Why Are Electric Motors Better?

Why Are Electric Motors Better?

Electric Motors are better because they require little to no maintenance, reduce emissions and delivers a huge amount of instant torque.

There’s a lot of talks these days about EVs versus ice cars and the is almost entirely revolve around the battery, the capacity of the range, that kind of thing.

And the batteries are obviously very important, but
the batteries aren’t what make this face happen.

That my friends are the electric motor at work. It’s really funny that you don’t hear more about the electric motor.

You know, when, when gear heads get together and talk cars, it’s all displacement and valve timing and VAs and inline-six. It is all about the engines.

Either the owners don’t really talk about the motors that much, at least not the conversations I’ve had. It’s usually just about how fun they are to drive and how better they are than nice cars.

But it’s the motor that makes it more fun. And most people have no idea how they work.

So in this article, I just want to show a little bit of love to the electric motor, how they work and why they’re just better.

Just like there are a whole bunch of different types of internal combustion engines. There are many different types of electric motors, but before I go into that, do you know the difference between a motor and an engine?

Supposedly a motor runs on electricity and an engine runs on combustion.

They’re often used interchangeably, but if you ever hear somebody saying electric engine, it really should be an electric motor.

I’m glad you’re with me on that. So while the combustion engine, let’s just say the V8 engines are really complicated and made up of hundreds of different parts.

You can kind of go into the basics of the four-stroke engine and show how it works and you can get the fundamentals down and then just kind of extrapolated out from there.

And that’s what I’m going to do here for electric motors. I’m just going to start with the basics and then talk a little bit about how the different motors are different.

Let’s start this off about as basic as we can possibly go take a magnet, a magnet, as we all know, has a North pole and a South pole, and these poles are attracted to opposite poles.

So if you’ve placed a cylinder around this magnet and had a North and South magnets on either side, that magnet in the middle would line up with those opposite poles.

Now, if you want to rotate the magnet, all you have to do is rotate the cylinder and the magnet would rotate as well because it’s magnetically locked well. That’s all well and good. But of course, something still has to turn that outside cylinder.

Luckily, magnetism is only half of electromagnetism. If you run electricity through a wire, it creates a magnetic field loop that wire around and that field gets twice as strong.

Keep looping it hundreds of times over, and you can create an extremely strong magnetic field.

Now let’s go back to that cylinder. I was talking about before and replace those two magnets with electric coils, creating a North end and a South end, run current through it and you’ve got a strong magnetic field.

Now let’s place that magnet in the middle, this time in the form of a rotor with North and South poles on it, once again, the opposite poles will attract only this time. You can turn off the effect by shutting off the flow of electricity.

By the way, the outside cylinder that I keep referring to that’s actually called the stator. The part on the inside that rotates is called the rotor. So the stationary part is the stator.

The rotating part of the rotor for once engineers made the terminology really simple.

Alright, so now we need to make that rotator rotate. And this is where the alternating current comes in, alternating current or AC is exactly what it sounds like.

The flow of electricity alternates directions in a wire it’s positive when travelling one direction, negative on travelling the other direction, magnetically positive and negative correlates with North it’s out.

By the way, the speed at which the current alternate it’s just called frequency, which you can raise or lower.

However, you want that frequency is measured in Hertz. So if you’re running alternating current through the coils in our state, or the magnetic field will flip in the coils, causing the rotator to flip as well.

Now, technically we’ve got a motor that rotor is spinning. Of course, you could easily flip back the other direction and it’s not exactly a smooth ride. For that, you got to add more coils.

With three sets of coils alternating their polarity in phases, you now have a rotating magnetic field or RMF, which carries the rotor along with it. This is a three-phase AC induction motor.

So named because the electrical energy is induced on the rotor. If you want to speed up the motor, just change the frequency of the alternating current.

This was the brainchild of the one and only Nikola Tesla, which is why a certain car company named themselves after him.

Now, again, just like the forest stroke engine is the basis for a million different types of internal combustion engines this is the basis for a million different variations of electrical motors.

For example, what I just described as a type of permanent magnet motor, because it has magnets on the road, or that gets pushed and pulled by the RMF.

Another type is called a synchronous motor, which has its own coils in the rotor that creates its own magnetic field that locks in sync with the coils in the magnetic field and the RMF created by the stator.

It’s also a type of motor that uses coils in the rotor that creates an RMF that reacts with permanent magnets in the stator.

So it’s basically the opposite of what I just described. And then there’s a switched reluctance motor, which is actually what’s in the Tesla model three.

And there are also some that flip the rotor in the state or with the rotor actually on the outside of the stator, which is in the middle, lots of different types of motors.

If you want to know which motors go in which EVs, please check this article: Which Electric Motor Powers Your Electric Car.

