What is the development trend of transmission in the era of new energy vehicles
with the successive announcement of the timetable for banning the sale of fuel vehicles in various countries around the world, as well as the comprehensive efforts of major car companies in the field of new energy vehicles, new energy vehicles ushered in a major outbreak in 2018
from the data of new energy vehicles in September released by the China Automobile Association, the production and sales of new energy vehicles in September increased steadily, with a total sales of 121000 vehicles, a month on month increase of 19.8% and a year-on-year increase of 54.8%. Compared with the year-on-year decline in China's auto sales in September, new energy vehicles were called "upstream" on February 17 just 10 days ago
as new energy vehicles continue to increase their market share, they also bring about changes and progress in automotive technology. The arrival of new technology will inevitably lead to the regression or even disappearance of some traditional technologies, with the PE deficit of 3.4 million tons in India in 2023. Then, does the rapid development of new energy vehicles also mean that the era of the end of fuel vehicles is coming? This article will explore the truth through the transmission, one of the three major parts of the automobile
transmission is not so important to pure electric vehicles
transmission is one of the core components of traditional fuel vehicles. It has two basic functions: one is to cooperate with the clutch to ensure that the vehicle starts normally and will not stall due to excessive starting load; Second, in the process of vehicle owners' changing vehicle speed, the engine can be stabilized at the working speed through gear switching (gear ratio). It has a crucial impact on the driving experience of cars, but in the field of new energy vehicles, the transmission seems to be less important. Because the above contents of the electric vehicle motor have a low probability of damage, it can rely on its own perfect system to make the vehicle run normally, and the effect of the transmission on improving driveability is limited. If another transmission is added, the vehicle weight will be increased and the cost will be increased
at present, most pure electric vehicles in China have no transmission in the physical sense. Many people may see the gear handle of some cars and the gear display on the instrument, but in fact, those are analog gears that cater to consumers. The motor itself can work stably at all speeds without the assistance of the gear transmission mechanism
pure electric vehicles on the market are basically single speed transmissions, such as Tesla, BMW I3, BAIC electric vehicle, Qichen CHENFENG, BYD E5, Dihao EV, Tengshi, etc. The advantages are: low cost, simple structure, easy installation, small failure rate, small power loss and small volume. The disadvantage is that when the speed of electric vehicles reaches the limit, there is no room to improve, so the speed of electric vehicles is restricted, and the high-speed economy is not high. Under the condition of the same fixed power, the speed of the electric vehicle with asynchronous motor is faster, but the speed does not increase after matching with the fixed gear ratio transmission. Even Tesla, which has strong acceleration, has poor acceleration performance in the middle and rear sections, which is affected by the fixed gear ratio transmission
in addition, pure electric vehicles cannot be equipped with ordinary transmissions, mainly because the volume and weight of ordinary transmissions are too large compared with electric vehicles. Originally, the battery pack takes up the entire chassis space, and there is not much room for placement at all; Secondly, the transmission efficiency is not high enough! Taking the double clutch transmission with high transmission efficiency as an example, the actual transmission efficiency is about 87%, which means that the original battery pack's range of 100 kilometers is only 87 kilometers after being transferred to the wheels. At the same time, considering the weight of the transmission, the actual mileage may also be reduced
the function of the electric motor is much simpler and more powerful than that of the fuel engine. Electric vehicles can run normally without a transmission, so why increase the cost and add a transmission
development trend of transmission
Gaishi automobile believes that by 2030, electric vehicles will account for more than 80% of China's automobile production. Hybrid electric vehicles will still be equipped with at, DCT and ECVT; In the short term, the mainstream of pure electric vehicles is the reducer, and the trend is the two-stage transmission. For hybrid power, transmission is still the core component. Hybrid cars at and DCT can be carried, but they need special transformation. ECVT has simple structure, high transmission efficiency and good comfort. It can be predicted that after the expiration of patent protection, the market share of ECVT will increase significantly. The front and rear scheme of DCT main drive is highly feasible in the short term, and the long-term trend is the BSG + DCT odd axis motor structure with a high degree of integration. For pure electric, two-stage transmission is the trend. In the short term, due to technical reasons, almost all transmissions of pure electric vehicles on the market are single-stage reducers. In the long term, the two-stage transmission can better improve motor efficiency and high-speed performance, which will become a trend
many insiders who recognize that the secondary transmission will be the future development trend also believe that the use of the secondary transmission can make the motor work more in the high-efficiency area. The reason is that when the secondary transmission is used, the working torque of the motor is much smaller than that of the fixed gear reducer, which reduces the working current of the motor, reduces the burning loss of the motor, and improves the working efficiency of the motor
some insiders also believe that for vehicles with pure electric testing machine to record the force required to tear along the long axis, in order to improve the traditional ratio and realize the increase of the maximum speed and maximum climbing slope, the transmission can be improved, and the five speed transmission can improve the performance of the vehicle. At this stage, the five speed transmission has achieved industrial development, while the research and development achievements of the two speed transmission are obviously not obvious. Therefore, the five speed transmission can directly apply the existing technology and achievements to reduce the research and development cost. At the same time, the five speed transmission has low requirements for batteries and motors, which may be the main direction of the development of electric vehicles in the future
at the 2018 CTI forum, Wang Kejian, President of Beijing Great Wall Huaguan automotive technology, said that the electric sports car K50 has an electric engine and a single speed transmission on each axle. It can provide the performance of only 4.6 seconds for 100 km acceleration and 420 km endurance. The lightweight of the car body (about 800 kg) is attributed to carbon fiber materials. Plastic materials will replace carbon fiber in the next generation of vehicles. The next generation of electric vehicles will have a two-stage transmission. AMT scheme will become the first choice. In the future, multi speed transmission with planetary gear set will also be considered for electric vehicles
Gerhard Henning, the technical director of honeycomb Yichuang Technology Co., Ltd., believes that by 2030, 70% of the 120million vehicles produced worldwide will be hybrid or become pure electric vehicles. However, 70% of vehicles will still have internal combustion engines as part of their powertrain. The 7-speed DCT system provides flexible application possibilities (platform design) for traditional (FWD, AWD) and hybrid (P2, P4) models. When the maximum speed exceeds 160 km/h, a two speed gearbox is required. The two speed electric shaft is equipped with a planetary gear set and a power conversion assembly to avoid traction interruption. Electric drive (single speed) is used for 35, 120, 170 kW peak motors. The automotive industry must be prepared for every possible technology in the future. The future certainly does not belong to battery driven electric vehicles
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