JPH02133004A - Linear motor for vehicle - Google Patents

Abstract

PURPOSE:To reduce reactive power and contrive the energy saving of an inverter device by making the value of an air gap the same as the value of a magnetic air gap. CONSTITUTION:A slender plate 20, made of iron and lined with a magnetic body, is laid on the road bed 2 of a track 1 while projected magnetic pole cores 21 are provided on the plate 20 so as to be arranged with a constant pitch. A short-circuit coil 22, made of a non-magnetic conductor, is attached to respective projected magnetic pole cores 21. A primary side 6, as the non- magnetic conductor of a linear motor, is provided at the side of a trucks 5, integral with a body opposed to respective short-circuit coils 22, so that a relation between a primary side pole pitch tau and the mounting pitch L of respective projected pole cores 21 becomes 0.5tau<=L<=1.5tau. According to this method, the power factor of the linear motor may be improved.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a linear motor for a vehicle used, for example, in a linear motor train driven by a single-sided linear motor (linear induction motor). .

(Prior technology) Linear motors for vehicles of linear motor trains, which are driven by single-sided linear motors as medium-duty transportation in new transportation systems, are equipped with reaction plates (secondary side) on the track side,
The primary side of a linear motor (LIM main body), which corresponds to the primary side (stator) of a rotary induction motor, is mounted on the bogie side of the car body, and this linear motor electric train uses electromagnetic induction as propulsion force. It is designed to run on orbit.

A linear motor for a linear motor train, which has already been proposed and is driven by a single-sided linear motor of this type, is constructed as shown in FIGS. 11 and 12.

That is, in FIGS. 11 and 12, on the track bed 2 on the track 1 side, a secondary side (reaction plate) 3 made of a non-magnetic conductive plate of a single-sided linear motor is integrated with a magnetic backing plate 3a. It has been laid down
A primary side 6 of the linear motor is provided on the side of the bogie 5 that supports the vehicle body 4, facing the secondary side 3. Further, each axle 9 integral with each wheel 8 is mounted on the bearing 7 of the truck 5, and each axle 9 is attached with each mounting base (not shown). Further, on each mounting base, a pair of holding members 10 are attached to the coils 11 constituting the primary side 6.
are arranged in parallel so as to fix the laminated cores 12 equipped with the coils 1. On the outside of each of the holding members 10, a cover member 13 which also serves as a ventilation duct is provided to prevent the primary layer of the laminated core 12 equipped with the coils It is formed and provided so as to surround the side 6 from the outside.

Therefore, during running, the linear motor for a linear motor train as mentioned above is activated by energizing the single-sided linear motor 6 to prevent the secondary side (reaction plate).
3 and the primary side 6 of the linear motor corresponding to the primary stator
It is designed to travel on orbit 1 using the propulsion force generated by the electromagnetic induction effect.

In other words, when a linear motor for a single-sided linear motor train is running, eddy currents are induced in the secondary side (reaction plate) 3 by the linkage magnetic flux generated on the primary side 6 of the linear motor, and these It runs on orbit 1 using the propulsion force generated by electromagnetic induction.

On the other hand, the magnetic backing plate 3a, which is integrated with the secondary side (reaction plate) 3 of the linear motor, forms a circulating magnetic circuit for the interlinkage magnetic flux generated on the primary side 6, and the single-sided linear motor train The aim is to improve the characteristics of linear motors for vehicles, such as improving the power factor.

In other words, the secondary side of the linear motor (reaction plate)
3, as diagrammatically shown in FIG. 12, the air gap (mechanical gap) A between the primary side 6 and the secondary side (reaction plate) 3 of the linear motor is The length of the air gap between the iron core surface and the secondary side (reaction plate) 3 is the same as the length of the air gap between the iron core surface and the secondary side (reaction plate) 3. In order to form a circulating magnetic circuit, the magnetic backing plates 3a are superimposed, and the distance (magnetic gap) between the primary side 6 of the linear motor and the magnetic backing plate 3a is
Depending on the magnitude of B, the power factor of the primary side 6 changes greatly, as shown in the graph of FIG.

That is, as shown in the graph of FIG. 13, the smaller the magnetic gap B between the linear motor primary side 6 and the magnetic backing plate 3a, the larger the power factor of the primary side 6 becomes. As a result, the interlinkage magnetic flux generated on the primary side 6 of the linear motor is circulated and transmitted to the magnetic backing plate 3a, thereby reducing leakage reactance.

