感应电动机混合坐标变换数学模型及应用研究
2018-12-21梁艳萍万银龙王晨光
梁艳萍 万银龙 王晨光
摘要:针对感应电动机的电磁转矩表达式中转子电流与气隙磁通的强耦合问题,采用αβ0变换和MT0变换的混合坐标变换法,使得感应电动机的电磁转矩表达式解耦。推导了混合坐标变换,并给出了感应电动机混合坐标变换数学模型。在混合坐标系和ABC坐标系下分别建立了感应电动机的仿真模型,通过对比仿真结果,验证了感应电动机混合坐标变换数学模型的正确性。在混合坐标变换的应用中,以磁链开环、转速闭环的间接矢量控制仿真系统为例,仿真结果表明感应电动机的定子电流经过混合坐标变换解耦为产生磁场的定子电流分量和产生转矩的定子电流分量,验证了混合坐标变换的有效性。
关键词:
电磁转矩;混合坐标变换;解耦
DOI:10.15938/j.jhust.2018.05.009
中图分类号: TM351
文献标志码: A
文章编号: 1007-2683(2018)05-0046-08
Induction Motor Hybrid Coordinate Transformation Model and Its Application
LIANG Yanping,WAN Yinlong,WANG Chenguang
(School of Electrical and Electronic Engineering, Harbin University of Science and Technology, Harbin 150080, China)
Abstract:For the strong coupling problem between the rotor current and the air gap flux in the expression of the electromagnetic torque expression of the induction motor, the hybrid coordinate transformation is adopted by the αβ0 transformation and the MT0 transformation, and the electromagnetic torque expression of the induction motor is decoupled. The hybrid coordinate transformation is deduced, and the mathematical model of hybrid coordinate transformation of induction motor is given. The simulation model of the induction motor is respectively established under the hybrid coordinate system and the ABC coordinate system. The mathematical model of the hybrid coordinate transformation in the induction motor is verified by comparing the simulation results. In the application of the hybrid coordinate transformation, the indirect vector control simulation system based on flux linkage openloop and speed closed loop is taken as an example. The simulation results show that the stator current of the induction motor is decoupled into the stator current component generating the magnetic field and the stator current component generating torque by the hybrid coordinate transformation, so the validity of the hybrid coordinate transformation is verified.
Keywords:electromagnetic torque; hybrid coordinate transformation; decoupling
0引言
感應电动机的动态数学模型是一个高阶、非线性、强耦合的多变量系统,从而使感应电动机的调速变得十分困难[1]。近几十年,感应电动机的调速技术出现了一些新的方法,如矢量控制法[2-6]、直接转矩控制法[7-9]、自适应控制法[10-11]等,这些新的调速方法的关键就在于坐标变换,文[12]推导了任意转速旋转的三相/两相坐标变换公式。文[13]研究了常见的4种坐标变换。文[14]介绍了坐标变换在异步电机中的应用条件和原则。
针对交流电机存在的强耦合问题,文[15]采用了dq0变换,建立了电压电流转换模型,对转速、磁链双闭环系统进行了仿真。文[16]提出了一种基于自适应PI控制的状态切换方法,通过控制电机转矩电流分量,将电机从I/F流频法平稳的切换到假定旋转的dq坐标系中。……
