Conventional vehicles are designed with powerful internal combustion engines (ICE) that are intentionally over-engineered and overpowered to produce large amounts of torque at critical yet infrequent times, usually 10-15 seconds at a time.
An example would be starting from a complete stop to merge onto a highway. HOWEVER, a Series Hybrid, outfitted with the new Chorus Meshcon(tm) motor/drive and using ultracapacitors in the design, allows for reversing this overpowering trend.
By incorporating Chorus Meshcon, which can provide 10x the ‘burst’ torque when powered by an ultracapacitor, a Series Hybrid can compete both in "Price" and "Performance" in the mass market due to the unusual features of this new and unique motor. With these two technologies, a Series Hybrid vehicle can be designed around its ‘average’ power requirement and not it’s ‘burst’ power requirement, while still maintaining performance and achieving a much higher gas mileage.
In a Series Hybrid design, the internal combustion engine does not drive a heavy mechanical transmission, but instead directly produces electrical power with an attached alternator, and the resulting electrical output powers the electric motors and/or charges the battery and capacitor bank. The ‘burst’ torque is provided not from the ICE, but from a special and new type of electric motor, the Chorus(R) motor that is making its way from the Aerospace industry to the automotive industry, and will allow Series Hybrids to realize significant gas mileage gains.
So how can a Series Hybrid get much better mileage if it still uses an old-fashioned internal combustion engine to generate electricity? The answer lies in the difference between the *average* power draw of a vehicle, and the *burst* power requirement that is the standard for determining vehicle performance; and Chorus Meshcon shines in this ‘burst’ torque area by uniquely providing up to 10x the standard torque for that burst that would normally come from an overpowered ICE engine in a standard vehicle. .
An internal combustion engine vehicle is sized for its *maximum* power production -- think of top-end hp and torque numbers. Those top numbers represent the "oomph" the car depends on for those brief seconds of maximum (or ‘burst’ torque) acceleration. Carmakers are aware that customers want to have a car that is fast off the mark for merging into highway traffic and other situations, and are wary of downsizing the engine and making a car's performance anemic despite efficiency gains. They’ve learned this painfully from the hostile reviews to very inexpensive, and underpowered cars like some of the old (and >40mpg) Honda Civics, or the Geo Metro. Therefore standard ICE vehicle engines have to be made for that "burst" requirement.
If a typical sedan requires perhaps 25-35 kW of power, but in order to gain market acceptance it needs to apply 4-6 times that power (150kW or more) for a several seconds at a time, then the ICE has to be over-engineered, heavier, and more expensive. Additional efficiency is lost since every ICE has a particular speed where it is most efficient, and this overpowered engine is constantly shifting its rpm which occasionally takes it out of that maximum efficiency zone, which results in poorer gas mileage.
From a mileage perspective, a *small* gasoline or diesel motor can give superb performance, as long as excess energy for that ‘burst’ requirement is stored in a battery or capacitor. A Series Hybrid’s ICE motor would be optimized and tuned for a limited speed and power range, which gives better efficiency (and lower emissions) than today’s automotive engines that have to operate from 500 to 5000 rpm. Therefore a smaller motor, sized like the 50-60hp of a Geo Metro, would easily generate 40+ mpg, yet still throw a medium or large car around with impunity using the ‘burst’ torque from Chorus Meshcon (where the extra power is not drawn from the batteries but rather from the Ultracapacitors) and from the weight savings (from the reduced engineering complexity) that Chorus provides any hybrid vehicle.
The Series Hybrid car approach is fundamentally correct in terms of the powertrain. In comparison, insisting on the "plug-in" approach that requires batteries that do not exist (and if they did would not be affordable) represents numerous limitations, including infrastructure changes and recharge time, plus those additional batteries add hundreds of pounds of extra weight. GM admits that the Volt is likely to top a sticker price of $45k -- and a lot of that is the battery. However, a Series Hybrid could have a ‘plug in’ port, but it is unlikely that all consumers would take advantage of this feature when they finally got home from a long trip. Furthermore, a Series Hybrid with its smaller batteries requires much less ‘filling up’ when you plug it in; you wouldn’t "need" a 4 hour recharge as the ICE could do it for you if you didn’t want to plug it in or no power source was available.
