Motor Control Device Torque Smoothing for Vibration Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional motor control devices experience abrupt torque variations during vibration-suppression, leading to deteriorated follow-up characteristic accuracy in current feedback control, resulting in power wastage and potential battery and inverter life issues.
Innovation Solution
A motor control device with a main torque control value calculation unit and a vibration-suppression torque control value calculation unit, including original control value calculation, guard processing, and smoothing units to restrict and smooth torque control values, preventing abrupt changes and maintaining vibration-suppression effects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If guard values are applied to vibration-suppression torque to protect the motor, then motor protection is improved, but abrupt torque variations occur that deteriorate current feedback control accuracy
Solution Approach 1:
The patent applies smoothing processing to the vibration-suppression torque control value before it is added to the main torque control value. This preliminary smoothing action prevents abrupt torque variations from occurring in the first place, thereby maintaining current feedback control accuracy while still providing motor protection through the guard values.
Solution Approach 2:
The patent introduces a smoothing unit as an intermediary component between the guard processing unit and the torque addition unit. This smoothing unit acts as a mediator that processes the vibration-suppression torque control value to eliminate abrupt variations, allowing both motor protection and control accuracy to be achieved simultaneously.
2Stability of the object's composition
If vibration-suppression torque control is applied to mitigate torque ripple, then torque fluctuation is reduced, but abrupt changes in torque control value cause power wastage and affect battery and inverter life
Solution Approach 1:
The smoothing unit performs preliminary processing on the vibration-suppression torque control value to eliminate abrupt changes before the torque is applied to the motor. This prevents the harmful effects of sudden torque variations, including power wastage and stress on battery and inverter components, while maintaining the vibration-suppression benefit.
Solution Approach 2:
The patent converts the potentially harmful abrupt torque variations into beneficial smooth torque transitions through smoothing processing. The guard values that would normally cause abrupt changes are processed to create gradual transitions, transforming a harmful effect into a beneficial one that maintains both torque stability and system reliability.
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
A controller (40) performs processing for calculating a main torque control value, processing for outputting a final control torque value based on the main torque control value and a vibration-suppression torque control value for mitigating torque fluctuation that occurs when a rotating electric machine is operated at the main torque control value, and processing for calculating the vibration-suppression torque control value. The processing for calculating the vibration-suppression torque control value includes processing for calculating an original control value serving as a source of the vibration-suppression torque control value, processing for performing guard processing for restricting the original control value by using a vibration suppression guard value, and processing for smoothing an angular portion where rate of change is discontinuous, that is generated in the torque control value that has been subjected to the guard processing.