Hyundai Just Gave An Amazing Explanation Of How EV Motors Work 

Electric powertrains are simpler than internal combustion engines, but they’re no less impressive when it comes to the technical wizardry that helps you go places. Batteries, of course, are at the heart of any EV, determining how far they can go or how quickly they juice up. But it’s a vehicle’s traction motors that actually harness that energy and translate it into forward motion.

The internals of these motors are fascinating and, I’d reckon, poorly understood by most. Hyundai recently explained exactly how its electric motors on its EVs work, and also outlined the tweaks that enabled the bonkers Hyundai Ioniq 5 N and the Kia EV6 GT performance crossovers. And the video may be one of the best breakdowns of how EV motors work on the internet. 

For starters, the electric motor contains three key components: motor, reducer and inverter. The motor generates torque. The reducer transfers that torque to the wheels, whereas the inverter converts the high-voltage battery’s direct-current (DC) power to alternating current (AC), precisely controlling how and when that power gets used. Hyundai dove deep into the inverter in its latest explainer, saying it heavily influences power distribution and efficiency.

But before we dig into that, this is how an EV actually gets moving: DC power from the battery flows into the inverter, where it’s converted into AC for the motor. When the AC flows through the motor’s coils, it creates a magnetic field that constantly changes thanks to the alternating current, making the magnetized rotor at the center spin. All this happens within milliseconds of when you touch the throttle, delivering that instantaneous response that jolts your head back.

Now, how the vehicle responds after you press the throttle depends on how the inverter is configured, according to Hyundai. The company said you can unlock more performance with higher battery voltage or by increasing current at the motor, but these two approaches can make the drive systems larger and heavier. It can even lead to thermal management complexities.

But a smartly designed inverter can deliver that performance in the way it applies and controls that voltage. The company has designed what it calls a 2-Stage Motor System, which essentially doubles the number of switches—which regulate the power from the battery to the motor—in the silicon carbide inverter from six to twelve. 

In normal driving, the first six switches within the inverter do all the work. Floor it, and the system activates all twelve switches to deliver that neck-snapping acceleration which feels addictive on EVs (And makes your tires wear faster). The extra set of switches helps increase voltage by 70%, the automaker said.

Hyundai claims its 2-Stage Motor System doesn’t add any significant weight either. It condensed nine semiconductor modules into three, shrinking the inverter itself while delivering a lot more power.

For an combustion-equivalent comparison, think of Honda’s VTEC engines. The Japanese automaker’s variable valve timing lets an engine switch between two different camshaft profiles depending on how hard you’re driving. One helps with efficiency at low RPMs, whereas the other kicks in when you floor the throttle. It’s not an exact apples-to-apples comparison, but similar in principle to deliver the performance boost.

For a deeper dive into all of this, the video above is worth a watch. 

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