RU2456626C1 - Method for accurate detection of faults between first species equalisers of simplex lap winding of commutator machine armature - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: test voltage is supplied from a HV impulse generator onto two commutator plates whereto the ends of two adjacent equalisers are connected. One measures the pulsed magnetic field of axial direction short-circuit current of one of the said commutator plates with a pulsed magnetic field measuring indicator with an inductive sensor of astatic design having a slot air gap in its magnetic conductor oriented first along the axial direction of shirt-circuit current in the commutator plate. The indicator maximum reading is obtained by way of moving the sensor along the said commutator plates and adjustment of the test voltage and the indicator sensitivity values. The indicator sensor is displaced to the commutator necks and turned by 90 degrees. One measures the pulsed magnetic field of radial direction short-circuit current. One moves the sensor at the commutator necks height in the radial direction from the commutator operating surface and accurately detects a fault between the equalisers by sharp decrease of the indicator reading after the sensor passing the equalisers ends in the commutator necks.

EFFECT: accurate detection of faults between armature winding equalisers, extension of application field to include any types of armature lap windings with equalising connections and mixed windings with first and second species equalisers with any virtually possible transition resistances at the defect spot.

4 dwg

Description

The invention relates to the field of testing the windings of the anchors of collector DC electric machines with equalizing connections.

Known and widely used in practice is a method for detecting a short circuit between equalizers (see the book: Bessudnov EP, Detection of Insulation Defects in Windings of Electric DC Machines. Moscow, Energia, 1977. p. 78-90).

However, the known destructive method, requiring partial breaking of the armature winding circuit of several sections directly connected by equalizers with a short circuit between them, is forcedly applied in practice due to the absence of a non-destructive objective absolute concrete method for accurately detecting a short circuit between equalizers, especially at such stages of the technological process as after pulsed arc welding in inert gases of the armature windings with a collector and, especially, after vacuum-discharge p feeding anchors in an autoclave in an epoxy compound using Monolith type insulation. Such forced repair of a defective anchor leads to significant losses, does not contribute to the analysis of the causes of insulation defects and the improvement of the technological process of electric machine production and repair.

It is absolutely absolutely objective to precisely detect the short circuit between the equalizers of the first kind of a simple loop winding of the armature of the collector electric machine according to the principle underlying the Method for accurately detecting the location of the coil fault in the windings of the armature of collector electric machines with equalizing connections, RF Patent for the invention No. 2308730, IPC G01R 31 / 06 is also impossible because the invention is not intended for this purpose, since the technical result achieved by the invention is accurate and unambiguous the detection of a specific place (Point) of a short circuit around the perimeter of the defective section, without comparison, was possible due to the fact that the point of a short circuit (for example, the point of a short circuit of an OT in the collector coils) entering a short-circuited circuit with a short-circuit current shunts ( shorts) a faulty short-circuited turn, all equalizing connections and the rest of the undamaged part of the armature winding (see Application: 2005137904/28, 05.12.2005. Application publication date: 06/10/2007 Bull. No. 16. A method for accurately detecting the location of a turn fault in the windings of the armature of collector electrical machines with equalizing connections). If, in fact, there is a short circuit between the equalizers (which is essentially the same as the turn-in point in the collector hens, for example, with the total number of equalizers in the groove) and apply invention No. 2308730 to detect the alleged turn-in point, then we get the wrong (false) result: - the point of turn closure is in the headers of the collector, but in fact the point of closure between the equalizers is far from the collector and under two layers of the main simple loop winding of the armature, and to eliminate such a defect tion requires unwinding (rise) of the entire armature windings is not negligible and repair in case of short circuit Petushki collector. Therefore, before proceeding to the detection of a short circuit point in the windings of the armature with equalizing connections, you must first find out in which winding there is a short circuit: if - in the equalizing winding, then patented invention No. 2308730 cannot be applied, and vice versa.

