异步电动机起动电容容量的选择

New Methods of Selecting Capacitor Capacity for Capacitor Starting of Asynchronous Motor

异步电动机采用电容起动可在不降低起动转矩的同时有效降低起动电流对电网的冲击,但起动电容量的选择是关键。容量不足,则起动电流降低不明显;容量选择过大则不仅增加投入,而且可能在起动末期使电机端部电压异常升高,造成诸多不良影响。本文在分析目前选择方法的不足后,提出两种新的选择方法,并通过MATLAB软件对多台样机进行计算,验证两种选择方法的可行性和效用。

Asynchronous motor’s capacitor starting can effectively reduce the starting current impact on the power network without reduced starting torque, but the selection of starting capacity is the key. If capacitor capacity is short, the starting current reduction is not obvious. If it is too large, it not only increases the investment, but leads to abnormally high voltage at the motor side and causes a lot of adverse effects. After analyzing the shortcomings of current selection methods, this paper presented two new selection methods, and calculated some sample motors with the MATLAB software to prove the feasibility and usefulness of these methods.