JPH0530609A - Thrust compensating system for linear induction motor car - Google Patents

Abstract

PURPOSE:To suppress fluctuation of thrust due to the temperature variation of ground reaction plate by correcting the secondary resistance or a slip frequency command of an onboard motor to a high level according to the linking order of vehicles composing a train. CONSTITUTION:A train is composed of vehicles 1-N numbered from the head vehicle in the traveling direction. The vehicle number N is inputted to an input unit 315 and a secondary resistance correcting block 316 corrects the secondary resistance of a linear induction motor 314 to a high value corresponding to the number N and thus corrected value is then fed to a block 311. The block 311 determines a slip frequency command fs from a thrust command F fed from an operator. An output signal fm from a vehicle speed sensor 41 is added to the slip frequency command fs to produce a frequency command fi which is then fed to a modulator 312 in order to control a VVVF inverter 313 which produces an output for driving the linear induction motor 314. Consequently, temperature rise of a reaction plate is suppressed when a train passes thus averaging the thrust of vehicles composing a long train.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an on-vehicle primary coil type linear induction motor drive by a variable frequency variable voltage inverter (hereinafter abbreviated as VVVF inverter),
This is to compensate for variations in thrust characteristics due to temperature.

[0002]

2. Description of the Related Art FIG. 2 shows a configuration of an on-vehicle primary coil type linear induction motor car when N cars are formed. Reference numeral 1 represents the entire first linear motor car in the traveling direction, 11 represents a linear motor iron core, 21 represents a linear motor coil, 31 is a VVVF inverter, and 41 is a vehicle speed sensor. 10 indicates a reaction plate. The second and subsequent cars are also the same as the first car. In the N-th car, N indicates the entire linear motor car of the N-th traveling direction, 1N indicates the iron core of the linear motor, 2N indicates the coil of the linear motor, and 3N indicates VV.
It is a VF inverter and 4N is a vehicle speed sensor.

The coil 21 constitutes a multi-phase connection, and a plurality of coils 21 are installed in the vehicle traveling direction as shown in the drawing. However, since the details of the configuration have nothing to do with the gist of the present invention, the concept is shown. Stay. These coils are powered by the VVVF inverter 31. The direction of the current of the coil of one phase is distributed with different polarities and magnitudes depending on the position in the traveling direction, as shown by the mark (from the paper surface to the front) and the cross mark (from the paper surface to the paper) in Fig. 2. To do. In FIG. 2, the broken line indicates the loop and direction of the main magnetic flux generated by the current in the coil. That is, the main magnetic flux passes through the air gap from the iron core, then passes through the reaction plate 10 (metal body), passes through the air gap again, and returns to the iron core. The reaction plate 10 is fixed on the ground.

As a means for holding the entire linear motor car 1 in the air and providing a gap between the iron core 11 and the reaction plate 10, wheels are used as in a levitation electromagnet or an ordinary railroad not shown in FIG.

Now, when the main magnetic fluxes are superposed with the respective phase components generated by the respective phase currents, a substantially constant composite magnetic flux proceeds at a speed according to the frequency and phase sequence of the VVVF inverter 31.
This corresponds to the rotating magnetic field of the rotary induction motor, and the secondary current is correspondingly generated by the reaction plate 10
A thrust force (corresponding to torque) is generated by the product of the secondary current and the magnetic flux, and the entire linear motor car 1 is propelled by the reaction force from the reaction plate 10. In order for the secondary current to flow, a speed difference is required between the speed of the traveling magnetic field and the speed of the entire linear motor car 1, which corresponds to the slip frequency.

The relationship between thrust and slip frequency is represented by f _s = K (R ₂ · F) / φ ² (1), where f _s ; slip frequency [Hz] R ₂ ; secondary resistance (reaction Equivalent resistance of plate)
[Ω] K; constant F; thrust [N] φ; strength of main magnetic flux [T].

Various methods have been proposed for controlling the VVVF inverter, but here, the strength φ of the main magnetic flux is made constant by making the voltage and frequency of the VVVF inverter output (ie, primary motor primary coil input) almost proportional. Then, the slip frequency f _s required to generate the desired thrust F is given by the equation (1). In this case, equation (1) is expressed as equation (2) using the command value (marked with *). f _s ^* = K (R ₂₀ · F ^* ) / φ ² (2) where, f _s ^* ; slip frequency command F ^* ; thrust command R ₂₀ ; secondary resistance R given to the VVVF inverter controller
It is the data of ₂ .

FIG. 3 is a control block diagram of the VVVF inverter 31 for energizing the linear induction motor car of FIG. The thrust command F ^* given by the driver
311 is converted into the slip frequency command f _s ^* shown in equation (2). f _s ^* is added to the output signal f _m of the vehicle speed sensor 41 and becomes the frequency command f _i ^* of the VVVF inverter. f _i ^* = f _s ^* + f _m (4)

The modulator 312 generates a switching signal to be supplied to the VVVF inverter 313, which is controlled by the frequency command f _i ^* and the voltage command V _i ^* . Actually VV
A means for keeping the switching frequency of the VF inverter within a substantially constant range, a means for stabilizing against disturbance, etc. are required, but especially essential control variables are the frequency command f _i ^* and the voltage command V _i ^*. Is one. For generation of the voltage command V _i ^* Also, to obtain approximately the intensity φ constant flux, requires a means for proportionally the frequency instruction f _i ^* and the voltage command V _i ^*, which are well known The description of this technology is omitted.

