CN85104755A - The method and the device of test enameled wire and impregnating varnish compatibility - Google Patents

Abstract

A kind of method and device of testing enameled wire and impregnating varnish compatibility, test method is to the enameled wire sample behind the dipping lacquer, under the condition of heat aging, measure time spectrum and the TEMPERATURE SPECTROSCOPY of dielectric loss factor tg δ, the aging speed that reacts according to this spectrum decides its compatibility.The present invention also provides a kind of device that comprises the test compatibility of heating arrangement, thermopair, temperature controller, dielectric analysis instrument, X-Y recorder etc.Sample is simple during with this method, determines that compatibility is fast.Can prevent insulation and the incompatible system insulation decline that causes between the impregnating varnish even breakdown owing to enameled wire.

Description

The method and the device of test enameled wire and impregnating varnish compatibility

The present invention relates to a kind of method and device thereof that carries out enameled wire and impregnating varnish compatibility test by the dielectric loss measurement.Particularly with the relevant compatibility test method and apparatus of life-span of enameled wire after impregnating varnish is handled.

Along with F, the widespread use of H level macromolecule enameled wire in electrical equipment such as transformer and motor etc., obtain performances such as good heat conduction, machinery, protection against the tide for making insulation system, need this insulated part dipping lacquer.When enameled wire after impregnating varnish is handled, the compatibility between two kinds of insulating material is extremely important.If the result of physics, chemistry or physicochemical combined action between two kinds of insulating material of lacquer that is coated with on the enameled wire and impregnating varnish is inconsistent, will cause the insulation of total system to descend even breakdown.Thereby should at first carry out the compatibility test of enameled wire and impregnating varnish, so that select the appropriate insulation combination of materials.The method of compatibility test is a lot, and pencil hardness method is wherein arranged, 4 methods etc. of reporting to the leadship after accomplishing a task of bearing a heavy burden.But above-mentioned two kinds of method reliabilities are not high.Listing the breadboard relevant compatibility test standard of U.S. UL in has UL1446 insulating material system standard, sample is placed in the sealed tube wears out, and carries out flash test then.China will also have set up corresponding test standard JB/DQ3111-84 in the end of the year 83 on this basis, each group partition inter-capacitive qualification test method of electrical equipment industry office of promptly Chinese Ministry of Machine-Building Industry company standard electrical machine insulation structure.After the main rules of this method were dipping lacquer, enameled wire is enclosed sealed tube made it being higher than 25 ℃ of grade temperature down aging 336 hours (14 days), compares the breakdown voltage value of seal aging front and back then, judges its compatibility according to the decline degree of voltage breakdown.But the data dispersiveness of this breakdown potential platen press is very big, is destructive to the mensuration of sample, and judges that the time that compatibility needs is longer.In addition FDAC Tanaka five youths that make institute on October 24th, 75 disclosed spy open proposition insulated electro group determination method in the clear 50-134190 patent " fitness test of enameled wire and impregnating varnish ".This method is with two enameled wires close spirally-wound coil in the bar of garden, and carry out putting into developmental tube after the release processing, teflon garden rod is inserted at the center, harden, make enameled wire to make garden tubular test portion after injecting impregnating varnish, behind heat aging, measure its insulation resistance during moisture absorption, wherein aging moisture absorption hocket each circulation be five days promptly 180 ℃ of heating 2 days, moisture absorption is 3 days under 40 ℃, 95% specific humidity, drops to 10 according to insulation resistance ⁵Period during M Ω is judged its compatibility.Comparatively bother but do sample production like this, and except that heating, also need the bigger environment of humidity, and it is still longer to measure the needed time of result.

To the purpose of this invention is to provide a kind of sample production easy in order to overcome above shortcoming, measure to non-destructive continuously, and short method and apparatus of required test duration.

Method provided by the present invention is that a kind of method of testing the compatibility of enameled wire and impregnating varnish comprises the enameled wire sample after flooding with impregnating varnish, under the condition of heat aging, measure the dielectric spectra of its dielectric loss factor tg δ, decide its compatibility according to the aging speed that dielectric spectra reacted.

