The outer, stationary stator and the rotor housed within it make up the two main components of a three-phase asynchronous motor. The stator is a sheet package made up of thin electrical sheets that are magnetically conductive. The three three-phase current phases from the power electronics are connected within these copper wire coils. They produce a circumferential (spinning) magnetic field when a voltage is applied to them. The rotor is carried along with the excitatory rotating magnetic field of the stator with a low rotational speed difference, i.e. asynchronously, by the rotating field of the stator. The electric motor in the car functions as a traction motor if the rotor rotates more slowly than the rotating magnetic field. Alternatively, it can function as a generator, transforming kinetic energy into electrical energy. The asynchronous motors are extremely efficient because they do not experience any electrically induced drag losses when they are deenergized. Additionally, they have the ability to temporarily enhance their output, maximizing the car’s performance in boost mode. They offer additional benefits in addition to being incredibly light thanks to the aluminum rotor, including: They are exceptionally sturdy and require little upkeep. Additionally, the construction of the electric motors does not include the use of rare earth elements.
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Audi valvelift system (AVS)
Variable valve control is a technique that is used in the Audi valvelift system (AVS). Audi employs it for various purposes in several engines, although each engine’s operating principle is the same: The camshafts, which have cam profiles with various curves, are mounted with sleeves. The sleeves are moved axially a few millimeters by electromagnetically activated pins that enact into spiral-shaped grooves on their outer outlines. Depending on where the sleeve is, either the low cam or the high cam opens the valve.
The intake valves are affected by the AVS in the new 3.0 TFSI, the 2.9 TFSI, and the 2.0 TFSI with 140 kW (190 hp). According to engine load and speed, it modifies their lift and timing (opening duration) over two levels, which in turn regulates the volume of air that is admitted. The lift and opening durations are relatively brief in part-load operation. Throttle losses can be significantly eliminated if the throttle valve is left open. The AVS switches to a higher lift and delayed valve closing at higher loads. The size of the charge in the combustion chamber grows, and the engine can aspirate air freely for higher torque and power.
The AVS adjusts the lift of the exhaust valves in select gasoline engines with four cylinders and in the 2.5 TFSI with its five cylinders. In especially in the low rpm range, this lowers flushing losses in the combustion chamber and guarantees adequate exhaust gas flow to the turbocharger. Increased torque and dynamic engine response are the outcomes.
When driving at a moderate speed, the technology in the 1.4 TFSI serves to deactivate half of the cylinders, which lowers fuel consumption. While the active cylinders run at the greater efficiency levels found in higher load regions, the deactivated cylinders typically operate without losses, such as compressed gas springs.
This technology is also featured in the 4.0 TDI. Here, the two turbochargers are controlled by the Audi valvelift system and switched in accordance with a staged plan. A dual-flow manifold system contains distinct channels that carry the exhaust gases that each cylinder emits from its two exhaust valves. One of the two turbochargers is supplied by every channel. The AVS maintains one of the two exhaust valves closed at low loads and engine speeds so that the whole exhaust flow reaches the so-called “active” turbocharger. The second exhaust valve opens as engine speed rises, turning on the second turbocharger in the process. When necessary, additional AVS units mounted on the intake camshafts control how much intake air is charged into the combustion chambers.
B-cycle process
Audi’s B-cycle combustion technology is an efficiency innovation for gasoline engines. It has been especially created for driving in the part-load range, which predominates during everyday driving. Fundamentally, the approach is comparable to the Miller cycle. However, by incorporating more compression, turbocharging, and the Audi valvelift system, Audi engineers have radically upgraded it (AVS). The outcomes: Drivers who drive in a conservative manner enjoy the benefits of a small displacement engine’s fuel efficiency; on the other hand, those who drive aggressively enjoy the dynamic performance of a large engine.
Three TFSI enginesa 2.0 TFSI variation, a 3.0 TFSI V6 engine, and a 2.9 TFSI with biturbo chargingutilize the B-cycle combustion method. The combustion process’ primary characteristic is an unusually quick opening time during induction in part-load. Before the pistons hit bottom dead center, the intake valves of the V6 TFSI already close at a crank angle of 130 degrees (BDC). Throttle losses are decreased by this as well as higher induction manifold pressure. Since there is still just a little amount of new air being introduced, the compression phase doesn’t start until the piston has passed the BDC point. This enables combustion to occur with a relatively small combustion chamber capacity and a high geometric compression ratio of 11.2:1. The lengthy expansion phase is in contrast to the brief compression phase. Greater engine output at the same fuel consumption is the end result, which greatly increases efficiency.