Short circuits between equalizers take place both in the early technological stages and after welding the collector cocks and, as the long-term practice of applying insulation of the Monolith type has shown, after vacuum-injection impregnation in an autoclave in an epoxy compound and subsequent drying and heat treatment of the insulation of the armature windings. For example, after welding, before impregnation, permanent bandages are applied to the armature winding with adjustable tension of the glass band tape and registration of the number of stacked turns and the so-called technological box - a capsule, which prevents the compound from flowing out of the armature after impregnation until the end of polymerization. Therefore, an objective absolute concrete exact detection of a short circuit between equalizers is necessary, first of all, in order to make the only correct decision on how to deal with a defective anchor: whether to cut the spot welding on a lathe to a depth of about 2 mm and thereby save (save) the main simple loop winding and the main undamaged part of the equalizing winding, replacing one damaged section of the equalizing winding, if a short circuit between the equalizers is detected after welding of the collector cocks; whether to cut and remove both windings - the main simple loop and equalization, preserving the unwound anchor: collector and core - if an insulation defect is detected in the equalization winding after impregnation in an autoclave. It is for identifying and accurately detecting a short circuit between equalizers, as for the most severe case of an insulation defect, which requires completely unwinding the entire armature winding at any stage of the technological process to eliminate it, and the present invention is intended.

The objective of the invention is to reduce the time and labor to repair a defective anchor, increase labor productivity, reduce losses from irreparable defects, improve the quality and reliability of electrical machines, reduce factory costs for the manufacture of anchors, especially winding and collector copper, expensive insulating and impregnating materials, saving electricity spent on the entire technological process of electric machine production, providing the possibility of analyzing the causes of efekta isolation and improve the process of production and repair of electrical machine, including process equipment: automatic arc pulse welding in inert gases, bandazhirovochny machine, impregnation compartment with autoclaves, the machine-Machine prodorazhivaniya mezhlamelnoy micanite collector isolation.

The technical result achieved by the invention is an objective absolute concrete exact detection of a short circuit between the equalizers of the first kind of a simple loop winding of the armature in a non-destructive way at all stages of the technological process of electric machine production and repair and the expansion of the scope.

The test voltage is supplied from the pulse voltage generator to two collector plates to which the ends of two adjacent equalizers connected to the short-circuited circuit with a point of closure between the equalizers and the short circuit current are connected, and the ends of one of the sections directly connected by these equalizers measure pulse magnetic the short-circuit current field of the axial direction of one of these collector plates with an indicator - a pulsed magnetic field meter with an induction sensor of an astatic design with an air gap in its magnetic circuit — a slit oriented first along the axial direction of the short circuit current in the collector plate, achieve maximum indicator readings by moving the sensor across these collector plates, adjusting the test voltage and indicator sensitivity, then rearrange the indicator sensor to the cockerels collector, measure the pulsed magnetic field of the short circuit current of the radial direction, move the sensor p about the height of the collector cocks in the radial direction from the working surface of the collector and accurately detect a short circuit between the equalizers after passing the sensor of the pulsed magnetic field of the collector section with a radial direction of the short circuit current and changing its direction in the splines of the collector plates to inaccessible - axial - sharp reducing indicator readings after passing the equalizer ends sensor in the collector hens.

