This is actually quite normal. With the development of new energy technology, the performance of batteries and motors has been continuously improved, giving major manufacturers more ways to play. Now all major automobile companies are promoting PHEV models. As a pioneer of plug-in hybrid technology, it is not surprising that BYD wants to go further.
Last night, BYD officially announced that it would launch DM-i super hybrid technology featuring "ultra-low fuel consumption" and exposed some parameters and infrastructure. However, key technical information is not yet available. Seeing that everyone's attention is relatively high, Che Jujun tried to explain it to everyone from a technical point of view.
First, the fourth generation DM technology "steering"
Byd DM technology has been developed for more than ten years. The earliest generation was launched in 2008. Since the second generation of 20 13, the main structure of BYD DM technology has been basically laid, that is, the dual-clutch gearbox is used as the power shunt device, through which the engine and motor carry out power shunt.
The biggest feature of BYD's system is that the power is really strong, which is divided into EV mode and HEV mode. In EV mode, it is driven by two motors, while in HEV mode, the engine and two motors can work together. Different from the HEV architecture of Toyota Honda, the HEV mode of BYD's system can directly superimpose the power of three power sources, which is so simple and rude. For example, the comprehensive power of DM in Korea can reach 32 1kW, the comprehensive torque of the system is 650n·m, and the acceleration time of 0- 100km/h is 4.7 seconds, while the comprehensive power of Camry is only 160kW.
If it is pure absolute power, BYD has no rivals in its class. The 100 km acceleration of 20 15 Tang DM has reached 4.5 seconds, which is not even close to the same level.
In the car industry, "fast" is actually a very "valuable" indicator. For example, the difference between Magotan 280 and 330 versions is 33,000, while the difference between 330 and 380 versions is 30,000. The main difference is that the latter is faster and more powerful.
However, the disadvantage of BYD's DM system is that whether it is a dual-engine four-wheel drive or a three-engine four-wheel drive, it depends on the motor, that is, it needs enough power. Once the power is insufficient, the power performance of BYD DM models will be greatly reduced, and the fuel consumption is not as good as that of pure fuel vehicles of the same class.
Users who buy PHEV models are often inconvenient to charge. If they have their own independent charging piles by default, they often choose Model directly. Pure electric vehicle, because the pure electric vehicle has a longer cruising range, good performance, simple system, low failure rate and lower vehicle cost.
So a problem arises: the "fast" of pure fuel vehicles is valuable, and the "fast" of pure electric vehicles is also valuable, but the "fast" of BYD DM system is worthless. Tang DM can run for 5 seconds as early as 5 years ago, but it can't be sold at all.
This is actually not only the trouble of BYD, but also the trouble of all car companies that push PHEV models. On the one hand, they want to push PHEV models to get new energy points, and of course, they also want to do well in performance. On the other hand, many users will buy back PHEV models when using pure fuel vehicles. How exciting the performance advertised by manufacturers is, the chances of users using it are not great. The ultra-low fuel consumption promoted by PHEV models is often sneered at by users, because it costs more fuel than pure fuel vehicles in the state of fuel intake.
Therefore, since the beginning of this year, car companies that have gradually touched the "doorway" have changed their mouths. For example, GAC New Energy began to promote its PHEV model, which saves fuel and does not need to be recharged. SAIC eMG？ It is advertised that the fuel consumption can reach 3.9L/ 100km when B enters the oil.
BYD chose to launch DM-i system, which actually catered to this demand to some extent. It is aimed at users who need new energy licenses but have poor charging conditions. From a performance-oriented system to an economic-oriented system, BYD has made great determination.
Second, the DM-i super hybrid system looks beautiful.
However, unlike SAIC and GAC, BYD's new system is completely different from the previous structure, and it can even be said that earth-shaking changes have taken place.
Let's take a look at the official information released by BYD. The new system consists of a brand-new 1.5L naturally aspirated engine, an E-CVT gearbox and a high-capacity battery. Wait, as I said before, BYD's DM system uses a dual-clutch gearbox, not a physical gearbox, as a power shunt device. The same is true of other mainstream PHEV manufacturers, such as Geely and Volkswagen.
The DM-i hybrid system took another road, using E-CVT as the power shunt device. In fact, E-CVT has nothing to do with mechanical CVT gearbox. Although Toyota and Honda have different control methods for E-CVT, in general, it is used as a power distributor. It has no physical gear, but determines when to use electricity, when to use oil, when to use oil and electricity together, and what is the ratio by adjusting the speed of the engine and motor.
Its advantage is obvious, that is, as long as it is well controlled in theory, the distribution of oil and electricity can be scientific enough to realize energy saving to the greatest extent. The disadvantage is that the thinking is simple, but the control is very complicated. It's too complicated. Toyota has published many patents, but almost no manufacturers have followed up, because it is difficult to achieve similar results. Therefore, BYD suddenly "became a monk halfway" to build an architecture with E-CVT as the power shunt device, which has no experience accumulated. Honestly, it's not good.
In order to achieve better fuel consumption, BYD developed 1.5L naturally aspirated Atkinson engine.
At present, the engine with the highest mass production efficiency is Mazda's compression ignition engine with a thermal efficiency of 43%, followed by Toyota Camry's 2.5L Atkinson engine with a thermal efficiency of 4 1%. Turbocharged engine is better than Nissan's 2.0T variable compression ratio engine, which can only achieve 39%.
