| 摘要 |
PURPOSE:To reduce the number of changing-over contactors and motor lead wires for making small-sized and light by arranging two pieces of stator windings in two steps inside of the stator slots to change-over each winding according to the setting of speed ranges. CONSTITUTION:Inside of the slots of a stator the two respective stator windings C1u'-C1w' and C2u'-C2w' each phase are arranged in two steps and between said stator windings the contactors 1Mu-1Mv and 2Mu-2Mw changing-over the connection thereof are provided. And controlling said contactors, the respective phases stator windings are series-star connected in the low speed rotation range while each phase one stator winding is star or delta connected in the high speed rotation range. Thereby the number of three phase contactors and that of the motor lead wires required for changing-over can be reduced enabling to make small-sized and light as well as to obtain an electric characteristic equal to the former star and two delta changing-over system. |
