Three-phase asynchronous motors with single-layer windings

Single-layer winding is embedded in each stator slot with only one coil effective edge of the winding, and thus its total number of coils is only half of the total number of slots in the motor. The advantages of single-layer winding are that the number of winding coils is less and the process is more straightforward; there is no interlayer absolute edge, so the utilization rate of the slot is improved; the single-layer structure will not occur between phase breakdown faults, and so on. The disadvantage is that the electromagnetic waveform generated by the winding is not ideal, the motor's iron loss and noise are more significant, and starting performance is also slightly worse, so the single-layer winding is generally only used for small-capacity asynchronous motors. Single-layer winding by the shape of its coil and end connection part of the arrangement of different can be divided into chain winding, cross-chain winding, concentric winding, ng cross concentric winding, and other forms of winding.
1. Chain winding
Three-phase asynchronous motor
Three-phase asynchronous motor [8]  
Chain winding is composed of single-layer coil elements with the same shape and width, which is named because each coil at the end of the winding is like a chain ring. Single-layer chain winding should pay special attention to the coil pitch should be an odd number, otherwise the winding will not be arranged.
2. cross-chain winding
Cross-chain winding when each pole and each phase of the number of slots 9 for more than 2 numbers of chain winding cannot be able arranged the arrangement, it is necessary to use a single, double-coil cross winding.
3. Concentric winding
Concentric winding in the same pole phase group of all the coils around the same center.
4. Crossed concentric winding
When the number of slots in each phase of each stage Q is more than 2, even numbers can be taken in the form of concentric winding.
Single concentric winding and cross concentric winding have disadvantages for the winding of winding. The embedded line is relatively simple, and he disadvantage is that the coil end is too long, too much wire consumption. Now, in addition to the occasional use in small-capacity 2-pole and 4-pole motors, nowadays hisbeen rarely used in this form of winding.