In other words, even in the era of the development of turbines, naturally aspirated engines still have certain advantages in pure thermal efficiency. Of course, a bunch of domestic engines with excellent thermal efficiency have emerged this year. For example, Dongfeng claims that the thermal efficiency reaches 42%, and GAC claims that the thermal efficiency reaches 43%. These two engines are also 1.5T turbocharged engines. I won't comment until the actual mass production.
Atkinson cycle, that is, the combustion mode in which the compression ratio is less than the expansion ratio, has been repeatedly proved in two fields, which can really improve the efficiency of the engine, but it will be worse in performance, especially in low-speed torque. However, there are few working conditions of hybrid engine at low speed, and the vehicle is mainly driven by motor at low speed, so this is not a problem.
Therefore, BYD chose to make a 1.5L naturally aspirated Atkinson engine, which is really easy to achieve higher efficiency in theory.
Let's compare this special plug-in engine announced by BYD. Compared with the Honda hybrid engine with the same 1.5L, the compression ratio is higher, and the power and torque are slightly better. Compared with Toyota's 1.8L hybrid engine, its performance is not inferior. The thermal efficiency reaches an astonishing 43%, which is the same as Mazda compression ignition engine. The official claims that the comprehensive fuel consumption of the new model can be controlled within 4L/ 100km.
According to the information disclosed by BYD before, the economical DM system will be installed on Qin DM and Song DM. Even the relatively small Qin Dynasty, its area is equivalent to that of Lingpai. In other words, the overall efficiency of BYD system will be higher than that of Tian Liang, which has been doing it for more than ten or twenty years.
3. What are the problems in DM-I system?
In Che Jujun's view, the biggest problem with this system is that it is too "perfect". According to BYD's previous statement about DM-i, they don't intend to build a dual-domain HEV architecture. Because the battery under the HEV frame is too small, it can't support the pure electric operation of the vehicle for a long time.
If BYD chooses to become PHEV, it must give full play to the advantages of large-capacity batteries. That is to give full play to the advantages of the motor, its performance is stronger than that of the dual-field HEV model, and now it is announced that the fuel consumption is lower and the efficiency is higher, and it is simply occupied at both ends.
Moreover, BYD also said that the cost of DM-i model is lower, only 20,000 more than the fuel version. And the existing Qin Qin? DM is more than 50 thousand more expensive than the fuel version. The basis for PHEV models to enjoy national policy subsidies is that the cruising range of pure electric vehicles should reach at least 50km, and the higher the better, so as not to save the battery cost close to 1 10,000. Although the dual clutch gearbox is cancelled, it is very difficult to control the cost by adding the E-CVT gearbox, plus the motor and control system.
For example, Honda has just mass-produced the 1.5L hybrid system, and the price of the hybrid version is 40,000 yuan higher than that of the fuel version. Toyota has made some concessions on the hybrid assembly of A-class cars, but the difference is still around 20,000 yuan. Both batteries are very small, and the cost is about two thousand yuan.
As for its brand-new engine, it is completely incredible. First of all, it adopts an ultra-high compression ratio of 15.5: 1 All car companies know that increasing the compression ratio can improve the efficiency of the engine. Why don't they do this? Because after the compression ratio increases, the knock will increase and the engine will run unsteadily, but it will not achieve the desired effect.
Mazda has made great efforts to develop a set of spark plug ignition control compression ignition technology, which sounds like a bypass and the actual control is more complicated, but it only increases the compression ratio to 15: 1 at the expense of adding 95# gasoline. BYD has surpassed it lightly, and according to official information, BYD's new engine does not use any new technology. Atkinson cycle+high rolling inlet+cooled EGR is actually a common solution in the market.
And BYD itself has a 1.5L self-priming engine. Now it is equipped on Qin Pro, and its performance in all aspects is just mediocre. Because BYD's focus is no longer on the self-priming engine, and it has not been studying and improving the performance of the self-priming engine like Mazda. It is really incredible that such a "big move" suddenly broke out. It will be super early. What are you waiting for after all these years?
This DM-i probability is a new concept created by BYD, just like the IGBT technology and high-performance silicon carbide module that BYD has been crazy about before. After a long time, the stock price was fired and the result was nothing. Che Jujun will count the insured amount of new cars every month. There is often a big gap between BYD's official sales and insurance coverage. However, many users feedback that they can't get a car, and the supply is in short supply. I really don't understand where BYD's cars have been sold.
The actual situation is unknown. But one thing has to be said, no matter how the manufacturers publicize it, everyone should take the quality of the final mass-produced products as the judging standard, and the products are so good that consumers support them with real money.
Jeju tubercle
Judging from the information disclosed by BYD, its first-generation DM-i system is stronger than Toyota and Honda, and it is all-round. Better performance, lower fuel consumption and lower cost.
If it comes true, you can spend 6.5438+10,000 yuan to buy a hybrid version of Qin Pro. Its performance is better than that of Leiling double engine. It can be used as a pure electric vehicle, and the fuel consumption can be controlled within 4L/ 100km in the case of power loss, and a green license plate can be obtained. This is not just a big killer, it will directly become the "terminator" of the existing A-class automobile market.
However, according to BYD's historical performance, Che Jujun believes that there is a lot of water. Starting from zero to 10 1 is unreasonable. Che Jujun is skeptical about these data.
However, if BYD really makes it, Che Jujun is also happy to be hit in the face and make it all come true. It will always be a blessing for our consumers to have more truly powerful models on the market.
This article comes from car home, the author of the car manufacturer, and does not represent car home's position.