3 results about "Rotor time constant" patented technology

The application provides a method and device for adjusting the time constant of an asynchronous motor rotor, and a current correction method, device and system, and relates to the technical field of motor control. The method comprises the following steps: obtaining the rotor electric angular velocity, resistance and inductance; obtaining the three-phase current and three-phase voltage of the motor; using a current model to calculate a first torque according to the rotor d-axis flux, rotor q-axis flux, initial rotor time constant, stator d-axis current and stator q-axis current; using a voltage model to calculate a second torque according to the stator alpha-axis flux, stator beta-axis flux, stator alpha-axis voltage, stator beta-axis voltage, stator alpha-axis current and stator beta-axis current; making the deviation of the first torque relative to the second torque within a preset range to generate a rotor time constant compensation value; and compensating the initial rotor time constant. The application solves the problem of poor torque control accuracy of the asynchronous motor caused by the calculation of the rotor time constant based on the offline measured rotor inductance and resistance for controlling the stator d-axis current and stator q-axis current.

This application provides an adaptive field weakening control method and apparatus under sensorless conditions. The method includes: planning reference values ​​for excitation current and torque current of an induction motor in a high-speed field weakening region; modifying the voltage flux linkage model in the MRAS speed observer and compensating the rotor time constant in the current flux linkage model to improve the accuracy of speed observation; performing adaptive complex vector current decoupling on the reference values ​​for excitation current, torque current, actual excitation current, and actual torque current to obtain reference values ​​for excitation voltage and torque voltage of the induction motor; performing flux linkage tracking on the reference values ​​for excitation voltage and torque voltage to obtain corresponding pulse width modulation (PWM) waves; and using the PWM waves to drive an inverter to achieve adaptive field weakening control of the motor. This application enables adaptive field weakening control of the induction motor even when it is operating at high speed.

The application provides a kind of asynchronous motor vector control method based on Kalman filtering, comprising the following operations: determining the initial value of the accurate estimation value of target torque current, target flux current and rotor time constant of the vector control of asynchronous motor;The following steps are cyclically executed: real-time acquisition of the voltage, current and speed of asynchronous motor;The real-time value of the stator torque current, stator flux current, stator torque voltage and stator flux voltage of asynchronous motor is calculated;Determine the rotor time constant identification measurement value based on the adaptive rate of the rotor time constant of asynchronous motor;Determine the rough estimation value of rotor time constant and Kalman filtering gain at the current time;Determine the accurate estimation value of rotor time constant at the current time;The vector control of asynchronous motor is based on the accurate estimation value of rotor time constant at the current time, target torque current, target flux current.The method of the application can effectively reduce the fluctuation of rotor time constant identification result while ensuring the identification accuracy.