The present invention also provides a kind of device to its compatibility of specimen test behind the enameled wire dipping to comprise the heating arrangement that enameled wire can be housed, thermopair, temperature controller, the dielectric analysis instrument, X-Y recorder, the input end of dielectric analysis instrument is linked the enameled wire sample that is placed in the heating arrangement, and the tg δ value analog quantity that electrical measurement goes out is transported to the Y input end of X-Y recorder, the output of thermopair is delivered to temperature controller with the temperature in the indication heating arrangement, temperature controller is that the temperature in heating arrangement power supply and the control heating apparatus is predetermined constant temperature value, and output and the corresponding voltage of temperature are to the X input end of X-Y recorder.

It is as follows that accompanying drawing is explained the main points briefly:

Fig. 1, be the calcspar of compatibility test device;

Fig. 2, be the synoptic diagram of enameled wire single line sample;

Fig. 3 a, be the front view of enameled wire model coil;

Scheme b, be the top view of enameled wire model coil;

Fig. 4, be the time spectrum of each assembled scheme;

Fig. 5, the tg δ TEMPERATURE SPECTROSCOPY when not flooding under the different sealing digestion time for the QZY enameled wire

Fig. 6, be the QZY enameled wire with the tg δ TEMPERATURE SPECTROSCOPY under No. 11477 lacquer dipping back different sealing digestion times;

Fig. 7, for modification QZY enameled wire with the tg δ TEMPERATURE SPECTROSCOPY under No. 11477 lacquer dipping back different sealing digestion times;

Fig. 8, the temperature when being certain certain value and seal aging time relation figure for tg δ;

Fig. 9, be that voltage breakdown descends with the downtrending figure of seal aging time;

Figure 10, be air tubular heater formula compatibility measurement mechanism figure.

Below in conjunction with most preferred embodiment invention is elaborated.

The sample of enameled wire has twisted wire (seeing Fig. 1 and Figure 10), single line (see figure 2) and model coil styles such as (seeing Fig. 3 a and 3b), and wherein can to adopt the UL-1446 standard be the NO.18AWG(0.82mm of rope-lay conductor by two equal in length to twisted wire [4] ²) the even twisting of thick-layer electromagnetic wire forms for 8 times, twisting is long 4.75 inches (121mm) partly.The twisting tension is that 3 pounds of (13.3 newton) two ends respectively stay 2 inches (50.8mm) to refuse twisting.The single line sample then is being coated with the graphite suspension that is added with activating agent with a section behind the dipping lacquer on paint film [12], form graphite electrode [11], the length that scribbles graphite can be for example 30 millimeters, can use the clip support of being made by conductive material on the graphite electrode section, can connect lead on clip.The insullac and the impregnating varnish that form with enameled wire between graphite electrode [11] and the enameled wire lead [13] are the electric capacity of medium.The model coil sample is can be with in the two-layer embedding wire casing [32] about two groups of coils branches by the coil of enameled wire two-wire coiled [31], [33] then be the binding post of coil, between the two-wire of single group coil or the insullac and the impregnating varnish that all exist with enameled wire between two groups of coils be the electric capacity of medium, can test its compatibility near the situation of motor windings.

The dielectric spectra of measuring the hot dielectric loss factor tg δ of sample has two, one to be the time spectrum of tg δ, and one is the TEMPERATURE SPECTROSCOPY of tg δ.Can be used for separately judging that compatibility also can combine two kinds of spectrums judges.

Is that sample [4] is enclosed in the sealed tube [3] referring to Fig. 1 to the measuring method of tg δ time spectrum, and tight socket [16] then is fixed on the baking oven as the shelf in the baking oven [17] by being fixed on heating arrangement [1].Oven temperature is warming up to is higher than 25 ℃ of class of insulation temperature and for example keeps constant temperature after 180 ℃, two extension lines of sample are received the tester that dielectric loss is tg δ, surveyed tg δ value of record every 8-12 hour, the voltage corresponding to tg δ value that maybe will record is delivered to the Y input end of X-Y recorder, continuous recording tg δ-time curve, the i.e. time spectrum of tg δ.Referring to Fig. 4, Fig. 4 is the time spectrum of tg δ, wherein the QZY curve is the tg δ time spectrum that QZY enameled wire (polyester imines enameled wire) does not record during dipping lacquer, change the QZY+11477 curve and be modified polyester imines enameled wire with the tg δ time spectrum behind No. 11477 lacquer dippings, the QZY+11477 curve is the tg δ time spectrum after the polyester imines enameled wire floods with No. 11477 lacquers, as can be seen from the figure tg δ is minimum when dipping lacquer does not promptly have consistency problem, dielectric loss is more higher behind the modification QZY dipping lacquer, curve is more flat, is generally less than 0.3.But tg δ value just begins progressively to rise two days later behind the QZY dipping lacquer, second day tg δ is 0.25, the four day to be to be 0.99 in 0.63, the six day, later on the rate of growth of tg δ reduces, rises slowly, thus when testing compatibility with time spectrum six days with interior can find out whether compatible.Change QZY and 11477 compatible, thereby tg δ-directly is QZY and 11477 incompatible so dielectric losses big and increase very fast less than 0.3.Thereby in the time spectrum tg δ to increase fast be incompatible.

