摘  要：在永磁同步电动机控制系统中，当转速增加使逆变器输出电压达到最大值时，需要采用一定的弱磁调速策略来进一步增大电机转速。引入SVPWM过调制算法可以在逆变器直流侧电压不变的情况下增大其交流电压输出，从而扩大电机的弱磁调速范围。该文对目前应用较普遍的一种过调制算法进行讨论，并针对算法计算量大的问题进行改进，提出一种新的过调制算法。将两种算法分别应用于永磁同步电机的弱磁调速系统，对比分析系统的控制性能。
关键词：永磁同步电机；弱磁调速；过调制

Abstract: In permanent magnet synchronous motor control system, flux-weakening control algorithm is used for achieving higher speed when the output voltage of inverter reaches its maximum as increasing of speed. Since intruducing of SVPWM overmodulation algorithm is able to increase the output voltage of inverter with its DC side voltage unchanged, the flux-weakening operation area may be extended. This paper analysed the shortcoming of a general-uesd SVPWM overmodulation algorithm and proposes improvements. A new overmodulation algorithm was set up for overcomeing needed large computing amount in the former algorithm. The two kinds of algorithms were applied to the field-weakening control system respectively and the control performances were compared and analysed.
Key Words: Permanent magnet synchronous motor; flux-weakening; overmodulation