[YesAuto technology] For current electric vehicles, the characteristics of the electric motor determine that it only needs to be equipped with a single-stage reducer to complete the power transmission, and it has achieved good results. However, human desires are always endless. In the research on electric motors, German parts giant Bosch believes that the economy and reliability of electric vehicles can be further increased by adding gears to the transmission system. So perhaps in the near future, electric Car owners will also take pleasure in “comparing” each other with the number of gears in their respective cars.
Regardless of whether traditional car manufacturers are willing to admit, the fact that electric vehicles are becoming more and more popular is something they are very reluctant to face. Since the invention of the diesel locomotive, traditional car manufacturers have invested the most energy and money, and have accumulated the deepest technological accumulation. They are probably the two major systems of power and transmission. However, the current electric vehicles in the market have abandoned these two parts. Because the electric motor has a wide range of speed, it only needs to adjust the input current to complete the control of its power output, so as to realize the acceleration or deceleration of the vehicle, and can adapt to almost all driving conditions. Therefore, in terms of transmission, most of the current electric vehicles only need to be equipped with a single-stage reducer to complete the power transmission from the motor to the wheel through the half shaft.
However, although current electric vehicles can run normally with a single-stage reducer, there are still shortcomings in the single-stage reducer. When the vehicle is running at high speed, the motor needs to maintain a very high speed, which is detrimental to noise control and cruising range; and if a multi-stage reducer is used, the speed ratio range can be increased, and the speed ratio can be changed according to different working conditions. It can have a better acceleration level when the vehicle starts, and reduce the engine speed at high speeds, thereby reducing noise and electrical energy consumption. Bosch has seen this advantage of the multi-stage reducer and has started to develop a multi-speed “gearbox” for electric motors, which is expected to be launched in the near future.
Electric vehicles have no gears. This seems to have become a common understanding of electric vehicles, but Bosch’s latest products are about to break this view. When there is no revolutionary breakthrough in battery technology, multi-speed reducers are indeed useful for electric vehicles. The performance and economy have a positive effect. However, Bosch has not disclosed the core structure of the reducer, whether it uses a planetary gear structure similar to AT, or dual-clutch, CVT, is still unknown, only the waiting time will reveal the secret for us.