Gearbox - 'surplus' in electric vehicles

Most electric vehicles do not have a gearbox because the engine is attached directly to the wheel, the energy does not need to be transmitted through the intermediate part is a gearbox.

In internal combustion engines, the gearbox helps to change the torque transmitted to the wheels. But electric cars do not. Basically, electric vehicles only need a simple function button. When the button is activated, the car will immediately set up the simulation settings similar to the time when the driver uses an automatic transmission in a car using an internal combustion engine.

The button will allow the driver to select the usual feature. "Drive" lets the vehicle move forward, R when backing up, and N intermediate when stopping. Some other settings allow you to change the driving mode (such as fuel economy or sports), but in fact, it will not change the way the gearbox works, but will simply bring out the feelings. different sense only.

Start moving, maybe you will be surprised when the car accelerates and decelerates. There will be no shifting feeling here, just the car will soar like a linear line and return to a standstill without any jerk.

That's because electric cars don't need a gearbox to change speed like a petrol or diesel engine. They are simply forward or backward mode.

Nissan Leaf gear lever. Photo: Autocar

This makes them able to accelerate extremely well. The Tesla Model S, for example, reaches 100 km / h from its starting position in just 2.4 seconds, making it a family sedan faster than most supercars.

Extremely flexible electric motor. They produce power immediately after you click the accelerator and reach the engine speed up to 20,000 rpm, about four times that of a gasoline or diesel engine.

This means that electric cars are always efficient in terms of transmitting power because they do not need to change many gears to expand the optimal rpm range like conventional cars. Different gear ratios help the internal combustion engines adapt between traction and speed. That's why a petrol motorbike will easily reach 32 km / h at 1 gear, but it will be hard to get faster if the driver doesn't change the gear ratio to release the engine when reaching. to the maximum level of rotation in that level. And in logical order, the driver will move up to a higher gear level with a manual transmission, and in an automatic transmission, this is decided by the computer.

Because of the very wide rpm range, electric vehicles can reach maximum speed with only a number of engineers tuned to create the optimal balance between fast and slow travel. Most of them have the ability to accelerate faster than a conventional sports hatchback and easily overcome the speed limit of the highway, so there is no downside to the power.

This structure also helps to make electric cars less complicated to produce and maintain. An internal combustion engine system with a multi-level gearbox will cost the manufacturer more money, and drive up the price of the car.

However, this one-level gearbox rule may change in the future. In Formula E, some racing teams offer an option with a three-speed gearbox to optimize performance and energy efficiency, because of the capacity limit of the tournament.

For the streets, several concept car models were introduced with affordable two-speed gearboxes. This allows them to be paired with cheaper, smaller, lower-powered electric motors, as well as increase travel distances without compromising performance.

That guarantees a pure electric car future, but what happens to hybrids, which are a combination of an electric motor and an internal combustion engine? Most hybrid cars feel the same way as regular cars, but under the bonnet, the complex system works a bit differently.

For example, the BMW i8 uses a two-speed system, while Toyota hybrids use a CVT gearbox that is closer to the regular one, where a belt will move between the two cones to make sure. The engine speed is compatible for the purpose of promoting operation or saving fuel. The Mitsubishi Outlander PHEV has a "one-level" gearbox used in pure electric (EV) mode, connected directly to the wheels to accelerate, before it received power directly from a gasoline engine. The driver does not need to intervene during this process because the computer will automate everything.

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