Renault production line of the R240 electric motors mainly for the Renault ZOE electric car. Photo … [+]
As I write articles about electric transportation technologies for Forbes.com, I keep a reminder on my desk of the importance of electric motors to the future of… well, everything. The reminder? It’s a drone, but not just any drone. It’s a bird I bought about five years ago when I first started flying drones, and I plunked down about $40 for it for a simple reason: It’s tiny. I mean, really tiny. Here it is, ready to take flight, with a familiar tech icon for scale:
Tiny, yet airworthy and fun to fly, this diminutive drone is a reminder to me of the ubiquity and … [+]
See? Tiny. In all honesty, I didn’t expect it to fly worth a damn (if at all), so imagine my surprise when it not only flew very well, but it was actually fun to fly, gracefully buzzing around inside my house or outdoors, and it flies for several satisfying minutes on its tiny battery. Even now, years later and with drones a very known quantity, people who see it fly are stunned it works at all. And to think that inside that tiny chassis, there is a sophisticated computer in charge of motion sensors, and a sophisticated motor controller constantly spooling those four tiny, tiny motors up and down to achieve level, controlled flight. Ten or so years ago, such a device was literally still in the realm of science fiction. Now it’s $40. And clearly, much smaller electric motors exist and are in service all around us. And while electric motors are the future, they are really only half the tech story.
Here’s a key point to understand about the enormous difference (and potential) between motors that run on electricity versus any other kind of motor that runs on a fuel that isn’t electricity: Unlike combustion motors that require gasoline, diesel, natural gas or fairy dust, electric motors will become more powerful and efficient as they become smaller, lighter and less complex. Yes, less complex.
That has certainly not been the case for internal combustion engines (aka ”ICE” motors) that require exploding fuels such as gasoline. In general, they have become both larger and hugely more complex as power requirements have risen. If that wasn’t the case, Ferraris, Fords and all the rest would be sporting tiny engines that get 200mpg while going 200mph with little need for maintenance. As you are likely well aware, that’s not the case today – nor has it ever been, or ever will be.
When it comes to making “more power” from liquid-fueled engines that produce power via combustion, there really is no replacement for displacement, as the old saying goes, say what you will about turbocharging, supercharging, intercooling and so on. Even with every modern advancement in place, a gas engine is expensive, large, heavy, very inefficient, ridiculously complex and limited by the potential energy of their liquid fuels. The fact they run as well as they do at all and largely power our world at this time is a true testament to human engineering skills.
But in the end, ICE-powered motorvation is doomed to museums and tall tales from grandparents (us) around the campfire. The evolution of the electric motor – despite being a technology coming up on its 200th birthday – is still in its relative infancy, and future advances are inexorable. Huge changes and advances are coming both in motor tech, battery tech, and the systems to control both parts of the electric drivetrain.
The long view of electric motor tech is that it’s a winding road that will see the development of endless incremental efficiencies and technical development over the years that will make the motors in today’s cutting-edge EVs seem as primitive as the drivetrain in a kiddie car. A small Canadian company called EXRO has developed some important technology along that path of innovation, and the key to EXRO’s technology isn’t a focus on making electric motors, it’s about how the motor is controlled, a facet of the electric powertrain that’s as important as the motor itself – like in my little drone. It’s also an admittedly esoteric technological niche that is none the less seeing robust development worldwide. Here’s an excellent primer on how electric motors work:
I talked with EXRO CEO Sue Ozdemir, who has assembled an impressive team of researchers and advisors that have developed controller technology that they claim will increase power output and efficiency from electric motors made today and in the years to come. Again, they don’t make the motors, they make or modify the electronics that controls how the motors work, known unironically as motor controllers.
With electric vehicles ascendant, and battery tech working overtime to keep up, any reliable technology that increases power output, increases efficiency (and thus: range), or both, would of course be a very hot property. EXRO’s first product, called Coil Driver, is another step toward streamlining the electric motor power train. Coil Driver technology essentially acts as as “electric gearing” for an electric motor… without using any physical gearing. Here’s an overview from EXRO.
