JPH0447522B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an inverter device for a train, and particularly to an inverter device for a train suitable for reducing electromagnetic induction noise.

[Background of the invention] With the recent development of large-capacity gate turn-off thyristors (hereinafter referred to as GTO thyristors), inverter-controlled trains that use an induction motor as the main motor and control it with a GTO thyristor inverter device have come into practical use. Summer. This method controls the rotational speed of an induction motor by continuously changing the output frequency and output voltage of an inverter device (variable frequency variable voltage).

FIG. 1 shows an example of the main circuit configuration of an electric train controlled by an inverter device.

In Figure 1, 1 is an overhead wire, 2 is a pantograph,
3 is a filter reactor, 4 is an inverter device,
Numerals 6 to 17 are inside the inverter device 4, 5 is a filter capacitor, 6 to 11 are GTO thyristors, and 12 to 17 are freewheel diodes. 18 is an induction motor, and 19 to 21 are load lines of the induction motor. The operation of the inverter is well known and will not be described here.

Now, in an inverter-controlled electric train, the inverter device 4 and the induction motor 18 are usually installed under the floor, and the wirings 19 to 21 thereof are also arranged under the floor. When these pass over ground signal equipment,
There is a problem in that the signal equipment malfunctions due to the magnetic flux generated from the wiring. This problem will be specifically explained.

In FIG. 1, three-phase alternating current with a high harmonic content flows through load lines 19-21 due to the switching operations of GTO thyristors 6-11. This current value is much larger than the signal current of the ground signal equipment described later, and relatively low-order harmonics of the switching frequency of the GTO thyristor tend to match the signal frequency. FIG. 2 shows an example of the outfitted state in a perspective view from above the floor. An inverter device 4 and other control equipment (not shown) are arranged under the floor of the vehicle body 23 between the bogies 22, only one of which is shown. Further, the induction motor 18 is attached to the truck 22. Therefore, as is clear from the figure, the load lines 19 to 21 through which the three-phase alternating current with a high harmonic content flows are wired between the inverter device 4 and the induction motor 18, and are further wired within 1 (m) from the ground. Therefore, the magnetic flux reaching the ground is extremely strong. By the way, signal equipment on electric train tracks is generally configured as follows. A closed section is provided that is insulated from other sections in terms of alternating current, a signal current of a constant frequency is passed through the rail from one end, and a power receiver is installed at the other end or at an intermediate point. If the signal current is received at the power receiving end where the power receiver is installed, it is assumed that no train will enter the blocked section. If a train enters the system and the axle causes a short circuit between the transmitting end and the receiving end, there will be no receiving input at the receiving end, and the approach of the train will be detected based on the lack of receiving input.

There are two types of power receivers: non-modulation type and modulation type. The non-modulation method detects a signal current at a constant frequency and converts it into a DC voltage. It operates when the frequency of the noise input and the receiving frequency match, and the receiving sensitivity is generally high, making it relatively weak against noise.

The modulation method involves modulating a carrier wave with a code wave of a lower frequency, transmitting the signal in two stages in the order of carrier frequency and code wave frequency, and then detecting and converting it to a direct wave voltage. Strong to the point. The signal frequency for both unmodulated and modulated systems is generally 1 (K
Hz) to several tens (KHz), modulation code wave is 10 to 50 (Hz)
It is. Further, the signal current value is 10 to 100 (mA).

Figure 3 shows the configuration of the power receiver. In Fig. 3, 24 is the rail, 25 is the loop coil, i _S is the signal current, φ _S is the signal magnetic flux, R is the power receiver, e _O is the output voltage,
e _R is the receiving voltage. The operation is as follows. Magnetic flux φ _S generated by the signal current i _S flowing through the rail 24
is linked to the loop coil 25, and a power receiving voltage _eR is applied to the power receiver R. Power receiver R uses a modulation method.
Outputs DC from the receiving voltage _eR using a wave detector and detection circuit with a carrier wave frequency of 2.3KHz and a code wave frequency of 20Hz.
Obtain e _O and drive relay RL. Generally relay RL
The minimum operating voltage is approximately 5V, and the release voltage is approximately 2.5V. Considering the safety of ground signal equipment, the electromagnetic induction noise voltage e _O generated from the main circuit wiring of the inverter equipment to the power receiver must be suppressed to 1/2 or less of the release voltage of the relay RL, that is, 1.25V or less. There is.

As a method to reduce the amount of electromagnetic noise generated in trains that use semiconductor switching elements,
A commonly used method is to add electric wires with high reciprocating current, or to twist them together (for example, see Japanese Patent Publication No. 58-29681). However, in inverter-controlled trains, factors such as the current phases of the three load lines are different and the frequency changes continuously, so it is difficult to simply connect the load lines.
Alternatively, there is a problem in that the amount of electromagnetic noise generated cannot be significantly reduced even by twisting.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a train drive system that causes less interference with guidance to ground signal equipment.

[Summary of the invention]

In the present invention, as a result of experiments to determine how the electromagnetic induction noise voltage e _O to the ground-side power receiver changes by changing the twist pitch of the load line of a three-phase induction motor, we found that the twist pitch P of the load line changes. It was confirmed that the electromagnetic induction noise voltage _eO was minimized at each point on an even number of the length l of the receiver loop coil in the direction parallel to the rail, making it possible to reduce inductive disturbances. be. The experimental results are shown in FIG. 4, where the load current is 700 A and the maximum frequency is in the range of 0 to 100 Hz.

[Embodiments of the invention]

A schematic diagram of one embodiment of the invention is shown in FIG. In the figure, the part surrounded by the broken line is the load line 19 to 19 in Figure 2.
21 are twisted and wired at a pitch that is an even number of the length l of the loop coil. Also the 6th
The figure is an enlarged view of section A in FIG.

It is possible to further reduce electromagnetic induction noise by further inserting and wiring the above-mentioned load lines 19 to 21 into a duct made of a non-magnetic material with low electrical resistance, such as aluminum.

According to the present embodiment described above, it is economical because electromagnetic induction noise can be reduced without adding any special members. Also, wiring work is easy.

〔Effect of the invention〕

According to the present invention, it is possible to significantly reduce electromagnetic induction noise to ground signal equipment, so even on existing lines where highly sensitive signal equipment is installed, an inverter can be used that can safely operate without causing guidance interference. We can provide a train drive system equipped with this.

[Brief explanation of drawings]

Figure 1 is the main circuit configuration diagram of the inverter device, Figure 2
3 is a diagram showing an example of the underfloor equipment state, FIG. 3 is a diagram showing the configuration of a power receiver, FIG. 4 is a diagram showing an example of experimental results, FIG. 5 is a diagram showing an example of the present invention, 6
The figure shows an enlarged view of section A in FIG. 4... Inverter device, 18... Three-phase induction motor, 19, 20, 21... Load line, 24... Track rail, 25... Loop coil, l... Loop coil length, P... Load line twist pitch.

Claims (1)

[Claims] 1. Inverter device 4 and load lines 19, 20, 2
1 and a three-phase induction motor 18, the inverter device 4 is installed under the floor of the train and outputs three-phase alternating current with variable frequency and variable voltage, and load lines 19, 20 and 21 are the inverter device 4
The loop coil 25 of the ground signal equipment installed between the rails 24 is twisted together at a pitch that is an even number of the length of the loop coil 25 in the direction parallel to the rails, and is installed under the floor of the train. The phase induction motor 18 is a train drive device that is installed under the floor of the train and connected to load lines 19, 20, 21 to drive the train.