○ bird's-eye view shallow reading From thinking to landing, Pi4 platform is the first work. Frankly speaking, the platform landing of the Great Wall is far less than that of Volkswagen and Toyota, and of course, the latecomers also have the advantages of latecomers, such as more divergent ideas and more diverse technologies. Among them, the hybrid system is P+P4, the P end is BSG motor, and P4 is rear axle motor equipped with two-speed reducer. The power can be matched with 2.T and 1.5T engines, and the gearbox is matched with 6DCT, 7DCT and 8AT. These different powers can be flexibly combined. In addition, it also includes different battery packs and motors. This platform can meet all models from compact to medium and large, and it can also be regarded as the first landing of the Great Wall's thinking on platform technology. Five years later, Great Wall has a better understanding of the platform, and more new products and technologies have emerged in both mechanical and electronic aspects, and these new ideas and technologies constitute the brand-new platform of Great Wall Motor that we will talk about below.
○ Main course: The Great Wall is placed horizontally on the platform (lemon), and one platform dominates the world! As a platform called "reborn" by Great Wall Motor, I think the brand-new horizontal platform has three main characteristics, namely, comprehensive vehicle coverage, wide technical coverage and new electronic architecture. (Officially named Lemon Platform, hereinafter referred to as Horizontal Platform)
○ Wide vehicle coverage Let's start with vehicle coverage. This horizontal structure is first of all a load-bearing car body platform, which is very exaggerated and flexible in the malleable design of car body size. This shows that the horizontal platform including cars and MPV models can be satisfied. The tolerance of suspension also illustrates this point again. Although the front suspension is McPherson suspension, the rear suspension has various forms, and one * * * can match three kinds, namely torsion beam, trailing arm two-link and three-link respectively. In terms of power, there are five different forms, among which the pure fuel version includes 2.T and 1.5T. There are three hybrid models, namely 1.5 naturally aspirated, 1.5T and 2.T. At present, the high-power version is still in the late debugging stage, and the mainstream will be the low-power version of 4N2. The biggest feature of the brand-new 4N2 engine is fuel economy and high efficiency. The goal of the new engine at the beginning of research and development is this aspect, with a compression ratio of 12 and a thermal efficiency of 38.3%, which is also a good figure in the current engine field. For more information about this engine, please refer to 2.T with 9-speed dual clutch? Great Wall New Powertrain Analysis)
○ Wide technical coverage If the rich basic module forms can make this platform cover a variety of models, then the integration of various technologies will make this platform have wider extensibility. We often hear such a concept, such as exclusive electric vehicle platform, hybrid vehicle platform, etc. At present, this is a platform specially developed by many car companies for new energy vehicles. The biggest feature of this kind of platform is the tiled chassis design, and at the same time, there is room for the layout of the power system in the front or rear axle. Different car companies seem to be similar. The horizontal hybrid platform is called DHT, and officially named as the special power platform for oil-electric hybrid. For the hybrid platform, we should first pay attention to its hybrid form, and the hybrid form of this platform is very clear: the same car has three modes: direct drive, series and parallel. When working, the system will be distributed among series, direct drive or pure electric according to different working conditions, which is mainly related to the power system of the hybrid platform. The engine has been introduced to you above, and there are three kinds of power systems specially developed for hybrid, and the two-speed reducer is matched with it. In urban areas, it is generally in series mode or pure electric mode, and the engine will be kept in the most economical state to ensure the lowest fuel consumption, and the reducer is also in the first gear state. When entering the suburbs or elevated roads from congested urban roads, although the speed will not be too fast, it may enter a medium-speed cruising state. At this time, the system depends on the speed and driving smoothness, which may be EV mode or series mode of engines in the economic speed range. Once there is a sudden acceleration, the system will directly enter the situation of high power output. At this time, there will be three modes: first, the pure electric mode in which the front and rear motors simultaneously exert force, and in the case of electric four-wheel drive, the maximum power can reach 265kW；; The second is the power output when the engine and the front axle motor are connected in parallel, at which time the reducer is in the first gear state; The third party is also the power output in parallel mode, but at this time, the front and rear axle motors will start. The DHT platform model of the Great Wall hybrid platform will enter the second gear mode at high speed, and the engine will drive directly at the same time. If it accelerates, it will switch to the first gear to output high power with the motor. According to the data of the Great Wall, the new hybrid platform can save 1%-15% more fuel than series hybrid at high speed cruising, and the most important thing is to ensure the high power output of overtaking and other operations. This is the basic situation of the DHT hybrid platform. This hybrid platform mainly pursues economy. If you need better dynamic performance, then the stronger hybrid platform (P2+P4) below