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Who does the domestic green card plug-in mixed car do fire? BYD Qin PLUS DM-i is bound to be on the list, from March 2021 to the listing of the whole year to sell about 200,000 units, not only bydir's sales king, even in the face of Langyi, Xuanyi and other hot star cars are not afraid.
Geely Emgrand L Hi · X
BYD Qin PLUS DM-i
The popularity of the 120,000-level green card plug-in mixed car has naturally attracted widespread attention from major manufacturers, Geely Automobile took the lead in exerting force, and Emgrand L Hi · X officially debuted in mid-April this year and is expected to be officially listed in the second quarter of this year. Internal and external design, functional configuration of these simple things we do not repeat, today we focus on talking about, Geely Automobile in the Emgrand L Hi · What is the essential difference between the power system of X and BYD Qin PLUS DM-i.
● Engine: "with T" or "self-priming"? That's a problem.
BYD 1.5L: Self-priming, improving compression ratio & thermal efficiency through Atkinson cycle
First of all, let's talk about the Qin PLUS DM-i that we are familiar with, this car is equipped with a BYD Xiaoyun 1.5L self-priming engine (81kW/135Nm), the official through the intake side of the VVT to achieve the Atkinson cycle, the compression ratio increased to 15.5:1, although the operating conditions are narrower than the Alto cycle used in the fuel vehicle, but the victory has a very high thermal efficiency at a stable speed;
At the same time, the engine itself has also been electrified, the left pulley system is canceled, the oil pump, water pump, compressor are electric drives, and the rest are net power, further allowing the engine to "reduce the burden"; to put it bluntly, the kinetic energy generated by gasoline combustion is in addition to the gas distribution system.
Geely 1.5TD: with T, emphasizing the full working condition of large torque output
Let's take a look at the Emgrand L Hi ̇X, although it is not listed, but the current live car at the press conference shows that this car is equipped with a 1.5L inline four-cylinder engine with T. Why is it confirmed to be a four-cylinder? We can look at the intake manifold part in front of the body, which is obviously symmetrical with four air intakes, if it is a three-cylinder, there will be no groove in the middle, which is different from hoshikoshi L Hi · X is noticeably different (blue hybrid, 1.5T three-cylinder machine).
Geely 1.5TD: four intakes = four cylinders
So why is it determined that it is a turbocharged engine with an inverted layout? We can see that the air filter on the right side has a thick pipe directly connected to the inside of the cabin, because the exhaust gas turbocharger is in this position, and the intake air will be wrapped back from the side of the body after being pressurized, and after being cooled by the intercooler, it is poured into the intake manifold, which is a typical reverse layout. If it is an inverted self-priming engine, the intake of air does not need to be so troublesome, and the thick pipe of the air filter will be directly connected to the front intercooling, and then let the engine suck in.
Empty filter tube wrapped around: reverse layout with T
In addition, Geely's official power data can also support our inference, this 1.5TD engine has a maximum power of 181Ps (133kW) and a maximum torque of 290Nm, which is exactly the same as the 1.5T inline four-cylinder engine used in the Binrui COOL fuel version, which is a "fierce" in-line four-cylinder engine tuned.
Geely Bingrui COOL 1.5TD
Geely Emgrand L HiX 1.5TD
The same data also proves that Emgrand L Hi · The 1.5TD engine mounted by X may not have been electrified, and the probability is the common Alto cycle of pure fuel vehicles, with T normal compression ratio of about 10:1, high load conditions will be decompressed through VVT, more emphasis on the efficient power output in the whole scene, the economy of stable working conditions will be worse.
The advantage is that the vehicle power performance is more eye-catching, especially the high-speed working conditions, which Qin PLUS DM-i can't do; and the engine has sufficient power output, and there is basically no battery loss problem in the face of high-speed cruising conditions, and BYD Qin PLUS DM-i has been because the 1.5L engine can't hold the high-speed scene, resulting in a continuous decrease in battery power, and then the power is limited.
● Dual motors: "coaxial" or "dual axis"? The difference is not small.
After talking about the engine, let's look at the "Transmission" section on the right. This is no longer a transmission as we understand it in the traditional sense, but a hybrid scheme that regulates the speed of the vehicle through an electric motor. Moreover, the hybrid modules developed by different technical routes and different manufacturers are also very different.
BYD DM-i and Gilli Thor Hi· X all adopt a dual-motor scheme and eliminate the independent transmission structure, which essentially belongs to the same technical route, but the layout is different, resulting in different characteristics.
BYD EHS: Two circles, dual-axis layout
BYD Qin PLUS DM-i uses the EHS132 or EHS145 electric drive module, the two motors are dual-shaft layout, one and the engine coaxial, the other is placed side by side, the difference in models only means that the external output power of the dual motors is not the same (132kW, 145kW).
This layout is basically the same as the fourth-generation Toyota THS, the advantage is that it can reduce the lateral width of the entire hybrid system, which is more convenient to "tuck" into the car; at the same time, the drive motor is not easy to be disturbed by the engine during the heteroaxial layout, and the efficiency of the pure electric mode (engine stop) is higher.
