Motor Angle Sensor Correction During PWM Torque Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electric vehicles face vibration issues due to sudden changes in drive torque when switching between one-pulse and pulse-width modulation control methods without prior correction of the rotation angle sensor attachment error, which cannot be addressed during travel.
Innovation Solution
A control apparatus that acquires correction data to determine if the rotation angle sensor correction process has been performed, and if not, it switches to pulse-width modulation control to reduce vehicle body vibrations by performing the correction process while the vehicle is in motion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the correction process is not performed before shipping, then the vehicle can be shipped without additional correction procedures, but the drive torque suddenly changes when control method is switched causing vehicle body vibration and degraded riding comfort
Solution Approach 1:
The system performs the correction process in advance during a correction execution period before normal operation begins. This preliminary action ensures the rotation angle sensor error is corrected before the vehicle is shipped or before control method switching occurs, preventing drive torque sudden changes and vehicle body vibration while allowing the vehicle to be shipped without additional correction procedures.
2Reliability
If the correction process is performed while the vehicle is traveling under pulse-width modulation control, then the rotation angle sensor error can be corrected, but the control system becomes more complex
Solution Approach 1:
The system dynamically determines whether to execute the correction process based on the current control method being used. The correction execution determination unit checks if pulse-width modulation control is active, and only allows correction during this mode. This dynamic adaptation enables the system to perform correction while traveling without requiring permanent structural changes or additional hardware, thus limiting the increase in control system complexity.
3Device complexity
If the one-pulse control method is used, then the control is simpler, but the drive torque suddenly changes when switching control methods causing vehicle body vibration
Solution Approach 1:
The system uses feedback from the correction process to adjust the rotation angle sensor readings. By continuously monitoring and correcting the sensor error during pulse-width modulation control periods, the system ensures accurate rotation angle information is available when switching to one-pulse control, preventing sudden drive torque changes and vehicle body vibration while maintaining control method simplicity.
Data Source
AI summary
A control apparatus includes: a data acquisition part that acquires correction data indicating a content regarding a correction process which corrects an error of an angle at which a rotation angle sensor that measures a rotation angle of a rotor included in an electric motor is attached; a determination part that determines, based on the correction data, whether or not the correction process has been performed; and a control method determination part that determines, in a case where it is determined that the correction process has not been performed, that an inverter which supplies an AC current to the electric motor is controlled under a pulse-width modulation control.