Research On Asynchronous Motor Model Considering Synthetically Time-varying Parameters

With the maturity of AC asynchronous motor control theory,motor control technology has evolved from scalar control based on motor steady state model to vector control based on motor dynamic model.Accurately grasping the motor parameters during the operation process and establishing the mathematical model of the motor as accurate as possible are the premise of achieving high-performance vector control of the asynchronous motor.This thesis focuses on the research of asynchronous motor model considering time-varying parameters,and the feasibility and effectiveness of the dynamic model of the motor are verified by simulations and experiments.A detailed theoretical analysis of the time-varying characteristics of the motor parameters is carried out and verified by motor experiments.According to the theoretical analysis and actual motor experiments,the ANSYS motor model is established.Based on motor experiments and simulation results of the ANSYS model,the time-varying characteristic curves of the motor parameters of the example motor are obtained.Aiming at the nonlinear dynamic model of asynchronous motor,starting from the ideal mathematical model,the dynamic models of the motor considering the iron loss and the main magnetic saturation are deduced respectively.Combined with the time-varying characteristic curves of the motor parameters obtained in the previous part,the nonlinear dynamic model considering iron loss,skin effect and magnetic saturation is completed.Based on this model,these nonlinear factors are simulated independently and the influences on the motor operation process are analyzed.In order to build the dynamic thermal model of the asynchronous motor,the heat conduction parameters and heat transfer parameters of the motor components are analyzed and calculated from the heat transfer in the motor.According to the motor loss distribution,a 5-node asynchronous motor dynamic thermal network model is built,and it is verified by ANSYS model simulations and motor experiments.The above-mentioned motor nonlinear model and dynamic thermal model are connected by the motor loss calculation model.Finally,the model of the asynchronous motor considering the time-varying parameters is completed.The feasibility of the motor model is verified by motor experiments.Figures:52,Tables:8,References:59...