Linimo hovers close to take-off
INTRO: Test running has started on a 9 km light metro being built to serve next year's World Expo and a research and development zone to the east of Nagoya
'IN HARMONY with the environment' proclaims the yellow flag, fluttering high above Nagoya's main station. It is advertising the 2005 World Expo, which is being hosted by Aichi Prefecture in a 180ha regional park that has been temporarily transformed into one of Japan's biggest building sites.
Striding past the venue is a high concrete viaduct, with small three-car trainsets gliding silently by. This is Linimo, the world's first commercial application of HSST maglev technology. The line is scheduled to open at the beginning of March 2005, three weeks before the Expo starts on March 25. Test running is now getting into full swing as the builders put the finishing touches to the nine stations along the route.
Aichi Prefecture is keen to promote itself as a centre for research and development. Several universities, an agricultural research centre and the Toyota R&D laboratories are clustered along the corridor running east-west past the Expo site. This area is poorly served by public transport at present, there being a 20 km gap between the parallel Seto and Toyota lines of the local Nagoya Railway Company, Meitetsu.
To serve the embryonic Aichi Academic Research & Development Zone, the prefecture decided in principle about 15 years ago to build some form of light metro link feeding into the metro terminus at Fujigaoka. The impending Expo set a firm deadline, and in 2000 the third-sector company Aichi Kosoku Kotsu (Aichi Rapid Transit Co Ltd) was formed to build and operate the line.
AKK is a public-private partnership, 51·8% owned by six regional governments including Aichi Prefecture, Nagoya City and four local municipalities. The other 48·2% is held by private-sector companies, of which the largest shareholder is Meitetsu.
The line is authorised under Japan's tramway legislation, rather than metro or heavy rail rules. Reflecting its pioneering role, the central government is helping to fund the civil works along with Aichi Prefecture and Nagoya City. This includes the viaduct and stations, which are being built in parallel with road improvements to serve the Expo site. AKK is responsible for the E&M works, including the track, vehicle and control systems, together with the operation of the finished line. Total investment is ´103bn, of which the infrastructure accounts for ´67bn and the E&M package ´36bn.
At the time the project was authorised, the choice of technology was still open, with a monorail, AGT rubber-tyred peoplemover or maglev under consideration. Aichi Prefecture organised a system evaluation and selection comm-ittee with third-party members, and based on its recommendation decided to adopt HSST maglev technology.
Acting as technical consultant to AKK is Chubu HSST Development Corp, the current licensee of the technology which is promoting HSST along with trading company Itochu. The concept had been originally promoted by Japan Air Lines, who bought the patent rights for the levitation magnet and rail arrangement from Krauss-Maffei back in the 1970s and established a test track at Kawasaki, near Tokyo. In 1985 the work was spun off to JAL subsidiary HSST Corp, which subsequently built and operated a number of short demonstration lines at expos and fairs around the world.
Four years later, it was decided to build a permanent test track in Nagoya for further research, and to work towards Ministry of Transport approval for revenue operation. Chubu HSST Development Corp was formed to fund this stage of the process, with a registered share capital of ´30bn. Meitetsu is the largest shareholder in the new company, together with Aichi Prefecture and JAL. Chubu HSST is currently in discussions with Alstom over a possible joint technical development agreement, which may lead to a third generation of the HSST concept.
Along the route
Officially known as the Tobu Kyuryo Line, the light metro starts from a stub terminal in tunnel beneath the elevated Fujigaoka terminus of Nagoya's Higashiyama metro line. The first 1·4 km runs in a bored tunnel, dug with a 'binoculars' twin-bore TBM, as far as the first station at Hanamizuki-doori. Rising onto an elevated guideway, the route takes a long dog-leg above a side street to reach the Nagoya - Chikaraishi prefectural highway at Irigaike-kouen station.
The remainder of the line parallels the main highway on the south side, past the Expo site, to terminate at an interchange with the Aichi Ring Railway at Bampaku-Yakusa. There are four other intermediate stations.
Steepest gradient on the route is 6%, where the line passes over the hills of Aichi Youth Park, 120m above the Fujigaoka terminus. Sharpest curve radius is 75m at Hanamizuki. The depot and AKK offices are located on a 3·5ha site immediately east of the park. Here there is a two-road inspection and maintenance shed, a washing track and three stabling roads, linked to the running line by a sharply-curved single-track spur which leads up to a central reversing platform at the Expo station.
Apart from Hanamizuki, which has two side platforms, and Bampaku-Kaijou which has three tracks and two island platforms, all the other stations have a single central island, reached from ground level via an intermediate mezzanine concourse. Stairs, escalators and lifts are provided to ensure full disabled accessibility.
Platform screen doors are fitted to all stations, because the trains will be fully automatic. Only three stations will have full-time staff; the remainder will be monitored by CCTV and roving attendants. To cope with the additional crowds during the Expo, Bampaku-Kaijou station is being provided with temporary side platforms and extra stairways.