The measuring method of tg δ TEMPERATURE SPECTROSCOPY is carried out heat aging with said method in above-mentioned baking oven many (for example 7) samples being placed in the sealed tube, do the original test portion except that keeping one, all the other press certain hour at interval for example by 1,4,7,11,14, took out a sample in 17 days at interval respectively, this sample is put into the air tubular heater, (see figure 10) rises to 250 ℃～300 ℃ its linear temperature increase speed with temperature from room temperature and can be for example 20 ℃ of/minute relations of measuring its tg δ and temperature, because heat aging asynchronism(-nization), measured curve is also different, thereby the sets of curves that test obtains is TEMPERATURE SPECTROSCOPY.Fig. 5, Fig. 6, Fig. 7 are respectively not dipping lacquer of QZY enameled wire, and the QZY enameled wire is with No. 11477 lacquer dippings, and modification QZY enameled wire is with the TEMPERATURE SPECTROSCOPY under three kinds of situations of No. 11477 impregnating varnishes.Interval in the Fig. 5 that does not have consistency problem between each curve of TEMPERATURE SPECTROSCOPY is minimum, belongs to incompatible situation at interval very greatly among Fig. 6, and the symbolic animal of the birth year condition of showing mercy more still at interval among Fig. 7.Get o'clock the 4th day the curve in tg δ=0.3 and compare with first day curve as just changing QZY+11477, temperature descends 56 ℃ and get tg δ=0.3 equally with regard to QZY+11477, and descending reaches 108 ℃.And from figure, also can draw a kind of like this rule, under changing the compatible situation of QZY+11477, get tg δ=0.3 o'clock the 4th day and compared in three days descend 56 ℃ and the 11st day of temperature with first day and compared with the 4th day and only descend in seven days 36 ℃.Getting tg δ=0.3 the 4th under the inconsistent situation of QZY+11477 day compared descend 108 ℃ and the 11st day of temperature and compared with the 4th day and only descend about 40 ℃ with first day.Because later 7 days variation is less, thereby variation tendency can find out at the 4th day, so the test duration can shorten dramatically.Simultaneously as the curve (see figure 8) that TEMPERATURE SPECTROSCOPY is changed temperature and seal aging fate when getting tg δ and be certain value because this curve descends with index law basically, curve that calculates according to index law (being represented by dotted lines) and actual measured value (representing with solid line) differ very little as can be seen from Figure.Because it is fast that this curve begins to change, variation later on is slow, just can judge compatibility according to variation tendency in four, five days before the institute.Thereby in the TEMPERATURE SPECTROSCOPY curve descend curve decline rate big or Fig. 8 at interval fast be incompatible.

Fig. 9 for soak No. 11477 lacquers according to the UL-1446 standard with the measured QZY enameled wire of breakdown potential platen press and change-the QZY enameled wire soaks the voltage breakdown decline situation of coating with lacquer for No. 11477, can be used as relatively to reach reference.The voltage breakdown retention rate is 25～46% during QZY+11477, and actual type approval test result is breakdown, illustrates that two kinds of insulating material are incompatible.And the voltage breakdown retention rate is 80～104% when changing QZY+11477.The real machine type approval test is passed through, and illustrates that two kinds of insulating material are compatible.But required time of the method for this test compatibility is longer.

