Strictly speaking, an electric motor is not just a motor, it’s a dual-purpose machine, because it serves not only as an efficient drive unit but also as a generator in deceleration phases. 

Unlike the combustion engine, an electric motor does not produce its power by means of pounding pistons but through rotation. Audi uses what is known as the asynchronous motor, which works without magnets or rare earths. The motor’s power electronics build up a three-phase rotating field in the stator’s copper windings. This induces a voltage in the rotor which in turn produces an electric current and therefore a magnetic field. The magnetic force is translated without a clutch to what is usually a single-speed gearbox and the drive wheels. This is possible on account of an electric motor’s foremost advantage: its enormous efficiency. 

A combustion engine has to rev up before it can produce torque, whereas an electric motor produces all of its trust as soon as you press down on the accelerator pedal.

An electric motor does not have to “get up to speed” before producing its propulsion. It produces its maximum torque from the word go. A combustion engine has to rev up before it can produce torque, whereas an electric motor produces all of its trust as soon as you press down on the accelerator pedal. Also, up to 95 percent of the energy you feed into it gets converted into usable power, whereas a combustion engine, depending on design, can only ever achieve an efficiency of between 35 and 45 percent. But the electric motor’s efficiency is not just a result of the motor itself, it presupposes perfectly matching power electronics which can control the electric motor’s complex processes. 

Electric motors have a number of other benefits. Because of the way they’re built, electric motors produce very little noise or vibration, making driving extremely comfortable. They have fewer wearing parts than combustion engines, which means they last longer and require less maintenance. Electric motors are also exemplary from an environmental point of view when driving: not only do they produce no emissions locally, they also reclaim energy during deceleration phases by becoming generators. Braking energy in most conventional vehicles is almost all converted into heat – therefore wasted – at the brakes, whereas in electric vehicles, energy can be transformed in the opposite direction. When accelerating, the electric motor is supplied with electrical energy with which it produces mechanical energy. When decelerating, the vehicle’s kinetic energy drives the electric motor mechanically, allowing it to reclaim electric energy which is fed into the vehicle’s batteries, where it can be used again later for powering the vehicle. This is known as recuperation. A new, fully electric brake booster can regulate the drive management system of an electric motor at deceleration of up to 3 m/s², meaning that almost all of the vehicle’s kinetic energy is fed back into the system when braking, then used for accelerating again. This is basically an entirely new form of braking, and turns every red light into something to be glad about.

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