Electric-driving transmission device for electric vehicle and control method

Abstract

The invention relates to an electric-driving transmission device for an electric vehicle and a control method. The electric-driving transmission device comprises a driving motor, a differential mechanism, a first brake, a second brake, a first planetary gear set and a second planetary gear set, wherein the first planetary gear set comprises a first sun wheel, a first planet carrier and a first gear ring, and the second planetary gear set comprises a second sun wheel, a second planet carrier and a second gear ring. An output shaft of a driving motor is sequentially connected with the first sunwheel and the second sun wheel. The first gear ring is connected with the first brake, and the second gear ring is connected with the second brake. The first planet carrier and the second gear ring are connected to form a whole, the second planet carrier is provided with an output support, and the output support is connected with an input shaft of the differential mechanism. Compared with the prior art, the electric-driving transmission device can achieve non power failure in the gear shifting process, is low in control complexity, has relatively low requirements for performance of the drivingmotor, and is high in practicability, compact in structure, small in size, low in weight and low in manufacturing cost.

Description

technical field [0001] The invention relates to the technical field of electric vehicle transmission, in particular to an electric drive transmission device and a control method for electric vehicles. Background technique [0002] At present, most of the pure electric vehicles on the market use a single-stage reduction mechanism without gears, and the motor completes the task of shifting. Although its structure is simple and the cost is low, it cannot take into account the power and economy of pure electric vehicles. According to the motor Characteristic curve, gearless deceleration is difficult to keep the drive motor working in the high-efficiency range, which reduces the efficiency of the electric drive assembly system. Especially in the low-load conditions of starting and maximum speed, the motor is in the low-efficiency zone, which seriously affects the life and endurance of the battery. [0003] In the patent with the publication number CN207333612U, a two-speed elect...

AI Technical Summary

Problems solved by technology

[0002] At present, most of the pure electric vehicles on the market use a single-stage reduction mechanism without gears, and the motor completes the task of shifting. Although its structure is simple and the cost is low, it cannot take into account the power and economy of pure electric vehicles. According to the motor Characteristic curve, gearless deceleration is difficult to keep the drive motor working in the high-efficiency range, which reduces the efficiency of the electric drive assembly system

Especially in the low-load conditions of starting and maximum speed, the motor is in the low-efficiency zone, which seriously affects the life and endurance of the battery

[0003] In the patent with the publication number CN207333612U, a two-speed electric drive system for pure electric vehicles is disclosed. In this invention, there are two-speed output gears on the intermediate shaft assembly, which are arranged on both sides of the synchronizer and vacantly sleeved on the input shaft. The shifting function is realized by the electric shifting unit and the synchronizer, and the structure is simple, but the parallel shaft transmission design needs to switch gears during the shifting process, and there is power interruption, which reduces the driving quality of the vehicle

Images