JPH0315401B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for inspecting a ground coil of a linear synchronous motor for a vehicle, which is suitable for driving a magnetically levitated ultra-high-speed vehicle.

So-called linear motor vehicles, which use linear motors as the drive source for vehicle propulsion and braking, can obtain large driving force regardless of the adhesive force between the wheels and the rails, and have almost no moving parts in the drive system. In addition to the above advantages, magnetic levitation is easy to apply, especially for vehicles using linear synchronous motors, so it is attracting attention as a drive source for ultra-high-speed vehicles. .

Such a linear synchronous motor (hereinafter simply
Figure 1 schematically shows an example of a magnetically levitated ultra-high-speed vehicle using an LSM.

In the figure, 1 is an ultra-high-speed vehicle, 2 is an LSM field coil, and 3 is an LSM armature coil (referred to as a ground coil) installed on the ground along the track of the vehicle 1.

The field coil 2 is composed of a superconducting coil or the like in order to generate a strong magnetic field, and the vehicle 1 is magnetically levitated by the electromagnetic repulsion force acting between it and the ground coil 3 installed correspondingly. The moving magnetic field generated by the ground coil 3 generates a linear driving force independent of the adhesion effect, and the vehicle 1 is propelled. Note that in this type of vehicle, the field coil 2 is provided on the vehicle 1, so it is called an on-vehicle field type.

Therefore, according to this on-board field type LSM car,
Since the vehicle 1 is floating and a sufficiently large propulsion force is obtained without being limited by the adhesion effect, the vehicle can run at extremely high speeds.

By the way, in such an on-board field type LSM vehicle, the ground coil 3, which is the armature coil of the LSM, is installed over almost the entire track, so the ground coil 3 is exposed to various objects such as pebbles. They are susceptible to damage from collisions, and there is a possibility of problems such as interlayer short circuits, ground faults, bridges at the coil outlet terminals, and disconnections due to deterioration of the coil insulation.

Therefore, in such a system, monitoring work such as inspection and inspection of the ground coil 3 is essential.For this reason, conventionally, when the LSM vehicle stops operating, DC current is passed through the ground coil 3, and the direction magnet (magnetic compass) The method that has been mainly adopted is to sequentially detect the magnetic flux generated by the ground coil 3 using a ground coil 3 for inspection.

However, with this method, the inspection is done manually, and it is necessary to proceed with the work while checking each ground coil 3 for each unit (for example, for each phase), which requires a great deal of labor and time. There were flaws.

An object of the present invention is to eliminate the drawbacks of the prior art described above, and to provide a vehicle for ground coils that can be easily inspected in a short period of time with almost no manual labor required.
To provide an LSM ground coil inspection method.

In order to achieve this object, the present invention provides a magnetic flux detection device capable of continuously detecting magnetic flux on a moving means capable of traveling along the track of an LSM vehicle, and provides the above-mentioned It is characterized in that the ground coil is inspected by running the moving means.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a ground coil inspection method for a vehicle LSM according to the present invention will be described below with reference to the drawings.

First, FIG. 2 shows an example of a magnetic flux detection device used in an embodiment of the present invention. In the figure, 4 is a light source, 5 is a polarizer, 6 is a polarization preserving optical fiber, and 7 is a detector. Photon 8 is a photoelectric conversion unit. Note that 9 represents the entire magnetic flux detection device.

The light source 4 is composed of an incandescent lamp, an LED, or the like, and functions to send a predetermined, substantially constant amount of light into the optical fiber 6 via the polarizer 5.

The polarizer 5 is composed of a Nicol prism, a polarizing filter, etc., and functions to align the plane of polarization of the light sent from the light source 4 into the optical fiber 6 in one predetermined direction.

The optical fiber 6 is a so-called polarization-maintaining optical fiber.General optical fibers can only transmit light when the plane of polarization is random, but this polarization-maintaining optical fiber propagates light with the plane of polarization preserved. It has the property of being possible. Therefore, the optical fiber 6 functions to transmit the polarized light incident from the light source 4 through the analyzer 5 from one end face to the other end face while preserving the polarization plane P, and in the meantime, in the direction of arrow B in the figure. When a magnetic field is applied, the plane of polarization rotates due to the Faraday effect, and the polarized light enters the analyzer 7 with the angle of rotation of the plane of polarization caused by the magnetic field unchanged.

The analyzer 7 has a plane of polarization that is perpendicular to the plane of polarization produced by the polarizer 5, and corresponds to the rotation angle θ of the plane of polarization given in proportion to the strength of the magnetic field by the Faraday effect in the optical fiber 6. It works by allowing only a certain amount of light to pass through.

The photoelectric conversion unit 8 includes a photocell, a photodiode, a phototransistor, etc., and an analyzer 7.
The function is to generate a detection signal according to the amount of light that has passed through the sensor.