Figure 1 is a schematic diagram illustrating the principle of accurate detection of short circuits between equalizers of the first kind of a simple loop winding of an armature of a collector electric machine (using an example of an anchor of the NB-520 type in figure 3), based on the proposed method, based on detecting the location of a change in the direction of the short circuit current in a short-circuited circuit with a point of closure between the equalizers of the MUZ from the radial direction to the axial (relative to the axis of the armature shaft), that is, ninety degrees, after the transition of the induction sensor ID of zone I, indicated by a solid rectangle covering the ends 1 and 3 of the lower layer and the ends 2 and 4 of the upper layer of the equalizing winding part with an insulation defect, into zone II, indicated by a dashed rectangle covering the conclusions of turns 5 of the upper and lower layers of the corresponding part of the main loop winding anchors; figure 2 illustrates the practical implementation of the proposed method: the initial initial location of the induction ID sensor in an epoxy housing on an insulating measuring rod above the working surface of the collector and relative to the current-carrying contacts (spring-loaded inside its housing) on the insulating panel connected to the high-voltage output of the GIN and Earth ( see figure 1, contacts 10 and 9, respectively) at a particular test object - the anchor of a six-pole traction electric motor of the NB-514B type of the main cargo electric AC electric locomotives of the 2ES5K series (two sections) and ZES5K (three sections) - at the initial technological stage of the manufacture of the armature with protruding uninsulated ends of equalizers 1, 2, 3, 4 and terminals of the turns of the loop winding 5 from the slots of 6 cockerels of the collector plates. The photograph of the armature collector section in FIG. 2 also illustrates the collector plate as a busbar with one supply connection (pin 10 or 9 in FIG. 1) and four outgoing connections (equalizers 1 and 2 or 3 and 4; and two turns 5 of the loop winding, lying in one slot 6 of the same collector plate): the designations in Fig. 2 are indicated on similar collector plates, but are shifted in comparison with the same designations in Fig. 1, since the induction ID sensor covers the ends of the equalizers necessary for designation in the photograph; figure 3 illustrates the practical implementation of the proposed method on another specific test object - the anchor of a six-pole traction motor of the type NB-520 main passenger electric locomotive series EP1, EP1M, EP1P, the laying sequence of equalizers 1, 2 and 3, 4 of which is shown in figure 1: sequence alternation of collector plates 7 with equalizing slots (with equalizers 1, 2 and 3, 4) and - without equalizers - at the stage - after pulse arc welding of the armature windings with the collector before machining the weld points ki (dark ring in the upper part of the collector) - with an insulating tripod mounted on the shaft of the tested armature (see the general view of the insulating tripod assembly in isometric view in the photograph of Fig. 4), the height of which is moved and fixed to the bracket with two current-carrying spring-loaded inside its case contacts (High 10 connected to the GIN Output, and Earth 9, see Fig. 1) on the insulating panel, and the second bracket in the form of an insulating measuring rod with an induction ID sensor, which is exposed and fixed above the coil leads of the cockerels the collector of that section of the loop winding, to the adjacent equalizers of which they supply a test voltage from the GIN; in Fig. 4, separately from the test object (anchor), an insulating tripod (made of 40 mm thick sheet PCB assembled in isometry) is shown with its movable height (through a pipe fixed in a special guide, bolted to the top of the insulating tripod) and rotated around the pipe axis and two brackets fixed on the tripod pipe: one with two spring-loaded high-current and earth-contacting contacts (with two parts of the body being disassembled on the thread) and connected to the high and earth GIN Output and the second crown Thane - induction sensor ID to the end of the measuring rod with an insulating clamp position sensor (height and around its axis). The lower part of the insulating tripod is fixed (contracted) on the shaft of the tested anchor with a clamp (visible on the right) and connected to the upper part of the tripod using a loop (visible on the left). A tight fit of the insulating tripod to the shaft of the tested armature ensures reliable contact between the spring contacts High and Earth with the armature collector plates, which is especially important when the short-circuit current flows to the fault point between the equalizers - the MUS point and with very small dimensions of the working surface of the collector plate 7 thick, about 3 mm and with the thickness of the micanite spacers 8, about 1 mm (see figure 1, figure 2, figure 3). In addition, this design of an insulating measuring tripod allows one person to test insulation of armature windings, for example, an OTK employee.

Since the short circuit between the equalizers of the first kind (MUZ point 1), lying under the frontal part of the two-layer simple loop winding of the armature from the collector side, is nothing more than a short circuit between the corresponding collector plates to which they are connected according to the scheme, therefore that the equalizers of the first kind are non-inductive, leading to a short circuit of the corresponding turns of the main simple loop winding of the armature, then first clearly and concretely detect three sections of the armature winding for I have six-pole traction motors located at an angle of one hundred and twenty degrees relative to each other around the circumference of the armature, for example, NB-520 (Fig. 1 and Fig. 3), NB-514 (Fig. 2) (DTC - 800 A - a six-pole traction motor main freight DC electric locomotive 2ES4K, NTK-650 series - a six-pole traction electric motor of an industrial electric locomotive NP1 series), directly interconnected by equalizers, between which there is a short circuit between the equalizers - MUZ point (Fig. 1), as in the case of a round circuit VZ: - according to the demagnetizing effect of short-circuited turns - according to the law of E. Lenz - the law of reversibility of electromagnetic induction - and by methods of copyright certificates: No. 205941 IPC H02D G01R and No. 297008 IPC G01R 31/06: when applying a surge voltage to the collector relative to the armature - during shock pulse excitation of the armature windings as a complex oscillatory system, due to the discharge of the generator of pulse voltage generator GIN, the source of the test pulse voltage. The indicated three sections are characterized by the same levels of the pulsed magnetic field when the induction sensor ID of the pulsed magnetic field meter IIP is located above any part of the armature: above the slots of the armature core, above the frontal part of the armature winding or above the coil leads at the collector cocks. Precisely unambiguously and specifically, these three sections are detected by the minimum (almost zero) readings of the IIP indicator when the ID sensor is located above two groove teeth with the upper side of each of these three sections (see book: E. Bessudnoye. Detection of places of insulation defects in electric windings DC machines. M., Energy, 1977, S. 22-48, 67-80).