The Series Hybrid approach works, and works well; eliminating the mechanical drivetrain has sizable benefits, while optimizing an engine for a narrow speed and power range instead of designing an engine that needs to work well from 500 to 5000 rpm means that efficiency (and mileage) can indeed be excellent without compromising performance.
But why specifically Chorus Meschon paired with an Ultracapacitor, instead of any other electric motor? Except for Chorus Meshcon, the state of the art electric motors are of two types. The first type is permanent magnet (also called DC Brushless) designs that are super efficient and very elegant. The problem, as Oak Ridge National Labs discovered when reverse engineering the Prius, is that these motors fail at elevated temperatures, and so cannot be relied upon to work all the time. That is why Toyota and others use "parallel" or "dual" hybrid designs that keep the mechanical drivetrain, and the mechanical linkage from the engine to the wheels.
GM, like Tesla, uses the second type, 3-phase AC induction motors that do not have the same thermal limitations as permanent magnet motors -- but they are oversized because the overload performance requires a larger, heavier, and far more expensive motor and drive electronics. This is where the multi-phase AC induction motor called the Chorus Motor steps in to bridge the gap between the features of both of the other two motors, combining their strengths, but having none of the individual weaknesses that each has.
Up to this point, there has been no electric motor technology that met both the size and heat requirements of automobiles. And short term torque requirements have been the underlying cornerstone for designing the powertrain, which has limited the efficiency and the mileage of standard vehicles. Therefore the next design to hit the mass market and compete in both performance and price will be a Series Hybrid with a Chorus Electric motor and an ultracapacitor (for supplying the higher current needed for the short and occasional ‘burst’ torque) and an average mileage that will fulfill the dream of planners for the past 25 years.
Written by Aaron Bianco - www.ChorusCars.com
Readers have left 8 comments.
No.1 If Ford could do this
Would really like to see Ford do this. Though I guess they will be busy importing cars from their Europe operation.
No.2 If Ford could do it...
I think that Ford and ther other big 3 auto makers need to think about something like this. I dont know the Chorus technology.. but it looks good - even better when using something like an ultracapacitor with it. It's only a matter of time now - as the big 3's days are truly numbered.
No.3 More nimble company could do it
A smaller company could do this because they would be more nimble. The big 6 auto companies are ocean liners that cannot turn that fast.
I agree with all the comments above. It is sad that a country that could get so motivated back in the space race days can't come to the plate and blow the world away with an innovative and efficient design. I own both a Saturn Vue and Toyota Camry Hybrid. The technology in the Toyota makes the Saturn look like a child designed it. I get excited when I read about what could be but realize there is too much tied up in oil when it comes to any support by our government. I truly hope I get to see some of this in real application in my lifetime.
No.5 Something for Nothing?
Surely there is some power loss whilst topping up the Ultracaps from an ICE. Doesn't this drain further reduce the capabilities of the smaller/ less powerful engine?
If the Chorus really does work, why not use it with the diesel engine, there are some out there with great mpg's, but sadly needing that oomf that could be supplied by Ultracaps.
No.6 Love to know more
Methinks that the energy companies have invested downstream into the automotive makers, and thereby have subtle control over what's on the drawing boards. As such, will they sell you a car that's good for you or that's good for them? It will take many individuals to create a groundswell, until a smaller more nimble company as someone pointed out to make it legit'. Would love to find out more about this.
Questions , questions abound for this . How many volts and at what amperage for the battery ?
How many capacitors and which maker and what type were used ? What motors were used , what is their size , what kind of face on the motors , why use two instead of one in the series configuration. What temperatures were experienced during the testing, what was the ambient temperature during testing ? How many amps were drawn by the motors at full acceleration from stop and how many amps at a steady speed of 65 MPH ? How many mechanical HP was the gen set ? Why was a gen set this size chosen over an optimal sized one ?
What are the dimensions of the motor and how much does it weigh ?
What is the cost of the motor and all the controls ?
It sounds great , but much more information has to be available for me to consider it for OEM.
The progression to more efficient transportation models needs to be aware of and accomodate just how much of our infrastructure we can change at a time. I see the progression going as:
This way we aren't throwing away all of the infrastructure we have in gasoline usage, but all NEW infrastructure is in electrical storage, generation and distribution.