针对三相感应电动机可以替代单相电动机接于单相电网运行,提出将三相感应电动机的一相绕组与电容器串联后再与另外一相绕组并联,然后与第三相绕组串联,构成Y接法三绕组单相感应电动机。基于等效电流法,对三绕组单相感应电动机的运行性能进行研究,建立三绕组对称运行的条件,分析匹配电容对电机性能的影响。结果表明由于电容器的影响,无法实现严格对称运行,提出依据额定负载下电磁转矩最大为目标函数的电容器优化方法。采用该联结方式在一台2.2 kW电机上进行了实验,结果表明选择适当的电容将提高电机的效率,与三相对称电机在三相对称电源上的运行相比较,该接法的电机具有较高的功率因数,且效率接近三相对称运行时的效率。
Three-phase induction motors could be operated by single phase supply replacing single-phase motors. The Y-connection three-winding single-phase induction motor is provided, in which one winding has a series connection with a capacitor connects to another winding in parallel and the two windings conneet to the third winding in series. Based on the equivalent current method, the operation performance of the motor is studied and the symmetrical operation condition is set up. The influence of capacitor on the performance is analyzed and the optimization method based on the most output torque with rated load is put forward. Experimental researches are carried out on a 2, 2 kW induction motor, and it is proved that the efficiency of the Y-connection three-winding single-phase induction motor could be improved by suitable capacitor and the motor has higher power factor and almost the same efficiency in comparison with the three-phase induction motor with three-phase supply.