Abstract: Control algorithm is the core of AC servo system. In order to improve the performance of system, on the basis of vector control system and Space Vector Pulse Width Modulation（SVPWM）, inverse matrix and projection of Uout on plane rectangular coordinate system are used to determine the nonzero vector movement time t1、t2. Then, a calculation method of vector switch point Tcm1、Tcm2、Tcm3 is given. A judgment method of sector which vector locate is given based on the one-to-one relationship between index number and sector. Simulation is carried on and some simulation results show that the system has good dynamic response and steady-state accuracy.

Key words: space vector pulse width modulation, key technology, nonzero vector, vector movement time, sector

摘要： 控制算法是交流伺服系统的核心。为了改善系统的系能，依据矢量控制理论及空间电压矢量脉宽调制原理，由已知逆矩阵和Uout在平面直角坐标系的投影，详细论述了非零矢量运动时间t1、t2的确定方法；给出了矢量切换点Tcm1、Tcm2、Tcm3的计算方法;根据索引号和扇区一一对应的关系，给出了矢量所处扇区的判断方法。进行了系统仿真，仿真结果表明整个系统具有较好的动态响应和稳态精度。

关键词: 空间电压矢量脉宽调制, 关键技术, 非零矢量, 矢量切换点, 扇区