may meet your needs. This platform is also an extension of the horizontal platform, but it seems to me more like an upgraded version of the Pi4 high-end car platform introduced earlier. The battery pack has been expanded to adopt lithium-ion batteries, and the capacity can be matched between 12.96kWh and 43kWh. The biggest feature of this architecture is that it emphasizes power, while minimizing energy consumption and ensuring economy. Finally, the pure electric vehicle, the pure electric vehicle platform is still an extension of the horizontal platform. Therefore, the size of the car body is still within the range of the horizontal platform, and its basic modules are also very clear, namely the electric drive axle of the front and rear axles and the power battery unit in the middle. Among them, the front axle electric drive axle has three motor configurations (all permanent magnet synchronous motors), which are 13kW/15kW and 2kW respectively. The rear axle is divided into two versions: double motor and single motor. The single motor has two options of 15kW and 2kW, and the double motor has one option of 2×2kW. Tip: LFP above refers to lithium iron phosphate battery, and NCM refers to ternary lithium battery of Ni-Co-Mn route. CTP belongs to battery cell integration technology, such as BYD blade battery. Among them, Honeycomb Energy has completed the research and development of cobalt-free batteries. Compared with traditional lithium batteries, cobalt-free batteries are not restricted by cobalt, and the cost will be reduced by 1%-15%. However, at present, the technical cost will definitely be high. In addition to the traditional fuel, hybrid and pure electric vehicles, Great Wall Motor's horizontal platform has also made technical reserves for the hydrogen fuel vehicle platform. The vehicle structure of this hydrogen fuel vehicle platform is still unclear at present, but the general framework will be divided into three categories, namely, the fuel cell stack in the front, the power battery in the middle and the hydrogen storage tank in the back. Its driving forms will be divided into two types: two-wheel drive and four-wheel drive, in which the front and rear motors are 2kW. This platform will also be dominated by SUV models, which are currently designated as medium and large vehicles.
○ Electronic architecture The new electronic architecture is an important link that must be considered in the platform now. Its essence is to reserve sufficient upgrade space for advanced driving assistance or more advanced automatic driving. The biggest difficulty lies in the connection of different sensors and the integration of traditional buses. This gave birth to a brand-new concept: domain. Then the corresponding scene is very clear. At low speed, driving assistance under congested road conditions can be completed, including braking at intersections, collision warning between front and rear vehicles, etc. At high speed, adaptive cruising in full speed domain can be completed, and at the same time, it has the function of automatic lane change (integrated into high-precision maps), and at the same time, it can also realize functions such as curve deceleration during automatic cruising. All the above functions will be realized by 222.
○ What are the other features? In addition to the platform technology mentioned above, the new transverse platform has also greatly improved the body structure and manufacturing technology. For example, in the body design, the vehicle has been redesigned for the collision energy transmission route, including the energy absorption ring in the front section, the front sill beam and the upper and lower longitudinal beams with small overlap angle. In addition, a large number of high-strength steels are used in key parts such as A-pillar and B-pillar, and the traditional partial welding is changed into integral stamping (knocker structure) to maximize the lightweight and body stiffness. According to the data of Great Wall Motor, the models with horizontal platforms will be higher than Japanese cars in the same level of lightweight, which is very exciting. If we can really achieve the lightweight level as mentioned in the data, with 9DCT, the fuel consumption of the Great Wall horizontal platform is very exciting.
○ Vertical platform: Compared with the horizontal platform, the 3.T+9AT hard-core off-road architecture full of surprises actually surprised me more. For the domestic off-road circle, the release of the vertical platform can be said to give off-road enthusiasts more choices, and at the same time, it can be seen that Great Wall Motor has made unremitting investment and efforts in off-road. First of all, from the perspective of the core architecture, the brand-new vertical platform has four obvious characteristics: first, it is highly extensible; second, it is also the most important part of the brand-new powertrain, which is what I am looking forward to very much; third, it is reliable; and finally, it is rich in off-road functions. Let's talk about the extensibility of the platform first. The horizontal platform above can be described as a platform that "sweeps the world", while the vertical platform does not give up. The active stabilizer bar also appears in the configuration list. By disconnecting the left and right wheels, the restraint of the wheels on both sides of the same axis is reduced. This technology can increase the suspension stroke of this platform model by at least 3mm, so that the wheels can contact the ground to the maximum extent. In the end, different suspension forms will correspond to different off-road vehicles. Generally speaking, the Great Wall vertical platform provides 425 basic modules in chassis, body, power and electronics, among which 38 basic modules are used as the skeleton, and finally engineers will complete the development of different models according to the skeleton.