On the other hand, in a linear motor for a single-sided linear motor train, the air gap A is usually about 10 mm, and the secondary side 3 formed by the non-magnetic conductive plate
Since the thickness t of the magnetic gap B is about 5 mm, the magnetic gap B
The length is about 15 millimeters. At this time, the power factor of the primary side 6 of the linear motor is approximately 60%, compared to the power factor of a general rotary motor which is approximately 80%.
Due to the fairly low power factor, a large amount of reactive power flows through the inverter device on the power supply side, which causes heat generation in various electric elements, causing damage to the linear motor for single-sided linear motor trains. It is desired to improve the power factor.

(Problem to be Solved by the Invention) However, in the configuration of the secondary side (reaction plate) 3 of the linear motor in the linear motor train described above, the magnetic air gap B is divided by the air gap A and the nonmagnetic conductive plate. It is the sum of the thickness t of the downstream side 3, and it is impossible to bring this magnetic air gap B to the minimum value allowed by the air gap A, and it is difficult to improve the power factor of the primary side 6 of the linear motor. This not only makes it difficult to achieve energy savings, but also causes problems such as reducing the weight of various electrical devices in the inverter device and reducing operating efficiency due to the heat generated by the linear motor in a linear motor train.

The present invention has been made in view of the above-mentioned circumstances, and aims to improve the power factor characteristic of the primary side of the linear motor while leaving the output on the primary side of the linear motor unchanged. It is an object of the present invention to provide a linear motor for a vehicle in which the generated interlinkage magnetic flux is circulated and transmitted to the magnetic lining plate to reduce leakage reactance and to improve operating efficiency. .

[Structure of the invention]

(Means for Solving the Problems and Their Effects) The present invention provides a primary side of a single-sided linear motor on the bogie side,
In a linear motor electric train with a secondary side on the track side facing the primary side, an elongated magnetic backing plate is laid on the track side, and each convex shape is placed on this magnetic backing plate at a constant pitch. The magnetic pole cores are arranged side by side, and a short-circuiting coil made of a non-magnetic conductor is attached to each convex magnetic pole core to make the air gap and the magnetic air gap the same.Moreover, the output of the primary side of the linear motor can be maintained as is. In addition to improving the power factor characteristics on the primary side, the magnetic flux linkage generated on the primary side of the linear motor is circulated and transmitted to the magnetic lining plate to reduce leakage reactance. be.

(Example) An embodiment of the present invention will be described below.

Note that the present invention will be described with the same reference numerals given to the same constituent members as in the above-described specific example.

In FIGS. 1 to 3, reference numeral 1 denotes a track in a single-sided linear motor, and a trackbed 2 on the side of the track 1 is provided with an elongated magnetic backing plate 20 made of iron, for example. , this magnetic backing plate 2
0, each convex magnetic pole core 21 is arranged in a row at a constant pitch, and each convex magnetic pole core 21 is connected to the magnetic backing plate 20 as shown in FIG.
It is fixed on the top with each mounting member 23. Further, each of the convex magnetic pole cores 21 is equipped with a shorting coil 22 made of a non-magnetic conductor such as copper or aluminum, and each shorting coil 22 is wound with one or more coils. Each of the convex magnetic pole cores 21 is mounted thereon.

On the other hand, a primary side 6 as a non-magnetic conductor of the linear motor is provided on the side of the bogie 5 that is integral with the car body and faces each of the short-circuited coils 22 as the secondary side of the linear motor. The relationship between the pole pitch τ on the side 6 and the mounting pitch L of each convex magnetic core 21 is set such that 0.5τ≦L≦1.5τ.

This is because when L<0.5τ or L>0.5τ, the flow of eddy current decreases, and in order to improve the characteristics of the primary side 6 of the linear motor, 0.5τ≦L≦1.5τ. It is hoped that this will happen.

Therefore, during running, the linear motor for a linear motor electric train described above can short-circuit each of the magnetic material lining plates 20, which serve as the secondary side (reaction plate), by energizing the primary side 6 of the linear motor. The primary side 6 of a linear motor corresponding to the coil 22 and the primary side (stator)
It is designed to travel on orbit 1 using the propulsion force generated by the electromagnetic induction effect.

In other words, when the linear motor for a single-sided linear motor train is running, the magnetic flux linkage generated on the primary side 6 of the linear motor causes the above-mentioned magnetic backing plate 20 as the secondary side (reaction plate) to Eddy currents are induced in each of the short-circuited coils 22, and the vehicle travels on the track 1 with the propulsion generated by these electromagnetic induction effects.

Next, the present invention shown in FIG. 4(A) and the already proposed linear motor for a single-sided linear motor train shown in FIG. 4(B) will be explained using mathematical formulas.

