Transmission diesel-électrique
A diesel–electric transmission, or diesel–electric powertrain, is a transmission system for vehicles powered by diesel engines in road, rail, and marine transport. Diesel–electric transmission is based on petrol–electric transmission, a transmission system used for petrol engines. Diesel–electric transmission is used on railways by diesel–electric locomotives and diesel–electric multiple units, as electric motors are able to supply full torque at 0 RPM. Diesel–electric systems are also used in marine transport, including submarines, and on some land vehicles. The defining characteristic of diesel–electric transmission is that it avoids the need for a gearbox, by converting the mechanical force of the diesel engine into electrical energy (through an alternator), and using the electrical energy to drive traction motors, which propel the vehicle mechanically. The traction motors may be powered directly or via rechargeable batteries, making the vehicle a type of hybrid electric vehicle. This method of transmission is sometimes termed electric transmission, as it is identical to petrol-electric transmission, which is used on vehicles powered by petrol engines, and to turbine-electric transmission, which is used for gas turbines. Submarine#Diesel–electric transmissionSubmarine propulsion – diesel–electric transmission Diesel-electric transmissions are a type of Continuously variable transmission. The absence of a gearbox offers several advantages, as it removes the need for gear changes, thus eliminating the unevenness of acceleration caused by the disengagement of a clutch. Disadvantages of a diesel electric transmission are the potential complexity, cost, and increased losses due to energy conversion. Ship#Propulsion systems and electric boat The first diesel motorship was also the first diesel–electric ship, the Russian tanker Vandal from Branobel, which was launched in 1903. Steam turbine–electric propulsion has been in use since the 1920s (s), using diesel–electric powerplants in surface ships has increased lately.
