Now there are more and more nouns, all called "CVT", but E-CVT and our impression of CVT driven by steel belt, in fact, has nothing to do with it.
Can't find fish inside the fish fragrant meat shreds? That's pretty much what it means.
E-CVT and CVT are actually completely irrelevant
First, figure out why CVT and E-CVT are so named.
"CVT" is an abbreviation, the full name of the word translated down is called "stepless transmission", English I will not read.
The E-CVT is an electronic stepless transmission, not an extra motor on a traditional steel belt CVT gearbox, and then an electronic control system.
The meaning of the CVT in the name itself is called "stepless variable speed", and the ability to change the speed of the stepless speed can be called "CVT", which does not represent how the structure is.
It's like: we often hear "AT", AT is actually the meaning of automatic transmission, Auto Transmission, including all automatic transmissions.
When chatting every day, it is generally said that 6AT, 8AT, is this the case, right? But how exactly it's structured, you can't mix it up.
Therefore, in layman's terms, "E-CVT" is a very general name, which can be regarded as a system, and hybrid models use this system to achieve the cooperation of engine, battery and motor.
For example: the official website of Toyota Camry Hybrid writes the E-CVT electronic stepless variable speed system, and the Honda Accord Hybrid also writes E-CVT, in fact, the principle of the two is very different, the difference is very large, both called "E-CVT".
Planetary gear sets for Toyota and Ford
First, let's talk about Toyota's E-CVT, which mainly uses a set of planetary gear sets to achieve hybridization.
Zheng Changshun, School of Mechanical and Power Engineering, Shanghai Jiao Tong University, published a paper in the journal "Transmission Technology", "A Brief Analysis of Mainstream E-CVT Power Shunt Hybrid Transmission", which said.
There is a description of the principle of toyota THS hybrid system, the planetary gear set connects the engine, 2 motors and wheels, can distribute the power from the engine and motor to achieve efficient driving of the vehicle.
The planetary gear set is a bit like the finance in the company, which project to allocate funds, which project to reduce expenses, he is here to help you distinguish.
"Hey" this does not add money to the box lunch, add to the welfare fee for everyone to buy skins, and he will do this thing.
For example, the battery power is relatively sufficient, the engine is turned off and rested, and only the motor is used to output power.
But if the electricity is not enough, then the engine also follows, pushing the planetary gear set, it can charge the battery while using the motor to drive the vehicle forward.
The specific working conditions are much more complicated than what I just said, so I will briefly talk about it here.
Since the planetary gear set is irreplaceable in this system, Toyota directly registered this patent, and there are fewer car companies on the market that use this program.
Otherwise, you're going to pay it, and even people won't allow it, right? Only Toyota and Ford are doing this thing.
Honda's E-CVT structure is relatively simple
Honda has always been engaged in technology, you do this, I want to be different from you, right? It can only be different.
Honda's E-CVT is very different from Toyota in principle.
Toyota's planetary gear set is still a bit of a traditional transmission shadow, or taste, Honda's E-CVT structure is simpler.
Zhang Hongyu published a paper in the journal "Automobile Maintenance and Repair", "Honda Hybrid System Technical Analysis", which describes the principle of Honda's i-MMD hybrid system.
In this system, the engine is directly connected to the wheel and the generator, and then the generator is connected to the battery and the drive motor, and there is a clutch between the engine and the wheels.
In most non-high-speed conditions, the clutch is disconnected, that is, the engine only charges the battery, and the motor takes the car to run.
It's a bit like the ideal, it's an extender drive system, you just have to remember this, the front doesn't matter.
Only at high speed cruising will the clutch be combined, and the power is provided directly by the engine.
To use an analogy: Honda's system, the motor is like the secretary of the engine, most of the time it is the secretary to do this thing.
Only the motor of this secretariat can not manage the thing, just look for the boss, look at the high speed can not run, the motor is not very electric, the boss to help, the engine will come, almost such a thing.
The solution ideas of domestic car companies are similar to those of Honda
Not only Honda, but also the E-CVT of many domestic car companies is also such a problem-solving idea.
For example, BYD's DM-i super hybrid and the Great Wall's lemon DHT hybrid system are only driven by electric motors in most of the urban areas, and the engine is to charge the battery.
Only when driving at high speeds, the engine will be directly involved in the vehicle drive, so the daily city transportation, they drive more like a tram, is relatively brisk.
And according to the description of the lemon DHT hybrid system on the official website of the Great Wall, when the high-speed engine is driven directly, it can switch between the two gears of power and economy.
Just like the manual transmission, it can "downshift" the overtaking, which is a little more functional than Honda's system.
Basically it doesn't matter
So, in general, the E-CVT of the hybrid car and the CVT transmission of the traditional fuel car are basically irrelevant, but the name is used to indicate that they have the ability to change the speed stepless speed.
And because each implementation is different, E-CVT is more like a general term for a hybrid system, not necessarily referring to the gearbox structure.
What things I learned after I bought a hybrid
The E-CVT structure used in hybrid models is relatively new, how does it feel to drive?
Now that there are more and more hybrid cars on the street, what are the things that are possible to know after buying and driving hybrid vehicles?
It is said that hybrid vehicles save money, as long as 2 cents per kilometer, is it the most economical and economical choice for families to buy hybrid vehicles?
There are also many brands, Toyota, Honda, which one is strong? Right? There are also many domestic ones, and these materials are ready for everyone.
Keyword: hybrid
Want to see is very simple, pay attention to the WeChat public account "spare tire car", reply to the keyword "hybrid" on it.
My public account, every day will give you a piece of car practical small dry goods, text, audio, video have, pick your favorite version on it, "spare tire said car" waiting for you to play Oh.
bibliography
Zheng Changshun. A brief analysis of mainstream E-CVT power shunt hybrid transmission[J].Transmission Technology,2016.
ZHANG Hongyu. Technical analysis of Honda vehicle hybrid system[J].Automotive Maintenance and Repair, 2020.
[3] Toyota official website
[4] Guangqi Honda official website
[5] Great Wall Motor's official website