Drive Unit Hold Control for Free-Wheel Towing on Slopes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electric vehicle towing methods lack efficient control mechanisms to stabilize the vehicle during towing, particularly on slopes, which can lead to unsafe rolling or movement.
Innovation Solution
A drive unit controller with a processor that receives free-wheel tow mode activation information, activates a hold mode, generates a zero-speed command, and sends it to a stabilizing system, using electric motor speed control to counter gravitational forces and prevent movement during towing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the electric vehicle is placed in neutral during towing, then the vehicle can be towed freely, but the vehicle may roll away or move uncontrollably on slopes
Solution Approach 1:
The patent replaces the traditional mechanical neutral gear positioning with an electric motor control system. The motor controller receives a free-wheel tow mode signal and automatically adjusts motor torque to counteract gravitational forces on slopes, eliminating the need for manual neutral positioning and choke placement while preventing uncontrolled movement.
Solution Approach 2:
The motor control system automatically detects slope conditions and adjusts motor torque without external intervention. When free-wheel tow mode is activated, the system self-regulates to maintain vehicle stability on slopes, eliminating the need for operators to manually position the vehicle or apply external braking forces.
2Device complexity
If traditional towing methods are used without motor control, then the towing process is simple, but the vehicle cannot be stabilized on slopes
Solution Approach 1:
The motor control system serves multiple functions: it enables free-wheel tow mode activation, detects slope grade conditions, calculates appropriate torque compensation, and maintains vehicle stability. This multi-functional approach integrates what would traditionally require separate systems into a single unified control mechanism.
Solution Approach 2:
The system receives slope grade information as feedback and dynamically adjusts motor torque accordingly. The controller continuously monitors vehicle conditions and modifies torque output to counteract gravitational forces on slopes, creating a closed-loop control system that maintains stability throughout the towing operation.
3Reliability
If motor control is activated during towing, then vehicle stability is improved, but the control system complexity increases
Solution Approach 1:
The patent combines the motor control functions with the existing drive unit controller, integrating slope detection, torque calculation, and stabilization control into a single control unit. This merging approach avoids adding separate dedicated stabilization systems and leverages the existing control infrastructure.
Solution Approach 2:
The system activates hold mode and applies torque compensation before the vehicle begins to move or roll on a slope. By anticipating and counteracting gravitational forces in advance, the system prevents uncontrolled movement rather than reacting to it, improving stability while maintaining straightforward control logic.
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 solution effectively stabilizes the electric vehicle during towing by maintaining zero speed and preventing rolling, ensuring safe operation even on slopes, by dynamically adjusting motor torque in response to slope grade information and external towing forces.
Implementation Method 1
A drive unit includes an electric motor, an encoder configured to generate motor speed information of the electric motor, an inverter configured to control operation of the electric motor
Data Source
AI summary
Various disclosed embodiments include illustrative drive unit controllers, drive units, and vehicles. In an illustrative embodiment, a drive unit controller includes a processor having computer-readable media configured to store computer-executable instructions configured to cause the processor to receive free-wheel tow mode activation information, activate a hold mode based on the received free-wheel tow mode activation information, generate a zero-speed command in response to the hold mode being activated, and send the generated zero-speed command to a stabilizing system of the associated vehicle.