SU955384A1 - Electric machine magnetic circuit manufacturing method - Google Patents

Description

The invention relates to the technology of manufacturing magnetic circuits of electrical machines and can be used in electrical engineering and instrument making,

 A known method of manufacturing magnetic circuits of electrical machines, including the formation of a preform of a magnetic circuit with holes for accommodating the windings and the subsequent cutting of the slots G.

However, the known method is characterized by an insufficient quality of manufactured products due to the non-uniformity of the magnetic properties of the magnetic core material in the tooth zone of the machine. This leads to non-uniformity of the magnetic field in the working gap of the electric machine, for example, an electromechanical converter, and unfortunately its characteristics.

The purpose of the invention is to improve the quality of manufactured products by compensating for the heterogeneity of the magnetic properties of the magnetic core material in the tooth zone of the machine.

This goal is achieved by the fact that before slotting through the grooves, the magnetic resistances of the jumpers between the holes in the workpiece of the magnetic circuit are measured and the angular steps for slotting are determined according to the measurement data.

five .

FIG. 1 shows the magnetic circuit of an electric machine (stator of an electromechanical converter); in fig. 2 is a magnetic measurement circuit.

10 resistors of the interlayer between the holes in the preform.

In the general form of the equivalent magnetic resistance of the i-ro circuit of a magnetic circuit, for example, an electromechanical converter, the i-th pole and the corresponding air gap can be written as

ny

RI, RML. + where R§. - magnetic resistance

working gap;

20

 - the magnetic resistance of the magnetic circuit, adjacent to the i-th pole.

For uniform working clearance

can write

25

. R 1,

 K.S, - fUo

where S is the area of the i-ro pole; 30 K - coefficient taking into account

bulging and dissipating flows;

U (j is the magnetic permeability of air.

The heterogeneity of the magnetic properties of the material leads to the fact that for each i-ro circuit, the quantity / will be its own, distinct from the neighboring circuit. To ensure the quality of the electromechanical converter, it is necessary to ensure the condition of const

This condition can be fulfilled by making certain adjustments and Rg values, which would compensate for the spread of R values.

This can be accomplished by changing the value of S, which is formed during the slotting process. Since the size of the magnetic circuit and the direction of its main axis of inertia is constant, it is practically possible to influence only the width of the pole or, equivalently, the magnitude of the angular pole pitch.

in this case, the goal is to align the magnetic resistance of the sections of the magnetic circuit, therefore, information is needed only on the deviation of the RMI value from any section of the magnetic circuit that has been taken as the standard.

Given the above, the relative “and the magnitude of the angular pitch of the i-ro pole can be written

ot

8+ KfUoSgCRMa- V) where the angular. Step of the selected reference contour.

The choice of value must ensure that the conditions

f U; + oi, -2,. ,

where Y is the angular width of the i-ro slot; dd „is the minimum value for y for this converter.

Thus, the measurement of R values, before slotting, can be made by adjusting the oi values. to ensure in the manufacturing process of the magnetic circuit itself to compensate for the inhomogeneity of the magnetic properties of the material of the magnetic circuit.

The method is carried out as follows.

The stator of the electromechanical transducer (Fig. 1) has a magnetic core 1 with holes 2 for positioning the windings and grooves 3 forming poles 4.

In the first operation, a preform of the magnetic core with openings for the placement of the windings is formed. In the second operation, the magnetic resistances of the jumpers between the holes in the preform of the magnetic core are measured (Fig. 2). To do this, using a conductor 5 connected to an AC mains, an alternating magnetic flux is created in the magnetic conductor and the emf induced in the windings b and 7 is measured, covering the jumpers in the magnetic conductor between the holes.

If the excitation for all sections of the magnetic circuit is performed by the same current, and the windings on the jumpers have the same number of turns, then the EMF value in the i-th winding uniquely characterizes the value of Ryirt.

In the next operation, a slotting operation is performed according to the measurement data. Slotting may be possible. exist on digital program-controlled machines.

The use of the invention allows to improve the quality of manufactured products by compensating for the heterogeneity of the magnetic properties of the magnetic circuit in the tooth zone of the electric

cars.

Claims (1)

1. Rybkin L, I. and others. Ferrites. L., Energie, 1968, p. 101. diL fL-