Geely DHT PRO: One circle, coaxial layout
Geely in Emgrand L Hi · X uses the DHT Pro electric drive module, the engine and the two motors are on the same axis, as if strung together. In addition, refer to the previous Hoshikoshi L Hi · X model, this set of electric drive module can output 100kW / 320Nm of power, the data is worse than BYD EHS132/EHS145, which indicates that the car's power performance in pure electric mode will be slightly behind.
Gilly Hi · X: GM motor + clutch + planetary gear set + TM motor
Compared to the parallel layout, the coaxial layout is not conducive to reducing the horizontal width, which may be the Thor Hi · X is one of the reasons why it does not use a high-power motor. Of course, the benefits of coaxial series are also there, which is related to the electromechanical coupling system below.
● DHT module: Add three physical stops, what is the significance?
There is an engine, indicating that the engine can provide direct or indirect power; there is a motor, indicating that the motor can also provide power; how to integrate the two kinds of power, so that the engine and the motor provide power at the same time, this is what the DHT module is going to do. At this point, BYD DM-i and Geely Hi X uses a different technical route.
Only the clutch, the engine can not be driven directly at low speeds
On the Qin PLUS DM-i, the engine output shaft is not directly connected to the motor, but there is a set of clutches responsible for coupling /decoupling, when the speed exceeds 60km/h, as the clutch is closed, the power output of the engine and the coaxial motor can be coupled with the motor on the other shaft for power/speed coupling, thereby directly providing power to the wheel.
Although this practice is efficient, it also has its limitations, for example, when driving at low speeds, because the engine output shaft is not connected to the variable speed module, the high speed cannot be power-coupled with the motor, and the teeth will be beaten and the engine will be turned off. It is precisely because the engine cannot be kept "on line" at all times, so that the DM-i series generally uses a larger drive motor so that the vehicle can get a relatively sufficient power output in the whole scene.
Gilly Hi · X: Additional planetary gear set to regulate the speed of the system
Gilli Thor Hi · X is another design idea, not only the engine output shaft end of a set of clutches, the engine stop does not affect the motor drive, to achieve electrolytic coupling; in addition, the coaxial layout of the dual motors between the two sets of planetary gears, by TA motor coupling and power shunting.
Because there are three more physical gears, the engine can also intervene at low speeds
So here's the point! When the vehicle is driving at a low speed of about 30km/h, even if the speed output of the engine and GM motor is high, it can be decelerated by different transmission ratios through the planetary gear set, so as to integrate into the power output without fear of damaging the gear;
In addition, in pure electric mode, the TM motor on the right side can also be regulated through the planetary gear set, which can also amplify the torque and reduce the low-speed noise. These two points are not possible for BYD DM-i.
The clutch alone will not do
Back to the question above, why is Geely Hi X Want to use a coaxial dual motor layout? Because the drive motor must pass through the double planetary gear set to carry out complete speed/torque conversion, otherwise the 100kW motor will be more difficult to drive the mass car directly through the reducer.
● Battery pack: blade battery VS ternary lithium battery, who is more suitable?
Finally, we might as well talk about the differences in batteries. Qin PLUS DM-i and Emgrand L Hi · X as a green card plug-in mixed car, are equipped with a large capacity lithium battery, support pure electric mode and external power charging, low pure electric endurance is also 50km +, which is the national policy for green car "hard indicators", but in the battery type, the two are used lithium iron phosphate batteries and ternary lithium batteries.
Blade panels & arrays
At present, all BYD models are blade battery technology, and its essence is still lithium iron phosphate battery, and blade battery is a manufacturing process. Moreover, in different models, the layout of the battery board is also different, pure electric cars are horizontal arrays, and plug-in hybrid cars because of the limited chassis space, are changed to longitudinal arrays, which also makes the encounter with frontal collisions or rear-end collisions, the battery pack pressure resistance is better.
Ternary lithium battery: arranged in a cylindrical array
From the perspective of material cost, lithium iron phosphate batteries in addition to lithium, and not applied to many other precious metals, and ternary lithium batteries to improve energy density need to use nickel, material and process costs are higher; coupled with BYD (Fordy batteries) fully master the whole industry chain of power batteries, high autonomy means low cost, which is not done by peer OEMs.
From the user's point of view, the energy density of lithium iron phosphate batteries is lower, coupled with the upgrading of the packaging process, the safety itself is superior to the ternary lithium battery of the cylindrical battery; in addition, the new process also makes the cycle life of the blade battery higher.
Disadvantages, more sensitive to temperature, high requirements for battery temperature control system. The ternary lithium battery can achieve higher capacity with lighter weight, and is less sensitive to temperature, which is more suitable for the northern region where it is below zero.
summary
In the matter of whether to give up the capital, it is obvious that the Geely Emgrand L Hi · X is still more arrogant, which is not only reflected in the hardware of the engine, electric drive module, and battery pack, but also naturally fed back into the product experience, such as power performance. It's not that the BYD DM-i is inferior to the Gilli Ray's Hygienist Hi. X, the two big guys have different understandings of these two A-class plug-in hybrid cars.
From the user's point of view, higher-level hardware has created emgrand L Hi · The X model 6.9 seconds "breaking the hundred" performance, will also inevitably increase the price of this car, it is expected that the same configuration will be 10,000-20,000 more expensive than the Qin PLUS DM-i, which is also reasonable.
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