Electric Vehicle Two-Speed Transmission Hydraulic Clutch Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electric vehicle driving systems face inefficiencies at both low and high speeds due to mismatched torque and speed characteristics, leading to poor acceleration, high power consumption, and reduced cruising range, especially in complex road conditions.
Innovation Solution
A driving system for electric vehicles comprising a driving motor, a transmission with a first and second transmission unit, and a hydraulic system that engages and disengages clutches to adjust transmission ratios, allowing for appropriate matching of torque and speed characteristics, including two forward gears and a reverse gear, to optimize power transmission efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If a reducer with a large output torque is designed, then the torque transmission capability is improved, but the efficiency increases slowly with speed and power consumption is high at high speed
Solution Approach 1:
The patent applies a two-speed transmission system that dynamically switches between a first speed (low speed gear) and a second speed (high speed gear) based on operating conditions. This allows the system to adapt the transmission ratio to match the driving motor's efficiency characteristics at different speeds, resolving the contradiction between torque capability and power consumption.
Solution Approach 2:
The system changes the transmission ratio parameter by switching between two distinct gear ratios. The first transmission unit provides a larger transmission ratio for high torque at low speeds, while the second transmission unit provides a smaller transmission ratio for efficient operation at high speeds, thus optimizing both torque and energy consumption across different operating ranges.
2Speed
If a reducer with a high speed is designed, then the efficiency increases fast with speed, but the torque transmitted to wheels is too low for starting or climbing
Solution Approach 1:
The system dynamically selects between two transmission ratios based on speed and torque requirements. At low speeds during starting or climbing, the first transmission unit with larger ratio provides sufficient torque. At high speeds, the second transmission unit with smaller ratio maintains efficient operation, thus resolving the contradiction between speed and torque transmission.
Solution Approach 2:
The transmission system is segmented into two distinct transmission units: a first transmission unit optimized for low-speed high-torque operation, and a second transmission unit optimized for high-speed efficient operation. This segmentation allows each unit to specialize in specific operating ranges, resolving the contradiction between speed and torque capabilities.
3Device complexity
If a constant transmission ratio is used, then the structure is simple, but the driving motor efficiency is low at both low and high speeds under complicated road conditions
Solution Approach 1:
The system transitions from a static constant transmission ratio to a dynamic two-speed transmission system. The control mechanism switches between first and second transmission units based on operating conditions, allowing the driving motor to operate in its high-efficiency range across both low and high speed conditions, thus improving energy efficiency while maintaining reasonable structural complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system effectively improves the efficiency of the driving motor under various conditions, reduces energy consumption, and increases the cruising range of electric vehicles by matching torque and speed characteristics, enabling efficient operation at both low and high speeds.
Implementation Method 1
a hydraulic system, which is connected with the first clutch to engage and disengage the first clutch and be connected with the second clutch to engage and disengage the second clutch
Data Source
Figure 1
Figure 2
AI summary
A driving system of an electric vehicle and an electric vehicle comprising the same are provided. The driving system comprises: a driving motor (1), a transmission (40) and a hydraulic system (50). The transmission (40) may include an input shaft (2), an output shaft (9), a first transmission unit (B1), a first clutch (6), a second transmission unit (B2) and a second clutch (3).