A ground-breaking ceremony for the line was held in February 2002, and the elevated section is now complete. Test running began on June 28 this year, and so far six of the nine trains have been delivered for commissioning tests. Work on the tunnel is due to be finished next month, allowing test running to be extended through to Fujigaoka. AKK General Manager Shunzou Ishimoto expects the line to be ready for formal inspection by the Ministry of Land, Infrastructure & Transport at the start of February 2005, allowing the operation of a full shadow service for at least a month before the planned opening at the beginning of March.
HSST technology matures
Linimo will be operated by a fleet of nine three-car trains, each able to carry 104 seated and 140 standing passengers. There is also one bank of folding seats in each end car, giving provision for two wheelchairs per train. Large windows are provided which Ishimoto emphasises will give panoramic views of the area from the elevated guideway.
Excluding the Expo traffic, forecast demand for the Tobu Kyuryo Line is 31000 passengers per day in 2005, rising to 33000 by 2015 and 34000 in 2025. Design capacity of Linimo has therefore been set at 4000 passengers/h in each direction, which will require six trains in service and two spares. Trains will run at 6min headways during peak times and every 10min off-peak, with AKK expecting to operate 110 trips per day in each direction.
According to Ishimoto, the ninth train is being funded by the Aichi Expo Association to provide additional capacity during the six months of the fair, but he is not sure whether it will be retained after the end of next year.
The aluminium-bodied trains are being built in Toyokawa by Nippon Sharyo. Each set is 43·3m long and 2600mm wide. Tare weight is 17·3 tonnes per car, or 52 tonnes per train. In place of conventional bogies, the cars ride on what Chubu HSST calls 'module bogies', which have four suspension magnets at the corners and two linear motors arranged along the sides. Conventional electromagnets are used for levitation, unlike the superconducting magnets used under JR-Central's high speed test trains at Yamanashi. Each car is carried on five module bogies, with airbag secondary suspensions.
The modules are being assembled by JAMCO, a supplier of modular fittings for the aircraft industry, using magnets and motors supplied by electrical manufacturers. Each car is carried on five modules, giving a total of 60 magnets and 30 motors per trainset. The motors are each rated at 40 kW and the electromagnets need 800W per tonne of vehicle weight, giving a total power requirement of around 1250 kW.
Power to the train is supplied at 1·5 kV DC from third and fourth rails mounted on either side of the 1200mm high track support structure. The levitation magnets are slung beneath the running rails, and lift the vehicle by attracting the steel rails from below. This lifts the car off its 'landing skids' to give a gap of around 8mm. The aluminium reaction plates for the linear motors are laid along the top surface of the rail, with a gap of about 15mm from the stators. A central 'signalling rail' is laid along the middle of the track to provide an inductive link for the train control system.
Each module is also provided with hydraulic clasp brakes which clamp onto the rails to hold the train still during station stops. Service braking will be electro-dynamic, and a parking brake facility is provided by the landing strips. An automated inspection shed at the depot scans the brake pads and collector shoes whenever a train enters or leaves service, to ensure that all wearing parts are within operational tolerances.
Although Linimo is designed to operate fully automatically, driving controls are fitted in a locked cabinet at each end of each train. Emergency evacuation doors are fitted at each end, with folding steps leading down to the middle of the track. A separate portable evacuation ladder will allow passengers to climb down from the elevated track to a central walkway between the running lines. With the stations spaced at an average of 1 km apart, there are no intermediate stairways for emergency access or evacuation.
The control centre has two main workstations: one to oversee the signalling and train control, and the other the power supply network and the lineside CCTV. Video surveillance covers all the station areas, but is not fitted to the cars, which have two push-button intercom points per vehicle allowing passengers to contact the controllers.
With the support modules wrapping around the track structure, switching of trains between tracks requires the use of flexible rail sections rather than fixed turnouts. Each point comprises two short sections and one longer one which can traverse laterally in a trapezoidal movement to create a gentle curve. There are scissors crossovers at each end of the main line, plus the central loop track at Bampaku-Kaijou station which gives access to the depot. Within the depot area, five switches are needed to link the various sidings and running tracks.
CAPTION: Soaring above the prefectural highway, a three-car train passes the Toyota Automobile Museum near Geidai-doori station during a trial run in July
CAPTION: AKK Senior Managing Director Shunzou Ishimoto (left), General Manager,Administration &Public Relations, Masashi Makino (centre) and Chubo HSST Senior Engineer Junro Kato (right) sample a short test ride around the Linimo depot on July 30
CAPTION: ABOVE: The main control centre features a back-projected display of the track layout and large screens for CCTV monitoring
ABOVERIGHT: The Linimo depot has three external stabling roads and a washing track arranged either side of the entrance road; the maintenance shed has one covered track for maintenance and another for inspection
CENTRE: The small shed over the depot headshunt encloses the automated equipment to inspect wearing parts under the vehicles
CAPTION: BELOWLEFT: Close-up of a support module, showing the levitation magnets at each corner, the longitudinal linear induction motor and reaction plate mounted above the rail and the hydraulic clasp brake (centre)
BELOW:Power is supplied at 1·5 kVDC by positive and negative rails mounted on either side of the elevated track structure
CAPTION: East of Kouen-Nani station, Linimo requires 6% gradients to climb up and over the hills surrounding the Expo site at Aichi Youth Park