Why electric cars they are not equipped with manual gearbox like those with a traditional internal combustion engine? Zero-emission motors are completely different from thermal motors, and so is their transmission: let’s find out what the differences are.
The news of gear shifting
Many motorists express their opposition to driving electric cars primarily for one reason: the electric motor does not have a gearbox, just press the accelerator to make the car drive faster. However, the myth of this seemingly automated operation must be dispelled: in reality, even electric cars have a gearbox, it is only a matter of single stage gearbox.
And to be more precise, there is also a famous exception to this rule represented by the Porsche Taycan, which has at least two gears. Who knows if there will ever be a day when even electric cars will have a 6- or 7-speed automatic transmission. In the meantime, let us examine the question step by step.
Electric cars have a different engine – what are the characteristics
As is known, on traditional internal combustion engines, the power and torque are expressed by the engine does not are constant: these variables increase with engine speed up to a peak, to then stabilize and eventually go down a bit. This just described is the reason why turbo engines were invented: to have more torque from low revs.
But when the car stops and has to move, it must of course have maximum pressure to move and move the entire weight of the vehicle. It is here exchange, which multiplies or de-multiplies the engine speed based on the speed you want the car to acquire. For example, a classic 5-speed manual gearbox reduces engine speeds when in first, second and third gears and multiplies them by fourth and fifth. In an electric motor this whole process of shifting gears it is not necessarybecause the pair is expressed practically immediately And does not there is no gap at low revs to be filled via a gearbox.
For electric cars do not have a gearbox, but only one gear
Below we will try to explain this peculiarity that only machines with 100% electric motors have. Take, for example, the modification of one of the newest electric cars, the Volkswagen ID.3 which has already been on the market for a few months and is enjoying good sales success. ID.3 her and gearbox single speed.
In its version top of the rowor the Pro Sthat Volkswagen ID.3 it has one 150 kW power (about 204 horses) And 310 Nm maximum torque. The latter is Available immediately and is very slightly higher than 2.0 TDI four-cylinder turbodiesel produced by the same Volkswagen manufacturer. In the latter cars, the torque force is expressed between 1,500 and 2,500 engine revolutions. Note in this regard for further information the driving torque That’s the moment mechanic of system of forces exerted by a motor on a broadcast. It varies as the motor speed changes with a tendency depending on the motor type and its power supply and has a maximum value in accordance with a given speed.
It is also specified that in order to achieve maximum power of 150 kWthe electric motor in ID.3 must rotate high speed: in this regard, just think that maximum speed of 160 kilometers per hour the engine runs at 16,000 rpm. The gearbox, for this, uses a gear ratio of 10: 1.
In this way, of course, two specific purposes are achieved at the same time: at low revs there will already be torque, at high speeds a more than sufficient speed is achieved instead. A longer gearbox, though always single-speed, would allow a higher maximum speed, but at the expense of low-speed gears, and the latter, as you know, guarantees a low fuel consumption in most of the driving modes and trips made.
Porsche two-speed gearbox, the first with a 15: 1 ratio and the second with an 8: 1 ratio
From the above, it is therefore clear that electric cars have gearbox for a single gear because they do not need to increase the speed through the manual gearbox mechanism, a mechanism which, for example, internal combustion engines have. This is because, as mentioned, the transmission torque is instantaneous and simply by pressing the accelerator with the foot, the car increases the speed without creating gaps in speed.
At this point, however, the question arises: why the group Volkswagen did you choose to equip the ID series with a single-speed gearbox, while for the Porsche Taycan you preferred a two-speed gearbox? In this context, the question arises: which exchange is better? In fact, the answer is no: in the field of ID, the two-speed gearbox would not make sense, while a Taycan with only one gear would not be able to express all its power.
On it Sports electric Porschein fact, the horsepower rises to over 700 and the torque reaches 1,050 Nm. On such a car, the single-speed gearbox could have been transformed into the classic “blanket for short”: to make all that torque transferable to the ground (which, let us remember, is available almost immediately) the maximum speed should have been limited too much.
This is not possible in a sports car. Here then is the reason for the second gear, which automatically goes in after 100 kilometers per hour and allows a greater extension and a maximum speed of 260 per hour. On it Porsche TaycanTo be precise, the first gear has a ratio of 15: 1 and the second gear of 8: 1.
There sustainable mobility represents the future of the automotive world, and certainly in the years to come, the classic polluting internal combustion engine will be completely and utterly replaced by electric and hybrid cars. In this way, fewer pollutants will be dispersed into the atmosphere, and all this will bring undeniable benefits to both health and nature in accordance with European and international rules.
Last modified: December 15, 2021