Research On Maximum Torque Per Ampere Control Of Permanent Magnet/reluctance Hybrid Rotor Double-stator Motor

In recent years,with the rapid development of industrial science and technology in various countries,the demand for metals and related ore materials involved in production and processing is increasing.There is still a gap between the mining technology of mineral resources in China and that of developed countries.In order to improve the safety and efficiency of mining operations,the optimization and upgrading of mining machinery is imperative.As the main part of mining machinery,the motor system of mine conveyor belt plays an important role.Based on the project of National Natural Science Foundation of China,this thesis aims at a new type of Permanent magnet/reluctance hybrid rotor double stator motor（PM/RHR-DSM）for mining,The Maximum torque per ampere（MTPA）control strategy is proposed to reduce system loss and improve system efficiency.The main research contents of this thesis include the following aspects:（1）The research status of double stator motor and its control method at home and abroad is described,and the structure and working principle of the new PM/RHR-DSM is deeply studied.According to the characteristics of PM/RHR-DSM two sets of stator windings in series,the mathematical model of the motor in three-phase stationary coordinate system,twophase stationary coordinate system and synchronous rotating coordinate system is derived.The constraint conditions of PM/RHR-DSM under vector control are analyzed theoretically.Various operating states of PM/RHR-DSM are analyzed by the voltage and current limit circle.（2）According to the electromagnetic torque equation of the mathematical model in the synchronous rotation coordinate system,the MTPA control algorithm expression suitable for PM/RHR-DSM is derived,and its MTPA curve is obtained.Then,a MTPA based double stator PM/RHR-DSM vector double closed-loop control system is built,and the simulation analysis of the control system is carried out by using software,and the results verify the effectiveness of the proposed MTPA algorithm.（3）The inner loop of control system adopts current loop controller with voltage feedforward compensation.Due to the MTPA module in the velocity outer loop,the nonlinear factor in the whole control system is increased,which makes the parameter setting of PI controller difficult.Therefore,according to the working conditions of the motor used in mining conveyor belt,the improved particle swarm optimization（PSO）algorithm is used to set the parameters of the external loop controller,and the stability of the motor speed waveform is improved through simulation.（4）Considering the influence of working environment on motor parameters,an online parameter identification algorithm of extended Kalman filter（EKF）suitable for PM/RHRDSM is proposed.In order to enhance the adaptability of traditional MTPA,the algorithm continuously updates the optimal combination of d-axis and q-axis currents through real-time monitoring of the motor’s cross-axis inductance.Finally,when the inductance parameters of the motor change,the MTPA control system based on EKF is simulated,and the results verify that the proposed algorithm has high identification accuracy and good practicability.