Electric Vehicle Transmission
Topic: Electric Vehicle Transmission
Electric Vehicle Transmission
The first time you get behind the wheel of an electric vehicle, you might not even have access to a gear lever or stick to allow you to swap gears. You won’t notice the transmission moving gears if you press the accelerator instead of the “gas pedal.” What about gearboxes in electric vehicles?
What you ask has an impact on the answer. A search on reliable automotive websites will provide a variety of replies, including “no transmission,” “a transmission of some kind,” and “a one-speed gearbox.” In this article, we’ll set the record right and uncover the truth about the electric vehicle’s source of electricity.
Defining what a transmission is and does help to get things started. Every automobile has a gearbox in the purest meaning of the word, as a mechanism that transfers power.
As the energy source rotates, it is sent through gears to a differential, the unit that drives the wheels. It’s not uncommon to hear “manual transmission” or “automatic transmission” as the portion of an engine that swaps gears between low and high-speed or forward and backward. The situation becomes murky at this point.
Using a Standard Drivetrain
To keep from stalling or overheating, an internal combustion engine in a gas-powered automobile must revolve at various rates. This includes neither turning too slowly nor rotating too rapidly.
Between 500 and 7,000 rotations per minute, that’s the range (RPM). The transmission shifts between lower and higher gears to compensate for this constraint.
The lowest gear’s rotation is slower than the engine’s, allowing the engine to run at high enough RPMs to avoid stalling. Lower gears have slower rotational velocities due to their larger size, which means that they must propel the vehicle forward from a stop with greater effort but less speed to the wheels.
When in “overdrive,” which rotates faster than the engine, the top gear is the smallest and allows the automobile to go at high speeds without overheating. Engaging the clutch disengages a gear in a manual transmission car so that you can transfer gears.
An automated transmission performs the same function but without the driver’s involvement.
Is There a Science to the Electric Vehicle (EV) Motor?
Electric cars are known for their quiet, smooth, and fast acceleration. That’s because electric vehicles have a different propulsion system. The key distinction between electric vehicles and gasoline-powered automobiles is that the fuel source is the primary difference between both.
Whenever you step on the gas pedal of an electric car, the battery’s power is transmitted to the electric motor, which causes it to spin fast.
Most electric vehicles have a single AC (alternating current) motor and gearbox. Since it is a collection of gears that transmits the motor’s rotation to the wheels’ rotation, the gearbox is sometimes referred to as a transmission.
Because the gears in the gearbox are constantly linked to one another and hence rotate simultaneously, it is more correctly referred to as a single-speed gear reduction unit.
Ten to one is a typical gear ratio for reducing the motor’s RPMs from the more manageable wheel RPMs. This means that the car does not have a clutch, a disengaged gearbox, or a change between different ratios based on the demands of the vehicle.
Is It Possible to Go Backwards?
There is no need for reverse gear in an electric car because the motor uses alternating current. The motor’s only action is to reverse the direction of rotation.
An AC motor can rotate at speeds of up to 10,000 RPM or higher. A 2021 Tesla Model S Plaid’s 23308 RPM motor is one of the reasons behind the car’s top speed of 200 mph. At speeds between 30 and 40mph, a “sweet spot” exists when enough torque and speed are in balance.
There is no transmission to slow the vehicle down, so it accelerates smoothly and quietly without the need to shift gears.
The friction (and thus wear-and-tear) associated with changing gears is reduced with no gearbox. As a result of the seamless transition, an electric vehicle’s forward momentum is better maintained than it would be with conventional gear shifting.
Compared to the energy stored in the gasoline in a car’s tank, 77% of the electricity stored in an electric vehicle’s battery is used to move the car ahead.
All except a little amount is used to generate heat. An EV’s motor to wheels power transmission efficiency ranges from 89% to 98 per cent, but the equivalent procedure in an ICE automobile from the engine to wheels is just 14-26% efficient. 2
Do Electric Vehicles Have Gears?
Whether the vehicle is an ICE or an EV, it requires more torque than speed to get the vehicle moving from a standstill and more speed than torque once it has a bit of forwarding momentum.
So, wouldn’t it be better if electric vehicles had more than one gear? If you’re willing to pay more money upfront, you’ll be able to get a system that’s more complicated, heavier, more labour-intensive, and more expensive to maintain.
Newer electric vehicles, such as the Audi e-Tron GT and the Porsche Taycan, feature multiple gears, allowing them to transfer more power to the wheels to boost acceleration, which improves acceleration. Even a multi-gear manual gearbox is planned for the Jeep Magneto.
All-electric Formula E race vehicles also have gearboxes.
Even while electric vehicles, particularly 18-wheelers, may have several gears and transmissions to accommodate the vast range of RPMs achievable with an electric motor, they may have two for torque and cruising speed.
A single-speed gear reduction will be used in the next Tesla Semi truck. A similar argument may be made for smaller automobiles that must tow or transport large cargo.
Transmissions that can be adjusted continuously
Continuously variable transmissions (CVTs), a type of automatic gearbox that accelerates smoothly from one speed to the next by employing pulleys instead of gears, are available on some ICE and hybrid cars.
