Motor Generator Controller Voltage Step-Up Resolver Learning
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Solution Overview
Problem
In electric vehicles and hybrid electric vehicles, the inaccurate detection of the angle of rotation due to a deviation in the point of origin of the resolver leads to inappropriate control of the motor generator, especially before the completion of learning-based correction, resulting in excessive or insufficient output torque.
Innovation Solution
A control unit sets a higher stepped-up voltage using a step-up converter when the learning of the point of origin of the angle-of-rotation sensor has yet to be completed, enabling maximum voltage step-up and disabling rectangular wave control to ensure stable motor operation through PWM control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If learning-based correction of resolver point of origin is not completed, then the motor generator can operate without accurate angle detection, but the output torque becomes excessively high or low leading to malfunction
Solution Approach 1:
The patent changes the voltage parameter supplied to the motor generator based on the learning completion status. When learning is not completed, a higher voltage is supplied to compensate for the inaccurate angle detection, ensuring the motor can still operate reliably despite the measurement precision issue.
Solution Approach 2:
The control system dynamically adjusts the voltage supplied to the motor generator based on the learning completion flag. The voltage is higher when learning is not completed and returns to normal levels when learning is completed, making the system adaptable to different operational states.
2Power
If rectangular wave control is used before learning completion, then the motor can operate in high torque mode, but the deviation in resolver point of origin causes significant control errors
Solution Approach 1:
The patent changes the control parameter (voltage) based on the learning status to compensate for the measurement precision issue. By supplying higher voltage when learning is not completed, the system maintains adequate power output despite the inaccurate angle detection that would otherwise cause significant control errors.
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
This approach prevents malfunctions during motor operation before the completion of learning and maintains stable torque control by broadening the operational range of PWM control, reducing the impact of resolver origin deviations.
Implementation Method 1
a step-up converter 12 for stepping up a direct current output from the battery 10
Implementation Method 2
The resolver detects, by means of a coil, a magnetic field that is generated in response to the rotation of the motor generator to detect the angle of rotation of the motor generator
Data Source
AI summary
An alternating current that is to be supplied to a motor generator is controlled by controlling an inverter using a target output of the motor generator and a result of detection of an angle-of-rotation sensor, and a voltage step-up is controlled in accordance with the target output of the motor generator. During operation of the motor generator, a stepped-up voltage obtained through the step-up converter is set to be higher (S13) when learning of the point of origin of the angle-of-rotation sensor has yet to be completed (S11), than when learning of the point of origin of the angle-of-rotation sensor has been completed. This eliminates malfunctions occurring in motor operation when learning of the point of origin of the angle-of-rotation sensor has yet to be completed.