rated line voltage of the multi-rubber molded stator bar, and recording as L 2.17-50 ；
2. Solving the breakdown life of the sine wave and 100Hz power frequency of the multi-rubber molded stator bar under 2.0 times of rated line voltage, and recording as L 2.0-100 ；
3. The breakdown life of the sine wave and 150Hz power frequency of the multi-rubber molded stator bar under the rated line voltage of 1.6 times is calculated and recorded as L 1.6-150 ；
4. Solving for multiple gluesThe breakdown life of the sine wave and the intermediate frequency of the molded stator bar under the rated line voltage of 1.4 times is recorded as L 1.4-intermediate frequency ；
5. Using formula L 2.17-50 ×50(Hz)＝L 2.17-intermediate frequency X mid-level frequency (Hz), L 2.0-100 ×100(Hz)＝L 2.0-intermediate frequency X mid-level frequency (Hz), L 1.6-150 ×150(Hz)＝L 1.6-intermediate frequency The x mid-level frequency (Hz) calculates the breakdown life L corresponding to 2.17 times rated line voltage, 2 times rated line voltage and 1.6 times rated line voltage at the mid-level frequency respectively 2.17-intermediate frequency 、L 2.0-intermediate frequency 、L 1.6-intermediate frequency ；
6. Using the formula Calculation E 2.17 、E 2.0 、E 1.6 And E is 1.4 The method comprises the steps of carrying out a first treatment on the surface of the E is the field intensity;
7. will [ (L) 2.17-intermediate frequency 、E 2.17 )、(L 1.4-intermediate frequency 、E 1.4 )],[(L 2.0-intermediate frequency 、E 2.0 )、(L 1.4-intermediate frequency 、E 1.4 )],[(L 1.6-intermediate frequency 、E 1.6 )、(L 1.4-intermediate frequency 、E 1.4 )]Three sets of data are respectively brought into the formula l=c×e -n To calculate the coefficient C corresponding to each group of data 1 、n 1 、C 2 、n 2 、C 3 、n 3 ；
8. Using the formulaAnd->Determining breakdown life L extrapolated to rated line voltage 1 、L 2 And L 3 The average of these 3 data is determined +.>The multi-rubber molded stator bar insulation structure is used as the breakdown life of sinusoidal waves and intermediate frequency of the hydro-generator.
2. The method for testing the electrical aging of the multi-glue molded stator bar of the hydraulic generator against the ground insulation sine wave and the medium frequency is characterized in that the multi-glue molded stator bar is a stator test bar which is manufactured by adopting a multi-glue molded insulation pressing process and only comprises a straight line part, a wire of the manufactured stator test bar is a copper conductor/an aluminum conductor, an insulation mica tape and a low-resistance/high-resistance corona prevention tape are covered outside, and the stator test bar is molded by compression molding and solidification.
3. The method for testing the electrical aging of the multi-gel molded stator bar of the hydro-generator against the ground insulation sine wave and the intermediate frequency according to claim 1 is characterized by comprising the following steps of 2.17-50 The method for solving the (3): carrying out sine wave and 50Hz power frequency electric aging test under the conditions of 2.17 times rated line voltage, air medium and continuous and uninterrupted high voltage application until the multi-glue mould pressing stator bar breaks down to obtain breakdown life, which is recorded as L 2.17-50 。
4. The method for testing the electrical aging of the multi-gel molded stator bar of the hydro-generator against the ground insulation sine wave and the intermediate frequency according to claim 1 is characterized by comprising the following steps of 2.0-100 The method for solving the (3): sine wave and 100Hz electric aging tests are carried out under the conditions of 2 times rated line voltage and air medium, 8 hours of electric aging tests are carried out every time, the test is stopped for 8 hours, and the test is repeated according to the rule until the multi-glue molded stator bar breaks down, so that the breakdown life is obtained and is recorded as L 2.0-100 。
5. The method for testing the electrical aging of the multi-gel molded stator bar of the hydro-generator against the ground insulation sine wave and the intermediate frequency according to claim 1 is characterized by comprising the following steps of 1.6-150 The method for solving the (3): sine wave 150Hz electric aging is carried out under the condition of 1.6 times rated line voltage and air mediumThe chemical test is carried out, a blower with the wind speed of 3.5 m/s is used for blowing the surface of the high-resistance anti-corona area of the wire rod, an infrared thermal imager or an ultraviolet imager is used for observing the surface temperature of the high-resistance anti-corona area, the continuous test is carried out under the condition that the hottest spot temperature of the surface of the high-resistance anti-corona area is not more than 90 ℃ until the multi-glue molded stator wire rod breaks down, the breakdown life is obtained, and the L is recorded as L 1.6-150 。
6. The method for testing the electrical aging of the multi-gel molded stator bar of the hydro-generator against the ground insulation sine wave and the intermediate frequency according to claim 5, wherein the linear distance between the blower and the surface of the high-resistance anti-corona area is less than 1 meter.
7. The method for testing the electrical aging of the stator bar of the hydro-generator by multi-gel molding on the surface of the insulation sine wave to the ground and the medium frequency is characterized in that the linear distance between an infrared thermal imager or an ultraviolet imager and the surface of the high-resistance anti-corona area is less than 1 meter.
8. The method for testing the electrical aging of the stator bar of the hydro-generator with the multi-gel molded to the ground insulation sine wave and the medium frequency according to claim 5, which is characterized by L 1.6-150 In the solving process, when the surface temperature of the high-resistance anti-corona area reaches 90 ℃, the test is stopped immediately, the test is continued after the temperature is reduced to the room temperature, and the test is repeated according to the rule until the multi-rubber mold-pressed stator bar breaks down.
9. The method for testing the electrical aging of the multi-gel molded stator bar of the hydro-generator against the ground insulation sine wave and the intermediate frequency according to claim 1 is characterized by comprising the following steps of 1.4-intermediate frequency The method for solving the (3): immersing the multi-rubber molded stator bar into transformer oil for sine wave and intermediate frequency electric aging test, wherein the test voltage is 1.4 times of rated line voltage, and testing under the condition of continuous uninterrupted operation until the multi-rubber molded stator bar breaks down to obtain the breakdown life, which is recorded as L 1.4-intermediate frequency 。
10. The method for testing the electrical aging of the multi-gel molded stator bar of the hydro-generator against the ground insulation sine wave and the intermediate frequency according to claim 1 is characterized in that the intermediate frequency is 180 Hz-200 Hz.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311080984.4A CN117192361A (en) | 2023-08-25 | 2023-08-25 | Multi-rubber molded stator bar insulation sine wave to ground and medium-frequency electric aging test method for hydraulic generator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311080984.4A CN117192361A (en) | 2023-08-25 | 2023-08-25 | Multi-rubber molded stator bar insulation sine wave to ground and medium-frequency electric aging test method for hydraulic generator |
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| CN117192361A true CN117192361A (en) | 2023-12-08 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311080984.4A Pending CN117192361A (en) | 2023-08-25 | 2023-08-25 | Multi-rubber molded stator bar insulation sine wave to ground and medium-frequency electric aging test method for hydraulic generator |
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| Country | Link |
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| CN (1) | CN117192361A (en) |
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- 2023-08-25 CN CN202311080984.4A patent/CN117192361A/en active Pending
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