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Abstract：In view of the low voltage level of electric vehicle power battery and low efficiency of driving system, the quasi-Z source inverter is used to improve dynamic performance of the interior permanent magnet synchronous motor driving system for electric vehicles, and hybrid efficiency optimization control is adopted for system steady state. The operating characteristics of quasi-Z source inverter are analyzed, a control strategy of DC bus voltage is proposed and quasi-Z source capacitance voltage expression is determined. Efficiency optimization control is used in steady state, motor loss expression is deduced, and the optimized ratio between excitation component and torque component of air gap current is calculated to get the direct axis current sub optimal value. Then with this value as initial value, an improved golden section algorithm which is fast and robust is used to find the best system operating point. The dynamic stator current distribution is also added to improve the dynamic response speed of the motor. Simulation and experimental results show that, the proposed control strategy can significantly improve the dynamic performance in high speed area and response speed of driving motor, also the steady-state efficiency of system is improved about 4%.Key words：electric vehicles；interior permanent magnet synchronous motor；quasi-z source inverter；dynamic performance； steady-state efficiency 0 前言 1

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Three-dimensional computer software have much to accomplish in the current application areas because they all have powerful modeling and simulation and recycling functions of real scenes. Today the most well-known and widely used 3D software should be 3DSMAX software, which is widely used in construction, decoration, video advertising and other areas. It offers us many modeling functions and various modeling methods. These features are easy to operate and can produce satisfactory products. 3DS MAX software has a similar modeling theory with the other modeling software, but its modeling menu commands are arranged very differently. As modeling steps and parameter adjustment and the features chose to make the model have influence on the efficiency and quality of modeling, designers should adjust their thoughts and adapt to the modeling methods and strategies of the software. Thus they can improve their ability and efficiency of modeling.

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