Motors Blog

Hi there, good morning. A crazy idea had just popped up in my mind : how about installing a device on atop of a truck, just like on a trolley bus or a tramway? I keep suffering from the Diesel engine's "gifts": these are noisy, vibrate, have "aromatic" and thick fumes ... So, since there are already electric lines along the majority of the roads, why not have a constant fill-up along the way? Maybe it's worth considering. Still, have a good, quiet and happy day all!

The "high performance AC induction motor" has little to nothing to do with "new technology turning the tide". AC induction motors have long been over 90% efficient in 50 hp sizes and up. The difference between one motor at 92% and another at 94% is virtually meaningless, in vehicle market terms. 16 hours duration vs 15.6 makes no market difference.*

Controllers have been highly-efficient for a long time -- they too are a non-issue.

Batteries have always been, and remain, the weak link. Even lithium ion are too heavy and too costly to permit electric vehicles to compete directly with ICE vehicles, under most circumstances. Enabling such direct competition to occur requires substantially new overall vehicle design, in terms of system architecture, fundamental vehicular efficiency, etc.

Motors are fine as they are. In fact, compared to ICEs, they are things of wonder: quite, smooth, efficient, low parts count, simple control systems, etc. Fortunately, a good battery system might be not too far around the corner.

Can advances in motor technology and other key components make them a more viable transportation option anytime soon?

So no, "advances in motor technology" will make little difference; but if "other key technologies" include batteries, then the answer is "of course". But this is anything but news.

* In niches where duration is measured in shifts (rather than in miles), then 20 hours vs 16 can be a significant differentiator: because no one expects 16 hour range to really be 16 hour range, consistently. 20 hours means there is a good probablity of getting through two shifts, often.

Let's not get hung up on definitions - in this case, "efficiency". Yes, batteries are the weakest link in EVs. Since today's batteries are so limited, we could spend some time trying to improve the components that draw power from them. True, many of today's motor designs boast efficiencies in the 90% to 95% range, and controllers boast even higher. But "efficiency" is defined by the amount of power input. If we can reduce power draw then battery limitations become less dire. Today's EVs routinely draw hundreds of amperes depending upon driving conditions - why does this need to continue? Let's not overlook opportunities by assuming that there are no meaningful gains possible.

I could hardly agree more.

It is the tone article with which I disagree. Motors are nearly a non-issue. Batteries are the most obvious issue, but the overall architecture and vehicle design details can compensate.

I'd like to change the face of transportation, and so my trike uses a very small amount of electrical energy to move one or two people (1.1 people being the US average load during commuting). It gets ten miles per kilowatt hour (in contrast to the LEAFs 4 miles per kilowatt hour). So then, the battery pack can be small and less costly (albeit still the most expensive part, by far). This means the vehicle can be lighter and more efficient. A small engine can then recharge the batteries if the daily range is exceeded, so that forgetting to charge, running an unanticipated errand,etc, all become non-issues.

40 mile-per-day range is adequate for most commuters (this is about 15000 miles per year). Those with short commutes never use any gasoline. Those with long commutes (for whom an electric vehicle is not a good option) can then do most of their commuting on electricity and a small amount of it on gasoline. The same factors that contribute to high efficiency (lightness, good aero) when running on electricity contribute to high efficiency when running on gasoline, when the vehicle gets about 100 mpg (in the worst case, gasoline only, mode).

Let a couple factors creep upward (how about three people instead of two?, etc) and soon you get back to a LEAF territory: mediocre overall energy efficiency.