Coil Driver works through a motor controller to give electric motors – including existing motors – two torque profiles, also known as torque curves. Typically, an electric motor has essentially one torque curve, and uses physical gearing to modify it for the needs of the vehicle the motor is in (such as a Tesla, or a drone). With Coil Driver tech, that heavy, expensive, complicated gearing can be done away with. “Basically, our technology enables electric motors and batteries to be smarter,” Ozdemir told Forbes.com. “We’re like a new brain” for those critical components, Ozdemir said. The tech uses “coil switching,” which allows motor controllers to control an electric motor at the base coil level. Electric motors are typically made up of coiled lobes of wire attached to the motor’s axle, and surrounded by magnets through which electricity flows. Add more electricity, and the motor spins faster.
By giving an electric motor two separate torque profiles, Ozdemir says the Coil Driver tech can give an electric motor a torque boost at low rpm to get things moving, while also optimizing the motor to work efficiently at high RPM’s for speed. She says this tech would be a boon for smaller-scale electric motors, like those found in those electric scooters in cities and also in ebikes that are now so popular. Take out that extra gearing, and Ozdemir says those electric scooters and some ebikes can get lighter, faster, less expensive and more efficient. EXRO is claiming that in some applications, efficiencies and power output have risen as much as 30%. If the range of your electric car is 300 miles without the Coil Driver tech, the math is pretty simple.
In an electric car, Ozdemir said Coil Driver tech could reduce the need to have multiple motors needed to achieve those hot 0-60 times and a big top speed number. Fewer motors means less cost, and so on. You can start to see the appeal of Coil Driver for anyone putting an electric motor into anything that might move a person or load around. “We’re able to connect into any type of electric motor,” Ozdemir said, and the tech works well in vehicles ranging from electric bikes to electric buses – and perhaps everything in between or even beyond.
Speaking of electric bikes, Ozdemir said that they are now working with electric motorcycle maker Zero, who ostensibly leads the industry at this time. While no current Zero bikes have the Coil Driver tech, future machines could make use of it. Other brands, of course, are showing interest as well, including another electric motorcycle maker, Ohio-based LAND. LAND is not selling bikes quite yet, but they are working on integrating the EXRO tech into their futuristic machines, which will be smaller and more urban-focused than those offered by Zero. LAND has placed an order for 2,000 Coil Driver units with EXRO. If the Coil Driver technology works well with Zero and LAND, expect more companies to take an interest. Currently, EXRO is also working with SEA Electric, Potencia, and others.
Ozdemir also announced that EXRO has another offering in the queue, Battery Control System or BCS, this time focused on controlling batteries. While it’s easy to think of batteries as just a bucket of energy the motor draws from, like a gas tank, the reality is far more complex. Pulling power from a battery is a delicate dance between motor, the battery and the tech that controls the flow of current, and Ozdemir said their new product, due out in Q2 of this year, will allow control of batteries at the cell level, giving power systems gains in efficiency and ultimately, lengthening the lives of those expensive battery packs, including giving them second lives after they meet the end of their service lives in vehicles, which is a huge opportunity to cut down on e-waste and extend the life of the battery in other market segments, such as home backup batteries and so on.
While topics like motor controllers and electric power trains may rank high on the geek/nerd scale, the bottom line is that, like the internet, electric motors and all of the tech associated with them is of vital importance to our modern society – or any society – and indeed to our lives. From the tiny electric motor in your smartphone that causes it to vibrate when you get a text message to the giant electric motors in freight train locomotives, we depend and rely on electric motors to keep things going to a degree few people realize. If EXRO’s tech can make them work better, we’ll all be better for it.
Writer, photographer and technology evangelist. I’m also an avid motorcyclist, car enthusiast and chronicler of the ongoing evolution of mobility technologies.