The magnetic air gap g2 in the already proposed linear motor for vehicles shown in FIG. 4(B) is the sum of the air gap A and the thickness t of the primary side 6 as a non-magnetic conductor, that is, g2- A+t・・・・・・・・・・・・・・・・・・
...(1).

On the other hand, in the present invention shown in FIG. 4(A), the magnetic gap g1 is g1 -A .
...(2).

Therefore, from the above equations (1) and (2), gl""g2 j・・・・・・・・・・・・・・・
...(3).

That is, the magnetic gap g1 of the present invention shown in FIG. 4(A)
can be made smaller by the thickness t of the secondary side 3 as the non-magnetic conductor than the magnetic gap g2 in the already proposed linear motor for vehicles shown in FIG. 4(B). can.

As described above, according to the present invention, the power factor in a linear motor for a vehicle is improved. That is, as shown in the graph of FIG. 5, the relationship between the "efficiency and slip" of the present invention and already proposed linear motors for vehicles is only slightly better; As shown in the graph,
The combination of the present invention and already proposed linear motors for vehicles
In the present invention, the relationship between the power factor and the slip is as follows when the slip is 1.0, compared to the already proposed linear motor for vehicles.
Approximately twice as much, even in the commonly used slip area (about 0.3), it is approximately 10
% better.

Next, another embodiment of the present invention shown in FIG. 7 is one in which each convex magnetic pole core 21 is substantially integrated on the magnetic backing plate 20, and is different from the specific example described above. It's the same thing.

On the other hand, in another embodiment of the present invention shown in FIGS. 8 and 9, in order to improve the power factor characteristics, the area of each convex magnetic pole core 21 facing the primary side 6 of the linear motor is reduced. The air gap A is made large and the magnetic gap B is made the same to improve the power factor.

Further, in another embodiment of the present invention shown in FIG. 10, the magnetic backing plate 20 and each convex magnetic pole core 21 are inclined by an angle θ with respect to the primary side 6 of the linear motor. This reduces the throttle ripple with the primary side 6 of the linear motor, and also makes the air gap A and the magnetic gap B the same to improve the power factor. It is.

In addition, in the present invention, it is free to unitize each of the convex magnetic pole cores 21 and the short circuit coil 22 in advance.

〔Effect of the invention〕

As described above, according to the present invention, since the air gap A and the magnetic gap B are configured to be the same, the output of the primary side 6 of the linear motor remains unchanged, and the power factor of this primary side 6 is Since it is possible to improve the characteristics, it is not only possible to reduce reactive power and save energy in inverter equipment, but also to suppress heat generation in the electrical equipment used, improve reliability, and improve linear The leakage reactance can be reduced by circularly transmitting the interlinkage magnetic flux generated on the primary side 6 of the motor to the magnetic lining plate 20, and furthermore, the present invention can reduce the leakage reactance of the linear motor by the reduced excitation current. Since the temperature rise on the primary side 6 can be suppressed, the life of the insulating material used for the short-circuiting coil 20 and the like can be extended, and reliability and safety can be improved.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing only the essential parts of the linear motor for a vehicle according to the present invention, FIG. 2 is a perspective view showing only the essential parts of the linear motor for a vehicle according to the present invention, and FIG. Chain line A-A in the middle
4(A) and 4(B) are diagrams for explaining the action of the present invention and the previously proposed vehicle linear motor, and FIG. FIG. 6 is a graph showing the relationship between the power factor and slip of the linear motor for vehicles that has been proposed in the present invention and the linear motor for vehicles that has already been proposed.
7 to 10 are diagrams showing other embodiments of the present invention, FIG. 11 is a sectional view of a linear motor for a vehicle that has already been proposed, and FIG. 12 is a sectional view of a linear motor for a vehicle that has already been proposed. FIG. 13, which is a diagram for explaining the action of the linear motor for vehicles, is a graph showing the relationship between the power factor and the magnetic gap of the already proposed linear motor for vehicles. DESCRIPTION OF SYMBOLS 1... Track, 5... Bogie, 6... Primary side of linear motor, 20... Magnetic material lining plate, 21... Convex magnetic pole core, 22... Short circuit coil.

Claims (1)

[Claims] In a linear motor train in which the primary side of a single-sided linear motor is installed on the bogie side and the secondary side is installed on the track side opposite to this primary side, an elongated magnetic backing plate is laid on the track side. A linear motor for a vehicle, characterized in that convex magnetic pole cores are arranged on a magnetic backing plate at a constant pitch, and a short-circuit coil made of a non-magnetic conductor is attached to each convex magnetic pole core.