The visible Fig. 1 of the device of test compatibility provided by the present invention and Figure 10.This device comprises heating arrangement [1] as shown in Figure 1, thermopair [2], temperature controller [6], dielectric analysis instrument [7], X-Y recorder [8].Wherein heating arrangement [1] is an electric dry oven, is placed with the enameled wire sample in the electric dry oven, is housed in the sealed tube, and is fixed on together in the baking oven, can carry out seal aging to sample, and can be used for the time spectrum of follow-on test dielectric loss.Also have resistive heater [5] to be used for being baking oven for heating in the baking oven, its heating is supplied with through temperature controller [6] with supply voltage, thermopair [2] can be exported and the corresponding voltage of heating arrangement [1] internal temperature, deliver to temperature controller [6] with indication temperature wherein, the temperature of temperature controller [6] may command heating arrangement [1] remains on the predetermined temperature it, and temperature linearity is risen.Sample [4] has extension line to link to each other with dielectric analysis instrument [7] and measures the tg δ value of sample [4], by the Y input end of dielectric analysis instrument [7] output tg δ voltage to X-Y recorder [8], temperature controller [6] also export with heating arrangement [1] in the corresponding voltage of temperature deliver to the Y input end of X-Y recorder [8], X-Y recorder [8] can write down the various curves of tg δ.

Device among Figure 10 is identical with Fig. 1, principle of work is also identical, difference only is that heating arrangement [1] is the air tubular heater, heater coil coiled helical is tubular, skin has insulating layer for example to have three layers, core is that temperature error is only ± 1 ℃ within the 15mm of center line radius in even temperature field distribution basically in the stove, since the little rectilinearity quick heating of caliber can 20 ℃/minute speed heat up, be convenient to measure the dielectric loss TEMPERATURE SPECTROSCOPY that sample is path samples such as twisted wire or single line, but owing to can not under the sealing situation, sample be worn out or test so can not survey the time spectrum of dielectric loss.

Claims (9)

1, a kind of method of testing the compatibility of enameled wire and impregnating varnish, comprise under the condition of heat aging, measure the dielectric spectra of its dielectric loss factor tg δ with the enameled wire sample behind the impregnating varnish dipping, determine its compatibility according to the aging speed that dielectric spectra reacted.

2, the method for claim 1, wherein the dielectric spectra of the tg δ of Ce Lianging is the time spectrum of dielectric loss factor, the sample in the sealed tube is placed on is heated in the heating arrangement that to measure the time dependent curve of tg δ after temperature is higher than 25 ℃ of class of insulation temperature and keeps constant temperature be its time spectrum.

3, method as claimed in claim 1 or 2, wherein the dielectric spectra of the tg δ of Ce Lianging is the TEMPERATURE SPECTROSCOPY of dielectric loss factor, and will being higher than sample in the sealed tube of aging different time in the constant temperature of 25 ℃ of class of insulation temperature in temperature, to measure the temperature variant curve of tg δ respectively temperature progressively is elevated to 250～300 ℃ condition from room temperature under be its TEMPERATURE SPECTROSCOPY.

4, method as claimed in claim 3, wherein the temperature linearity ascending velocity is that per minute rises 20 ℃.

5, a kind of device to its compatibility of specimen test behind the enameled wire dipping comprises the heating arrangement [1] that the enameled wire sample can be housed, thermopair [2], temperature controller [6], dielectric analysis instrument [7], X-Y recorder [8], the input end of dielectric analysis instrument [7] is linked the enameled wire sample [4] that is placed in the heating arrangement [1], and the tg δ threshold voltage of measuring is transported to the Y input end of X-Y recorder [8], the output of thermopair [2] is delivered to temperature controller [6] with the temperature in the indication heating arrangement [1], temperature controller [6] is heating arrangement [1] power supply, and the temperature in control heating apparatus [1] is predetermined constant temperature value, and output and the corresponding voltage of temperature are to the X input end of X-Y recorder [8].

6, device as claimed in claim 5 wherein heating arrangement [1] be electric dry oven, can be used for sample is carried out seal aging and measures the time spectrum of its tg δ.

7, device as claimed in claim 5 wherein heating arrangement [1] can be used for measuring the TEMPERATURE SPECTROSCOPY of the tg δ of sample for the air tubular heater.

8, be twisted wire as wherein used sample as described in claim 1 or 5.

9, be single line as wherein used sample as described in claim 1 or 5.And on the enameled wire behind the dipping, be coated with the preceding paragraph and be added with the graphite suspension of activating agent as a conductive electrode.

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