JPS5833787B2 - linear induction motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to electrical machines, and more particularly to linear induction motors.

The invention can be used in transportation devices, conveyor lines, and other electrical devices featuring linear or reciprocating movement of actuators.

The invention is most effective for high speed ground vehicles that are suspended magnetically or by air cushions.

The most efficient interaction between the inductor and the secondary element of a linear induction motor to produce a propulsion force is distantly related to a purely sinusoidal distribution of the magnetizing force in the direction of movement.

Linear induction motors with an inductor made of separate U-shaped cores surrounded by lumped polyphase windings and a secondary element are known (UK Patent No. 1,37 of 1974).
(See No. 3,054).

The magnetic flux of the inductor of this known motor closes in a direction perpendicular to the direction of movement of the inductor, and the propulsion force is generated by the moving magnetic field present at that time.

However, the distribution of the magnetizing force in the longitudinal direction of this known motor differs significantly from a sinusoidal wave.

It comprises an inductor bounded by a row of laterally stacked main U-shaped cores, and a secondary element interacting with the inductor, said core being surrounded by a main distributed polyphase winding, and said secondary element being surrounded by a main distributed polyphase winding. Linear induction motors are also known which have a conductive part mounted on a magnetically conductive base (e.g. 19
B by VINITI Publishing House, Moscow, Soviet Union, 1975.
,M.

1 Linear Motor by Eisonstein (see page 61).

The inductor of this known motor is designed in such a way that the cores are arranged in rows with some distance from each other by an air gap.

In this case a toothed active region is formed, which causes a non-sinusoidal distribution of the magnetizing force in the direction of movement of the inductor.

This adversely affects the propulsion characteristics of this known motor.

Therefore, an object of the present invention is to increase the propulsive force of a linear induction motor.

This object comprises an inductor formed by a row of laterally stacked main U-shaped cores and a secondary element interacting with this inductor, said core being surrounded by a main distributed polyphase winding; and in a linear induction motor in which said secondary element has an electrically conductive portion mounted on a magnetically conductive base, further U-shaped cores stacked laterally are connected to said inductor in no more than two rows. , the further core is surrounded by a further distributed polyphase winding, and the further core has alternating legs of the main U-shaped core and the further U-shaped core. and the linear element is arranged between the main U-shaped cores so as to form two toothless active regions adjacent to each other, and the secondary element interacts with the inductor via the active region. Achieved by induction motor.

If only one row of the further U-shaped core is used in this linear induction motor, the further core is taller than the main U-shaped core and is arranged in one row with it. 2 is preferred.

In another embodiment of the invention, when the further U-shaped cores are used in two rows, the further cores are at the same height as the main cores and are of the same height as the main cores. placed on both sides.

The linear induction motor proposed here is easy to manufacture;
Large propulsive force and high efficiency.

The design of the linear induction motor according to the invention allows the inductor section to be easily repaired.

Hereinafter, specific examples of the present invention will be described in detail with reference to the accompanying drawings.

Here, we will consider the use of linear induction motors in high-speed ground vehicles.

Referring to FIG. 1, a linear induction motor according to the present invention comprises an inductor 1 comprising a main U-shaped core 2 stacked laterally and a further U-shaped core 2 stacked laterally.
These cores 2 and 3 are each surrounded by a main distributed polyphase winding 4 and a further distributed polyphase winding 5, and further the linear induction motor is interconnected with the inductor 1. It comprises an operative secondary element 6, which has an electrically conductive part 7 mounted on a magnetically conductive base 8.

Each main core 2 and each further core 3 has a yoke 9 and 10 and two legs 11 and 12, respectively.

In order to better understand the invention, FIG. 1 shows yet another linear induction motor with some of the U-shaped cores 3 broken away.

The further U-shaped core 3 is generally taller than the main U-shaped core 2 and is arranged in line with the main U-shaped core.

Legs 11 and 1 of each row of the main core 2 and further cores 3
2 are alternating and adjacent to each other form two active regions 13 without teeth, through which the secondary elements 6 interact with the inductor 1 .

The height of the further U-shaped core 3 is selected such that it is possible to fit the main winding 4 and the further winding 5 and an insulator (not shown) between them.

The main U-shaped core 2 and the further core 3 are made of electrical steel sheet, while their windings 4 and 5 are made of copper.

Aluminum is used as the material for the electrically conductive portion 7 of the secondary element 6, but copper or other materials with high electrical conductivity can also be used.

The magnetically conductive base 8 is made of a mechanical steel sheet, but if it is made of a mechanical steel sheet, an electrical steel sheet with improved magnetic properties can also be used.

Referring to FIG. 2, another practical example of a linear induction motor comprises an inductor 1 made of one row of main U-shaped cores 2 and two rows of further U-shaped cores 3, The cores 3 are of the same height as the main cores 2 and are arranged on either side of the row of main cores 2.

However, if the output of the motor is to be increased without changing the length of the motor, the number of rows of main cores 2 may be greater.

Each leg 11 and 12 of the main core 2 and further core 3 is alternated and forms two active areas 13 without teeth.

The linear induction motor according to the invention operates as follows.

When the main winding 4 and the further winding 5 (FIG. 1) are connected to a three-phase AC power supply (not shown), the current flowing therein forms a magnetizing force which causes the movement of the inductor. A moving magnetic field sinusoidally distributed in the toothless active region 13 is generated in the toothless active region 13.

This moving magnetic field induces an electromotive force and a current in the conductive portion 7 of the secondary element 6.

This current interacts with the moving magnetic field and generates a force that is guided along the secondary element 6.

These forces cause the inductor 1 to move in a direction opposite to the direction of the moving magnetic field (indicated by the arrow).

The linear induction motor of FIG. 2 operates similarly.

A further driving force in the direction of movement of the inductor is generated by the presence of the flanking active region formed by the legs 12 of the further rows of cores 3 not alternating with the main core 2, which contributes to good propulsion characteristics.

Because the distribution curve of the moving magnetic field in the direction of movement of the inductor approaches a sine wave, the propulsive force of the linear induction motor of the present invention is much larger than that of known linear induction motors. .

A large propulsive force means that the motor itself operates efficiently.

[Brief explanation of drawings]

FIG. 1 shows a linear induction motor in which further U-shaped cores are arranged in one row according to the present invention, and FIG. 2 shows a linear induction motor in which further U-shaped cores are arranged in two rows according to the present invention. FIG. 2 is a diagram showing a linear induction motor. 1... Inductor, 2... Main U-shaped core, 3... Yet another U-shaped core, 4...
・Main distributed polyphase winding, 5... Another distributed polyphase winding,
6... Secondary element, 7... Conductive part of secondary element, 8... Magnetically conductive part of secondary element, 11
...Core 2 leg, 12...Core 3
leg, 13... active area without teeth.

Claims (1)

[Claims] 1 comprising an inductor consisting of a row of laterally stacked U-shaped main cores and a secondary element interacting with the inductor, said core being surrounded by a main distributed polyphase winding, and said secondary element being surrounded by a main distributed polyphase winding; In a linear induction motor, the element has a conductive part mounted on a magnetically conductive base.
A further laterally stacked U-shaped core is provided in the inductor, this further core being surrounded by a further distributed polyphase winding and connecting the main U-shaped core with this further core. Said main U such that the legs with the U-shaped core are alternating and adjacent to each other forming two toothless active regions.
the secondary element interacts with the inductor through the active region, the further U-shaped core being positioned above and aligned with the main U-shaped core; A linear induction motor characterized by 1.