Maglev gives Nagoya a lift: opening of a maglev metro line in Nagoya, Japan, next year brings into service a technology that began to be developed in Japan more than 30 years ago

International Railway Journal, June, 2004

NAGOYA, Japan's fourth largest city, has Japan Air Lines (JAL) largely to thank for the maglev metro that opens in the go-ahead city in March 2005 (IRJ May page 8). It was JAI's dream of providing fast access to Japanese airports that launched a project, in conjunction with Sumitomo, to develop a new transport system called High Speed Surface Transport (HSST) in the early 1970s. That dream was never realised, but work continued on other applications.

Development work was transferred to Chubu HSST Development towards the end of 1998 and the following year the government approved an 8.9km, double-track maglev line, known as Linimo, with nine stations between Fujigaoka. the eastern terminal of Nagoya Metro's east-west Higashiyami Line, and Banpaku-Yakusa. It will serve the Aichi Exposition when it opens next year.

The Nagoya system is based on magnetic attraction like the German Transrapid but unlike, and simpler than, the high-speed superconducting maglev being developed by JR Central and Japan's Railway Technical Research Institute (RTRI). When the line opens, services will operate between 0500 and 2300 with 10 trains per hour (6 minute headways) during peak hours and six trains per hour at other times.

Construction work started in April 2002 and the first train was completed by Nippon Sharyo (with Sumitomo supplying the magnetic suspension equipment) in November the same year. The aluminum, three-car emus are 43.3m long, 2.6m wide and 3.45m high, with six doors on each side. Propulsion is by linear asynchronous induction motors controlled by variable voltage, variable frequency (VVVF) inverters. Each 100km/h, fully-automatic, driverless train has 104 seats and can accommodate a total of 244 passengers.

The mainly elevated track consists of two metal rails in the shape of an inverted U in which the attractive magnetic field is held to position the vehicle. A sensor measures the gap between the rail and the magnet cores while an electronic circuit amplifier is used to control the current to the electromagnets in order to keep the gap at about 8mm.

An aluminium reaction plate between the rails is, in effect, the rolled out rotor of the induction motor. Its reaction with the stator on the vehicle propels the vehicle. Each vehicle in a train has five magnetic modules consisting of direct current electromagnets for levitation and guidance, the linear motor, and a braking system. The switching system comprises steel girders in a three-segment horizontally rotating device.

The line is independent of other metro and commuter railways in Nagoya, which means that passengers will have to change at Fujigaoka or Banpaku-Yakusa on the Aichi Loop Railway to access the city centre. The construction cost is estimated at Yen 100.5 billion ($US 962.8 million), which includes Yen 60 billion for infrastructure and Yen 40.5 billion for rolling stock.

The lack of direct interconnection with other rail systems in Nagoya can he attributed to the preferential financial treatment given to monorails and other forms of guided transport in Japan, where, if they run over roads, they are treated as roads and therefore qualify for highway subsidies and grants.

The maglev has this status and so half of the construction costs are covered by government with the other half from local sources not being subject to any charges. Therefore, the Yen 60 billion infrastructure costs are charged as Yen 30 billion to the government, Yen 22-23 billion to Nagoya Prefecture, and Yen 7-8 billion to Nagoya City.

The cost of rolling stock, stations, and the train operations system are paid from capital (Yen 8.1 billion), borrowings without interest (Yen 12.2 billion), and borrowings with interest (Yen 20.2 billion). If the line had been constructed as a conventional railway, it could not have benefited from the preferential financial treatment and would therefore probably not have been built since the maglev line is calculated to cost 1.2 times more than a conventional line. But despite the financial implications, there were other technical problems with a conventional railway solution--the Nagoya metro is a standard-gauge system with third rail power collection, while the Aichi Loop Railway is narrow gauge with overhead power supply at 1.5kV. IRJ's regional editor in Japan, Mr Y Sato, believes the committee for technical standards made a reasonable choice with maglev taking the technical issues into account and the fact that maglev represents a modernist solution for the Aichi Expo while providing a new line for local inhabitants.

Another factor was that one of the main appeals of maglev is its quietness in operation due to the total lack of contact between the vehicles and the guidance system.

Aistom has shown interest in the Japanese application and envisages developing a second generation in conjunction with Itochu and Chubu HSST Development with whom it signed a cooperation agreement for worldwide sales in February 2002.

* The JR Central/RTRI high-speed maglev reached a milestone in April when JR Central announced that it had developed the world's highest-performance high-temperature superconducting (HTS) coil using bismuth high-temperature superconducting wires.