Impact of Motor on Torque and Performance in an Electric Vehicle

Many people are opting for Electric Vehicles (EVs) as they are emission-free and due to their low running cost. However, there are people who are enamoured with the acceleration & overall driving experience of electric cars. In this blog, EVJoints brings you an insight into what gives an electric car the oomph, the thrust, the torque when you hit the accelerator.

What is torque?

In a conventional fuel-powered vehicle, torque is the force produced by the engine that translates into acceleration. It is essentially what gets your car moving from a standstill. For example, when you’re at a traffic signal and the light turns green, torque is what launches your vehicle forward.

In an electric vehicle (EV), torque is produced differently than how it is in a conventional fuel-powered vehicle. Instead of the engine, an EV generates torque through an electric motor powered by a battery.

Why is torque important in an EV?

In an EV, torque determines how quickly the wheels can start spinning and accelerate the vehicle.

How is torque generated in an EV?

Unlike fuel-powered engines, which need to rev up to reach peak torque & power, electric motors deliver maximum torque instantly. Electric motors generate a magnetic field that directly drives the rotor, producing immediate rotational force (torque) without the lag of mechanical components like a clutch or multi-gear transmission.

EVs typically use a single-speed system rather than a multi-gear system, so the motor’s torque is always directly available to the wheels. The absence of gear shifts eliminates delays, making the power delivery instantaneous.

How does motor power & torque work together to define an EV’s performance?

Motor power & torque in an EV are interconnected. A motor with massive torque, even if power is moderate, can deliver neck-breaking accelerations.

The instant torque of EVs is why they often outpace internal combustion engine (ICE) cars in short sprints.

How does torque in an EV compare to that in a petrol or diesel car?

Torque in an EV is generated, delivered & experienced differently compared to a petrol or diesel car. This is mainly due to the fundamental difference between an electric motor and an ICE. Electric motors produce torque through electromagnetic force. When current flows through the motor’s stator, it creates a magnetic field that instantly turns the rotor. ICEs generate torque via combustion, where fuel and air ignite to push pistons, turning a crankshaft. Here, the torque is rarely instant.

What role does motor efficiency play in the overall performance of an EV?

Motor efficiency in an EV plays a vital role in overall performance by determining how effectively electrical energy from the battery is converted into mechanical power at the wheels. It impacts range, acceleration & top speed.

Can higher torque result in faster battery depletion in electric cars?

Yes, higher torque can result in faster battery depletion in electric cars. EVs excel at instant torque, but rapid acceleration uses a lot of energy.

Each acceleration blows off a lot of energy to overcome inertia, disproportionately draining the battery compared to steady driving. Hard acceleration can cut range significantly.

How does terrain impact the performance of motor power & torque in EVs?

Terrain significantly impacts the performance of motor power & torque in EVs by altering the energy demands of the motor, affecting acceleration, efficiency & range. The interplay between torque, power & terrain comes down to how the EV overcomes resistance across flat roads or hills.

On flat roads, sustained power keeps speed steady and demands less from the motor thereby preserving range.

Scan the barcode and download the EVJoints app to find 6,000 EV charging stations across various networks.

Click & download the EVJoints app to find 6,000 charging stations.

Sustained driving on an uphill terrain demands continuous power output. Higher torque is vital to accelerate and maintain speed on uphill terrains. This can push motors to peak output draining the battery fast. For example, the Nissan Leaf electric car comes with a claimed range of 243 km, but this range is significantly impacted during uphill climbs, with a potential drop of 20-30% compared to flat-road conditions. So, if you’re driving a Leaf in a hilly area, it is likely to offer a range of 193-210 km instead of the claimed 243 km.

What are the benefits of instant torque in city driving conditions?

Instant torque in EVs offers multiple advantages in city driving conditions, where stop-and-go traffic & frequent acceleration dominate. Unlike internal combustion engine vehicles, which need time to build torque through revs & gear shifts, EVs deliver maximum torque the moment you press the pedal. City driving involves constant starting & stopping. Instant torque eliminates lag from gear shifts or clutch engagement, providing jerk-free movement.

Do all EVs offer the same level of motor power & torque?

No, not all EVs offer the same level of motor power & torque. It depends on the type of EV, battery size, motor type & the EV’s intended use. Power & torque are tuned to match the EV’s purpose, much like how ICE vehicles differ between a hatchback and a sportscar. For example, a small electric car like MG Comet EV (with a 17.3 kWh battery & a 110 Nm single motor) serves a different purpose than a BYD Seal (with an 82.5 kWh battery & 670 Nm dual motors).

How can drivers maximize motor power & torque for better efficiency?

Maximizing motor power & torque for better efficiency in an EV involves smart driving habits and understanding the EV’s power delivery. Electric motors deliver peak torque instantly, but slamming the pedal burns energy, draining the battery fast.

Gradual throttle input keeps torque & power in the motor’s optimum spot, reducing energy wastage. Ease into the accelerator rather than slamming it.

What is regenerative braking in an EV?

Regenerative braking in an EV is a system that recovers energy during braking and uses it to recharge the battery.

How can regenerative braking enhance an EV’s efficiency?

Regenerative braking plays a vital role in enhancing efficiency in EVs by recovering energy that would otherwise be lost as heat. This system leverages the electric motor’s ability to act as a generator, converting kinetic energy from the vehicle’s motion back into electrical energy to recharge the battery.

What is the role of driving modes on power & torque delivery?

Driving modes in EVs significantly impact power & torque delivery by adjusting how the motor, battery & software manage energy output, responsiveness & efficiency.

These modes, typically labeled ‘Eco’, ‘Normal’ & ‘Sport’, adjust throttle, torque limits, power distribution and sometimes regenerative braking strength. The result is a tailored driving experience that can prioritize efficiency and performance, depending on the driver’s needs. For example, according to an Indian Express report, the Tata Curvv EV offers a range of 376 km in Sport mode, 396 km in City mode and 420 km in Eco mode.

Comparing performance of budget EVs vs premium EVs:

Comparing the performance of budget EVs and premium EVs involves looking at key metrics like torque, power, acceleration, top speed, range & efficiency. Budget EVs prioritize efficiency & affordability, while premium EVs prioritize performance. 

Budget EVs typically use single motors with modest torque & power to keep running costs down. Premium EVs feature dual or quad motors, delivering instant torque & sustained power. For example, the Tata Tiago EV comes with just one motor, whereas premium EVs like BYD Seal, Hyundai IONIQ 5 & Kia EV6 come with dual motor variants as well.

Conclusion:

In an EV, the motor is a critical component for performance, efficiency, and the overall driving experience. Without a capable motor, an EV won’t function effectively. It delivers instant torque, giving EVs their trademark acceleration.

For more insights on EVs & EV charging, visit EVGuide by EVJoints.