Research On Vector Control Strategy Of Seven-Phase Induction Motor For Electric Vehicle Based On DSpace

Vigorously developing new energy vehicles has become the only way for the country to realize a powerful automobile country.New energy vehicles are not only energy-saving and environmentally friendly,but also have the advantages of small noise,easy operation,etc.,which make them rapidly rise in the automotive industry.With the advancement of technology,people's demands for automobiles are also getting higher and higher,especially the requirements for motor systems are becoming more and more demanding.Compared with three-phase motors,multi-phase motors can not only achieve low-voltage high-power,but also have advantages such as high reliability,high torque density,and multiple degrees of freedom.This article takes a seven-phase motor as the research object,and realizes its optimal control and analysis by improving the control method.The main content of the article is as follows:First of all,in order to lay the foundation for the study,the mathematical model of the seven-phase motor in the d-q stationary coordinate system was established by the multi-phase motor magnetomotive force analysis and decoupling transformation,and the multi-phase motor has multiple degrees of freedom available.Advantage.A semi-physical simulation platform based on dSpace was built,and the control flow and functions of the platform were introduced.Secondly,in order to realize the seven-phase motor can realize greater torque and higher core utilization efficiency under the same voltage level,this paper introduces the principle of non-sinusoidal power supply and its achievable optimization.However,due to the fact that the traditional non-sinusoidal power supply is optimal under no-load conditions,the effect is significantly reduced as the load increases.This article analyzes the causes of the traditional non-sinusoidal power supply deficiency and improves it.Through the optimized non-sinusoidal control algorithm,the seven-phase motor is simulated.The simulation results show that the improved non-sinusoidal power supply can effectively improve the waveform of the air-gap flux linkage and basically eliminate the air-gap flux distortion.Through experiments,it can also be proved that this scheme can make the back electromotive force of the seven-phase motor form a nearly flat top wave.Finally,in order to improve the control performance of the motor,the modeling and simulation analysis of the seven-phase motor based on the fundamental wave plane from the open loop flux observer to the combined flux observer is performed.It is verified that the error accumulation of the open-loop flux linkage and the DC bias make the observation effect of the flux linkage poor,while the combined model avoids the formation of errors on the one hand,and on the other hand can combine the voltage model and the point of the current model,accurately Observe the motor flux linkage.Through accurate observation of the flux linkage,this paper also uses the flux observation model as a reference model to construct a model reference adaptive speed identification algorithm.Through simulation and comparison,it is found that the model reference adaptive system based on the combined model has the best speed identification effect.