Transportation in Tokyo and Its Surrounding Areas

2.1 Ground facilities

For traction, used in Tokyo and its environs is the direct current of 1, 500 volts. The facilities set up in this connec­tion are summarized below.

1). JNR-owned power generating facilities

Electricity used for train operation in Tokyo and environs is mostly supplied by JHR-owned power generating plants, comprised as at the end of March, 1967, of the Ojiya and the Senju Hydraulic Power Plants on the Shinano River system, producing 195, 000 kilowatts, and the Kawasaki Thermal Power Plant in Kanagawa Prefecture, producing 210, 000 kilowatts, totaling 405, 000 kilowatts (рис. 15).

2). Transforming facilities for traction on commuting sections

The total extended length of the commuting sections (рис. 16) is about 370 km, served by 53 substations in all. Their total capacity is about 500, 000 kilowatts, including that supplied for the traction of long-distance passengers trains and freight trains. Their maximum load per hour is about 250, 000 kilowatts.

In order to supply power sufficiently for the fabulous commuter traffic mentioned before, the substations are spaced at about 6.9 km, the shortest span being 1.2 km. These are remote controlled from 14 control centers. There is a plan on foot to set up 18 additional substations and to turn all, including the existing ones, into unmanned substations for centralized control from 9 stations.

3). Catenary System

Now that current load has increased, the conventional simple catenary is being turned into the double simple catenary. The work is expected to be completed before long.

4). Others

As more current is used for train operation, it has now become difficult to distinguish between fault current and traction current. To overcome the difficulty, JNR has a selective circuit breaker developed to distinguish fault current and, at the same, to enhance safety by using a system of linked breakers in combination. Also adopted are ATS (automatic train stop) and wireless for trains to prevent accidents in its attempt to ensure greater safety.

2.2 Rolling stock equipment

As a great number of passengers have to be carried speedily in a large city

and its vicinity, the rolling stock for commuter service and suburban service must be such as to have a high acceleration and deceleration power.

To meet such requirements, JNR has 101-series electric railcars developed. The outstanding characteristics of this type cars are:

(1) Two powered cars as a unit have eight traction motors in all, operated by one pilot controller.

(2) For high deceleration, the dynamic brake is used together with an automatic air brake in combination with an electromagnetic straight air brake.

(3) The rating of the traction motor is: terminal voltage, 375 V, 300 amperes, 2, 450 rpm at the maximum weak field of 40%, output, 100 kw; a high-speed motor, indeed. The driving system is of the parallel cardan device with hollow shaft and a large gear ratio.

(4) To facilitate passengers boarding and alighting, the car has four bi-parting doors on one side, each with a width extended to 1, 300 mm.

This 101-series electric railcars are operated at present in Tokyo and its vicinity in a 6M 4T consist of 10 cars (6 motive cars and 4 trailers) (рис. 17).

Lately, a 103-series type of higher quality which is more economical to operate, has been developed. Though basically the same as the 101-series type, it has a traction motor of 110 kW, and the cars are operated in 8-car consist, M: T = 1: 1 as the standard. The acceleration and deceleration rates would gener­ally vary depending on the load. As this would give rise to a problem in shortening the train intervals, the 103 series car compensating device equipped produce a given rate of acceleration and deceleration, regardless of the load.

Also for suburban service, JNR has a 1ll-series electric railcar developed. Produced to be used during commuting hours as well, it has three bi-parting doors. Its compartment is of semi-cross seats.

Its main electric equipment and power transmission system are the same as those of the 101-series car, though its gear ratio is made 1: 482, against the 101-series 1: 560, for operation at higher speeds. The standard is 6M 5T but with a 2M 2T supple­mentary consist, the train of these cars are operated in a long consist of 8M 7T (табл. 7).

As is clear in the table, over 12 cars are put into operation on the average for each route km in the commuting sections of Tokyo and its vicinity. On the Yamate line, the number is as many as 16 cars per km. This goes to show how efficiently the electric railcars in Tokyo and its vicinity are operated.

Таблица 7

2.3 Train operation

As explained before, with the improvement in the acceleration power of commuter type electric railcars, it has become possible to operate trains at shorter intervals. As a matter of fact, the trains on the Yamate line are operated at the minimum headway of 2 minutes. However, as it is impossible to run trains at such a headway, JNR has its block section for commuter traffic con­siderably shortened.

When only electric railcar trains are run, as on the Yamate line, a short length of block section presents no problem at all. However, when ordinary trains are run as well, as on the Chuo line (рис. 16), a short block section won't do because of the braking distance required of such trains. So, a device for detecting kinds of rolling stock is installed in such a way as to let the electric railcar train alone enjoy the advantage of a short block section.

2.4 Commuter service improvement projects under the Third Long-term Plan of JNR

The transport demand in urbanized areas is growing so rapidly, JNR is now confronted with the urgent problem of how to deal with the commuter traffic. Under the First and Second Long-term Plans, JNR invested some 72, 500 million yen in its attempts to improve its track facilities, station facilities and electric installations, as well as to increase the number of rolling stock for longer train operation, so as to reduce the train headway (табл. 8).

Таблица 8

Notwithstanding, however, the influx of population into urban areas has continued with greater intensity to worsen the urban traffic. The congestion has so worsened that no plan for transport capacity boosting centering around rolling stock alone suffices. The time has come for a drastic step — construction of additional tracks as the basic requirement for service im­provement.

JNR, therefore, came up with a Third Long-term Plan, aiming at the improvement of commuter service as a target, earmarking 520, 000 million yen (400, 000 million yen for. ground facilities improvement included) for investment to turn all the tracks in Tokyo and its vicinity, for commuter traffic as well as others, into quadruple and triple tracks.

This drastic step will surely expand JNR's transport ca­pacity to an enormous extent. However, when we consider the transport demand that is expected to soar in the future, this will, on its completion in 1971, reduce the present congestion rate of 300% to only 240% per rush hour.

The main problems in the way of improving urban traffic are —,

(1) The utilization efficiency of rolling stock and electricity is deplorably low, because of the high rate of transport demand concentration, requiring the massive commuter service to be performed during only three or four hours a day.

(2) The high cost of land requisitioning for additional tracks in urban areas.

These two problems must by all means be tackled and overcome as part of a city administration policy in order to deal most effectively with urban traffic.