There is a lot of hype around EVs, but has anyone explained to you how it works? Here are the basics for people who just want to know what they’re buying without geeking out.
There are five major components that separate an electric car from a gas-burning one:
- Battery charger
- Power control unit
Contrary to popular belief, the thing on your garage wall or on a pole in the shopping center is not the charger, it is the Electric Vehicle Service Equipment that provides power to the charger built into your EV. That onboard charger converts the alternating current power provided by the ESVE into direct current power that the battery can produce. That can be done by a slow charge at Level I if the car is connected to a 120-volt EVSE or a faster charge at Level II if it taps into 240 volts.
However, if you use a fast charger, such as a Tesla Supercharger or Electrify America station, that is a DC power connection. These supplies a higher level of current than your home can provide without AC-to-DC conversion required, which is how they charge your car faster.
The battery is the heart of any EV. This largely determines a car high checked rangeusually higher costs and greater weight. It is magic and a curse.
The battery is usually placed as a large flat panel under the belly of the car, inside of which there are smaller modules with many smaller cells. Some cars eschew the belly-pan style battery and shape it more like a piece of luggage that fits into the holes in the car’s body. But the shape and location of the battery is of little importance to the average buyer. What is important is the range provided by the entire vehicle.
Batteries store DC power, whether it’s in a flashlight, phone or car. So the charger must convert AC to DC to recharge the battery and that is also one of the main jobs of the next component, even if it is reversed.
Power control unit
The power control unit is an assembly that goes by different names and is not something that manufacturers usually advertise, but it is important. Its most critical job is to convert the DC power stored in the battery back to AC which is used by most EV motors. This is done by a component called an inverter, one version of which you can use to power your laptop or other household appliances from the 12-volt port on your car’s dash.
The power control unit also interfaces the drivetrain with the accelerator pedal, start button and drive mode controller. And, most importantly, it handles regeneration, which is how an EV returns power to its own battery when riding or braking.
A lot of said Tesla The success is its ability to optimize the different power flows and changes that occur in its EVs, which proves the importance of the least informed component of an EV.
The motor is, of course, what turns the wheels but unlike a combustion car it can have one motor or many in an EV. More motors can make an EV go faster, it can be equipped with sophisticated all-wheel drive, or both. But don’t lift the hood expecting to see a good-looking motor like a conventional car engine. They are usually compact and inconspicuous, often buried out of sight.
The comparison of horsepower and torque between gas and electric vehicles is completely valid. Note how high the torque spec is on any EV you’re considering, given the nature of electric motors and making EVs a kick to drive beyond what their horsepower rating might suggest . And electric cars can deliver most of their torque starting at low RPMs, while gas-engine cars need to be revved up to provide maximum acceleration. Motors are different from engines, which you will notice the first time you drive any EV.
Not much to say here because electric motors don’t really need a transmission. The nature of their operation makes them efficient and powerful over a wider range of RPMs than combustion engines, so they don’t need six, seven or even 10 gears as crutches to help. them to accommodate different speeds or vehicle loads. However, most EVs use a single-speed reduction gearbox to convert the high rotational speed of the electric motors (usually as high as 20,000 RPM) into better road speeds.
No typical transmission, the EV has a drive mode selector instead of a PRNDL. Federal regulations require that any car sold in the US adhere to certain conventions including placing Park at the end of the trip on the drive controller and Reverse next to that. But EV drive controllers often have unconventional shapes and can add an unfamiliar position that puts the car in a higher rev mode while driving, as described earlier. yet.
This list may seem extensive but EVs have simpler drivetrains that use 70% to 90% fewer parts than a gas-engined vehicle. That collection of smaller parts often costs more than a gas engine car but as scale drives down EV costs, their inherent simplicity should only turbocharge the curve.