Further, at the ends of two adjacent equalizers 1, 2 and 3, 4 included in the short-circuited circuit, presumably with a point of closure between the equalizers of the MUS and the short-circuit current I _SC , and at the corresponding ends of the turns 5 of one of three detected by the demagnetizing effect of the short-circuited turns , sections of the loop winding lying in the corresponding slots 6 of the collector plates 7, using the contacts 9 and 10 connected to the output of the GIN 11, test voltage is supplied from the GIN with a pulse repetition rate of, for example, 50 imp / s collector plates 7 with the ends of equalizers 1, 2 and 3, 4 (see FIGS. 1, 2, 3): according to the layout of the equalizing winding of a particular type of armature in equalizing slots 6 of the corresponding collector plates (see, for example, FIG. 1 for anchors type NB-520).

The pulsed magnetic field of the short-circuit current of the axial direction of one of these collector plates is measured by an indicator - a pulsed magnetic field meter ИИП 12 with an astatic-type induction ID sensor having an air gap in its magnetic circuit — a gap oriented along the axial direction of the short-circuit current I _КЗ in one of of these two collector plates, achieve the maximum readings of the IIP indicator 12 by moving the ID sensor across these collector plates, adjusting the value test voltage GIN 11 and the sensitivity of the indicator IIP 12 (figure 1 and figure 2). Next, the ID sensor is rearranged (Fig. 2) to the headers of the armature collector in zone I (Fig. 1) and the pulsed magnetic field of the short circuit current of the radial direction is measured. And, finally, the ID sensor is moved along the height of the collector cocks in the radial direction from the working surface of the collector from zone I to zone II (Fig. 1) and the circuit between the equalizers is accurately detected after passing through the sensor of the pulse section of the collector cocks with radial direction that is available for measuring the pulsed magnetic field short-circuit current and changing its direction in the slots of the collector plates to inaccessible - axial - by a sharp decrease in the readings of the IIP 12 indicator after passing the ID sensor of the equalizer ends d in collector cocks: after the ID sensor transitions from zone I, indicated by a solid rectangle in Fig. 1, to zone II, into a dashed rectangle that covers the ends of the turns of the main simple loop winding of the armature, shunted (shorted) by a short-circuited circuit with a point of closure between the equalizers - A MUS point with a short circuit current I _KZ flowing in the axial direction according to equalizers under a two-layer simple loop winding of the armature: along an invisible threshold (step) (see figure 3 - anchor NB-520 - at the manufacturing stage after welding the collector cocks before impregnation in an autoclave and cf. figure 2 - the anchor NB-514 - after laying the winding - the initial technological stage) in the only accessible place of the armature (the outer visible side of the collector cocks) for measuring the pulsed magnetic field at the same sensitivity of the IIP indicator with an ID sensor as to a pulsed magnetic field equalizing winding, and to the field of the main simple loop winding. In this case, the collector plate should be considered as a busbar with one supply connection from the GIN (current-carrying contacts connected to the GIN Output - High 10 or Earth 9 in Fig. 1 and Fig. 2) and four outgoing connections in the slots of the collector cocks: lower and upper layer equalizing winding 1, 2 and 3, 4 and the lower and upper layer of a simple loop winding 5 of the armature (figure 1 and figure 2). Accurate detection of a short circuit between equalizers in a non-destructive way was possible due to the high selectivity of pulses with a steep edge equal to a fraction of a microsecond, a pulsed test voltage of a GIN on a practically non-inductive load of a GIN - a short-circuited circuit with a short circuit point between adjacent equalizers, in comparison with a selective ability, for example, DC voltage usually used by the method of millivoltmeter - by the voltage drop on a short-circuited circuit, and due to the high sensitivity and selectivity of the Method underlying the measuring instrument of pulsed magnetic fields IIP 12 (Method for measuring pulsed magnetic fields. Copyright certificate for the invention No. 444139 M. Cl. G01r 33/00) with an induction ID sensor of an astatic design having in its magnetic circuit air gap - gap.

