Lockup Clutch Control During Supercharger Lag
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing lockup clutch control apparatus fails to correctly control slippage of a lockup clutch in a supercharged engine system when supercharger lag occurs, due to measurement errors that cause deviations between actual and measured torque values.
Innovation Solution
A lockup clutch control apparatus that includes a controller to set clutch engagement force based on measured torque input and determine if the engine is in a supercharger lag region, with operations to correct the engagement force by reducing it during lag conditions and adjusting it later to match actual torque values.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If clutch engagement force is set based on measured torque value, then control simplicity is maintained, but control accuracy deteriorates due to measurement error in supercharger lag region
Solution Approach 1:
The control device performs preliminary detection to determine whether the engine is operating in a supercharger lag region before setting the clutch engagement force. By anticipating the measurement error condition and preparing a correction strategy in advance, the system maintains accuracy without permanently increasing complexity.
Solution Approach 2:
The system changes the clutch engagement force parameter based on the detected operating region. When supercharger lag is detected, the control device adjusts the engagement force to compensate for the torque measurement deviation, thereby maintaining control accuracy despite the measurement error.
2Measurement precision
If clutch engagement force is increased to compensate for torque deviation, then slip control accuracy improves, but energy loss increases due to excessive engagement force
Solution Approach 1:
The control device applies different engagement force strategies to different operating regions. In the supercharger lag region, compensation is applied; in normal operating regions, standard control is used. This localized approach ensures accuracy only where needed, minimizing unnecessary energy loss in other conditions.
Solution Approach 2:
The system applies partial compensation rather than full compensation for torque deviation. By adjusting the engagement force to partially offset the measurement error rather than fully compensating, the system achieves adequate control accuracy while avoiding excessive energy loss that would result from over-compensation.
3Measurement precision
If clutch engagement force is decreased to match actual torque, then control accuracy improves, but slippage control deteriorates due to insufficient engagement force
Solution Approach 1:
The control device dynamically adjusts the clutch engagement force based on real-time detection of the operating region and slip conditions. Rather than using a fixed engagement force, the system continuously modifies the force to balance accuracy requirements with slippage control needs, optimizing both performance metrics simultaneously.
Solution Approach 2:
The system uses feedback from slip detection to adjust the clutch engagement force. By monitoring actual slip conditions and comparing them with target values, the control device refines the engagement force setting to achieve both accurate torque control and proper slippage management.
Data Source
AI summary
A lockup clutch control apparatus controls slippage of a lockup clutch to a desired slippage by manipulating clutch engagement force of the lockup clutch, wherein an engine is provided with a supercharger, and a torque converter is disposed between the engine and an automatic transmission, and provided with the lockup clutch. The lockup clutch control apparatus includes a controller configured to: set the clutch engagement force based on a measured value of torque inputted to the lockup clutch; determine whether the engine is operating in a predetermined supercharger lag region in which the measured value deviates from an actual value of the torque; and perform a first operation of correcting the clutch engagement force by reducing the clutch engagement force in response to determination that the engine is operating in the supercharger lag region.