What are the advantages of electric motors?

Now, when you talk about the advantages of electric motors, really the, probably the biggest one is just that there are fewer moving parts.

You’ve got a rotor and a stator and one of them rotates and that’s it. There’s no oil to change, no timing belts to replace no spark plugs, shall I continue?

Fewer moving parts means fewer things to break, which means that electric motors are easier to maintain and cheaper over the long haul.

In fact, many of them are rated to go for a million miles and adding to the simplicity as I was saying before if you want to adjust the speed, all you have to do is adjust the frequency of the alternating.

Current electric motors have a speed range from zero up to around 1800 RPM. So gears and transmissions are completely unnecessary.

This also means that technically EVs can drive backwards just as fast as they drive forwards. Although they’re software limited for obvious reasons.

Electric motors are smaller, or you should say that they are size adjustable so they can fit any space that you need. The smaller size means you can easily put more than one motor in there. Many Teslas have a motor on the back and a motor on the front for all-wheel drive.

The Rivian Pickup Truck will actually have a motor on every single wheel. In fact, there are some designs for motors that go inside the wheel, so the wheel itself is a motor.

Electric motors give you full torque from a dead stop, which is why you get those sick drag race times. Electric motors are quieter, meaning they make almost no sound until you put the pedal to the floor.

You can also regeneratively break with electric motors, meaning except for emergencies. You almost never press the brake until you get down to like five miles an hour. This not only makes your brakes last, almost infinitely long. It also reduces the amount of brake dust that winds up, you know, particulates in the atmosphere.

And last, but probably most, electric motors are just way more efficient than gasoline engines because you’re not pushing a series of pistons around and moving hundreds of moving parts, each of which creates friction and lose energy through heat.

Electric motors actually get 80 to 90% efficiency. Whereas ice cars get between 20 and 30% efficiency. But before it sounds like I’m being too hard on ice engines. Let me give a little talk to the internal combustion engine.

This is a message out there to all the thousands of people who have iterated on and worked on and improved on the internal combustion engine over the years.

Obviously that’s a lot of people, far too many for me to list here. So I’m going to ball all them up into a fictional character that I’m going to name combusting McGee. Mr McGee, the engine you created is a work of genius. No snark, no irony.

Here I am being completely sincere. The internal combustion engine is a work of genius.

Not because it changed the world in every conceivable way, which it did, but because it might be the height of human engineering. We want it to go faster than a horse.

So we figured out a way to create tiny little explosions inside a metal tube, to push another little hunk of metal down, that would push another little hunk of metal, that would push another little hunk of metal up, which will get pushed down by another little tiny explosion.

And we figured out how to tie in these things to the millisecond over, across the entire thing, pushing other pieces of metal around that pushes another piece of metal around the winds up turning some wheels and it moves this entire hunk of metal forward.

There are so many parts asserting so much force across such high temperatures. It is an absolute modern Marvel that this thing even works.

And that just shows how well built this thing is that we were able to just muscle through this problem and make it work is astonishing to me.

And it did change the way we live in this world. Maybe more than any other invention in human history.

So in my humble opinion, the internal combustion engine deserves a lot of respect and you combusting Magee is an absolute genius. But it’s time for it to die. With the exception of specific use cases, the electric motor is just flat out better.

That’s why there’s so much fun to drive and that’s why it’s slowly starting to cover the entire industry. In fact, there were a lot of hybrid drive trains out there that have a gasoline engine, but it basically is used to power a generator that sends electricity to the electric motor, which is what drives the car.

Many diesel locomotives are hybrids for this very reason. And a lot of high-performance car companies are starting to embrace that technique just so they can keep up with the EVs on the road now.

Obviously there’s a long way to go before all cars are running on electric motors and ice cars will probably still be around for a long time.

I think in 10 to 20 years, gas cars will kind of be like manual transmission cars today, like more of a niche product, which I get, honestly, every car I’ve ever had my entire life until my Tesla Model 3 was a manual transmission car.

I just liked switching gears. I just liked it even though the technology was completely obsolete. Which I truly believe is a designation that’s going to be applied to ice cars in the not too distant future.

Resources:

https://books.google.dk/books?hl=da&lr=&id=0Y_MBQAAQBAJ&oi=fnd&pg=PP1&dq=electric+motors&ots=aAfzgd9_P9&sig=-ZLmJ4-_d5d6E7aio5bNDy_529w&redir_esc=y

https://www.osti.gov/biblio/6754096

More about electric cars

Auther:

Morten Pradsgaard

Morten has been working with technology, IoT and electronics for over a decade. His passion for technology is reflected into this blog to give you relevant and correct information.

Read more...