The output of the VVVF inverter 313 is supplied to a linear induction motor (RIM) 314.

[0011]

[Problems to be Solved by the Invention] Reaction plate
10 is fixed on the ground, on which trains pass. Aluminum alloys or copper alloys used for reaction plates have a high temperature coefficient of resistance, so the temperature rises each time the vehicle passes and the secondary resistance R in equation (1)
₂ changes. Data R _{20 of the} secondary resistance R ₂ given to the VVVF inverter controller with respect to the planned thrust command F ^*
Unless V is updated, the slip frequency f _s ^* commanded to the VVVF inverter 313 becomes an incorrect value, and as a result, the thrust F
Is different from the thrust command F ^* .

For example, when the material is copper, the relationship between resistance and temperature is R '/ R = (234.5 + t') / (234.5 + t) (3) where R: resistance value at temperature t R '; temperature t It is the resistance value at ′. When t = 0 ° C. and t ′ = 50 ° C., R ′ / R = 1.21, and the actual thrust value fluctuates by 21% for the same thrust command. The present invention is intended to prevent such an unexpected change in the thrust value due to the change in the temperature of the reaction plate 10.

[0013]

It is possible to make the thrust control insensitive to the fluctuation of the secondary resistance R ₂ to some extent, but it requires a considerably complicated process. In the case of a rotary induction motor, the secondary conductor is located in the center of the main body where the secondary conductor is almost sealed, heat dissipation is difficult, and the temperature rise is 200 ° C under heavy load.
It is said that the secondary resistance changes 80%. However, in the case of the on-vehicle primary coil type linear induction motor to which the present invention is applied, the heat radiation of the secondary conductor is good, and the heat generation period is only at the moment when the vehicle passes, so the temperature when one vehicle passes It is possible to make a sufficient correction by obtaining the rise in advance and setting the secondary resistance data R ₂₀ to a larger value in the rearward vehicle.

A thrust compensation system for a linear induction motor car according to the present invention based on the above technical concept is a thrust control of a linear induction motor car system by a variable frequency variable voltage inverter having a coil on the vehicle and a reaction plate on the ground. In the above, the secondary resistance value is corrected according to the number N in the order from the leading vehicle in the traveling direction of the vehicle.

Alternatively, in thrust control of a linear induction motor car system with a variable frequency variable voltage inverter having a coil on the vehicle and a reaction plate on the ground, a number N from the leading vehicle in the traveling direction of the vehicle is assigned. Accordingly, the slip frequency command may be corrected to a high value.

[0016]

[Function] The sliding frequency command f _s ^* given to the VVVF inverter is corrected in proportion to the data R ₂₀ of the secondary resistance R ₂ given to the VVVF inverter controller so that the thrust F becomes close to the thrust command F ^*. Act on.

The slip frequency f _s ^* is the data R ₂₀
It goes without saying that the correction may be made directly by the number N without the procedure of correction of No.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a control block diagram of a VVVF inverter for energizing a linear induction motor car according to the present invention based on such a technical idea. Blocks having the same functions as those of FIG. It is indicated by. A feature of the control block diagram shown in FIG. 1 is that a secondary resistance correction block 316 for correcting the data R ₂₀ of the secondary resistance R ₂ given to the VVVF inverter controller is added according to the equation (3). This secondary resistance correction block 316 has a discriminator with a number N.
From 315, the number N in the order from the leading car in the direction of travel of the train is supplied.

The number N, which is the order from the top car in the traveling direction of the train, is input when the train formation is confirmed. Also, when the traveling direction is changed, the order is reversed, but this can be easily changed.

[0020]

According to the present invention, in the control system that directly or indirectly uses the slip frequency for the thrust control of the linear induction motor, a minor addition to the extent that the vehicle connection order number is given. It is possible to obtain a thrust control characteristic which is practically uniform with respect to a linear motor car of a long formation.

[Brief description of drawings]

FIG. 1 is a control block diagram of a VVVF inverter for energizing a linear induction motor car according to the present invention.

FIG. 2 is a diagram showing a configuration of an on-vehicle primary coil type linear induction motor car.

FIG. 3 is a control block diagram of a conventional VVVF inverter for energizing the linear induction motor car of FIG.

[Explanation of symbols]

1 Linear motor car 10 Reaction plate 11 Linear motor iron core 21 Linear motor coil 31 V VVF inverter 41 Vehicle speed sensor 312 Modulator 313 VVVF inverter 314 Linear Induction Motor (RIM) 315 Vehicle number N input device 316 Secondary resistance compensation block

Claims (2)

[Claims] 1. A thrust control of a linear induction motor car system using a variable frequency variable voltage inverter having a coil on the vehicle and a reaction plate on the ground,
A thrust compensation system for a linear induction motor car, characterized in that the secondary resistance value is corrected to a high value in accordance with the number N in the order from the leading vehicle in the traveling direction of the vehicle. 2. A thrust control of a linear induction motor car system using a variable frequency variable voltage inverter having a coil on the vehicle and a reaction plate on the ground,
A thrust compensation method for a linear induction motor car, characterized in that the slip frequency command is corrected to a high value according to the number N in the order from the leading vehicle in the traveling direction of the vehicle.