Wheel Slip Control Using Predictive Torque Narrowing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional idling-sliding control systems for electric vehicles take a significant amount of time to initiate and complete the re-adhesion process, as they react only after the occurrence of idling-sliding, leading to prolonged adhesive force decrease periods.
Innovation Solution
An electric vehicle control device with an idling-sliding control unit that includes a detection unit and a torque command value generation unit, which anticipates potential idling or sliding events by using prediction signals to proactively narrow the torque command value, thereby reducing the time required for re-adhesion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional idling-sliding control is performed after detection of occurrence of idling-sliding, then re-adhesion characteristic is improved, but time from beginning of control until halt is prolonged
Solution Approach 1:
The control device performs preliminary narrowing of the torque command value when a prediction signal indicating anticipated idling or sliding is received, before actual idling-sliding occurs. This proactive measure prepares the system in advance, allowing faster response when idling-sliding actually happens, thus reducing the control time while maintaining effective re-adhesion characteristic.
Solution Approach 2:
The system applies counter-measures in advance by narrowing the torque command value range before idling-sliding occurs. The prediction signal triggers preliminary anti-action that prevents the full development of idling-sliding conditions, thereby reducing the severity and duration of control needed when actual idling-sliding occurs.
2Reliability
If torque command value is narrowed in range, then wheel re-adhesion is achieved, but torque variation occurs during operation
Solution Approach 1:
The control device dynamically adjusts the torque command value within a narrowed range based on real-time detection of idling-sliding conditions and prediction signals. This dynamic adjustment allows the system to maintain wheel re-adhesion while minimizing unnecessary torque variations by adapting the torque level to current operating conditions rather than applying fixed narrowing.
Solution Approach 2:
The system changes the torque command value parameter within a constrained range to achieve re-adhesion. By carefully controlling the parameter change magnitude and rate, the system achieves wheel re-adhesion while minimizing harmful torque variations that could affect ride quality or mechanical components.
Data Source
AI summary
An electric vehicle control device includes an idling-sliding control unit that provides control to reduce or prevent idling and sliding that may occur on a wheel of an electric vehicle. The idling-sliding control unit includes an idling-sliding detection unit for detecting idling or sliding that has occurred on the electric vehicle, and a torque command value generation unit that generates a torque command value used for reducing or preventing idling or sliding, based on output of the idling-sliding detection unit. When a prediction signal representing an anticipated occurrence of idling or sliding is inputted, the torque command value generation unit performs narrowing of the torque command value regardless of whether or not the idling-sliding control unit is performing idling-sliding control.