The main fundamental distinguishing features of the present invention, initially indicating that the collector plate should not be considered as a node (point, solid metal), but as a busbar with one connection from the GIN and four outgoing connections: two equalizers (lower and upper) and two turns (lower and upper) of the armature loop winding based on the measurement of the pulsed magnetic field of the short-circuit current I _SC in a short-circuited circuit with a point of closure between equalizers (MUZ point) for one and the same sensitivity of the IIP indicator with an induction ID sensor both to the pulsed magnetic field of the equalizing winding and to the field of the main simple loop winding, in the only accessible place of the armature (collector cock) along the invisible threshold (step) of changing the spatial direction of the flow of the short circuit current I _KZ ninety degrees - from radial to axial (relative to the axis of the armature shaft), - provide the ability to accurately detect the short circuit between the equalizers of the first kind (wave winding) and second kind of (loop coil) in four-mixed (frogs, consisting of the wave and the loop coils of different versions) windings of the armature commutator electric machines of direct high-power current. It is the four-layer design of the mixed (frog) armature windings and, therefore, the inaccessibility for measuring the pulsed magnetic field of the loop winding lying under the upper layer of the wave winding, complicates the practical application of the Method - RF Patent for invention No. 2308730 IPC G01R 31/06, and, in addition , in such windings two short-circuited circuits are formed with turns of the loop and wave windings during a short circuit in one of them: for more details see book: E.P. Bessudnov. Detection of insulation defects in windings of electric DC machines. M., Energy, 1977.S. 82-83.

Since all operations when detecting a short circuit between the equalizers of the MUS are performed manually under voltage from the GIN in the immediate vicinity of the collector using an insulating measuring rod with an induction ID sensor at its end (Fig. 2) and using an indicator - meter of pulsed magnetic fields IIP 12 ( 1), isolated from the Earth, with autonomous power supply from a 9 V DC voltage source, it is advisable to use a second induction ID sensor (Fig. 3 and Fig. 4), which is exposed above the leads of the turns at the cockerels of the armature collector, owls estno second indicator SMPS identical to the first measurement kit described above. The second measuring set of ID and IIP is necessary in order to judge by the minimum readings of the IIP indicator (almost zero) that there is no short circuit in the main loop winding of the armature when adjusting the test voltage from the GIN in a wide range from zero to an acceptable value for micanite insulation 8 between collector plates 7 (figure 1), for example, a short circuit or electrical breakdown through an insulation arc between the turns of the upper and lower layers of the loop winding, which are connected to the same collector plates as the adjacent equalizers considered with the assumed at the initial stage of the search for an insulation defect, without resorting to manual operations using the first measuring set of ID and IIP, and to accelerate the detection (recognition) of all possible options (combinations) of short circuits as in equalizing and in the main loop windings of the armature and, especially, in mixed (frog) windings with equalizers of the first and second kind.

Thus, the described invention provides the ability to absolutely objectively specifically accurately detect the short circuit between the equalizers of the armature windings in a non-destructive manner for any practically possible transient resistances in the place of the insulation defect (during metal short circuits and during electrical breakdown of insulation between the equalizers through the arc) and is applicable at all stages of the technological the process of electric machine production as for simple loop single-closed and complex loop multi-close Fifth, and for mixed (frog) the armature windings as any (simple and complex) performance.

Claims (1)

A method for accurately detecting a short circuit between equalizers of the first kind of a simple loop winding of the armature of a collector electric machine, characterized in that the test voltage is supplied from the pulse voltage generator to two collector plates to which the ends of two adjacent equalizers included in a short-circuit with a point of closure between the equalizers and short circuit current, and the ends of one of the sections directly connected to each other by these equalizers measure the pulsed magnetic field current short circuit of the axial direction of one of these collector plates with an indicator-meter of pulsed magnetic fields with an induction sensor of an astatic design having an air gap-gap in its magnetic circuit, oriented first along the axial direction of the short circuit current in the collector plate, reach the maximum indicator readings by moving the sensor across of these collector plates, adjusting the magnitude of the test voltage and the sensitivity of the indicator, then they put the indicator sensor to the collector headers, measure the pulsed magnetic field of the short-circuit current of the radial direction, move the sensor along the height of the collector headers in the radial direction from the collector surface and accurately detect the short circuit between equalizers after the sensor passes through the sensor pulsed magnetic field section of the collector headers with radial the direction of the short circuit current and a change in its direction in the slots of the collector plates to the inaccessible - axia noe - the sharp decrease in the gauge, after passing the sensor end equalizers Petushki collector.

Images