Hybrid Powertrain Dual Clutch Transmission Gear Shift Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hybrid vehicles experience power interruptions during gear changes due to the disconnective nature of existing powertrain configurations, which can impact efficiency and smooth driving.
Innovation Solution
A powertrain configuration utilizing a Dual Clutch Transmission (DCT) with two separate power paths and an Electronic Control Unit (ECU) to manage clutch engagement and gear shifts, maintaining mechanical connection between the electric motor and the power path during gear changes, allowing for continuous propulsion or regenerative braking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional transmission with single clutch is used for gear changes, then the structure is simpler, but power interruptions occur during gear shifts
Solution Approach 1:
The transmission is segmented into two separate power paths (first and second power paths) with independent clutches (first and second clutches). This segmentation allows one power path to be engaged while the other is disengaged, enabling smooth gear transitions without power interruption. The first power path handles odd gears while the second power path handles even gears, ensuring continuous power delivery during shifts.
Solution Approach 2:
The dual clutch transmission maintains continuous useful action by ensuring that while one clutch is disengaging, the other clutch is already engaged or ready to engage. This overlapping engagement sequence prevents any interruption in power transmission from the input shaft to the output shaft, maintaining continuous propulsion during gear changes.
2Ease of operation
If dual clutch transmission with two power paths is used, then power interruptions are reduced, but the device complexity increases
Solution Approach 1:
The first and second power paths share common components including the input shaft, output shaft, and main gear box. This multi-functionality allows the same physical components to serve multiple purposes - the input shaft receives power from the engine regardless of which clutch is engaged, and the main gear box handles gear transitions for both power paths, reducing overall system complexity despite having dual clutches.
Solution Approach 2:
The patent merges the first and second power paths by having them share common transmission components (input shaft, output shaft, main gear box). This combining approach reduces the total number of separate components needed, as the two power paths are integrated rather than completely separate, thereby managing device complexity while maintaining smooth operation.
3Use of energy by moving object
If the electric motor is disconnected during gear changes, then the powertrain structure is simpler, but power interruptions and efficiency are reduced
Solution Approach 1:
The electric motor maintains continuous useful action by staying connected to the second power path throughout gear changes. During transitions between odd and even gears, the electric motor remains engaged and can provide supplemental torque or perform regenerative braking, ensuring continuous energy utilization and preventing power interruptions that would waste energy.
Solution Approach 2:
The electronic control unit continuously monitors the operating conditions and dynamically adjusts the engagement of the first and second clutches based on real-time feedback. This feedback mechanism optimizes the switching between power paths to maintain fuel efficiency while coordinating with the electric motor to ensure smooth transitions and maximize energy recovery during braking events.
Data Source
AI summary
A powertrain for a hybrid vehicle includes a first propulsion unit for powering the vehicle, a second propulsion unit for powering the vehicle, a Dual Clutch Transmission (DCT), and the second propulsion unit the ECU is programmed to control the gear shift such that when a gear shift of the first propulsion unit is made in order to change the overall gear ratio from the first input shaft to the output shaft by changing the double clutch engagement from the second clutch, engaging the second power path, to the first clutch, engaging the first power path, the power connection between the second propulsion unit and the second power path is maintained.