Electric locomotive

In Europe and elsewhere, railway networks are considered part of the national transport infrastructure, just like roads, highways and waterways, so are often financed by the state.

The seven-ton vehicle had two direct-drive reluctance motors, with fixed electromagnets acting on iron bars attached to a wooden cylinder on each axle, and simple commutators.

The first electrically worked underground line was the City and South London Railway, prompted by a clause in its enabling act prohibiting the use of steam power.

Parallel tracks on the Pennsylvania Railroad had shown that coal smoke from steam locomotives would be a major operating issue and a public nuisance.

A collision in the Park Avenue tunnel in 1902 led the New York State legislature to outlaw the use of smoke-generating locomotives south of the Harlem River after 1 July 1908.

[11] Diesel shared some of the electric locomotive's advantages over steam and the cost of building and maintaining the power supply infrastructure, which discouraged new installations, brought on the elimination of most main-line electrification outside the Northeast.

In 1891, Brown had demonstrated long-distance power transmission for the International Electrotechnical Exhibition, using three-phase AC, between a hydro–electric plant at Lauffen am Neckar and the expo site at Frankfurt am Main West, a distance of 280 km.

The first implementation of industrial frequency single-phase AC supply for locomotives came from Oerlikon in 1901, using the designs of Hans Behn-Eschenburg and Emil Huber-Stockar; installation on the Seebach-Wettingen line of the Swiss Federal Railways was completed in 1904.

[27] In Europe, electrification projects initially focused on mountainous regions for several reasons: coal supplies were difficult, hydroelectric power was readily available, and electric locomotives gave more traction on steeper lines.

After trials, the company decided that the performance of AC locomotives was sufficiently developed to allow all its future installations, regardless of terrain, to be of this standard, with its associated cheaper and more efficient infrastructure.

[28] The SNCF decision, ignoring as it did the 2,000 miles (3,200 km) of high-voltage DC already installed on French routes, was influential in the standard selected for other countries in Europe.

Similar programs were undertaken in Italy, Germany and Spain; in the United States the only new mainline service was an extension of electrification over the Northeast Corridor from New Haven, Connecticut, to Boston, Massachusetts, though new electric light rail systems continued to be built.

On 2 September 2006, a standard production Siemens electric locomotive of the Eurosprinter type ES64-U4 (ÖBB Class 1216) achieved 357 km/h (222 mph), the record for a locomotive-hauled train, on the new line between Ingolstadt and Nuremberg.

[29] This locomotive is now employed largely unmodified by ÖBB to haul their Railjet which is however limited to a top speed of 230 km/h due to economic and infrastructure concerns.

DC locomotives typically run at relatively low voltage (600 to 3,000 volts); the equipment is therefore relatively massive because the currents involved are large in order to transmit sufficient power.

This system is particularly advantageous in mountainous operations, as descending locomotives can produce a large portion of the power required for ascending trains.

Railways generally tend to prefer overhead lines, often called "catenaries" after the support system used to hold the wire parallel to the ground.

It allows for smaller tunnels and lower clearance under bridges, and has advantages for intensive traffic that it is a very sturdy system, not sensitive to snapping overhead wires.

During the initial development of railroad electrical propulsion, a number of drive systems were devised to couple the output of the traction motors to the wheels.

The jackshaft drive was abandoned for all but the smallest units when smaller and lighter motors were developed, Several other systems were devised as the electric locomotive matured.

Again, as traction motors continued to shrink in size and weight, quill drives gradually fell out of favor in low-speed freight locomotives.

The other side of the housing has a tongue-shaped protuberance that engages a matching slot in the truck (bogie) bolster, its purpose being to act as a torque reaction device, as well as support.

Battery locomotives are preferred for mine railways where gas could be ignited by trolley-powered units arcing at the collection shoes, or where excessive electrical resistance could develop in the supply or return circuits, especially due to poor contact at rail joints, and allow dangerous current leakage into the ground.

[41] However, with the conversion of the Mount Royal Tunnel into the mainline of the Réseau express métropolitain light metro system and the permanent truncation of the Mascouche line to Ahuntsic station starting in January 2020, the locomotives are run exclusively in diesel mode.

[42] Similar to the US the flexibility of diesel locomotives and the relatively low cost of their infrastructure has led them to prevail except where legal or operational constraints dictate the use of electricity.

[43] Electric locomotives are used for passenger trains on Amtrak's Northeast Corridor between Washington, DC, and Boston, with a branch to Harrisburg, Pennsylvania, and on some commuter rail lines.

In North America, the flexibility of diesel locomotives and the relatively low cost of their infrastructure have led them to prevail except where legal or operational constraints dictate the use of electricity.

Amtrak and New Jersey Transit's New York corridor use electric locomotives, currently ALP-46s, due to the prohibition on diesel operation in Penn Station and the Hudson and East River Tunnels leading to it.

[47] Japan has come close to complete electrification largely due to the relatively short distances and mountainous terrain, which make electric service a particularly economical investment.

[50] Queensland Rail implemented electrification in the 1980s and utilises the more recent 25 kV AC technology with around 1,000 km of the narrow gauge network now electrified.