异步电动机功率因数特性研究

Study of Asynchronous Motor Power Factor Characteristic

异步电动机的转差率是一个非常重要的参数,分析异步电动机的工作原理、运行状态基本上离不开转差率,而且异步电动机的一些主要参数(如功率因数)和转差率密切相关。通过分析异步电动机的等效电路图,推导出了电机功率因数角的数学表达式,得出了在电机以及所接电源确定的情况下,其功率因数角仅取决于电机的转差率的结论。应用MATLAB曲线拟合功能,得出了转差率和功率因数的二维曲线。对转差率的分析发现,转子铜耗是转差率的内在实质,它的外在表现为电机转速较同步转速有所降低。

The slip ratio of the asynchronous motor is an important parameter, the asynchronous motor working principle and running state will not be analyzed without it. The important parameter such as power factor is closely related to the slip ratio. The mathematical expression of the motor power factor angle was calculated according to the asynchronous motor equivalent circuit diagram. When the motor and the power source were chosen, the motor power factor angle was depended only on the slip ratio. The two-dimensional curve of the slip ratio and power factor angle was generated by the application of the curve fitting in MATLAB. Through the analysis of the slip ratio, the conclusion was reached that the rotor copper loss was the essence of the slip ratio, and the motor speed＇s reduction was the external phenomenon.