CVT systems for electric cars have recently been invented to enhance torque at lower speeds to accommodate bigger vehicles and loads. Because of this, EV developers no longer have to discover a “sweet spot” balance between torque and speed.
As CVT systems promise an improved economy, this is a primary worry of potential EV buyers: increasing the range of their vehicles.
Rather than using many gears, use multiple motors.
Rather than relying on a gearbox that wastes energy transferring electrons between gears, some EVs use numerous motors with varying gear ratios to generate more or less torque, depending on the vehicle’s demands. Many Tesla cars, such as the high-performance Lucid Air, have dual or tri-motor variants.
Moreover, unlike ICE vehicles with gears, EVs with several motors may use them all simultaneously, increasing the vehicle’s speed and torque and its traction and agility. To make “tank turns,” the Rivian electric pickup trucks have motors linked to each of their wheels.
Electric Vehicle Transmission
There are several reasons why electric vehicles benefit from transmissions.
First, I’d want to explain why electric transmissions are a positive thing before going into my own experience.
Because Tesla automobiles lack a gearbox, many Tesla enthusiasts believe that transmissions are unnecessary or even bad. It can’t be necessary since they’re doing just well without one.
With a closer look at Tesla’s twin motor solutions, you’ll discover that they have a gearbox of some form and reap the benefits of that transmission in a fairly novel way.
An electric motor can work at a far larger speed range (RPMs) than a gas engine. You don’t need several gear ratios to avoid over-revving the electric motor like you would over-rev a gas or diesel engine when you roll down the road.
At some point (typically before 40 MPH), shifting to a higher gear is necessary to keep the engine from exploding. Transmissions aren’t necessary for EVs because they have one gear that covers the whole range of the vehicle.
Even though an electric vehicle (EV) may operate without numerous gear ratios, Tesla is aware of this. Low-speed acceleration can be improved by directing more power to the rear wheels, which are better at launching.
Second gear is created when the vehicle travels at high speeds (highway driving) by directing power to the front motor, which has a higher gear ratio. The front motor in performance versions is also smaller and more appropriate for this job.
Porsche pushed this notion a step further by installing a two-speed gearbox in the rear-drive unit. Both the front and rear drive units have an 8.5:1 gear ratio, but the rear motor can go as high as 15:1, allowing for much higher torque multiplication during the first launch before shifting to a gear that’s taller than the Teslas for highway cruising.
In addition to this and other criteria, Edmunds gave the Taycan an excellent range rating. The Tesla, even in its most economical driving mode (which the EPA does not employ), had a far longer highway range than expected, while the former fell just shy of the latter’s EPA predictions.
After two gears, what happens next?
Are three, four, or even five gears better for an electric vehicle? As we’re learning, the answer to that question is, “Yes.”
More and Better Is on the Way.
Aside from the electric mode, the car still had an internal combustion engine (ICE) that had to be used to power the vehicle. However, that doesn’t imply that manufacturers aren’t working on complete EVs with gearboxes.
Many sites on the internet predict a 3 or 4-speed automatic electric transmission. However, prototypes show us that there is a lot more variability available.
Jeep’s Magneto concept is the most outlandish item on display right now. Even though it is a pure electric vehicle (and not a hybrid), its electric motor is connected to a manual transmission.
Remember that electric motors cannot stall, so this may sound bad at first. As you approach a stop sign or red light, leave the manual transmission in the drive and come to a complete stop.
Step back on the narrow pedal when you’re ready to resume your journey. Shifting would be necessary only when entering the highway or doing a hard launch in first gear.
Additionally, building more electric vehicles with a gearbox would make it easier for folks who have previously been dubious about EVs to get behind the wheel of one. We can persuade more individuals to make a move if we make it easier to maintain their current habits.
People Also Ask:
What type of transmission is used in an electric vehicle?
Single-speed and multi-speed transmissions are the two most common gearbox types in electric cars. Fuel economy, motor efficiency, speed-torque variation, power, cost, weight, etc., are all elements that impact the transmission.
Why not use a transmission on electric vehicle?
Due to the so-called “engine” in an electric automobile, an electric motor. Because electric motors provide power quickly, they eliminate the need for the revving action required by internal combustion engines to create torque.
What is a one speed transmission electric vehicle?
The drivetrain is a major distinction between conventional automobiles and electric vehicles. Most electric vehicles (EVs) do not feature multi-speed gearboxes. Instead, the electric motor is controlled by a single-speed gearbox.”
Can an electric vehicle have a manual transmission?
With no clutch or gearbox, electric cars can only have a single gear (drive) and a reverse, like a normal diesel or petrol vehicle. There is no need for a manual gearbox in electric automobiles because they don’t have one.
Electric vehicle conversion without transmission.
Since most commercially available electric automobiles only have one gear, there is no need to change. It doesn’t require a clutch or an automatic transmission counterpart because it’s in a fixed gear. This also reduces weight, complexity, and the number of moving elements in the system.
Electric vehicle transmission efficiency?
Transmission efficiency is commonly assumed to be 95 per cent in studies of electric cars.