JPS5838041B2 - Method for reducing electrical noise and noise due to pantograph disconnection - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for reducing electrical noise and noise generated in an AC electric railway when a pantograph current collector separates from a contact wire and a pantograph while an AC electric car is running.

Recently, the development of Shinkansen in Japan has been remarkable.
Based on the operational experience of the Tokaido and Sanyo Shinkansen lines, construction of the Tohoku and Joetsu Shinkansen lines is also underway.

While extending the Shinkansen will improve social welfare, it also causes pollution to residents along the line, including noise and radio interference.

Noise and radio interference caused by sparks during pantograph power collection are caused when the train speed is high (for example, 160 IcfrL/H).
It has been confirmed through experimental results that the occurrence is greatest under the conditions (above) and during coasting (a state in which power is supplied only to the auxiliary equipment without supplying power to the drive motor).

It is also a well-known fact that the amount of sparks generated due to pantograph disconnection is smaller when two pantographs are used in parallel than when one pantograph is used.

Currently, Shinkansen trains have one unit for every two cars, one pantograph, one main transformer for voltage conversion to lower the voltage, one main rectifier to convert DC, and eight DC series motors to connect two cars to the train. They are distributed and arranged to drive trains.

The secondary side electric circuits of adjacent pantographs are not connected inside the vehicle and are independent and independent electric circuits.

The feeding voltage on the Shinkansen is an extra high voltage of 25KV AC, and in order to connect adjacent pantographs on the car side, it is necessary to connect an equalizing line of the extra high voltage cable inside the car, and also to connect the electric car. If the line crosses a dead section at the junction of different power sources, a special high voltage switch is required to cut the equalizing line to prevent short circuits of different power sources.

However, it is technically very difficult to connect Shinkansen cars that experience strong vibrations using special high voltage cables, and it is also extremely difficult to install special high voltage switches under the narrow train floors. The pressure equalization line of the cable for use has not yet been implemented.

The present invention eliminates these difficulties and provides a method for reducing electrical noise and noise caused by pantograph disconnection by connecting the high voltage (approximately 2 KV) parts of the secondary side of each adjacent main transformer through a high voltage switch. It provides:

Embodiments of the present invention will be described in detail below with reference to FIGS. 1 to 3.

Figure 1 shows a side view of four cars (■, ■, ■, ■) of the 16-car Shinkansen train train, which is an AC electric vehicle. Pantographs P1 and P2 are installed every two cars. Electric power is supplied from the trolley wire T and the rail R via the wheels K by the electric voltage V (25 KV).

The distance l between the pantographs is 50 m.

Figure 2 is a main circuit wiring diagram showing the electric circuit of the Shinkansen train.

In other words, the main transformer T1 receives power from the pantograph PI (P2) and the wheels K, the contact wire T, and the rail R.
(T2), and the tap changer Tap. to the rectifier Rec. The main electric motor M for driving the train is driven through the .

Further, a tertiary winding is wound around the main transformer, and power is supplied to auxiliary equipment m such as a compressor.

Adjacent puncture graphs P1 and P2 are not electrically connected in the vehicle, and each has an independent electrical circuit.

Therefore, the generation of sparks due to the separation of the pantograph when the train is running increases because there is only one pantograph.

As a countermeasure for these, the special high voltage busbars on the vehicle side of pantographs P1 and P2 are connected to the equalizing wires W1 and W of the special high voltage cable.
If the pantographs P, , P2 are connected in parallel through the special high voltage switch S1 as shown in FIG.

However, this method is not practical because it is impossible to route special high voltage cables with high withstand voltage and install large special high voltage switches and the like inside the train.

Figure 3 shows an embodiment of the present invention, in which one terminal of the secondary windings of adjacent main transformers T1 and T2 in the train is opened and closed at the driver's seat using equalizing wires W3 and W4 of the high-voltage cable. Connection is made via a small and lightweight operable high-voltage switch S2, and the other terminals of the secondary windings of the main transformers T1 and T2 are electrically connected by an equalizing wire W5 of the high-voltage cable. It is something.

In this way, the secondary circuits of pantographs P1 and P2 will be connected through the leakage reactance of main transformers T1 and T2, and ultimately the equalization lines W1 and W2 of the extra high voltage cable shown in Figure 2 will be connected. As a result, the function is the same as when the secondary sides of pantographs P1 and P2 are connected, and since the voltage on the secondary side of the main transformer is relatively low at around 2000 VAC, high voltage cable routing and The high-voltage switch S2 is also small and lightweight, so it can be easily installed in a narrow vehicle.

Further, the current flowing between the main transformers due to disconnection is for a short time, and the capacity of the main transformers does not need to be increased by implementing the present invention.

The reason why a high voltage switch is installed in the equalizing line of a high voltage cable is that if the high voltage switch is not opened when passing through a different phase crossing section (usually an insulated section of about 8 m in length), the pantograph interval will change. (X - 50 m), voltages between different phases are short-circuited by the equalizing line of the high-voltage cable in the vehicle, causing a failure.

When the Shinkansen train passes through special places such as dead sections during transport, the speed must be less than 100 km/h,
Equalizing lines between pantographs are unnecessary.

Main transformer 2 between adjacent AC electric cars according to the present invention
By connecting the next windings in parallel, electrical noise and noise caused by pantograph disconnection can be reduced by wiring at relatively low voltage locations, making cable wiring easy and the essential high-voltage switch smaller. It is lightweight and very economical, and since it is a circuit in which multiple mechanically independent pantographs are connected in parallel, changes in electrical phenomena due to separation of the pantographs when the train is running are greatly reduced, and sparks are reduced. This makes it possible to significantly reduce electrical noise and noise.

[Brief explanation of the drawing]

Figure 1 is a side view of a Shinkansen train, and Figure 2 is a diagram showing the electrical circuit of a Shinkansen train. Circuit wiring diagram, Figure 3 shows the main transformer 2 according to the invention.
FIG. 3 is a main circuit wiring diagram in the case where the next windings are connected in parallel with equalizing wires. P1, P2... Pantograph, K...
Wheel, R...Rail, T...Trolley wire, T1, T2. ．． ．．・．．・Main transformer, Tap...
・Tap changer, ReC... Rectifier, S1...
...Special high voltage switch, S2...High voltage switch, W1, W2...Special high voltage cable equalizing wire, W3, W4, W5... - Equalizing line for high voltage cables.

Claims (1)

[Claims] 1. In an AC electric railway that has multiple pantographs in one train set and each train has a main transformer that transforms electric power for electric operation, one terminal of the secondary winding of the adjacent main transformer is The equalizing wire of the high voltage cable connects electrically through a high voltage switch that can be opened and closed from the driver's seat, and the other terminals of the secondary winding of the main transformer are electrically connected using the equalizing wire of the high voltage cable. A method for reducing electrical noise and noise due to pantograph disconnection, characterized by connecting to a pantograph.