中文摘要：

传统直接转矩控制转矩、磁链和电流脉动较大，速度传感器的安装容易使系统可靠性降低、成本增加。为解决以上问题，采用扩展卡尔曼滤波器对定子磁链进行观测，并对转速进行估计，实现表面式永磁同步电机无速度传感器直接转矩控制，克服传统直接转矩控制中积分器的缺陷，保持直接转矩控制固有的转矩响应快和系统鲁棒性强的优点，能够对电机参数变化、负载扰动具有较强的鲁棒性，有效地改善了系统的动、静态运行性能，仿真和实验验证了该方法的可行性和有效性。

英文摘要：

There exist some problems of torque ripples and flux ripples and current ripples in traditional direct torque control （DTC）. System with speed sensor has lower reliability and higher system cost. To solve these problems, an Extended Kalman Filter （EKF） was established to observe stator flux linkage and estimate motor speed, thus speed sensorless direct torque control for surface permanent magnet synchronous motor （SPMSM） was realized. The deficiencies of integrator in traditional DTC were overcome. Rapid torque response and strong robustness of direct torque control method were still maintained. Meanwhile, the system based on EKF is robust to motor parameters variation and load disturbance. The dynamic and static system performances were dramatically improved. The simulation and experiment results have verified the feasibility and effectiveness of this method.