Vehicle Motor Control Apparatus for Steering System Failure Demagnetization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In vehicle electric power steering systems, motor failures due to short circuits or disconnections can lead to the generation of braking torque, disrupting steering operations, as existing systems fail to effectively manage such failures by simply stopping the motor supply without preventing residual torque.
Innovation Solution
A vehicle motor control apparatus and method that includes a motor failure sensor to detect failures and a motor controller to apply a demagnetization current, permanently demagnetizing the motor's magnet to prevent braking torque, even in cases where the failure type is not specifically identified.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the motor supply is stopped when a failure occurs, then the motor operation is interrupted, but braking torque is generated as the rotor rotates, disturbing the driver's steering
Solution Approach 1:
The patent applies a demagnetization current to the motor windings after failure detection, which generates a magnetic field that opposes and cancels the residual magnetism in the rotor magnets. This converts the harmful braking torque effect into a beneficial demagnetization process, eliminating the rotor's magnetic field and preventing further braking torque generation during rotor rotation
Solution Approach 2:
The patent changes the electrical parameter of the motor by applying a specific demagnetization current pulse with sufficient amplitude and duration to permanently alter the magnetic state of the rotor magnets. This parameter change (applying external current) transforms the motor from a state with residual magnetism to a demagnetized state, eliminating the harmful braking effect
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
Enables stable steering operations by preventing or minimizing braking torque generation during motor failures, ensuring safe and efficient vehicle control even when the motor is malfunctioning.
Implementation Method 1
a motor controller configured to apply a demagnetization current to the motor for permanently demagnetizing the magnet in the motor
Data Source
AI summary
The present disclosure relates to an apparatus and method for controlling a motor in which a failure has occurred in a vehicle steering system. A vehicle motor control apparatus according to an embodiment may include a motor failure sensor configured to determine whether a failure has occurred in a motor based on information of a current flowing in each phase of the motor provided in a vehicle steering system, and a motor controller configured to apply a demagnetization current to the motor for permanently demagnetizing the magnet in the motor when the failure has occurred in the motor. Accordingly, a driver is capable of performing stable steering even when the motor has failed.