Hybrid Motor Resolver Offset Correction for Velocity Spike Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hybrid electric vehicle motors experience abnormal takeoff due to resolver offset errors, leading to potential motor burnout when the engine clutch is engaged and disengaged, as the motor torque is generated in the positive direction during zero torque control, causing increased motor velocity.
Innovation Solution
A method is implemented to prevent motor takeoff by checking the engine clutch disengagement, verifying zero motor torque command, and correcting the resolver offset by adapting a new offset value based on detected motor velocity and Vd* values, using a control structure to compensate for resolver offset fluctuations and maintain zero motor torque during clutch disengagement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If resolver offset correction is performed to compensate for manufacturing errors, then motor positioning accuracy is improved, but measurement precision deteriorates due to noise and correction errors causing abnormal motor velocity takeoff
Solution Approach 1:
The patent implements a feedback mechanism that continuously monitors motor velocity during zero torque control. When abnormal velocity increase is detected, the system feeds back this information to trigger resolver offset recalculation, creating a closed-loop control system that automatically corrects measurement errors while preventing harmful effects
Solution Approach 2:
The patent performs preliminary checks before executing zero torque control to determine whether the motor is in a no-load state. By anticipating potential resolver offset errors before they cause damage, the system recalculates the offset in advance, preventing abnormal velocity takeoff before it occurs
2Loss of energy
If zero torque control is implemented during engine clutch disengagement, then energy loss is reduced, but motor reliability deteriorates due to resolver offset errors generating positive torque that causes velocity takeoff and motor burnout
Solution Approach 1:
The system continuously monitors motor velocity during zero torque control and provides feedback when abnormal velocity increase is detected. This feedback triggers automatic resolver offset recalculation, ensuring the motor remains reliable while maintaining energy efficiency during clutch disengagement
Solution Approach 2:
The patent applies preliminary anti-action by detecting the no-load state before harmful torque generation occurs. When abnormal velocity is detected, the system immediately recalculates the resolver offset to counteract the erroneous positive torque, preventing motor burnout before it can occur
3Manufacturing precision
If resolver offset correction is performed using existing methods, then production deviation is adjusted, but device complexity increases due to additional correction logic and noise filtering requirements
Solution Approach 1:
The patent implements self-service by enabling the control system to automatically detect abnormal velocity conditions and trigger resolver offset recalculation without external intervention. The system serves itself by monitoring its own state and performing necessary corrections, reducing the need for complex external correction mechanisms
Solution Approach 2:
Instead of continuously recalculating resolver offset, the patent applies partial action by performing recalculation only when abnormal velocity is detected. This selective approach maintains manufacturing precision while avoiding the complexity of continuous correction systems
Data Source
AI summary
A method for preventing takeoff of a motor velocity of a hybrid electric vehicle, may include checking whether an engine clutch is disengaged while an engine and a motor are simultaneously driven, checking whether a command of motor torque is zero when the engine clutch is disengaged, and checking whether the motor velocity is normal while the command of the motor torque is zero, wherein when the motor velocity abnormally increases as a result of checking whether the motor velocity is normal, the motor torque is corrected to be zero.