Before answering this question, let's talk about our common areas of joint ventures and hybrid power. At present, the main force is two hybrid forms headed by Toyota, which is in the form of planetary gear and has two motors; Honda is simpler and has a higher proportion of electric drive, but the upper limit of driving force depends more on the motor; Ford and GM's hybrid structure did not break away from the planetary gears, and in the early days it was patent evasion. However, according to the current product distribution, such a hybrid structure is difficult to achieve the balance between high fuel efficiency engine and power performance, and good fuel consumption performance often needs to sacrifice a lot of power to achieve.
The two-speed DHT system independently developed by Great Wall Motor has fundamentally solved this problem. The two-speed direct drive condition allows the engine to participate more in the direct drive condition and adapt to a wider range of vehicle speed changes, while keeping the engine in an efficient speed range to ensure the improvement of fuel consumption and power. In addition, the core components of this powertrain design are the self-developed results of Great Wall Motor, which makes it the first car company to break through the technical barriers of joint venture and hybrid.
However, in the face of BYD DM-i's powerful offensive, the Great Wall must find its own way to break through, and it can't win by shifting gears. After all, Geely has come up with a third-gear DHT scheme. Under the heavy pressure, this Hi4 system was born: two-wheel drive changed to four-wheel drive, the fuel consumption was almost unchanged, the terminal price was not affected, and the cost did not increase significantly. This is a brave and innovative attempt.
Of course, this is not magic. It originated from the existing lemon DHT system, and changed the layout of P 1+P3 to P2+P4, forming a four-wheel drive hybrid system with the maximum total power of 340kW, covering A-C vehicles. Including special hybrid engine, DHT gearbox, front axle motor, high-power rear axle motor and low internal resistance power battery, divided into 1.5L+DHT+P4 and 1.5T+DHT+P4.
Compared with the existing lemon mixing system, it replaces P 1 and P3 motors in the front axle with P2 motors, and adds P4 motor in the rear axle, forming a dual-motor structure necessary for strong mixing. In addition, the existing motor technology of Great Wall Group has been accumulated, and both motors can achieve good power and efficiency. At this point, the two-wheel drive has changed to four-wheel drive, the performance has improved, and the conditions of "constant cost" have been met. This system not only saves a motor compared with Toyota's fourth generation THS four-wheel drive version, but also has higher performance.
As for the others, we are more familiar with the fine grinding process of the Great Wall.
The engine has been re-optimized in intake and exhaust efficiency, friction coefficient of internal components, combustion system and thermal management system. The thermal efficiency can reach 4 1.5%, especially the mainstream energy-saving optimization technologies such as 1.5T engine, Miller cycle and VGT variable cross-section turbine, which are all embodied in this engine, and it is difficult to find rivals in joint venture car companies.
The second gear DHT adopts a relatively simple clutch+fixed shaft speed change structure to shift gears. This system evolved from Honda's idea, ensuring lightweight and reliable performance. Working with high fuel efficiency engine can make the speed range of direct drive wider and ensure better power performance on the premise of good fuel consumption. Judging from the effect of the existing powertrain experience, both self-priming and turbine engine matching can take into account the performance of power, fuel consumption and NVH. With the addition of P4 motor, the logic of this gearbox has a broader adjustment idea in daily use links such as fast start, power distribution in corners, rain and snow roads, etc.
In terms of energy consumption management, the newly added rear axle motor can also recover kinetic energy, so the recovery process will be more efficient. Even in extreme cases, when one axle slips, the other axle can recover its energy without changing its face. Of course, the driving style of vehicles has also become more flexible. Theoretically, the corresponding driving modes can be selected according to different road conditions to realize intelligent switching of front drive, rear drive and four-wheel drive. For this Hi4 hybrid system, it also gives the vehicle more driving personality. The four-wheel drive system can improve the passing capacity of vehicles according to different road conditions. In extreme cases, when one shaft slips, the other shaft can still achieve continuous kinetic energy recovery, which is really "light clouds and light winds".
Having said that, you may sound a little brain-burning, but I think it can be simply understood as: this hybrid four-wheel drive system overcomes the dead hole of "strong mixing" to a certain extent, that is, power and fuel consumption cannot be both. Under the condition of traffic jam, it can only use internal combustion engine as charging treasure, just like the mixture of two fields; Under medium and high speed conditions, different transmission ratios of two gears can be adopted to adapt to different speed ranges. When the engine is directly driven, it can also store excess energy and make good use of every drop of fuel.
Of course, according to the official statement, this four-wheel drive system also unlocks more driving scenes and driving pleasure, and can derive different personality adjustments on different levels of vehicles, and combine motors with different powers on the front and rear axles to realize the personality changes of vehicles brought by different driving forms, which provides more possibilities for hybrid vehicles at this stage. From this point of view, Great Wall Motor has indeed grasped the long-term trend and adhered to the long-term corporate creed. This system will be on the bus as soon as next month. Let's look forward to it.
This article comes from HD, the author of Easy Car Number, and the copyright belongs to the author. Please contact the author for any form of reprint. The content only represents the author's point of view and has nothing to do with the car reform.