The lower cylinder charge in the traditional Miller cycle reduces torque and power output. By utilizing turbocharging and the two-stage Audi valvelift technology, Audi has countered these consequences (AVS). The AVS of the V6 TFSI closes the intake valves later under higher load and engine speed; the opening time is raised to 180 degrees crank angle in the 3.0 TFSI and to 200 degrees in the 2.9 TFSI. Valve lift rises from 6.0 to 10 millimeters at the same time. The engine revs vigorously and produces an amazing output as the cylinder charge rises significantly.
The B-cycle combustion mechanism in V6 engines heavily relies on the injector’s central location in the combustion chamber. This creates a shape near the intake valves that, when combined with the inlet ducts, allows for focused swirling of the gas charge, improving combustion.
Cylinder on demand
Cylinder deactivation is a component of the efficiency system cylinder on demand (COD). It is used in some of Audi’s engines, including the 1.4 TFSI and the 5.2 FSI. The mechanism disables half of the cylinders in the top gears at low to medium engine speed and load. The four-cylinder engine only uses two cylinders when operating COD. One of the cylinder banks in the V10 is disabled.
Due to the Audi valvelift technology, the COD system also closes the valves in the TFSI in addition to turning off fuel injection and ignition. The cam units are moved by pins that are extended by magnets. These sleeves engage into the spiral curves on the outside of the cam units to transfer two different cam profiles several millimeters onto the camshafts. The valves are kept closed by the valve springs when the profiles, also referred to as “zero-lift” profiles, rotate over them.
The driver hardly even notices the switchover because it just takes a few milliseconds. The operating points in the active cylinders one and four change to higher load, increasing efficiency, while the deactivated cylinders virtually follow with no losses, such as compressed gas springs at low pressure. The deactivated cylinders are revived when the driver steps on the gas pedal. In the customer’s actual driving, the COD system can cut fuel usage by several tenths of a liter per 100 kilometers.
S tronic dual-clutch transmission
With the S tronic dual-clutch transmission, you may have the efficiency of a manual transmission with the ease of an automatic. It comes in a wide variety of types and variations with six or seven gears. For engines positioned longitudinally, Audi has created a customized version of its seven-speed S tronic transmission. The gear wheels for every gear are positioned sequentially on one output shaft in this design. On the other hand, the four variations for transverse mounted engines have a design with two output shafts. This makes construction more compact. There are three versions of the six-speed S tronic for transverse engines, and there are two of the seven-speed version. Three types of longitudinally installed engines are also available, one of which is made specifically for quattro technology and another of which is mounted at the back of the R8 as a sporty version. What the consumer wants in the car and the torque to be transmitted determine which variant pairs best with which engine.
The S tronic features two multi-plate clutches that control various gears. For the odd-numbered gears 1, 3, and 5, the massive K1 clutch distributes engine torque to the gear wheels through a solid shaft. Around the solid shaft rotates a hollow shaft. The K2 clutch, which is either inside the K1 clutch or parallel to it, is where it is attached. The even-numbered gears 2, 4, and 6, as well as reverse, are driven by this K2 clutch. Although there is always activity in both transmission subunits, there is only ever one connected to the engine. For instance, the second transmission structure’s fourth gear is already engaged while the driver accelerates in third gear. As the clutch adjusts, the shifting process happens. While K2 engages, K1 disengages. They are completed in just a few hundredths of a second and with almost little loss of propulsion power. The S tronic shifts so quickly, easily, and comfortably that the driver rarely notices when the gears shift.
The electronics and hydraulic actuator units are housed in a small, sturdy unit called the mechatronics module. The gear shift’s speed may be adjusted thanks to its control concept, which also allows for fine control of the necessary force. The multi-plate clutches are operated with the highest level of accuracy. The seven-speed S tronic is extremely responsive when navigating and operates in stop-and-go traffic as well.
There are numerous applications for the seven-speed S tronic. The “D” and “S” programs are available in automatic mode. To manually shift, drivers can utilize the shift paddles or selector lever on the steering wheel. The high-performance models also have Launch Control, which maximizes the car’s acceleration power when it starts from a standstill. Engine rpms up to 9,000 are supported by the sportiest seven-speed S tronic for longitudinally mounted engines.
