Permanent magnet motor stator and multi-parallel-soft-winding transposition coil inserting method

Abstract

The invention provides a permanent magnet motor stator and a multi-parallel-soft-winding transposition coil inserting method of the permanent magnet motor. The method comprises the steps of winding stator coils which are in parallel winding with multiple leads in multiple groups, and reducing the winding difficulty of the coil. When the coil is inserted, all the coils are inserted into a groove layer-to-layer, and layers are formed in the groove; to prevent insulation among the coil turn from being damaged, a layer of thin film insulation material is padded on each group of coil, and insulating performance of the insulation is strengthened. Multiple coils which are in series connection with each branch circuit of a stator winding are located in different layers in the groove, that is, the branch circuit of which the multiple coils is located in different magnetism positions in the groove is formed, the influence of an skin effect caused by an alternating magnetic field can be lowered to the greatest extent, imbalance of currents among strands is lowered, motor vibration is reduced, and motor temperature raising is lowered.

Description

technical field [0001] The invention relates to the technical field of motors, in particular to a stator of a permanent magnet motor and a method for transposing and embedding wires of a plurality of parallel winding flexible windings. Background technique [0002] For permanent magnet motors with multiple parallel windings and soft windings, the stator coils often use circular coils with low cost and simple fabrication. In terms of motor design, soft windings are generally suitable for motors with low voltage levels. The number of turns of the stator coil is small, and the number of coils per turn is large. Parallel winding of multiple windings will bring the following problems: On the one hand, in the production of coils, multiple windings per turn require a large inventory of copper wires in the motor manufacturer, and at the same time, there are different tensions between the wires, which is difficult for winding. bring difficulty. Moreover, the lengths of different tu...

AI Technical Summary

Problems solved by technology

Parallel winding of multiple windings will bring the following problems: On the one hand, in the production of coils, multiple windings per turn require a large inventory of copper wires in the motor manufacturer, and at the same time, there are different tensions between the wires, which is difficult for winding. bring difficulty

Moreover, the lengths of different turns of the same coil are not equal, resulting in inconsistent resistance and reactance of each turn. After being embedded in the motor slot, the magnetic geometric positions of each strand at each point of the slot are different, resulting in the inconsistency of each strand of the permanent magnet motor. The back electromotive force between the strands is different, resulting in unequal current of each strand, and there is a large circulating current between the strands, which in turn causes an increase in the temperature difference between the strands, and the motor operates poorly

On the other hand, due to the effect of the alternating magnetic field in the motor, the magnetic field in different positions in the stator slot is different. Due to the skin effect, the current distribution between the strands of the winding will be uneven, resulting in uneven heating of the motor winding.

In addition, due to the influence of shape and position tolerances in the motor manufacturing process, there are large differences in the magnetic field in different slots, which intensifies the current imbalance between the strands of the winding, resulting in increased temperature rise and vibration noise of the motor winding.

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