异步电机铁心损耗计算方法的分析与研究

The Analysis and Research on the Calculation Method of the Core Losses in an Induction Motor

采用变频启动、自启动、串电阻启动等方式启动的异步电机内的组成部件中的电磁场分布并不相同,因此各组成部件的损耗分析方法也应各不相同。各种形式的斯坦梅茨方程可分析计算铁心损耗,且斯坦梅茨方程中的系数可由硅钢片制造商提供的损耗曲线获得,然而,硅钢片制造商提供的损耗曲线仅能在几个固定的频率下获得。采用了一种曲线拟合技术,可计算任意频率下的损耗曲线。为验证该方法,搭建了实验平台,分析不同负载转矩下、不同开关频率下异步电机的损耗。对比结果表明,该方法能够准确地预测异步电机的铁心损耗。

The induction motor can be started by the grid,the PWM converter,the resistance in series and so on.By different starting mode,the electromagnetic field distribution(EFD)in the different part of an induction motor is different.Thus,the calculation method for the core loss in the different part of an induction motor is also different.Various types of Steinmetz equations can be applied to calculate the core loss,and the coefficients in Steinmetz equations are obtained from the core loss data,which is provided by the manufacturer.While the core loss data provided by the manufacturer is at some certain magnetization frequencies.A curve fitting method which could calculate the core loss data at any magnetization frequency was proposed.To verify this method,an experiment setup was built to analyze the core losses of induction motor with different load torque and different switching frequency was proposed.The comparison results show that this method can predict the core losses in an induction motor accurately.