鉴于大功率永磁同步电机传动系统低开关频率的限制及复杂工况对无机械式传感器控制的要求，本项目提出从SHMPWM技术入手进行大功率PMSM无机械式传感器控制的新思路。在保证对系统谐波抑制的同时，从削弱的谐波成分中提取幅值恒定、相角互差120° 的三相特定谐波成分信号，用于转子位置和速度估算。通过加强传统SHMPWM非线性超越方程组的约束条件，在保证降低系统谐波分量的同时使某一3k+1次谐波的幅值恒定，并且3k+1次保证三相信号相角互差120°，产生了所需的特定谐波成分信号；分析该新型调制技术的数值求解方法并对转子位置和速度观测器进行理论设计；构建系统的仿真和实验平台，进行系统实用技术研究。本项目的研究为实现大功率PMSM传动系统的谐波抑制和无机械式传感器控制提供分析和设计的科学依据，促进大功率PSMM传动系统技术的进步，同时为其它类型电机传动系统的谐波抑制和无机械式传感器研究提供新途径。

In view of the low switching frequency restriction of high-power permanent magnet synchronous motor (PMSM) drive system and longing for sensorless control in hostile conditions, a novel control scheme, born out of selective harmonic mitigation pulse width modulation (SHMPWM) technique, is proposed for the high-power PMSM sensorless control. Three-phase selective harmonic signals with constant amplitudeand phase angle difference between each 120° will be extracted for the mitigated harmonic components. The rotor position and speed can be estimated by the three-phase selective harmonic signals. The new enhanced constrains is placed on nonlinear transcendental equation of the traditional SHMPWM technique. The advantage of this scheme is that it can selectively generate constant amount of (3k+1)th order harmonic signal while guarantee that the undesired harmonic signals can be suppressed, and phase angle difference of three-phase selective harmonic signals can be guaranteed 120°, thus it provides enough injected sensing signal for the controller. The numerical method of the new modulation technique will be analyzed，the rotor position and speed observer will be designed, meanwhile the corresponding system simulation and experimental platforms will be built for the research on the practical performance of the system. Our research will provide the scientific basis of the analysis and design for the harmonic suppression and sensorless control of the high-power PMSM and other motors drive systems, which contributes to the advancement in the high-power electric drive system.