基于扩展磁链观测的永磁同步电机转矩闭环矢量控制

用于风力发电和电动汽车等特殊应用场合中的永磁同步电机(PMSM)驱动器通常需要直接跟踪主控系统下发的转矩指令,而实际系统中通常不安装扭矩仪等转矩检测部件,因此,电磁转矩的准确获取对高精度转矩闭环至关重要。文中提出了一种基于最小阶扩展磁链观测器的实时定子磁链观测方案,并在此基础上完成电磁转矩的观测计算。该定子磁链观测方案不仅可以避免传统方案造成的积分饱和、相位或幅值偏差等不利影响,而且该观测方案具有较强的参数鲁棒性,其转矩观测计算精度基本不受PMSM交、直轴电感以及转子磁链的影响。11kW的PMSM仿真与实验验证了该方案的可行性和有效性。

Torque Closed-loop Vector Control Based on Extended Flux Linkage Observer of Permanent Magnet Synchronous Motor

The permanent magnet synchronous motor (PMSM) used in wind turbine and electric vehicle situations usually has to directly track the torque command issued by the main control system. As a matter of fact, however, no torque test components such as a torque sensor is available in an actual system. So the exact acquisition of the observed torque is of utmost importance for the torque control system. To enhance the torque observer performance, this paper proposes a real-time stator flux linkage observation method based on a minimum extended flux linkage observer, through which the stator flux linkage and the electrical torque are calculated. The proposed stator flux linkage observer is not only free from the flaws of the traditional pure integral strategy, such as saturation, phase shift, amplitude deviation, and so on, but also, as a pure integral strategy, is robust for parameter deviation, namely, the precision of the observed torque is basically unaffected by the direct- and quadrature- axis inductance and the rotor flux linkage. Simulations and experiments on an 11 kW PMSM have validated the performance of the proposed method.