Motor Output Torque Estimation Using a State Observer
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Solution Overview
Problem
Existing methods for obtaining the actual output torque of a motor in new energy vehicle drive systems are ineffective, complex, and inaccurate.
Innovation Solution
A torque obtaining method that involves obtaining the rotation speed, current, and flux linkage of the motor, determining the electromagnetic torque, and inputting these parameters into a preset status observer to accurately calculate the actual output torque.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If sensor sampling, power balancing, or flux linkage estimating methods are used to obtain actual output torque, then torque acquisition can be implemented, but the methods are either ineffective, complex, or inaccurate
Solution Approach 1:
The patent replaces traditional mechanical sensor-based torque measurement methods with an electrical parameter-based calculation system. By using current, flux linkage, and rotation speed data from existing sensors combined with mathematical models (electromagnetic torque formula and state observer), the system achieves accurate torque acquisition without additional mechanical torque sensors, thereby improving accuracy while maintaining system simplicity
Solution Approach 2:
The patent introduces a state observer as an intermediary computational layer that processes electrical parameters (current, flux linkage, rotation speed) to derive torque information. This intermediary system acts as a mathematical mediator that transforms easily measurable electrical quantities into accurate torque estimates, resolving the contradiction between measurement accuracy and system complexity
2Measurement precision
If additional parameter collection modules are added to the drive system to obtain motor parameters, then measurement accuracy can be improved, but device complexity and cost increase
Solution Approach 1:
The patent makes the existing drive system components multi-functional. The current sensors, flux linkage calculations, and rotation speed measurements originally intended for motor control are simultaneously utilized for torque acquisition. This universal use of existing components eliminates the need for additional dedicated torque measurement hardware, maintaining measurement accuracy while avoiding increased system complexity
Solution Approach 2:
The system uses its own existing operational parameters (current, flux linkage, rotation speed) to self-determine torque information without external assistance. The drive system's built-in sensors and computational capabilities serve the dual purpose of motor control and torque measurement, eliminating dependency on additional parameter collection modules
Data Source
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AI summary
Embodiments of this application provide a torque obtaining method and device, a motor controller, and a readable storage medium. The torque obtaining method includes: obtaining a rotation speed of a motor; obtaining a current of the motor; obtaining a flux linkage of the motor; determining an electromagnetic torque of the motor based on the current and the flux linkage; and inputting the rotation speed and the electromagnetic torque into a preset status observer, and obtaining an observed value of an actual output torque of the motor, where the observed value is output by the status observer. The obtaining method is intended to obtain the actual output torque effectively, simply, and accurately.