永磁同步电机永磁磁链特定相位封锁PWM测量法

Permanent Magnet Flux Linkage Measurement Method for PMSM With PWM Blocked at a Specific Phase Point

针对已有方法的不足,提出了一种特定相位封锁PWM的永磁同步电机永磁磁链测量新方法。通过模型分析导出开路电压、电角频率与永磁磁链三者间的计算模型,得出非归一化和等功率变换归一化下的相关结论。使被测电机先加速到额定转速,在特定相位点封锁逆变器PWM信号使被测电机惯性制动,从而测得开路电压幅值并间接计算得永磁磁链。提出的新方法无需额外的拖动电机及机械联轴,且不存在逆变器死区时间非线性问题。所提方法通过了实验验证。

Aiming at deficiency in previous methods,a novel method was proposed to measure the permanent magnet flux linkage about PMSM with PWM blocked at specific phase point.It was derived a computation model about open-circuit voltage,electrical angular frequency and permanent magnet flux linkage.Besides,it comes to relevant conclusions under situations of non-normalization and normalization with coordinate transformation of constant power.The motor to be tested was accelerated to the rated speed,and then it's forced to be in inertia braking by blocking inverter’s PWM signals at a specific phased point.Then the open-circuit voltage amplitude was measured and the permanent magnet flux linkage was obtained by calculation indirectly.With the new method proposed,it has no need of extra driving motor,it has no mechanical axis coupling problem,and there is no problem of dead-time nonlinearity about the inverter.The present method was verified by experiments.