SU1334271A1 - Electric machine stator - Google Patents

Abstract

The invention relates to electrical engineering. The purpose of the invention is to increase the reliability of the electric machine. The stator of the electric machine contains iron core segments, pressure pins, flanges and wedges. Between the nut 5 and the pressure flange 4 there is installed a capacitive pressure sensor for pressing the core, consisting of four conductive plates 9 and 14, between which there is an air gap. Plates 9 form a variable electrical capacitance, and plates 14 form a constant electrical capacitance with a calibrated gap. Each pair of plates is connected to the secondary transducer separately from each other. This makes it possible to eliminate the influence on the measurement result of factors that are not directly dependent on the pressing of the stator core. 3 il. S cl with 2 Г оо со ГЧЗ s

Description

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

The purpose of the invention is to increase the reliability of the electric machine by increasing the accuracy and reliability of diagnostics of the state of pressing of the stator core in operation.

FIG. 1 shows the stator of an electric machine, general view; S1 of FIG. 2 — pressure sensor, general view; Fig. 3 is a block diagram of a device including a capacitive type pressure sensor and a secondary transducer for measuring the pressure of the pressing of the stator core of the electric machine.

The stator of the 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.

Under the nut set steel washers 6, separated by a ring of 7. Burlievoy bronze. To the steel washers, washers 8 were attached from foil-laminated textolite. The foil layer 9 performs the role of conductive plates (plates) of the variable capacitance of the sensor. Conductive plates 9 are connected to the secondary transducer 10 by means of connecting wires 11

A steel cup 12 is installed under the washers 6, to which washers 13 are made of foil-coated textolite, the foil layer of which serves as conductive plates (plates) 14, which are connected to the secondary measuring transducer 10 by connecting wires 11. Washers 13 are separated by a ring 15 of burrilium bronze . The thickness of the ring 15 is such that it provides an air gap between the washers 13, equal in size to the air gap between the washers 8,

A capacitive-type sensor (EI) 16 outputs a signal to a secondary measuring transducer (PI). 10. The secondary measuring transducer consists of an information processing device (UOI) 17, receiving a signal 55 to the influence of side factors.

From the sensor of the coordinating device (SU) 18, which receives a signal from the OID and which outputs a signal proportional to the pressing pressure of the stator core to the display device (UI) 19 (FIG. 3).

The electrical intensity between the plates is determined by the formula

-R

 with ; S

- toi

0

five

0

0

where o S, d is the absolute dielectric constant of the vacuum; - relative dielectric permeability of the medium; area of capacitor plates and the distance between them. When the pressure of the compact is changed, the ring 7 is deformed, thereby changing the distance between the conductive plates 9, which leads to a change in their electrical capacity Cp.

The electric capacity CQ between the plates 14 remains constant, as the glass 13 protects them from mechanical forces caused by the pressure of the stator core pressing due to the presence of a gap between the steel washer 6 and the textolite washer 13, the value of which exceeds the maximum deformation 12, under the action of mechanical loads and temperature.

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 changes in the dimensions of the electrically conductive plates due to heating by eddy currents induced by scattering and conductive heating from the structural parts of the electric machine, as well as changes in the dielectric constant due to the ingress of oil vapors into it) and Co (the value of which depends only on the influence of side factors) are transferred to the secondary measuring transducer, -. rum these signals convert to

35

40

45

With

K -.

R

50 Since the electric capacitances formed by conductive plates 9 and 14 are in the same physical conditions, the value of the parameter K is independent with respect to the calibration dependence

P f (K),

where P is the pressure perceived by the sensor,

in terms of K, the pressing pressure existing in the stator core of the electric machine is determined.

Thus, the magnitude of the pressing force is determined by the value determined by the ratio of electric capacitances CffjH Wed, the reliability of the electric machine is increased by increasing the accuracy and reliability of diagnostics of the pressing state of the stator core, which is achieved by eliminating the influence on the measurement results of factors not directly dependent from pressing the stator core of an electric machine.

Claims (1)

Invention Formula The stator of an electric machine containing segments of iron core, pressure fingers, pressure flanges, nuts mounted on fixed wedges5 С 34271 nx and capacitive pressure sensors for pressing a core, each of which is installed between a nut and a pressure flange, and includes two insulated electrically conductive plates, characterized in that, in order to increase reliability by increasing accuracy and reliability 10 diagnostics of the state of pressing of the stator core during operation, each sensor is equipped with two additional insulated conductive plates, with two The 15 plates of the sensor are fixed on steel washers separated by an elastic ring, and are installed one relative to the other with a gap, and the other two plates are fixed in a steel sheet 20, the lateral surface of which covers the steel washers, and are also installed one with the other relative to the other.  . 2 With fie, 3 Editor T. Lazorenko Compiled by, Podolsk Tehred L. Serdyukova Proofreader G. Reshetnik Order 3974/52 Circulation 659 Subscription VNIIPI USSR State Committee on Inventions and Discoveries 113035, Moscow, Zh-35, Raushsk nab. 4/5 . Production and printing company, Uzhgorod, st. Project, 4