A torque calibration method for an electric vehicle AC induction motor

Abstract

The invention discloses a torque calibration method for an AC induction motor of an electric vehicle. When the AC induction motor of the electric vehicle controls the electric vehicle, the torque calculation formula is used to calculate the expected torque Converted to desired torque current , and then realize torque control according to the rotor field-oriented vector control algorithm; before torque calibration, by comparing the error trend between the expected torque curve and the actual torque curve, adjust the motor rotor time constant and mutual inductance Two parameters, so that the actual torque is close to the expected torque, and the actual torque calibration is realized; on the basis of the traditional vector control algorithm, the present invention sequentially passes the motor rotor time constant on the basis of the original motor parameters and mutual inductance The calibration of the actual torque is completed; in the whole calibration process, the torque output of the control motor is stable and accurate, which can meet the torque control accuracy requirements of the electric vehicle drive system, and also avoids the cumbersome torque calibration method using the look-up table method .

Description

technical field [0001] The invention relates to electric vehicle motor control technology, in particular to a torque calibration method for an electric vehicle AC induction motor. Background technique [0002] With the continuous growth of global automobile production and ownership, traditional automobiles have brought about serious environmental pollution and the increasingly urgent global oil resource crisis. "Smoggy weather" and "high oil prices" have made the electric vehicle industry start Flourish. [0003] The power system of an electric vehicle is an electric drive system, and motor control technology is an electric drive system and one of the core technologies of an electric vehicle. At present, the motors used in the electric drive system of electric vehicles mainly include AC induction motors and permanent magnet synchronous motors. Among them, AC induction motors are widely used in electric vehicles due to their high reliability, simple structure, low cost, simp...

AI Technical Summary

Problems solved by technology

However, the AC induction motor is essentially a complex object with multivariable, nonlinear, time-varying parameters, and strong coupling. The electromagnetic parameters such as resistance, inductance, and mutual inductance of each phase winding of the motor are usually difficult to measure or estimate accurately, and are easy to change with temperature changes. , and due to the difference between the motor electromagnetic design parameters and the actual parameters, it is difficult to accurately estimate the rotor magnetic field position, which leads to the error between the torque calculated by the formula method and the actual torque, so how to complete the torque calibration of the AC induction motor and realize the output of the motor Accurate control of torque is the difficulty of electric vehicle motor control

Images