Research Of On-line Parameter Identification For Asynchronous Motor Based On Improved Least Squares

AC motor control system is a multivariable, nonlinear, strong coupling, parameters time-changing system. Vector control, adaptive control, direct torque control and the other high performance control method are built on the precise mathematical model of the motor. It is necessary to estimate the exact parameters of the motor before establish the precise mathematical model. This paper focuses on the study of induction motor on-line parameters identification. The main works are the following:1. By using coordinate transformation, the asynchronous motor mathematical model under the two-phase stationary and synchronous rotating coordinate system is established.2. The principle of induction motor vector control is introduced. The affecting of motor parameters on the induction motor vector control system is analyzed.3. An on-line parameters identification mathematical model of induction motor is built, and an asynchronous motor on-line parameters identification method is presented. Simulation model is constructed, and corresponding experiment simulations are carried on.The simulation results show that this identification method can identify the parameters of the motor effectively, such as stator resistance, inductance and rotor resistance, inductance. This will provide a theoretical foundation for the further study of precise control system.