The S tronic has many advantages in all of its variations, including a high level of efficiency, clever management, and a wide spread with high gears and lengthy gear ratios. As a result, the advanced transmission can frequently increase fuel efficiency when compared to a manual gearbox. Further increasing efficiency, its two dry clutches don’t require their own oil supply to function. The Audi start-stop mechanism is coupled with all S tronic iterations. The most recent S tronic for longitudinally mounted engines providesshift-by-wire technology in addition to an unique pressure reservoir system, which is a requirement for many assistance systems that lead to assisted driving.
Electric all-wheel drive
The electric all-wheel drive combines an all-wheel drive’s grip and driving characteristics with a single-axle drive’s efficiency. It provides the optimal drive torque distribution between the two axles is continuously and totally variable regulated. When compared to traditional quattro technology, it only takes about 30 milliseconds between the system sensing the driving situation and the torque from the electric motors kicking in. The rationale is that with electric all-wheel drive, electricity is simply dispersed rather of a mechanical clutch being engaged. And it only takes a tiny bit of time. The complete quattro performance is therefore ensured, even in instances where there are abrupt changes in the coefficient of friction and harsh driving conditions.
To attain the best efficiency, the Audi e-tron often uses its back electric motor. The drive torque is typically distributed with a bias toward the rear axle for efficiency reasons. The electric all-wheel drive will shift torque to the front axle as needed if the driver requests more power than the rear electric motor can provide. Additionally, this occurs in advance of slide occurring in snowy circumstances, when cornering quickly, or if the automobile understeers or oversteers. The wheel-selective torque management works in tandem with the electric all-wheel drive to provide excellent traction in a variety of weather conditions and on varying terrain.
Electric powered compressor
When there is insufficient power for a significant torque build-up in the exhaust stream, such as during engine start-up and acceleration at very low engine speeds, the electric powered compressor (EPC) supplements the work of the turbocharger(s). As a result, it allows for immediate responsiveness and dynamic start-up performance. Sporty drivers will value the passing power and quick power delivery while exiting a bend. EPC technology helps drivers maintain low fuel usage and low revs by preventing excessive downshifts.
A 48 volt continuous voltage is used by the EPC. It is located behind the intercooler in the intake air route and is operational in either of the following two operating states: The bypass closes and the EPC precompresses the air flow during startup. The combustion chamber will now be filled to a greater extent. The bypass flap closes and the intake air goes into the EPC, where it is compressed a second time, when the load needed from the accelerator is high while the amount of energy in the exhaust gas is low. The compressor wheel of the EPC is accelerated to up to 70,000 rpm in around 250 milliseconds by a small electric motor with an output of up to 7 kW.
What does Audi’s S mode do?
S mode modifies the transmission’s shift points. It responds more sportily since it holds each gear for longer while accelerating and downshifts earlier when slowing down. similar 6 gears The gas mileage will be slightly lower than in non-S mode because you’re in a lower gear for a longer period of time. I’m done now.
Are driving Audis enjoyable?
This question would have been quite simple to answer twenty years ago. You would purchase a BMW if you desired the best performance and an enjoyable driving experience. You probably bought an Audi if you needed the extra all-weather grip that an all-wheel drive system provides because you live in a snowy area. But it’s no longer nearly that simple. Audis today are fantastic to drive. They have strength and agility. They handle well, are enjoyable to drive, and enjoy being pushed aggressively. BMW has also made significant investments in all-wheel drive technology, which are now available on all of its sedans and, obviously, its SUVs. When it came to interior design, Audi used to have an advantage over BMW, but that is no longer the case.
However, BMW must be given the advantage. In contrast to Audi’s restrictive front-wheel drive architecture, the brand continues to use rear-wheel drive in all of its models because it offers better balance, more responsiveness, and consequently superior handling. The engine is typically moved further forward in the vehicle’s construction when it is built on front wheel drive platforms, like those used by Audi in its sedans and the well-liked Q5. This results in worse handling and a sluggish response since more weight is placed on the car’s front tires. Do not misunderstand, please. Audis aren’t unwilling to perform; they just don’t provide the same level of sophistication in engineering and skillful dynamic tuning as BMWs do for the discerning enthusiast driver.