○ The unexpected power configuration power aspect is the most surprising place for me in this vertical platform. This time, the vertical platform will have two technical routes of fuel and hybrid vehicles, among which the pure fuel vehicle will use three powertrains, namely, 2.T (18 kW/38 N m), 3.T (26 kW/5 N m) and 2.4T (135 kW/48 N m diesel), and the hybrid (two routes of PHEV and HEV) is also 2. At that time, the engine used technologies such as in-cylinder direct injection, dual turbocharging, dual VVT variable valve timing and variable displacement oil pump, with a maximum power of 22kW and a maximum torque of 48 N m. This time, the 3.T engine released on the vertical platform upgraded the technology again, and the turbocharger became a variable cross-section supercharger with double injection, and finally the dynamic performance of 26 kW/5 N m was obtained. The official thermal efficiency of the 3.T engine used in hybrid vehicles will reach 42%, which is also dual-injection and dual-variable turbine geometry, and adopts Miller cycle at the same time, but the specific effect needs to be tested in actual loading. The new 9AT gearbox still comes from Gerhard, chief engineer of Honeycomb Yichuang Transmission System? Mr Henning's hand, as the developer of Mercedes-Benz 9AT, the 9AT of Great Wall can be regarded as a work standing on the shoulders of giants, which also expands the hybrid module. At the same time, the dense gear ratio of 9 gears will inevitably bring better fuel economy performance, and the automatic transmission of hydraulic torque converter can also bear higher torque input and output. At this point, the layout of the Great Wall in the transmission system has gradually become clear. The horizontal platform has 9DCT and 7DCT with lower torque capacity but better economy and efficiency, while the vertical platform has 9AT with higher torque. At the same time, both 9DCT and 9AT support the expansion of hybrid module and four-wheel drive, which will form the matrix of the future Great Wall transmission system. After talking about extensibility and power, let's finally look at the off-road configuration. I think the new vertical platform is a combination of Prado and herdsman in off-road configuration, and also combines Land Rover's all-terrain feedback system. Whether you are a white or a deep off-road user, you can find a car configuration that suits you. First, let's look at the four-wheel drive. The new platform is equipped with part-time 4wd system, the front and rear axles are allowed to be hard connected, and the power distribution can be 5:5. At the same time, it is also equipped with three locks, namely, the front axle electronically controlled mechanical differential lock, the central differential lock of the central transfer box and the rear axle mechanical differential lock. These three locks can be controlled independently. In daily use, the four-wheel drive system is controlled by computer by default, and the terrain is in the state of automatic recognition, and the system will automatically switch the all-terrain system. If you enter the complex off-road terrain, you can enter the expert mode. At this time, the terrain information is carefully distinguished, such as sediment or gravel, and the system will control the four-wheel drive system more accurately. For the more complex road conditions, you can manually choose the off-road crawling mode, at which the vehicle speed crawls forward, and the driver can free his feet and concentrate on driving. What you have to do is to avoid obstacles and find the optimal path. This mode allows the driver to focus more on driving. In addition to these off-road technologies, many unique technologies have been added to the vertical platform to improve the driving safety and electronics. For example, a radar is installed in the rear view angle to measure the height of the water surface in front, so as to judge the wading depth and help the driver to drive in the water. In addition, the electronic architecture of the whole vehicle is basically similar to that of the horizontal platform, and it is also the architecture of gateway+domain controller. At the same time, there is room for upgrading the advanced driving assistance function and future automatic driving, and the software can realize FOTA iterative upgrade. At the same time, the active driving system is similar to the horizontal platform, so I will not repeat it here. Summary: In my opinion, the horizontal and vertical platforms released by the Great Wall this time are very courageous. First, the horizontal platform combines hybrid, pure electric and hydrogen fuel cells, and the models range from Class A to Class D. For the development of multi-technology power technology on the same platform, this brings great challenges to the universality of parts, because the advantage of the same platform lies in the universality of traditional parts, so that the costs can be shared equally, including mold development, etc. However, the cost of the same platform with such a large span needs to be observed later. Second, from the platform point of view, Great Wall Motor may tilt towards hybrid in the future, especially plug-in hybrid and HEV. Thirdly, the vertical platform has completed the integration of non-load-bearing vehicles, and 3.T+9AT will bring stronger competitiveness. At the same time, hard