SBB Re 460 (Lok-2000)
Re 460 series is a modern four-axle multi-purpose electric locomotive operated by the Swiss Federal Railway (SBB CFF FFS) company in Switzerland. We can see these locomotives serving daily in the passenger trains.
Manufacturers of these locomotives were ABB (electric equipment) and SLM (mechanical part). The timeless design originates from Pininfarina studio. The locomotive is suitable for passenger trains as well as cargo trains. However, due to its ability to reach operation speed of 200 km/h (design speed 230 km/h) all the locomotives nowadays are utilized in passenger transport.
The Re 460 locomotives are popularly known under the name “Lok-2000” since they were introduced as part of Rail 2000 project, a large project to modernize the Swiss railway system and increase its capacity.
History
Already in 1970s the Swiss Federal Railways evaluated suitable forms of future high-speed passenger transport. The project became later known as Rail 2000. The maximum speed was defined as 200 km/h. In 1989 the SBB announced a tender for large series of locomotives in order to increase the capacity. The consortium SLM/ABB could secure the order although only a design of the locomotive was available.
Power supply
SBB 460 series uses the supply system 15 kV, 16.7 Hz that is common in Switzerland, Austria and Germany. The locomotives for Finland and Hong Kong (see below) are supplied from 25 kV, 50 Hz.
Traction motor
The muscles of the Lok 2000 are converter-fed asynchronous motors rated 4 x 1’200 kW.
Power electronics and technical solution
The heart of the locomotive are GTO (Gate Turn-Off) thyristors. The power semiconductors and heat sinks are arranged into power stacks (phase building blocks). Six such stacks create a 4-quadrant converter. The whole power electronics is mounted in an aluminum tank. The power components are oil cooled. The thermal capacity of the oil cooler is so high that natural cooling is sufficient when operating in and around the station (advantage of low noise).
Attractive look
The 460 series features attractive design that looks very modern still after almost 30 years of operation. The designer of the locomotive is famous Pininfarina.
Special design of the roof
The roof of the lok 2000 differs from any other conventional locomotive. It is a monolithic welded construction made from aluminum forming a vault-like hollow space. This space houses the main circuit breaker with integrated earthing switch, primary voltage transformer and the high voltage line between both pantographs and protects the equipment against moisture and dirt. The design of the roof significantly improves the aerodynamic properties by reducing air resistance and generated noise. The hollow space also serves as calming room for cooling air of traction motors. The roof also allows to remove key components from the machine room without need for disassembling.
Outline drawing
The outline of the Lok 2000 is depicted in Figure 2.
SBB 460 and BLS 465
Two major customers for the new locomotives were the Swiss Federal Railways (SBB CFF FFS) as series 460 and Bern-Lötschberg-Simplon (BLS) railways as series 465. Key data of both variants are summarized below:
SBB 460
Maximum power: 6’100 kW
Maximum speed: 230 km/h
Pulling force: 300 kN
Braking force: 240 kN
Weight: 84 t
Drive control: Bogie
DC voltage: 3’500 V
Traction converter: 3-level
Inverters per bogie: One (1)
Number of GTO thyristors: 60
Number of power diodes: 88
Pole number of traction motor: 4
Max. line-to-line motor voltage: ~ 2’600 V
Max. frequency of traction motor: 147 Hz
Delivery: 1993-1996
BLS 465
Maximum power: 7’000 kW
Pulling force: 320 kN
Weight: 84 t
Drive control: Individual axis
DC voltage: 2’800 V
Traction converter: 2-level
Inverters per bogie: Two (2)
Number of GTO thyristors: 52
Number of power diodes: 56
Pole number of traction motor: 6
Max. line-to-line motor voltage: ~ 2’200 V
Max. frequency of traction motor: 213 Hz
Delivery: 1994-1997
Export success of Swiss railway industry
The locomotives abbreviated from Lok 2000 became a successful export article. With specific modifications the locomotives were delivered for railway companies in Norway, Finland and Hong Kong.
– Norway: EI 18
Norwegian State’s Railways (NSB) ordered 22 units of this type. They were designated as EI 18 series.
– Finland: SR 2
46 locomotives of type Lok 2000 were delivered for Finnish Railways (VR). Those are in broad gauge execution.
– Hong Kong
2 locomotives were even supplied to far Hong Kong.
Retrofit program of Re 460
The Lok 2000 is serving reliably in daily operation across Switzerland since early 1990s. As the power electronics evolved over the years there is an opportunity for a retrofit. ABB, the manufacturer of the electrical part of original Lok 2000, is supporting a wide retrofit program that replaces original GTO based power converters with IGBT based state-of-the-art traction converter (ABB Boardline). The retrofitted locomotives improve their overall efficiency and extend their lifetime for next decades.
ABB will gradually modernize the entire fleet of 460 locomotives. Each of those locomotives traveled on average 5.5 million kilometers.
References
[1] Swiss Federal Railways SBB-CFF-FFS, https://www.sbb.ch/en/home.html
[2] ABB Traction converters, https://new.abb.com/power-converters-inverters/traction-converters
