SU1684736A1 - Method of monitoring of process of hardening of impregnated insulation of windings of electrical engineering articles - Google Patents

Abstract

Inventors refer to microtechnical engineering and the technology used, for example, when controlling the process of disinfecting the impregnation of the electrical wiring of the electrical wiring 1. Periphemes of the invention - pneumatic TCIMHOCTII and simplification of control. In the proposed method, in addition to measuring the capacitance relative to the body before the impregnation and after impregnation and DRYING, at one of the frequencies, one of which is sensitive to the magnetic field, and the other is to the optical frequency domain, it means that the randomly selected non-impregnated winding of the batch is immersed in the same decid- ary i- with a known frequency dependence of the dielectric constant, a 1007 impregnation is simulated in the winding, the PMCh of which is measured on those LFRs often. max capacity relative to the body. All other windings are determined by the degree of curing according to the method described in the description of the invention. (L

Description

The invention relates to electrical engineering, in particular, to a method for manufacturing windings of electrical machines, transformers, and other winding products, and can be used in monitoring the curing process of impregnated electrical insulating insulation.

The purpose of the invention is to improve the accuracy of control and simplify the implementation of the method.

The dispersion for the impregnating composition, and KP-34, in the uncured state, lies in the frequency range of 100 Hz - 1-5 kHz, and at gyuch SHR frequencies of 5 kHz is optical. From m - the area where the dielectric constant constant At frequencies higher than 5 kHz, the dipole molecules of the liquid do not have time to orient themselves in time with the frequency of the field, as a result of which the dielectric constant remains after- (Tscnnaya. After polymerization of the impregnating composition of its molecule, the molecules become longer due to polymerization low frequencies of the field compared to the uncured state. Over the entire frequency range from 100 Hz to 1 MHz, the dielectric constant of the cured KP-34 impregnating composition remains unchanged, which is n is large CCs riionnostyu

About OS 4-

J

WITH

about

The molecules in the polymerization reaction process, which did not manage to cheat, synchronized with the frequency of the field.

The essence of the invention is as follows.

The capacity of the impregnated winding relative to the housing forms a complex system consisting of the enamel capacity C, the air gap capacity between conductors Cj, the body insulation capacitance C to and the air gap capacity between the body insulation and the housing connected in series o In the general case, capacity Cj and Ci are airborne, do not depend on the measurement frequency, and the capacitances Се and С may depend on the measurement frequency if the enamel materials and the body insulation are frequency-dependent. Therefore, the capacity of the impregnated winding relative to the case at frequencies f; (and f can be represented as expressions

one

one

one

one

(ABOUT

(2)

and a randomly selected winding, when measured at frequencies f and f, is caused, in accordance with expressions (3) and (4), by changing the value C with changing frequency.

Taking into account expressions (3), (4) and (5), we can write

Suppose that after immersing v the impregnating fluid with the known dielectric constant of this randomly chosen winding, the capacitance relative to the body is measured on. frequencies f and f. We denote by Cpc, the capacity of an arbitrarily selected winding relative to the body after simulating it with 100% impregnation immersion in an impregnating fluid at a frequency fj, and through - at a frequency f / j.

The following expressions are valid for this winding.

WITH

T 3rd

- the capacity of the same non-impregnated winding relative to the housing, measured at frequencies

in С „+ С

62

Imagine the capacitance C in the form of the product of the geometric Factor g 50 on the dielectric constant of air ЈСВ

8th

AT

(five)

Since the geometrical Factor g, | and the dielectric constant B do not depend on the frequency of the electric field; change capacitance value of pro (8)

35

(9)

0

five

0

five

where Ј {(, 6 (n values of the dielectric constant of the impregnating fluid with a known dielectric constant at frequencies f 4 and fЈ, respectively.

It is known that for single-type windings the ratio of

pg; 9p

permanently

and depends on the dielectric permeability of the impregnating fluid: • quick hygi Ј (. Since the dielectric constant (impregnating fluid depends on the frequency), for single-type windings the values are defined as defined by the ratio, and -; -.

Sn mr

If we take into account that with g is independent of frequency and is equal to 1, then taking into account expressions (.6), (7), (8) and (9), we get two systems of equations

By comparing this value with a predetermined value, the degree of curing of the windings is determined.

Claims (1)

Invention Formula A method of controlling the curing process of the impregnated insulation of the windings of electrical products, which consists in measuring the informative dielectric parameter of the test product at the first and second values of the excitation frequency, the first value of the frequency being chosen in the dispersion region, and the second value in frequency-independent region of the characteristics of the impregnating composition in the uncured state, characterized in that, in order to improve the accuracy and simplifying the implementation of the method, as an informative dielectric parameter, use the capacity of the controlled winding relative to the body of the electrical product being monitored, immerse the winding in a dielectric liquid with a known frequency dependence of the dielectric constant, measure the capacitance relative to the body at the first and second values after this dielectric liquid x excitation frequencies and the degree of cure of the impregnated windings are determined after a full about the completion of impregnation and drying according to the result of measurements of the capacity of these windings relative to the case at the first and second frequency values according to the formula: - ABOUT SH Cnlvl D "W --- (B (1 1) SPSH (C C de g or niV  P 9P1 g  pp - ten capacitances relative to the case of impregnation, measured respectively at frequencies f {and f dp of all controlled windings; capacitance relative to the body before impregnation, measured respectively at frequencies С {and f 1 ПЯ of a randomly selected winding from a batch; capacitances relative to the housing, measured at frequencies f and f for a randomly selected winding from the batch after simulating 100% impregnation in a liquid with a known frequency 15 20 25 -sv (n (e „-§5 C „I h g with (/ 4ni С n -р- With nni T nj one)  PP2. dependence of dielectric constant; containers relative to the hull after impregnation and drying, measured respectively at often5 0 five max and for all bm MI C (C controlled windings; dielectric permittivity values at the corresponding frequencies Ј,) and f "of the fluid, which imitates 100% impregnation in a randomly selected winding from the batch, the cure value of the degree of curing is compared with the reference ones and judging by the comparison result, it is judged on the quality of impregnation of the insulation.