SU1385186A1 - Electric machine stator - Google Patents

Abstract

The invention relates to electrical engineering. The purpose of the invention is to increase reliability. The stator of the electric machine contains a core, nuts mounted on the clamping wedges x 2, and electrical capacitance sensors of the pressing pressure. Due to the fact that the sensor is made in the form of a ring 6 with flanges on which electrically conductive plates are located on the formation of electrical capacitances, and one of the flanges is adjacent to the pressure flange 4 and the other to the nut 5, the accuracy and reliability of control of the pressing condition is increased. 1 hp f-ly. 3 il. with

Description

The invention relates to electrical engineering, in particular to electrical machines.

The purpose of the invention is to increase reliability by increasing the accuracy and reliability of monitoring the state of pressing.

FIG. 1 shows the stator of the electric, machine, general view; in fig. 2- pressure sensor, general view (node I in FIG. 1); in fig. 3 is a block diagram of a device including an electric capacitive pressure sensor and a secondary transducer for measuring the pressure of the pressing of the stator core of an electric machine.

The stator of an electric machine contains iron segments 1, mounted on clamping wedges x 2 and fixed at the ends by pressing fingers 3, pressing flanges 4 and nut 5.

Between the nut and the pressure flanges, an electrical capacitance pressure sensor of the pressing is installed, made in the form of a ring 6, the end parts of which are made in the form of flanges 7 and 8, ensuring a plane-parallel fit on the adana flange. On the flange 8 of the silopower element, an electrically conductive plate 9 is installed, for example, 9 of foiled polystyrene, a non-conductive substrate to isolates the plate 9 from the structural parts. On the flange 7 of the silopower element is fixed, for example; by means of screws, a ring 11, to which conductive plates 12-14, made of foil-coated textolite, are attached, non-conductive substrates isolate said plates from each other and from structural parts.

Plates 12 and 13 are separated by a rigid gasket 18, for example, metal rings of a constant cross section, through which a uniform gas gap is formed between the conductive plates 12 and 13. The conductive plates 12 and 13 and the closed gap between them form an electrical capacitance.

The conductive plates 9 and 14 are further separated by a uniform gas gap and form an electrical capacitance.

A casing 19 is installed on the flange 7 of the silo-deflecting element;

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The bolt 20 is attached in such a way that it excludes the possibility of tangential movement of the sensor and mechanical force contact with the stator pressure flange 4, the force-guiding element flange 8 and the nut 5.

The sensor connecting wires connected to the measuring transducer (PI) 21.

FIG. Figure 3 shows a block diagram of a device for measuring the pressure of the pressing of the stator core of an electric machine.

The device includes a capacitance-type pressure sensor 22, the signal from which is fed to the secondary PI 21. The PI consists of an information processing device 23 (AIS), a matching device 24, which receives a signal from AIS 23 and generates a signal proportional to the pressure of the press stator core on the display device.

The capacitance of the capacitor plates of a flat capacitor is determined by the formula

,

where is the absolute dielectric constant of the vacuum;

- relative dielectric permeability of the medium; S, d is the area of the capacitor plates and the distance between them.

When the pressure of the pressing is changed, a part of the power-generating element is deformed, as a result of which the distance between the electrically conductive plates 9 and 14 and, consequently, the magnitude of their electrical capacity Cp.

The electrical capacity Ce between plates 12 and 13 remains constant. Cp signals (the magnitude of which depends on the magnitude of the pressure of the compact and on the influence of side factors, such as, for example, size variation of electrically conductive plates due to heating by eddy currents, induced by stray fields, and conical heating from structural parts of an electric machine, and also dielectric constant gas gap due to the ingestion of oil vapors) and C, (the value of which depends only on the influence of side factors) is transferred to the secondary measuring transducer in which they are converted to

With

Since the electrical capacitances formed by the conductive plates 9, 14, 12, and 13 are in the same physical conditions, the value of the parameter K is independent with respect to the influence of side factors.

 the calibration dependence is P f (K) where P is the pressure perceived by the sensor in terms of K and determines the pressing pressure in the stator core of the electric machine.

The integrity of the design of the power-transmitting element of the sensor, which is in the power flow, ensures the elimination of measurement errors associated with the Coulomb friction arising in the places of violation of the integrity of the force-transmitting element. The elimination of the sensor movement in the tangential direction ensures that it is impossible to break the wires connecting the sensor to the secondary transducer during installation and operation. The placement of conductive plates in the inner cavity of the housing eliminates the possibility of mechanical damage.

Thus, finding the magnitude of the pressing force by the value determined by the ratio of the electric capacitances GO and Cp mounted on the one-piece power transmitting element of the pressure sensor protected from mechanical damage.

nor, install under each nut of the rigid wedge.

The electrical capacitances € and Ср are fed to the secondary transducer where they are converted

P in relation to K -. K value

and the dependences P f (K) incorporated in the matching device determine the amount of pressure of the pressing under each nut.

Based on the information received, a diagnosis is made about the state of pressing of the stator core of the electric machine.

Claims (1)

1. The stator of an electric machine, containing a core of iron segments, clamping wedges, pressure bolts and flanges, nuts mounted on clamping wedges and an electrical capacitance pressure sensor located between the nut and the pressure flanges, characterized in that, in order to increase reliability by increasing the accuracy and reliability of monitoring the state of the compact and the core, the sensor is made in the form of a ring of rectangular cross section with the supporting planes a casing installed in parallel to Q to fit the pressure flange with the exception of the possibility of tangential displacement of the last and mechanical contact of the casing with parts of the nut by flanges, on one of which, adjacent to the pressure flange, an insulated electrically conductive plate is installed, and on the flange torus located in the power flow, g sensor adjacent to the nut, set by the power-transmitting element, increases the reliability of the electric machine by increasing the accuracy and reliability of control of the state of pressing of the stator core. Monitoring of the state of pressing in operation is carried out as follows. 50 A ring is attached to which three insulated electrically conductive plates are attached, two of which are separated by a rigid gasket and a uniform gas gap to form an electrical capacitance, and a third is arranged to form a second electrical capacitance with a plate mounted on the flange of the sensor; to the pressure flange. equipped with calibration dependencies - - - - mi P f (K;), where P is the pressing pressure; TO; - the ratio of the electric capacitances i-rd of the pressure sensor 2. A stator according to claim 1, characterized in that a casing is attached to the flange of the sensor, uw || Under the nut, flanges, on one of which, adjacent to the pressure flange, is installed an insulated electrically conductive plate, and on the flange A ring is attached to which three insulated electrically conductive plates are attached, two of which are separated by a rigid gasket and a uniform gas gap to form an electrical capacitance, and a third is arranged to form a second electrical capacitance with a plate, the mouth is - - 2. A stator according to claim 1, characterized in that a flange is attached to the sensor flange, uw || 22 d f4 fmg.2