Hybrid Powertrain Control for Shifting Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing powertrain systems face challenges in efficiently managing transmission operating range states and engine states to optimize fuel economy, torque output, and battery state-of-charge, particularly in response to varying operator torque requests and environmental conditions, leading to frequent and undesirable shifting events.
Innovation Solution
A method that determines the current and potential transmission operating range states and engine states, assigns biasing costs to operator torque requests, and selectively changes these states based on preferability factors to stabilize the operating range and minimize shifting, using a microprocessor to weigh the direction of changes in transmission input speed and filter noise in input speed values.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the transmission operating range state and engine state are frequently changed to optimize torque output and fuel economy, then the system adaptability improves, but the shifting stability deteriorates
Solution Approach 1:
The control system performs preliminary evaluation of multiple potential transmission operating range states and engine states by calculating preferability factors before actually switching states. This allows the system to anticipate optimal states and execute smooth transitions, improving both adaptability and shifting stability.
Solution Approach 2:
The system dynamically adjusts transmission operating range states and engine states based on real-time operating conditions, operator torque requests, and calculated preferability factors. This dynamic adaptation enables the system to optimize performance while maintaining stability through controlled transition timing.
2Measurement precision
If biasing costs are assigned to all potential transmission operating range states, then the torque request accuracy improves, but the computational complexity increases
Solution Approach 1:
The control system applies biasing costs selectively to specific transmission operating range states based on local operating conditions rather than uniformly to all states. This localized approach improves torque request accuracy for relevant states while reducing unnecessary computational overhead.
Solution Approach 2:
The system changes the biasing cost parameters dynamically based on current operating conditions, such as battery state-of-charge, vehicle speed, and operator torque requests. This allows accurate torque request evaluation while adapting computational requirements to actual system needs.
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
A method for controlling a powertrain system includes determining a current transmission operating range state and engine state, determining at least one potential transmission operating range state and engine state, providing at least one operator torque request, determining preferability factors associated with the current transmission operating range state and engine state, and potential transmission operating range states and engine states, wherein determining preferability factors associated with potential transmission operating range states includes assigning biasing costs to operator torque requests which reside within a pre-determined range of possible operator torque requests for at least two of the potential transmission operating range states, preferentially weighting the preferability factors for the current transmission operating range state and engine state, and selectively commanding changing the transmission operating range state and engine state based upon the preferability factors and the operator torque request.