As a result, the magnetic flux detection device 9 generates an electric signal representing the strength of the magnetic field applied in the direction of the arrow in the figure, and can detect the magnetic flux.

Next, an embodiment of the present invention using this magnetic flux detection device 9 is shown in FIG.

In FIG. 3, reference numeral 10 denotes a moving vehicle for inspection that can run along the track of the LSM vehicle, in which a magnetic flux detection device 9 is attached so that the optical fiber 6 is vertical, and a photoelectric conversion unit 8 is installed. The electrical signals obtained from the sensor can be continuously monitored using a suitable meter or the like. Further, this mobile vehicle 10 is made to be able to travel by a drive source independent of the LSM, of which the ground coil 3 is a part, such as an internal combustion engine.

When inspecting the ground coil 3, as shown in Fig. 4, an appropriate DC power source 11 is connected to the ground coil 3 so that DC current flows through all the ground coils 3 within a predetermined section. . Then, from each of the ground coils 3, the third
A magnetic field as shown in the figure will be created.

Next, while the moving vehicle 10 is running along the track where the ground coil 3 is installed, the detection signal from the photoelectric conversion section 8 of the magnetic flux detection device 9 is monitored, as shown in FIG. As in, moving vehicle 10
As it travels and passes over each ground coil 3 one after another, a detection signal whose strength corresponds to the amount of magnetic flux generated by each ground coil 3 is obtained. As long as there is no abnormality in 3, it should be at almost the same level.

However, due to collision with an object, the ground coil 3
Interlayer short circuit due to deterioration of interlayer insulation,
If a bridge occurs at the output terminal, the effective number of turns of the coil in the ground coil 3 where an abnormality such as a short circuit or a bridge has occurred will decrease (in case of a bridge, it will become zero). As a result, the amount of magnetic flux generated is smaller than that of other normal ground coils 3, so the moving vehicle 10 is placed on top of the ground coil 3 where the abnormality has occurred.
As shown in FIG. 5, the level of the detection signal suddenly drops.

Therefore, according to this embodiment, a ground coil in which an abnormality has occurred can be detected by simply monitoring the signal from the magnetic flux detection device 9 while the mobile vehicle 10 is traveling, so that the ground coil inspection can be carried out in a short time. , and can be done reliably.

In this embodiment, the detection signal from the magnetic flux detection device 9 is monitored in real time, but a recording instrument using paper tape or the like is used to record the level of the detection signal together with the traveling position of the mobile vehicle 10. It may also be recorded.

At this time, the ground coil can be easily inspected by checking the records on paper tape or the like after the mobile vehicle 10 has traveled, and the ground coil in which an abnormality has occurred can be detected.

Further, in the above embodiment, a Faraday effect type magnetic flux detection device 9 using a polarization preserving optical fiber 6 is used, thereby achieving high detection sensitivity and stable and reliable detection operation. The embodiments are not limited to this, and can be implemented using any magnetic flux detection device. For example, various semiconductor magnetic sensors such as Hall elements and magnetic diodes may be used, and an appropriate magnetic circuit may be added thereto. Needless to say, it is good.

As explained above, according to the present invention, manual inspection can be significantly reduced.
It is possible to provide a ground coil inspection method for a linear synchronous motor for a vehicle, which eliminates the drawbacks of the prior art and allows easy and reliable inspection of the ground coil in a short period of time.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram conceptually showing an example of a magnetically levitated ultra-high-speed vehicle using a linear synchronous motor.
The figure is an explanatory diagram showing an example of a magnetic flux detection device applied to an embodiment of the present invention, FIG. 3 is a schematic diagram showing an embodiment of the present invention, and FIG. 4 is a schematic diagram for explaining the operation thereof. FIG. 5 is a waveform diagram as well. 3... Ground coil, 4... Light source, 5... Polarizer, 6... Polarization preserving optical fiber, 7... Analyzer, 8... Photoelectric conversion section, 9... Magnetic flux detection device, 1
0...Moving car, 11...DC power supply.

Claims (1)

[Scope of Claims] 1. In a vehicle running system driven by an on-board field type linear synchronous motor, there is provided a means for supplying direct current to a ground coil of the linear synchronous motor, and a drive means other than the linear synchronous motor to drive the ground coil. 1. A ground coil inspection method for a linear synchronous motor for a vehicle, comprising: a moving means capable of traveling along the ground coil; and a magnetic flux detection means installed on the moving means capable of detecting magnetic flux generated by the ground coil. 2. A ground coil inspection method for a linear synchronous motor for a vehicle according to claim 1, characterized in that the magnetic flux detection means is constituted by a Faraday effect type magnetic flux detection device using a polarization preserving optical fiber.